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Sample records for sublethal toxic effects

  1. Fumigant Toxicity and Sublethal Effects of Artemisia khorassanica and Artemisia sieberi on Sitotroga cerealella (Lepidoptera: Gelechiidae).

    Science.gov (United States)

    Naseri, B; Abedi, Z; Abdolmaleki, A; Jafary-Jahed, M; Borzoui, E; Mozaffar Mansouri, Seyed

    2017-09-01

    Fumigant toxicity and sublethal effects of essential oils from Artemisia khorassanica Podl. and Artemisia sieberi Bess were investigated against adults of Sitotroga cerealella Olivier. To assess the sublethal effects, adult moths were exposed to the LC30 of each essential oil, and life table parameters of the surviving S. cerealella were studied. Higher fumigant toxicity of A. khorassanica (LC50: 7.38 µl/liter air) than A. sieberi (LC50: 9.26 µl/liter air) was observed against S. cerealella. Also, the insecticidal effects of A. khorassanica (LT50: 9.01 h) were faster than A. sieberi (LT50: 14.37 h). A significant extension was observed in the developmental time (egg to adult) of S. cerealella treated with the essential oils. In addition, fecundity of S. cerealella reduced by 25.29 and 35.78% following exposure to sublethal concentrations of A. sieberi and A. khorassanica, respectively. Both tested essential oils caused a significant reduction in the gross and net reproductive rates, intrinsic rate of increase (rm), and finite rate of increase of S. cerealella. The rm values following exposure to A. sieberi, A. khorassanica, and control were 0.098, 0.094, and 0.107 d-1, respectively. The results of this study suggest that tested essential oils have a good potential to apply in integrated pest management of S. cerealella. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  2. Fumigant Toxicity and Sublethal Effects of Artemisia khorassanica and Artemisia sieberi on Sitotroga cerealella (Lepidoptera: Gelechiidae)

    Science.gov (United States)

    Abedi, Z; Abdolmaleki, A; Jafary-Jahed, M; Borzoui, E; Mozaffar Mansouri, Seyed

    2017-01-01

    Abstract Fumigant toxicity and sublethal effects of essential oils from Artemisia khorassanica Podl. and Artemisia sieberi Bess were investigated against adults of Sitotroga cerealella Olivier. To assess the sublethal effects, adult moths were exposed to the LC30 of each essential oil, and life table parameters of the surviving S. cerealella were studied. Higher fumigant toxicity of A. khorassanica (LC50: 7.38 µl/liter air) than A. sieberi (LC50: 9.26 µl/liter air) was observed against S. cerealella. Also, the insecticidal effects of A. khorassanica (LT50: 9.01 h) were faster than A. sieberi (LT50: 14.37 h). A significant extension was observed in the developmental time (egg to adult) of S. cerealella treated with the essential oils. In addition, fecundity of S. cerealella reduced by 25.29 and 35.78% following exposure to sublethal concentrations of A. sieberi and A. khorassanica, respectively. Both tested essential oils caused a significant reduction in the gross and net reproductive rates, intrinsic rate of increase (rm), and finite rate of increase of S. cerealella. The rm values following exposure to A. sieberi, A. khorassanica, and control were 0.098, 0.094, and 0.107 d−1, respectively. The results of this study suggest that tested essential oils have a good potential to apply in integrated pest management of S. cerealella. PMID:29117375

  3. Toxicity and Sublethal Effects of Cantharidin on Musca domestica (Diptera: Muscidae).

    Science.gov (United States)

    Yasoob, Hassan; Ali Khan, Hafiz Azhar; Zhang, Yalin

    2017-09-27

    The house fly, Musca domestica L. (Diptera: Muscidae), is a major pest of medical and veterinary importance all over the world. Management efforts for house flies are usually compromised owing to their resistance to many groups of conventional insecticides. Cantharidin, a natural toxin produced by meloid beetles, is a biopesticide with a reported toxicity to some insect pests including house flies. However, the effects of cantharidin on biological and fitness parameters of house flies have not yet been investigated. In the present study, we investigated the toxicity and sublethal effects of cantharidin on biological parameters of house flies for two consecutive generations. The results revealed that the values of LC50, LC25, LC10, and LC2 against house flies were to be 2.45, 1.23, 0.66, and 0.30 mg/liter, respectively. Sublethal effects of these concentrations on the development and reproduction parameters of house flies revealed that cantharidin reduced population growth by affecting pupation rate, adult emergence, and by lengthening developmental time. The female ratio, fecundity, egg hatching, and survival of adult flies were significantly reduced at LC2, LC10, LC25, and LC50 of cantharidin when compared with the control group. Furthermore, the increase in concentration of cantharidin had a significant effect on reducing the mean values of mean relative growth rate, net reproductive rate (Ro), intrinsic rate of natural increase (rm), and biotic potential (bp). In conclusion, the results of this study revealed the toxicity of cantharidin against house flies and the adverse effects of sublethal concentrations on biological parameters which may have positive implications for effective management of house flies. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. Acute toxicity and sublethal effects of fipronil on detoxification enzymes in juvenile zebrafish (Danio rerio).

    Science.gov (United States)

    Wu, Haihua; Gao, Cuie; Guo, Yaping; Zhang, Yuping; Zhang, Jianzhen; Ma, Enbo

    2014-10-01

    The acute toxicity of fipronil and its sublethal effects on detoxification enzymes (carboxylesterases (CarEs), glutathione S-transferases (GSTs), and 7-ethoxycoumarin O-deethylase (ECOD)) in zebrafish (Danio rerio) were investigated. The results indicated that the 24-h LC50 of fipronil for zebrafish was 220.4 μg/L (95% CI: 173.7-272.4 μg/L). Sublethal concentrations of fipronil did not cause significant changes in CarEs activities. In the liver and muscle tissues, GST activities at the tested concentrations did not significantly differ from those in the control. In the brain and gill tissues, GST activities at a concentration of 4 μg/L were significantly lower than those at a concentration of 2 μg/L. The results suggest that CarEs and GSTs were not suitable biomarkers for fipronil effects in D. rerio. A significant induction in the ECOD activities in the brain, gill, liver, and muscle tissues was observed compared with the control. Moreover, the dose-dependent responses of the ECOD activity were observed after treatment with sublethal concentrations of fipronil in the range of 2-20 μg/L. The results suggested that ECOD could be a suitable biomarker of fipronil effects in D. rerio. Copyright © 2014. Published by Elsevier Inc.

  5. Toxicity, sublethal effects, and potential modes of action of select fungicides on freshwater fish and invertebrates

    Science.gov (United States)

    Elskus, Adria A.

    2012-01-01

    Despite decades of agricultural and urban use of fungicides and widespread detection of these pesticides in surface waters, relatively few data are available on the effects of fungicides on fish and invertebrates in the aquatic environment. Nine fungicides are reviewed in this report: azoxystrobin, boscalid, chlorothalonil, fludioxonil, myclobutanil, fenarimol, pyraclostrobin, pyrimethanil, and zoxamide. These fungicides were identified as emerging chemicals of concern because of their high or increasing global use rates, detection frequency in surface waters, or likely persistence in the environment. A review of the literature revealed significant sublethal effects of fungicides on fish, aquatic invertebrates, and ecosystems, including zooplankton and fish reproduction, fish immune function, zooplankton community composition, metabolic enzymes, and ecosystem processes, such as leaf decomposition in streams, among other biological effects. Some of these effects can occur at fungicide concentrations well below single-species acute lethality values (48- or 96-hour concentration that effects a response in 50 percent of the organisms, that is, effective concentration killing 50 percent of the organisms in 48 or 96 hours) and chronic sublethal values (for example, 21-day no observed adverse effects concentration), indicating that single-species toxicity values may dramatically underestimate the toxic potency of some fungicides. Fungicide modes of toxic action in fungi can sometimes reflect the biochemical and (or) physiological effects of fungicides observed in vertebrates and invertebrates; however, far more studies are needed to explore the potential to predict effects in nontarget organisms based on specific fungicide modes of toxic action. Fungicides can also have additive and (or) synergistic effects when used with other fungicides and insecticides, highlighting the need to study pesticide mixtures that occur in surface waters. For fungicides that partition to

  6. Acute Toxicity and Sublethal Effects of Terpenoids and Essential Oils on the Predator Chrysoperla externa (Neuroptera: Chrysopidae).

    Science.gov (United States)

    Castilhos, R V; Grützmacher, A D; Coats, J R

    2017-07-31

    The search for new safer insecticides has increased in recent agriculture. Botanical compounds such as terpenoids and plant essential oils with insecticidal activity could represent important tools in pest management, and their risk assessment against non-target organisms is necessary since they may serve as a precursor for the synthesis of new insecticide active ingredients. For this study, the acute toxicity and sublethal effects of seven terpenoids and three essential oils with recognized insecticidal activity were evaluated on the predator Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) in laboratory bioassays. Results indicate that these compounds feature relative selectivity to the predator C. externa; however, sublethal effects on reproduction were recorded for some compounds. The phenolic monoterpenoids carvacrol and thymol were more acutely toxic than other terpenoids screened, with LD 50 <20,000 μg/g; however, they were less toxic than natural pyrethrins (toxicity standard) in these bioassays. Sublethal effects on fecundity and fertility were observed for R-(+)-limonene, while oregano oil only affected fecundity. The compounds evaluated here have potential to be used as insecticides and can serve as backbone for future synthesis of selective active ingredients; however, a complete risk assessment to C. externa and other non-target organisms is necessary for their incorporation in future crop protection paradigms.

  7. Toxicity bioassay and effects of sub-lethal exposure of malathion on ...

    African Journals Online (AJOL)

    Clarias gariepinus were exposed to different concentrations of malathion to determine the 96 h LC50 value and its sub-lethal effects on haematological parameters and biochemical composition were also investigated. The 96 h LC50 value concluded was 8.22 mg/L. Specimens of C. gariepinus were exposed to sub-lethal ...

  8. Lethal and Sublethal Toxicity Comparison of BFRs to Three Marine Planktonic Copepods: Effects on Survival, Metabolism and Ingestion.

    Directory of Open Access Journals (Sweden)

    Wenjing Gong

    Full Text Available The estuarine planktonic copepods have a wide geographical distribution and commendable tolerance to various kinds of contaminants. The primary aim of the present study was to contrast the impacts of model POPs (TBBPA and HBCD on three common estuarine planktonic copepods (Oithona similis, Acartia pacifica and Pseudodiaptomus inopinus and establish a protocol for the assessment of acute toxicity of marine organic pollutants. We first quantified the 96h-LC50 (0.566, 0.04 and 0.257 mg/L of TBBPA to the three subjects above respectively and 0.314 mg/L of HBCD to P. inopinus; all reported concentrations are nominal values. In the sub-lethal toxicity tests, it was turned out that the effects of copepods exposed to TBBPA could product different influences on the energy ingestion and metabolism. Different type of pollutions, meanwhile, could also bring varying degree effect on the target copepods. In general, the indicators (the rate of oxygen consumption, ammonia excretion, food ingestion and filtration in higher concentration groups showed marked significant difference compared with controls as well a dose-effect relationship. The study also extended the research on the joint toxicity of TBBPA and HBCD based on the survival rate of P.inopinus. Whether 1:1 concentration or 1:1 toxic level, the research showed synergy effect relative to single exposure conditions. The result indicated that current single ecological testing used for environmental protection activities may underestimate the risk for copepods. It was also demonstrated that short-term sub-lethal experiment could be a standard to evaluate the sensitivity of copepods to POPs.

  9. Temperature and salinity effects on cadmium toxicity on lethal and sublethal responses of Amphibalanus amphitrite nauplii.

    Science.gov (United States)

    Piazza, Veronica; Gambardella, Chiara; Canepa, Sara; Costa, Elisa; Faimali, Marco; Garaventa, Francesca

    2016-01-01

    The official protocol of an ecotoxicological assay employing larvae of the crustacean Amphibalanus amphitrite as a model organism has recently been published by the Italian regulatory authority UNICHIM. Such assay is now one of the applicable tests for water quality assessment under Italian law. While specific temperature and salinity values are recommended by ecotoxicology bioassay protocols for test set up, little information is available on response changes in case of parameter variations. In particular, information is totally lacking for this innovative model organism. Under the standard test protocol, 20°C and 37‰ temperature and salinity, respectively, are required to be set in A. amphitrite bioassay. In order to evaluate the environmental relevance of the test, laboratory experiments simulating the effect on larval responses due to variations of temperature and salinity expected in field collected samples were carried out. The effect of temperature and salinity changes on different end-points, involving increasing sensitivity levels, has been investigated, with and without the presence of cadmium nitrate, Cd(NO3)2, as a reference toxicant, to determine the possible interactions between pollutants and environmental parameters fluctuations. Three end-points - mortality, immobilization, and swimming speed alteration - were measured in order to evaluate the impact of a wide range of temperature (5, 10, 15, 20, 25, 30, 35, 40°C) and salinity values (10, 20, 30, 37, 40, 50, 60, 70‰) on response variation after 24 and 48h of exposure. For each parameter, a Non-Effect Range (NER) - namely the limit values within which no effect related to environmental parameter changes is observed - has been defined. For both parameters, NER resulted to be wider for the less sensitive end-points - such as mortality and immobilization - and for shorter exposure time (24h). Later, the same end-points have been evaluated by exposing the same organisms to a reference toxic

  10. Acute Toxicity and Sublethal Effects of Fenpyroximate to Amblyseius swirskii (Acari: Phytoseiidae).

    Science.gov (United States)

    Lopez, L; Smith, H A; Hoy, M A; Bloomquist, J R

    2015-06-01

    Knowledge about the effects of pesticides on biological control agents is required in order to successfully implement integrated pest management programs. The predatory mite Amblyseius swirskii Athias-Henriot has been used to control thrips, whiteflies, and broad mites in vegetable production; however, effects of fenpyroximate, an acaricide and insecticide used in vegetable crops, on A. swirskii have not been evaluated. The effect of four residual concentrations of fenpyroximate on A. swirskii females was measured under laboratory conditions including its effect on their fecundity and larval survival. Fresh residues of fenpyroximate were significantly toxic to adult females and larvae. Mortality increased and fecundity decreased as the concentration (0.026-0.208 ml/50 ml of water) and time after treatment (24-120 h) increased. Fifty percent of the larvae survived on the two lower concentrations (0.026 and 0.052 ml/50 ml of water) after 120 h. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Toxicity and sub-lethal effect of endemic plants from family Anacardiaceae on oviposition behavior of Aedes albopictus

    Directory of Open Access Journals (Sweden)

    Wan Fatma Zuharah

    2015-08-01

    Conclusions: These results clearly indicate that the acetone extract of G. renghas could be served as potential larvicide, whereas M. fasciculiflora has better sub-lethal effect for oviposition deterrence and against Ae. albopictus as an oviciding agent.

  12. Chronic sublethal effects of San Francisco Bay sediments on nereis (neanthes) arenaceodentata; effect of food ration on sediment toxicity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Moore, D.W.; Dillon, T.M.

    1993-09-01

    This report is designed to address concerns regarding the effect of food ration on toxicity during chronic sublethal sediment bioassays. To this end, a contaminated San Francisco Bay sediment and a clean control sediment were evaluated in a chronic sublethal test under a series of different food rations, with the marine polychaete worm Nereis (Neanthes) arenaceodentata. Animals were exposed from early juvenile stage through the onset of gametogenesis. Treatments were 2.OX, 1.OX, 0.5X, and 0.25X where X is the recommended food ration for laboratory cultures. Test end points were survival, growth, and reproduction. The contaminated sediment was a composite of several cores taken to project depth (38 ft (11.6 m) below mean low water mark) from an area in Oakland Inner Harbor known to be contaminated with polycyclic aromatic hydrocarbons and metals. Comparisons were made with a clean control sediment. The control sediment is used in the laboratory cultures of N. arenaceodentata and was collected from Sequim, WA. Mean percent survival of Neanthes was high (>90 percent) in both the contaminated and control sediment across all food ration treatments. Individual wet weights were significantly reduced with decreasing food ration in both contaminated and control sediments. Significant differences in wet weight between sediment types were observed at the 1.OX, 0.5X, and 0.25X rations. Reproduction (fecundity and emergent juvenile (EJ) production) was also Chronic sublethal, Neanthes, Dredged material, San Francisco Bay, Food ration, Sediment.

  13. A Novel Approach for Predicting Sublethal Effects of Toxicants to Aquatic Organisms

    Science.gov (United States)

    1984-11-30

    organism in concentra- tions ខ.4%. Little or no mortality occurred in other acute tests with the oligochaete, Aeolosoma headleyi, and the cladoceran ...oligochaete, Aeolosoma headlevi, and the cladoceran , Daphnia pulex. Jet fuel WSFs had no discernible effects on microbial communites in 48 h exposures... review (Cairns and van der Schalie 1980) found relatively few biomonitoring techniques in practical use today--perhaps due to cost and lack of legally

  14. Toxicity tests with crustaceans for detecting sublethal effects of potential endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Wollenberger, Leah

    New and updated test methods to detect and characterise endocrine disrupting chemicals are urgently needed for the purpose of environmental risk assessment. Although endocrine disruption in invertebrates has not been studied as extensive as in vertebrates, in particular in fish, numerous reports...... regulated by hormones such as growth, molting, sexual maturation and reproduction. The primary endpoints were larval development ratio, egg production and sex ratio. Exposure experiments were conducted with naturally occurring and synthetic vertebrate and invertebrate hormones as well as compounds known...... to act as endocrine disrupters in vertebrates. Larval development ratio was identified to be a remarkably sensitive endpoint. The larval development test with A. tonsa is rapid, cost-effective, easily to perform and results in full concentration-response relationships allowing the determination...

  15. Biodiversity of soil bacteria exposed to sub-lethal concentrations of phosphonium-based ionic liquids: Effects of toxicity and biodegradation.

    Science.gov (United States)

    Sydow, Mateusz; Owsianiak, Mikołaj; Framski, Grzegorz; Woźniak-Karczewska, Marta; Piotrowska-Cyplik, Agnieszka; Ławniczak, Łukasz; Szulc, Alicja; Zgoła-Grześkowiak, Agnieszka; Heipieper, Hermann J; Chrzanowski, Łukasz

    2018-01-01

    Little is known about the effect of ionic liquids (ILs) on the structure of soil microbial communities and resulting biodiversity. Therefore, we studied the influence of six trihexyl(tetradecyl)phosphonium ILs (with either bromide or various organic anions) at sublethal concentrations on the structure of microbial community present in an urban park soil in 100-day microcosm experiments. The biodiversity decreased in all samples (Shannon's index decreased from 1.75 down to 0.74 and OTU's number decreased from 1399 down to 965) with the largest decrease observed in the microcosms spiked with ILs where biodegradation extent was higher than 80%. (i.e. [P 66614 ][Br] and [P 66614 ][2,4,4]). Despite this general decrease in biodiversity, which can be explained by ecotoxic effect of the ILs, the microbial community in the microcosms was enriched with Gram-negative hydrocarbon-degrading genera e.g. Sphingomonas. It is hypothesized that, in addition to toxicity, the observed decrease in biodiversity and change in the microbial community structure may be explained by the primary biodegradation of the ILs or their metabolites by the mentioned genera, which outcompeted other microorganisms unable to degrade ILs or their metabolites. Thus, the introduction of phosphonium-based ILs into soils at sub-lethal concentrations may result not only in a decrease in biodiversity due to toxic effects, but also in enrichment with ILs-degrading bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Acute toxicity and sublethal effects of the mixture glyphosate (Roundup Active) and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species.

    Science.gov (United States)

    Henao Muñoz, Liliana Marcela; Montes Rojas, Claudia Marsela; Bernal Bautista, Manuel Hernando

    2015-03-01

    Glyphosate is the most widely used herbicide in the world with application in agriculture, forestry, industrial weed control, garden and aquatic environments. However, its use is highly controversial for the possible impact on not-target organisms, such as amphibians, which are vanishing at an alarming and rapid rate. Due to the high solubility in water and ionic nature, the glyphosate requires of surfactants to increase activity. In addition, for the control of coca (Erythroxylum coca) and agricultural weeds in Colombia, formulated glyphosate is mixed and sprayed with the adjuvant Cosmo-Flux 411F to increase the penetration and activity of the herbicide. This study evaluates the acute toxic and sublethal effects (embryonic development, tadpole body size, tadpole swimming performance) of the mixture of the formulated glyphosate Roundup Active and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species under 96h laboratory standard tests and microcosms, which are more similar to field conditions as they include soil, sand and macrophytes. In the laboratory, embryos and tadpoles of Engystomops pustulosus were the most tolerant (LC50 = 3904 microg a.e./L; LC50=2 799 pg a.e./L, respectively), while embryos and tadpoles of Hypsiboas crepitans (LC50=2 203 microg a.e./L; LC50=1424 microgg a.e./L, respectively) were the most sensitive. R. humboldti and R. marina presented an intermediate toxicity. Embryos were significantly more tolerant to the mixture than tadpoles, which could be likely attributed to the exclusion of chemicals by the embryonic membranes and the lack of organs, such as gills, which are sensitive to surfactants. Sublethal effects were observed for the tadpole body size, but not for the embryonic development and tadpole swimming performance. In microcosms, no toxicity (LC50 could not be estimated), or sublethal responses were observed at concentrations up to fourfold (14.76 kg glyphosate a.e./ha) the highest field application rate of 3

  17. Toxicity and sublethal effects of chlorantraniliprole on the development and fecundity of a non-specific predator, the multicolored Asian lady beetle, Harmonia axyridis (Pallas).

    Science.gov (United States)

    Nawaz, Muhammad; Cai, Wanlun; Jing, Zhao; Zhou, Xingmiao; Mabubu, Juma Ibrahim; Hua, Hongxia

    2017-07-01

    In order to further develop integrated pest management (IPM) approaches for controlling insect pests, it is important to estimate the effects of pesticides. In this study, the toxicity and sublethal effects of the insecticide chlorantraniliprole on a non-specific predator, the multicolored Asian lady beetle Harmonia axyridis, were evaluated and life table parameter data were analyzed statistically using the age-stage, two-sex life table procedure. The results of this study show that the development time of second and fourth instar larvae as well as pupa was significantly prolonged in populations treated with LC10 (2.42 mg (a.i.) L -1 ) and LC30 (12.06 mg (a.i.) L -1 ), while adult longevity and fecundity were both significantly reduced and the preoviposition period (POP) was significantly prolonged following treatment compared to the control. In addition, the net reproductive rate (R 0 ), as well as the intrinsic (r) and finite rate of increase (λ) were significantly decreased in groups treated with the insecticide. These results reveal that because sublethal concentrations of chlorantraniliprole impair the population growth of H. axyridis, more attention should be paid to the use of this chemical as a component of IPM strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Histopathological effects of lethal and sub-lethal concentrations of ...

    African Journals Online (AJOL)

    The histopathological effects of lethal and sub-lethal concentrations of glyphosate on African catfish Clarias gariepinus were investigated. C. gariepinus juveniles were assessed in a static renewal bioassay for 96 hours (acute toxicity) and 28 days (chronic toxicity) using varying concentrations (0.0 mg/l 20.0 mg/l, 30.0 mg/l, ...

  19. Sublethal toxicity and biotransformation of pyrene in Lumbriculus variegatus (Oligochaeta)

    Energy Technology Data Exchange (ETDEWEB)

    Maeenpaeae, K. [Faculty of Biosciences, University of Joensuu, FIN-80101 Joensuu (Finland)], E-mail: kimmo.maenpaa@joensuu.fi; Leppaenen, M.T.; Kukkonen, J.V.K. [Faculty of Biosciences, University of Joensuu, FIN-80101 Joensuu (Finland)

    2009-04-01

    The aim of this work was to study the toxicity and biotransformation of polyaromatic hydrocarbon (PAH) pyrene in the oligochaete aquatic worm, Lumbriculus variegatus. PAHs are ubiquitous environmental pollutants that pose a hazard to aquatic organisms, and metabolizing capability is poorly known in the case of many invertebrate species. To study the toxicity and biotransformation of pyrene, the worm was exposed for 15 days to various concentrations of water-borne pyrene. The dorsal blood vessel pulse rate was used as a sublethal endpoint. Pyrene biotransformation by L. variegatus was studied and the critical body residues (CBR) were estimated for pyrene toxicity. The toxicokinetics of pyrene uptake was evaluated. A combination of radiolabeled ({sup 14}C) and nonlabeled pyrene was used in the exposures, and liquid scintillation counting (LSC) and high-pressure liquid chromatography were employed in both water and tissue residue analyses. The results showed that L. variegatus was moderately able to metabolize pyrene to 1-hydroxypyrene (1-HP), thus demonstrating that the phase-I-like oxidizing enzyme system metabolizes pyrene in L. variegatus. The amount of the 1-HP was 1-2% of the amount of pyrene in the worm tissues. The exposure to pyrene reduced the blood vessel pulse rate significantly (p < 0.05), showing that pyrene had a narcotic effect. The estimated CBRs remained constant during the exposure time, varying from 0.120 to 0.174 mmol pyrene/kg worm wet weight. The bioconcentration factors (BCF) decreased as exposure concentration increased. It was suggested that the increased toxicity of pyrene accounted for the decrease in BCFs by lowering the activity of the organism.

  20. Sublethal haematological effects of zinc on the freshwater fish ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... industrial and domestic wastes water discharges and animals where it ... that zinc could cause sub-acute effects that change fish behaviours. ... These include the sublethal effects of concentrations of water extracts of akee apple on C. gariepinus (Onusiriuka and Ufodike, 1998). Toxicity of cas- sava leaf ...

  1. Identification of sublethal toxicants in a BC coastal pulp and paper mill effluent

    Energy Technology Data Exchange (ETDEWEB)

    Eickhoff, C.V.; Pickard, J.; Kinnee, K. [BC Research Inc., Vancouver, BC (Canada); Dwernychuk, W. [Hatfield Consultants Ltd., West Vancouver, BC (Canada); Birkholz, D. [EnviroTest Lab., Edmonton, AB (Canada); Kilback, D. [Pacifica Papers, Powell River, BC (Canada)

    2001-06-01

    BC Research Inc. conducted a toxicity identification evaluation to identify the different compounds comprised in the mill Outfall number 1 effluent. The Environmental Effects Monitoring program had determined that these compounds were responsible for sublethal effects to organisms. Echinoderm species like the sand dollar, Dendraster excentricus Eshscholtz, the purple sea urchin, Stronglyocentrotus purpuratus Stimpson, and the marine algae, Champia parvula had suffered toxicity caused by the mill effluent. The last several Environmental Effects Monitoring testing periods had shown the sublethal toxicity of the Outfall number 1 effluent to echinoderms was very consistent. Based on the high cost and shipping associated with the Champia bioassays, toxicity tests conducted during the peak spawning season of the sea urchin and the non significant difference between the sensitivity of the sand dollar and the purple sea urchin, the purple sea urchin was selected to evaluate the toxicity of the manipulated samples for the tests. The tests conducted were: a baseline toxicity test performed immediately upon receipt of the effluent sample, the pH adjustment filtration test to determine if the toxic compound can be removed using filtration, the pH adjustment aeration test to determine if volatile compounds in the sample are toxic, the pH adjustment solid phase extraction test to determine the level of toxicity from organic compounds and metal chelates that can be removed by solid phase extraction. The results indicated that it seems high molecular weight molecules were responsible for the sublethal toxicity observed. Two different sources could be responsible: lignin derived macromolecules, and polymer compounds used as flocculants and sizing agents. Further testing of the pulp mill effluent to identify the source of the toxic high molecular weight compounds was recommended. 22 refs., 4 tabs., 6 figs.

  2. Toxicity of insecticides to Toxorhynchites splendens and three vector mosquitos and their sublethal effect on biocontrol potential of the predator.

    Science.gov (United States)

    Amalraj, D D; Das, P K

    1996-03-01

    Toxicity of six larvicides ie fenthion, temephos, malathion, deltamethrin, alphamethrin (Fendona), OMS 3031 and five adulticides ie malathion, fenitrothion, propoxur, deltamethrin, permethrin to Aedes aegypti, Culex quiquefasciatus, Anopheles stephensi and the predator, Toxorhynchites splendens was studied for evaluating safety margin. Concentrations of alphamethrin that killed 50% larvae of T. splendens were 53 and 12 times more than that which killed Cx. quinquefasciatus and Ae. aegypti. In case of deltamethrin, concentrations required to kill 50% larvae of T. splendens were 14 and 5 times more than that required against other two species. Other larvicides tested were equally toxic to both T. splendens and vector mosquitos. There was no significant difference in the toxicity of larvicides to T. splendens and An. stephensi. Deltamethrin was 25-132 times less toxic to adults of T. splendens in comparison to vector mosquitos. For other adulticides the range was 1-10. Immature developmental time of T. splendens was not affected by any of the insecticides tested. However, predation rate was lowered when larvae of Ae. aegypti previously exposed to fenthion and temephos were offered. Whereas, alphamethrin and OMS 3031 did not affect the feeding rate of the predator. There was a significant reduction in the pupal weight and pupation as a result of the predator feeding on the insecticide treated prey. There was a significant negative relationship between rate of pupation and dosage. The present study indicates that synthetic pyrethroids owing to their higher safety margin can be used in an integrated vector management program.

  3. Pesticides and Arthropods: Sublethal Effects and Demographic Toxicology

    Directory of Open Access Journals (Sweden)

    Dejan Marčić

    2007-01-01

    Full Text Available Insecticides and acaricides designed to control primary harmful insects and mites may also variously affect some other arthopods present in an (agroecosystem (e.g. secondary pests, predators, parasitoids, saprophytes, bioindicators, pollinators. Apart from insecticides and acaricides, arthropods may also be affected by the activity of other pesticides (fungicides, herbicides, etc.. Regardless of whether they are deemed desirable or not, the effects that pesticides have on arthopods need to be quantified as closely as possible through appropriate experimental procedures. Data acquired in tests designed to determined LD50/LC50 values are inadequate for evaluation of pesticide effectiveness in the field as pesticidesalso cause various sublethal effects, generally disregarded in such investigations. The sublethal effects of pesticides refer to any altered behaviour and/or physiology of individuals that have survived exposure to pesticides at doses/concentrations that can be lethal(within range causing mortality in an experimental population that exceeds mortality in an untreated population or sublethal (below that range. Pesticides affect locomotion and mobility, stimulate dispersion of arthropods from treated areas, complicate or prevent their navigation, orientation and ability to locate hosts, and cause changes in their feeding, mating and egg-laying patterns. Sublethal pesticide effects on arthropod physiology reflect on the life span, rate of development, fecundity and/or fertility, sex ratio and immunity of surviving individuals. Different parameters are being used in arthropod bioassays to determine sublethal effects (ED50/EC50, LOEC, NOEC, total effect index. Compared to acute toxicity tests, these parameters improve the quality of evaluation and create a more accurate view of the effects of a pesticide. However, such approach covers mainly fecundity/fertility alone, while all other sublethal effects remain unaccounted for. Besides, it

  4. A comparison of the sublethal and lethal toxicity of four pesticides in Hyalella azteca and Chironomus dilutus.

    Science.gov (United States)

    Hasenbein, Simone; Connon, Richard E; Lawler, Sharon P; Geist, Juergen

    2015-08-01

    Laboratory toxicity testing is the primary tool used for surface water environmental risk assessment; however, there are critical information gaps regarding the sublethal effects of pesticides. In 10-day exposures, we assessed the lethal and sublethal (motility and growth) toxicities of four commonly used pesticides, bifenthrin, permethrin, cyfluthrin, and chlorpyrifos, on two freshwater invertebrates, Chironomus dilutus and Hyalella azteca. Pyrethroids were more toxic than the organophosphate chlorpyrifos in both species. Bifenthrin was most toxic to H. azteca survival and growth. Cyfluthrin was most toxic to C. dilutus. However, cyfluthrin had the greatest effect on motility on both H. azteca and C. dilutus. The evaluated concentrations of chlorpyrifos did not affect C. dilutus motility or growth, but significantly impacted H. azteca growth. Motility served as the most sensitive endpoint in assessing sublethal effects at low concentrations for both species, while growth was a good indicator of toxicity for all four pesticides for H. azteca. The integration of sublethal endpoints in ambient water monitoring and pesticide regulation efforts could improve identification of low-level pesticide concentrations that may eventually cause negative effects on food webs and community structure in aquatic environments.

  5. Effects of salinity on short-term waterborne zinc uptake, accumulation and sub-lethal toxicity in the green shore crab (Carcinus maenas)

    Energy Technology Data Exchange (ETDEWEB)

    Niyogi, Som, E-mail: som.niyogi@usask.ca [Department of Biology, University of Saskatchewan, Saskatoon, SK (Canada); Toxicology Centre, University of Saskatchewan, Saskatoon, SK (Canada); Bamfield Marine Sciences Centre, Bamfield, BC (Canada); Blewett, Tamzin A. [Bamfield Marine Sciences Centre, Bamfield, BC (Canada); Department of Biological Sciences, University of Alberta, Edmonton, AB (Canada); Department of Biology, McMaster University, Hamilton, ON (Canada); Gallagher, Trevor [Toxicology Centre, University of Saskatchewan, Saskatoon, SK (Canada); Fehsenfeld, Sandra [Bamfield Marine Sciences Centre, Bamfield, BC (Canada); Department of Biological Sciences, University of Manitoba, Winnipeg, MB (Canada); Department of Zoology, University of British Columbia, Vancouver, BC (Canada); Wood, Chris M. [Bamfield Marine Sciences Centre, Bamfield, BC (Canada); Department of Biology, McMaster University, Hamilton, ON (Canada); Department of Zoology, University of British Columbia, Vancouver, BC (Canada)

    2016-09-15

    Highlights: • Zinc accumulation in the euryhaline green crab is partially salinity dependent. • Zinc accumulates mainly in the gills of green crab during acute waterborne exposure. • Branchial zinc and calcium transport in the green crab occurs via a common pathway. • Acute waterborne Zn exposure disrupts calcium and zinc homeostasis in the green crab. - Abstract: Waterborne zinc (Zn) is known to cause toxicity to freshwater animals primarily by disrupting calcium (Ca) homeostasis during acute exposure, but its effects in marine and estuarine animals are not well characterized. The present study investigated the effects of salinity on short-term Zn accumulation and sub-lethal toxicity in the euryhaline green shore crab, Carcinus maenas. The kinetic and pharmacological properties of short-term branchial Zn uptake were also examined. Green crabs (n = 10) were exposed to control (no added Zn) and 50 μM (3.25 mg L{sup −1}) of waterborne Zn (∼25% of 96 h LC{sub 50} in 100 seawater) for 96 h at 3 different salinity regimes (100%, 60% and 20% seawater). Exposure to waterborne Zn increased tissue-specific Zn accumulation across different salinities. However, the maximum accumulation occurred in 20% seawater and no difference was recorded between 60% and 100% seawater. Gills appeared to be the primary site of Zn accumulation, since the accumulation was significantly higher in the gills relative to the hepatopancreas, haemolymph and muscle. Waterborne Zn exposure induced a slight increase in haemolymph osmolality and chloride levels irrespective of salinity. In contrast, Zn exposure elicited marked increases in both haemolymph and gill Ca levels, and these changes were more pronounced in 20% seawater relative to that in 60% or 100% seawater. An in vitro gill perfusion technique was used to examine the characteristics of short-term (1–4 h) branchial Zn uptake over an exposure concentration range of 3–12 μM (200–800 μg L{sup −1}). The rate of short

  6. Biodiversity of soil bacteria exposed to sub-lethal concentrations of phosphonium-based ionic liquids: Effects of toxicity and biodegradation

    DEFF Research Database (Denmark)

    Sydow, Mateusz; Owsianiak, Mikołaj; Framski, Grzegorz

    2018-01-01

    Little is known about the effect of ionic liquids (ILs) on the structure of soil microbial communities and resulting biodiversity. Therefore, we studied the influence of six trihexyl(tetradecyl)phosphonium ILs (with either bromide or various organic anions) at sublethal concentrations...... on the structure of microbial community present in an urban park soil in 100-day microcosm experiments. The biodiversity decreased in all samples (Shannon's index decreased from 1.75 down to 0.74 and OTU's number decreased from 1399 down to 965) with the largest decrease observed in the microcosms spiked with ILs...... where biodegradation extent was higher than 80%. (i.e. [P66614][Br] and [P66614][2,4,4]). Despite this general decrease in biodiversity, which can be explained by ecotoxic effect of the ILs, the microbial community in the microcosms was enriched with Gram-negative hydrocarbon-degrading genera e...

  7. Acute toxicity and sublethal effects of the mixture glyphosate (Roundup® Active and Cosmo-Flux®411F to anuran embryos and tadpoles of four Colombian species

    Directory of Open Access Journals (Sweden)

    Liliana Marcela Henao Muñoz

    2015-03-01

    Full Text Available Glyphosate is the most widely used herbicide in the world with application in agriculture, forestry, industrial weed control, garden and aquatic environments. However, its use is highly controversial for the possible impact on not-target organisms, such as amphibians, which are vanishing at an alarming and rapid rate. Due to the high solubility in water and ionic nature, the glyphosate requires of surfactants to increase activity. In addition, for the control of coca (Erythroxylum coca and agricultural weeds in Colombia, formulated glyphosate is mixed and sprayed with the adjuvant Cosmo-Flux®411F to increase the penetration and activity of the herbicide. This study evaluates the acute toxic and sublethal effects (embryonic development, tadpole body size, tadpole swimming performance of the mixture of the formulated glyphosate Roundup® Active and Cosmo-Flux®411F to anuran embryos and tadpoles of four Colombian species under 96h laboratory standard tests and microcosms, which are more similar to field conditions as they include soil, sand and macrophytes. In the laboratory, embryos and tadpoles of Engystomops pustulosus were the most tolerant (LC50=3 904µg a.e./L; LC50=2 799µg a.e./L, respectively, while embryos and tadpoles of Hypsiboas crepitans (LC50=2 203µg a.e./L; LC50=1 424µg a.e./L, respectively were the most sensitive. R. humboldti and R. marina presented an intermediate toxicity. Embryos were significantly more tolerant to the mixture than tadpoles, which could be likely attributed to the exclusion of chemicals by the embryonic membranes and the lack of organs, such as gills, which are sensitive to surfactants. Sublethal effects were observed for the tadpole body size, but not for the embryonic development and tadpole swimming performance. In microcosms, no toxicity (LC50 could not be estimated, or sublethal responses were observed at concentrations up to fourfold (14.76kg glyphosate a.e./ha the highest field application rate of 3

  8. Modeling Population and Ecosystem Response to Sublethal Toxicant Exposure

    Science.gov (United States)

    2000-09-30

    Award No. N000149910024 http://lifesci.ucsb.edu/EEMB/faculty/nisbet LONG TERM GOALS The ecological effects of environmental stress occur within complex...those of real populations. We have also investigated how toxicants may affect the stability of the system. If the toxicant effect is primarily an...will be submitted in the near future. IMPACT/APPLICATIONS Our DEB modeling work aims to unify theory describing the effects of environmental stress on

  9. Use of sublethal endpoints in sediment toxicity tests with the amphipod Hyalella azteca

    Science.gov (United States)

    Ingersoll, Chris G.; Brunson, Eric L.; Dwyer, F. James; Hardesty, Douglas K.; Kemble, Nile E.

    1998-01-01

    Short-term sediment toxicity tests that only measure effects on survival can be used to identify high levels of contamination but may not be able to identify marginally contaminated sediments. The objective of the present study was to develop a method for determining the potential sublethal effects of contaminants associated with sediment on the amphipod Hyalella azteca (e.g., reproduction). Exposures to sediment were started with 7- to 8-d-old amphipods. On day 28, amphipods were isolated from the sediment and placed in water-only chambers where reproduction was measured on day 35 and 42. Typically, amphipods were first in amplexus at about day 21 to 28 with release of the first brood between day 28 to 42. Endpoints measured included survival (day 28, 35, and 42), growth (as length and weight on day 28 and 42), and reproduction (number of young/female produced from day 28 to 42). This method was used to evaluate a formulated sediment and field-collected sediments with low to moderate concentrations of contaminants. Survival of amphipods in these sediments was typically >85% after the 28-d sediment exposures and the 14-d holding period in water to measure reproduction. Reproduction was more variable than growth; hence, more replicates might be needed to establish statistical differences among treatments. Previous studies have demonstrated that growth of H. azteca in sediment tests often provides unique information that can be used to discriminate toxic effects of exposure to contaminants. Either length or weight can be measured in sediment tests with H. azteca. However, additional statistical options are available if length is measured on individual amphipods, such as nested analysis of variance that can account for variance in length within replicates. Ongoing water-only studies testing select contaminants will provide additional data on the relative sensitivity and variability of sublethal endpoints in toxicity tests with H. azteca.

  10. Effects of sublethal concentrations of formalin on weight gain in the ...

    African Journals Online (AJOL)

    The African Catfish, Clarias gariepinus, was exposed to various sublethal concentrations (25.0, 12.50, 6.25, 3.125, 1.56 and 0.0 mgl-1) of formalin to investigate their effects on the weight gain of the fish. Decrease in weight gain, directly proportional to the toxicant concentration, was observed in fish exposed to ...

  11. Effects of nanomolar copper on water plants—Comparison of biochemical and biophysical mechanisms of deficiency and sublethal toxicity under environmentally relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, George, E-mail: george.thomas@uni.kn [Universität Konstanz, Mathematisch-Naturwissenschaftliche Sektion, Fachbereich Biologie, D-78457 Konstanz (Germany); Stärk, Hans-Joachim, E-mail: ha-jo.staerk@ufz.de [UFZ – Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstr. 15, D-04318 Leipzig (Germany); Wellenreuther, Gerd, E-mail: Gerd.wellenreuther@desy.de [HASYLAB at DESY, Notkestr. 85, 22603 Hamburg (Germany); Dickinson, Bryan C., E-mail: bryan.dickinson@gmail.com [Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, MA 02138 (United States); Küpper, Hendrik, E-mail: hendrik.kuepper@uni-konstanz.de [Universität Konstanz, Mathematisch-Naturwissenschaftliche Sektion, Fachbereich Biologie, D-78457 Konstanz (Germany); University of South Bohemia, Faculty of Biological Sciences and Institute of Physical Biology, Branišovská 31, CZ-370 05 České Budejovice (Czech Republic)

    2013-09-15

    Highlights: •We found different optimal Cu requirement for different physiological mechanisms. •Kinetics and concentration thresholds of damage mechanisms were established. •Cu toxicity caused internal Cu re-distribution and inhibition of Zn uptake. •Cu deficient plants released Cu, indicating lack of high-affinity Cu transporters. •Cu deficiency caused re-distribution of zinc in the plant. -- Abstract: Toxicity and deficiency of essential trace elements like Cu are major global problems. Here, environmentally relevant sub-micromolar concentrations of Cu (supplied as CuSO{sub 4}) and simulations of natural light- and temperature cycles were applied to the aquatic macrophyte Ceratophyllum demersum. Growth was optimal at 10 nM Cu, while PSII activity (F{sub v}/F{sub m}) was maximal around 2 nM Cu. Damage to the PSII reaction centre was the first target of Cu toxicity, followed by disturbed regulation of heat dissipation (NPQ). Only after that, electron transport through PSII (Φ{sub PSII}) was inhibited, and finally chlorophylls decreased. Copper accumulation in the plants was stable until 10 nM Cu in solution, but strongly increased at higher concentrations. The vein was the main storage site for Cu up to physiological concentrations (10 nM). At toxic levels it was also sequestered to the epidermis and mesophyll until export from the vein became inhibited, accompanied by inhibition of Zn uptake. Copper deficiency led to a complete stop of growth at “0” nM Cu after 6 weeks. This was accompanied by high starch accumulation although electron flow through PSII (Φ{sub PSII}) decreased from 2 weeks, followed by decrease in pigments and increase of non photochemical quenching (NPQ). Release of Cu from the plants below 10 nM Cu supply in the nutrient solution indicated lack of high-affinity Cu transporters, and on the tissue level copper deficiency led to a re-distribution of zinc.

  12. Sublethal effects of imidacloprid on interactions in a tritrophic system of non-target species.

    Science.gov (United States)

    Uhl, Philipp; Bucher, Roman; Schäfer, Ralf B; Entling, Martin H

    2015-08-01

    Imidacloprid is one of the most used insecticides worldwide, but is highly toxic to non-target arthropods. Effects of sublethal imidacloprid intoxication can potentially propagate in food webs, yet little is known about the impact on non-target populations and communities. We investigated short-term sublethal toxicity of imidacloprid in a tritrophic model system of wild strawberry Fragaria vesca, wood cricket Nemobius sylvestris and nursery web spider Pisaura mirabilis. Strawberries were treated two times with 0mg (control), 1mg (low rate) and 10mg (high rate) of Confidor® WG 70 and crickets were allowed to feed on them. In four lab experiments, we quantified the impact of imidacloprid on leaf damage, growth, behaviour and survival of crickets. The high imidacloprid rate reduced feeding, mass gain, thorax growth and mobility in crickets compared to the control, while mortality was similarly low in all treatments. The low rate reduced mass gain only. Cricket survival of spider predation was higher in the low rate treatment than in the control. Overall, herbivory and predation were reduced at sublethal imidacloprid rates in a non-target organism, three-level food chain, which demonstrates possible propagation of sublethal effects through trophic interactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Intramuscular Cobinamide Sulfite in a Rabbit Model of Sub-Lethal Cyanide Toxicity

    Science.gov (United States)

    Brenner, Matthew; Kim, Jae G.; Mahon, Sari B.; Lee, Jangwoen; Kreuter, Kelly A.; Blackledge, William; Mukai, David; Patterson, Steve; Mohammad, Othman; Sharma, Vijay S.; Boss, Gerry R.

    2009-01-01

    Objective To determine the ability of an intramuscular cobinamide sulfite injection to rapidly reverse the physiologic effects of cyanide toxicity. Background Exposure to cyanide in fires and industrial exposures and intentional cyanide poisoning by terrorists leading to mass casualties is an ongoing threat. Current treatments for cyanide poisoning must be administered intravenously, and no rapid treatment methods are available for mass casualty cyanide exposures. Cobinamide is a cobalamin (vitamin B12) analog with an extraordinarily high affinity for cyanide that is more water-soluble than cobalamin. We investigated the use of intramuscular cobinamide sulfite to reverse cyanide toxicity induced physiologic changes in a sublethal cyanide exposure animal model. Methods New Zealand white rabbits were given 10 mg sodium cyanide intravenously over 60 minutes. Quantitative diffuse optical spectroscopy and continuous wave near infrared spectroscopy monitoring of tissue oxy- and deoxyhemoglobin concentrations were performed concurrently with blood cyanide level measurements and cobinamide levels. Immediately after completion of the cyanide infusion, the rabbits were injected intramuscularly with cobinamide sulfite (n=6) or inactive vehicle (controls, n=5). Results Intramuscular administration led to rapid mobilization of cobinamide and was extremely effective at reversing the physiologic effects of cyanide on oxyhemoglobin and deoxyhemoglobin extraction. Recovery time to 63% of their baseline values in the central nervous system was in a mean of 1032 minutes in the control group and 9 minutes in the cobinamide group with a difference of 1023 minutes (95% confidence interval [CI] 116, 1874 minutes). In muscle tissue, recovery times were 76 and 24 minutes with a difference of 52 minutes (95% CI 7, 98min). Red blood cell cyanide levels returned towards normal significantly faster in cobinamide sulfite-treated animals than in control animals. Conclusions Intramuscular

  14. Lethal and sublethal toxicity of the industrial chemical epichlorohydrin on Rhinella arenarum (Anura, Bufonidae) embryos and larvae.

    Science.gov (United States)

    Hutler Wolkowicz, Ianina R; Aronzon, Carolina M; Pérez Coll, Cristina S

    2013-12-15

    Lethal and sublethal toxicity of the major chemical used in epoxide compounds, epichlorohydrin (ECH) was evaluated on the early life cycle of the common South American toad, Rhinella arenarum (Anura, Bufonidae). The stages evaluated were (according to Del Conte and Sirlin): early blastula (S.3-S.4), gastrula (S.10-S.12), rotation (S.15), tail bud (S.17), muscular response (S.18), gill circulation (S.20), open mouth (S.21), opercular folds (S.23) and complete operculum (S.25). The LC50 and EC50 values for lethal and sublethal effects were calculated. The early blastula was the most sensitive stage to ECH both for continuously and pulse-exposures (LC50-24h=50.9 mg L(-1)), while S.20 was the most resistant (LC50-24h=104.9 mg L(-1)). Among sublethal effects, early blastula was also the most sensitive stage (LOEC-48 h=20 mg L(-1)) and it has a Teratogenic Index of 2.5, which indicates the teratogenic potential of the substance. The main abnormalities were persistent yolk plugs, cell dissociation, tumors, hydropsy, oral malformations, axial/tail flexures, delayed development and reduced body size. ECH also caused neurotoxicity including scarce response to stimuli, reduction in the food intake, general weakness, spasms and shortening, erratic or circular swimming. Industrial contamination is considered an important factor on the decline of amphibian populations. Considering the available information about ECH's toxicity and its potential hazard to the environment, this work shows the first results of its developmental toxicity on a native amphibian species, Rhinella arenarum. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Sublethal Effects of Thiamethoxam on the Demographic Parameters of Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Wang, Pan; Zhou, Li-Lin; Yang, Fan; Li, Mang; Liu, Xiao-Ming; Wang, Yong; Lei, Chao-Liang; Si, Sheng-Yun

    2017-08-01

    The green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), is an important sap-sucking pest of many crops, including Chinese cabbage, Brassinca oleracea L. The neonicotinoid insecticide thiamethoxam has been used as an effective insecticide to control M. persicae in cabbage fields. In this study, we assessed the effects of sublethal concentrations of thiamethoxam on demographic parameters of M. persicae. In leaf-dip bioassays, thiamethoxam showed a relatively high toxicity against M. persicae with an LC50 of 6.80 mg liter-1. The duration of the preadult stage was not significantly affected in the sublethal bioassay. Additionally, the longevity and adult preoviposition period were not significantly affected by sublethal thiamethoxam. However, sublethal thiamethoxam significantly increased fecundity (LC10) and prolonged the total preoviposition period (LC40). Consequently, the finite rate of increase (λ) and the intrinsic rate of increase (rm) of aphids exposed to the LC40 were significantly lower than those of control aphids, whereas the net reproductive rate (R0) was higher, and the generation time (T) and the population doubling time (DT) were longer in the treated group. Based on these results, hormesis was induced by sublethal thiamethoxam in M. persicae, with the population growth of M. persicae negatively affected at higher sublethal concentrations of thiamethoxam. Therefore, our study indicated that the possible effects of thiamethoxam on aphids require further study to develop optimized integrated pest management strategies. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Sublethal effects of manganese on the haematology and ...

    African Journals Online (AJOL)

    Information concerning the sublethal effects of pollutants, such as metals, forms an integral part of ecosystem health assessment programmes and of procedures followed to develop water quality guidelines for environmetal protection. The data from this study were incorporated into a water quality index (RAUWaterz) ...

  17. Effects of sublethal doses of chlorfluazuron on the ovarian ...

    African Journals Online (AJOL)

    Therefore, it is concluded that sublethal doses of chlorfluazuron reduced the amounts of ovarian constituents during ovarian development and oogenesis in S. litura. These reductions increased with an increase in dose from LD10 to LD30. The effects of chlorfluazuron on the amounts of ovarian constituents are presumed to ...

  18. Review: Sublethal effects of temperature on freshwater organisms ...

    African Journals Online (AJOL)

    Review: Sublethal effects of temperature on freshwater organisms, with special reference to aquatic insects. HF Dallas, V Ross-Gillespie. Abstract. Water temperature is a key variable affecting aquatic organisms. Understanding their response to elevated water temperatures is important for estimating upper thermal limits, ...

  19. Sublethal effects of carbaryl on embryonic and gonadal ...

    African Journals Online (AJOL)

    Sex reversal was delayed in the experimental groups, with a sex ratio of 13 females to 0 males, but the control group recorded 6 females to 8 males. These results suggest that sublethal doses of carbaryl in the environment, similar to those used in the current study, may have an adverse effect on the reproductive success of ...

  20. Sublethal mechanisms of Pb and Zn toxicity to the purple sea urchin (Strongylocentrotus purpuratus) during early development.

    Science.gov (United States)

    Tellis, Margaret S; Lauer, Mariana M; Nadella, Sunita; Bianchini, Adalto; Wood, Chris M

    2014-01-01

    In order to understand sublethal mechanisms of lead (Pb) and zinc (Zn) toxicity, developing sea urchins were exposed continuously from 3h post-fertilization (eggs) to 96 h (pluteus larvae) to 55 (±2.4) μgPb/L or 117 (±11)μgZn/L, representing ~ 70% of the EC50 for normal 72 h development. Growth, unidirectional Ca uptake rates, whole body ion concentrations (Na, K, Ca, Mg), Ca(2+) ATPase activity, and metal bioaccumulation were monitored every 12h over this period. Pb exhibited marked bioaccumulation whereas Zn was well-regulated, and both metals had little effect on growth, measured as larval dry weight, or on Na, K, or Mg concentrations. Unidirectional Ca uptake rates (measured by (45)Ca incorporation) were severely inhibited by both metals, resulting in lower levels of whole body Ca accumulation. The greatest disruption occurred at gastrulation. Ca(2+) ATPase activity was also significantly inhibited by Zn but not by Pb. Interestingly, embryos exposed to Pb showed some capacity for recovery, as Ca(2+)ATPase activities increased, Ca uptake rates returned to normal intermittently, and whole body Ca levels were restored to control values by 72-96 h of development. This did not occur with Zn exposure. Both Pb and Zn rendered their toxic effects through disruption of Ca homeostasis, though likely through different proximate mechanisms. We recommend studying the toxicity of these contaminants periodically throughout development as an effective way to detect sublethal effects, which may not be displayed at the traditional toxicity test endpoint of 72 h. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Sublethal dietary effects of Microcystis on Sacramento splittail, Pogonichthys macrolepidotus.

    Science.gov (United States)

    Acuña, Shawn; Deng, Dong-Fang; Lehman, Peggy; Teh, Swee

    2012-04-01

    The presence of the toxic cyanobacterium Microcystis in the upper San Francisco Estuary (SFE) since 1999 is a potential but to date an unquantified threat to the health and survival of aquatic organisms, such as fish and zooplankton. The microcystins (MCs) predominantly in the LR-form (MC-LR) contained in Microcystis is hepatotoxic and a potential threat to the fishery. This study was conducted to determine the effects of dietary exposure of the endemic Sacramento splittail, Pogonichthys macrolepidotus in SFE to Microcystis and its toxin, MC-LR. Juvenile splittail (12.59 ± 0.7 g fish(-1)) were exposed to five diets for 28 d with MC-LR obtained from: (1) Microcystis harvested from the SFE and (2) a synthetic purified form of MC-LR. Three of the test diets contained 3.55 (D5), 9.14 (D10) and 17.13 (D20)mg MC-LR kg(-1) from Microcystis. The other two diets contained either purified MC-LR at 3.89 mg MC-LR kg(-1) (D5R) or no MC-LR (D0). The RNA/DNA ratio of fish muscle was significantly lower for all treatments fed test diets containing MC-LR compared to the control diet D0, suggesting Microcystis adversely affected nutritional status. Protein phosphatase 2A expression in the fish from the D5, D10 and D20 treatments were inversely affected by increasing concentrations of MC-LR. Cytoplasmic inclusion bodies and single cell necrosis were more prevalent and greater in severity in the fish exposed to the diets D10 and D20 compared to fish from the D0 treatment and indicate severe liver toxicity in splittail exposed to MC-LR. The sublethal effects on splittail characterized by this study suggest cyanobacterial blooms have the potential to affect splittail nutritional status and health in SFE. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Chloride and sulphate toxicity to Hydropsyche exocellata (Trichoptera, Hydropsychidae): Exploring intraspecific variation and sub-lethal endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Sala, Miquel [Centre Tecnològic Forestal de Catalunya - CTFC, Solsona, Catalunya (Spain); Faria, Melissa [CESAM, Departamento de Biologia, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Sarasúa, Ignacio [Technische Universität München, Munich, Bayern (Germany); Barata, Carlos [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona (Spain); Bonada, Núria [Grup de Recerca Freshwater Ecology and Management (FEM), Departament d' Ecologia, Facultat de Biologia, Universitat de Barcelona (UB), Diagonal 643, 08028 Barcelona, Catalonia (Spain); Grup de Recerca Freshwater Ecology and Management (FEM), Departament d' Ecologia, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona - UB, Diagonal 643, 08028 Barcelona, Catalonia (Spain); Brucet, Sandra [Aquatic Ecology Group, BETA Tecnio Centre, University of Vic - Central University of Catalonia, Vic, Catalonia (Spain); Catalan Institution for Research and Advanced Studies, ICREA, Barcelona 08010 (Spain); Llenas, Laia; Ponsá, Sergio [Aquatic Ecology Group, BETA Tecnio Centre, University of Vic - Central University of Catalonia, Vic, Catalonia (Spain); Prat, Narcís [Grup de Recerca Freshwater Ecology and Management (FEM), Departament d' Ecologia, Facultat de Biologia, Universitat de Barcelona (UB), Diagonal 643, 08028 Barcelona, Catalonia (Spain); Soares, Amadeu M.V.M. [CESAM, Departamento de Biologia, Universidade de Aveiro, 3810-193 Aveiro (Portugal); and others

    2016-10-01

    The rivers and streams of the world are becoming saltier due to human activities. In spite of the potential damage that salt pollution can cause on freshwater ecosystems, this is an issue that is currently poorly managed. Here we explored intraspecific differences in the sensitivity of freshwater fauna to two major ions (Cl{sup −} and SO{sub 4}{sup 2−}) using the net-spinning caddisfly Hydropsyche exocellata Dufour 1841 (Trichoptera, Hydropsychidae) as a model organism. We exposed H. exocellata to saline solutions (reaching a conductivity of 2.5 mS cm{sup −1}) with Cl{sup −}:SO{sub 4}{sup 2−} ratios similar to those occurring in effluents coming from the meat, mining and paper industries, which release dissolved salts to rivers and streams in Spain. We used two different populations, coming from low and high conductivity streams. To assess toxicity, we measured sub-lethal endpoints: locomotion, symmetry of the food-capturing nets and oxidative stress biomarkers. According to biomarkers and net building, the population historically exposed to lower conductivities (B10) showed higher levels of stress than the population historically exposed to higher conductivities (L102). However, the differences between populations were not strong. For example, net symmetry was lower in the B10 than in the L102 only 48 h after treatment was applied, and biomarkers showed a variety of responses, with no discernable pattern. Also, treatment effects were rather weak, i.e. only some endpoints, and in most cases only in the B10 population, showed a significant response to treatment. The lack of consistent differences between populations and treatments could be related to the high salt tolerance of H. exocellata, since both populations were collected from streams with relatively high conductivities. The sub-lethal effects tested in this study can offer an interesting and promising tool to monitor freshwater salinization by combining physiological and behavioural bioindicators

  3. Sublethal effect of neem extract on mediterranean fruit fly adults

    Directory of Open Access Journals (Sweden)

    Márcio Alves Silva

    2013-03-01

    Full Text Available The sublethal effect of extracts of Azadirachta indica on Ceratitis capitata was evaluated. Two pairs of flies were treated in plastic tubes with cotton placed in plastic cages. An artificial diet (hydrolyzed protein + sugar was provided ad libitum. The extracts affected significantly the longevity of C. capitata. The pre-oviposition period were not significantly affected by the extracts. The A. indica branches extracted with dichloromethane (888 ppm affected significantly the fecundity and fertility, reducing the number of eggs laid to approximately 80 % and the egg hatching by 30 % at the 8th day. Therefore, the neem branches extracted with dichloromethane affected the reproduction of C. capitata.

  4. The role of sublethal effects in evaluating earthworm responses to soil contamination

    Energy Technology Data Exchange (ETDEWEB)

    Wilborn, D.; Bollman, M.; Linder, G. [ManTech Environmental Technology, Inc., Corvallis, OR (United States)

    1994-12-31

    Frequently, standard test methods rely upon relatively straightforward, easily interpreted endpoints to evaluate biological effects, like growth inhibition, gross morbidity or death. In soil contamination evaluations, for example, earthworm toxicity tests are routinely completed in order to consider adverse biological effects associated with exposures to soil samples in the laboratory or field. Here, the toxicity endpoint measured in the standard test using Eisenia foetida is death; however, if chronic effects are more appropriate to the questions being asked within a risk assessment context, then alternative test endpoints must be developed and standardized. Prior evaluations have relied upon sublethal endpoints, most frequently behavioral and morphological observations, for evaluating chronic effects associated with contaminant exposures. The authors applied these behavioral and morphological endpoints in analyzing potential chronic effects in earthworms exposed to heavy metal-contaminated soils in both the laboratory and field. In using a relatively standard set of these sublethal endpoints the authors found that these endpoints could be used to evaluate chronic effects associated with soil exposures, but that selection of the specific end-points had to be adequately standardized and that observer bias had to be adequately characterized in order for these measures of chronic effects to be unequivocally applied within an ecological risk assessment.

  5. Sublethal Dose of Diazinon Induces Pulmonary Toxicity in Rat: Histopathological Evidence

    Directory of Open Access Journals (Sweden)

    Gholamreza Najafi

    2014-02-01

    Full Text Available Objective: Diazinon (DZ is a widely used contact organophosphorous pesticide with broad spectrum insecticide activity. The extensive use of DZ has caused great concern due to the hazardous side effects on human beings as well as wild and domestic animals. The aim of this study was to investigate the effect of sublethal dose of DZ on rat lung. Material and methods: Seven groups of male Wistar rats were used comprising control and test groups. The control group received corn oil (0.3 ml/day for 60 days by oral gavages. The test groups received DZ at a dose of 60 mg/kg body weight orally for 2, 10, 24, 30, 54 and 60 days, respectively. Results: The histopathological analysis of the lungs in DZ-treated groups revealed congestion on day 2, pulmonary edema and emphysema on day 10, congestion and atelectasia on day 24, infiltration of mononuclear cells on day 30 and pulmonary hemorrhage along with bronchial glands hyperplasia on days 54 and 60. DZ administration also caused a significant decrease in serum cholinesterase activity in a time-dependent manner. Conclusion: These findings indicate that sublethal dose of DZ can induce severe lesions in the lung of rat. [J Interdiscipl Histopathol 2014; 2(1.000: 26-31

  6. Toxic effects of selenium and copper on the planarian, Dugesia dorotocephala

    Energy Technology Data Exchange (ETDEWEB)

    Rauscher, J.D.

    1988-01-01

    Aquatic toxicologists have become increasingly concerned with the effects of sublethal concentrations of toxicants on aquatic organisms. Sublethal effects of toxicants on freshwater invertebrates were reviewed. Selenium (Se) and copper (Cu) are both essential trace elements and toxicants. Se has been reported to alter the toxicity of heavy metals. Planarians, Dugesia dorotocephala, were used as test animals. The objectives of this study were to determine: (1) acute toxicity of Se on planarians and the effect of the number of planarians per test chamber, (2) interaction of the acute toxicity of Se and Cu on planarians, and (3) sublethal effects of Se and Cu on planarians.

  7. Development and application of a sublethal toxicity test to PAH using marine harpacticoid copepods. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fleeger, J.W.; Lotufo, G.R.

    1999-01-01

    This research project was designed to improve the understanding of the acute and sublethal effects of PAHs to benthic invertebrates. Sublethal bioassay protocols for benthic harpacticoid copepods were developed, and two species of harpacticoids were exposed to a range of concentrations of sediment-amended PAHs; the single compounds fluoranthene and phenanthrene as well as a complex mixture (diesel fuel). The harpacticoid copepods Schizopera knabeni and Nitocra lacustris were tested using several bioassay approaches. Reproductive assays, feeding assays and avoidance tests were conducted in addition to lethal tests for S. knabeni. Species-specific differences in sensitivity were detected. Early life history stages were much more sensitive than adults in one species but not in the other. Concentrations of PAH as low as 26 micrograms PAH decreased copepod offspring production, egg hatching success, and embryonic and early-stage development, demonstrating the high sensitivity of life history-related endpoints. In addition, grazing on microalgae was significantly impaired at concentrations as low as 20 micrograms/g PAH after short exposures (<30 h). Finally it was demonstrated that harpacticoids can actively avoid contamination.

  8. Effects of Sublethal Doses of Imidacloprid on Young Adult Honeybee Behaviour

    Science.gov (United States)

    Mengoni Goñalons, Carolina; Farina, Walter Marcelo

    2015-01-01

    Imidacloprid (IMI), a neonicotinoid used for its high selective toxicity to insects, is one of the most commonly used pesticides. However, its effect on beneficial insects such as the honeybee Apis mellifera L is still controversial. As young adult workers perform in-hive duties that are crucial for colony maintenance and survival, we aimed to assess the effect of sublethal IMI doses on honeybee behaviour during this period. Also, because this insecticide acts as a cholinergic-nicotinic agonist and these pathways take part in insect learning and memory processes; we used IMI to assess their role and the changes they suffer along early adulthood. We focused on appetitive behaviours based on the proboscis extension response. Laboratory reared adults of 2 to 10 days of age were exposed to sublethal IMI doses (0.25 or 0.50ng) administered orally or topically prior to behavioural assessment. Modification of gustatory responsiveness and impairment of learning and memory were found as a result of IMI exposure. These outcomes differed depending on age of evaluation, type of exposure and IMI dose, being the youngest bees more sensitive and the highest oral dose more toxic. Altogether, these results imply that IMI administered at levels found in agroecosystems can reduce sensitivity to reward and impair associative learning in young honeybees. Therefore, once a nectar inflow with IMI traces is distributed within the hive, it could impair in-door duties with negative consequences on colony performance. PMID:26488410

  9. Sublethal effects of manganese on the carbohydrate metabolism of ...

    African Journals Online (AJOL)

    Carbohydrate metabolism variables of Oreochromis mossambicuswere investigated after acute and chronic sublethal manganese exposure. The sublethal concentrations were determined from the LC50 value of manganese. After the exposures, the fish were carefully netted and blood was drawn from the caudal aorta.

  10. Sublethal effects of waterborne herbicides in tropical freshwater fish.

    Science.gov (United States)

    Rossi, Stéfani Cibele; Dreyer da Silva, Manuela; Piancini, Laercio Dante Stein; Oliveira Ribeiro, Ciro Alberto; Cestari, Marta Margarete; Silva de Assis, Helena Cristina

    2011-12-01

    The study evaluated the sublethal effects of the herbicides glyphosate (Roundup) and diuron (Hexaron) and the mixture of them, used extremely in agriculture, through biomarkers in fish. The glutathione S-transferase activity increased (74%) and catalase activity decreased (37%) at the higher exposure concentration of Hexaron in comparison to the control group, suggesting an activation of this metabolism route. Membrane damage was observed at the higher exposure of Roundup and in the mixture group compared to the control group, which can be related to the nuclear alterations observed in these exposed groups. The cholinesterase activity was also inhibited (37%) in mixture group compared to the control group and no gill morphology damage was found. The results suggested a potential synergic effect in some analysed parameters.

  11. Assessment of the lethal and sublethal effects of 20 environmental chemicals in zebrafish embryos and larvae by using OECD TG 212.

    Science.gov (United States)

    Horie, Yoshifumi; Yamagishi, Takahiro; Takahashi, Hiroko; Shintaku, Youko; Iguchi, Taisen; Tatarazako, Norihisa

    2017-10-01

    Fish embryo toxicity tests are used to assess the lethal and sublethal effects of environmental chemicals in aquatic organisms. Previously, we used a short-term toxicity test published by the Organization for Economic Co-operation and Development (test no. 212: Fish, Short-term Toxicity Test on Embryo and Sac-Fry Stages [OECD TG 212]) to assess the lethal and sublethal effects of aniline and several chlorinated anilines in zebrafish embryos and larvae. To expand upon this previous study, we used OECD TG 212 in zebrafish embryos and larvae to assess the lethal and sublethal effects of 20 additional environmental chemicals that included active pharmaceutical ingredients, pesticides, metals, aromatic compounds or chlorinated anilines. Zebrafish embryos (Danio rerio) were exposed to the test chemicals until 8 days post-fertilization. A delayed lethal effect was induced by 16 of the 20 test chemicals, and a positive correlation was found between heart rate turbulence and mortality. We also found that exposure to the test chemicals at concentrations lower than the lethal concentration induced the sublethal effects of edema, body curvature and absence of swim-bladder inflation. In conclusion, the environmental chemicals assessed in the present study induced both lethal and sublethal effects in zebrafish embryos and larvae, as assessed by using OECD TG 212. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Sublethal effects of cadmium, manganese, lead, zinc and iron on the ...

    African Journals Online (AJOL)

    This study also evaluated the sublethal effects of cadmium, manganese, lead, zinc and iron in plasma samples utilising plasma electrolyte parameters as a biomarker using an albino mice model, M. musculus. Mice were subjected to sublethal concentrations of the selected heavy metals (1/10th of 96 hrLC50). Blood plasma ...

  13. Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

    Energy Technology Data Exchange (ETDEWEB)

    McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Alaee, Mehran [Environment Canada, 867 Lakeshore Rd., P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Simpson, Andre J. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada); Simpson, Myrna J., E-mail: myrna.simpson@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, ON M1C 1A4 (Canada)

    2011-12-15

    Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms. - Highlights: > NMR-based earthworm metabolomic analysis of the toxic mode of action of various environmental contaminants. > Organic chemicals with different toxic modes of action resulted in varied metabolomic responses for E. fetida. > NMR-based metabolomics differentiates between the different modes of action associated with sub-lethal toxicity. - {sup 1}H NMR metabolomics was used to identify potential biomarkers of organic contaminant exposure in Eisenia fetida earthworms.

  14. Glyphosate sub-lethal toxicity to non-target organisms occurring in Jatropha curcas plantations in Brazil.

    Science.gov (United States)

    de Saraiva, Althiéris Souza; Sarmento, Renato Almeida; Pedro-Neto, Marçal; Teodoro, Adenir Vieira; Erasmo, Eduardo Andrea Lemus; Belchior, Diana Cléssia Vieira; de Azevedo, Emiliano Brandão

    2016-10-01

    Weed management in physic nut plantations has generally been performed by spraying the herbicide glyphosate. However, the effects of glyphosate on non-target organisms present in the crop system are unknown. Here, we evaluated the toxicity of glyphosate (Roundup Transorb(®)) against the pest species Polyphagotarsonemus latus (Acari: Tarsonemidae) and Tetranychus bastosi (Acari: Tetranychidae) which can be exposed by drift. These mites are considered pests of the physic nut; however, they can also feed and reside on weeds associated with the crop, serving as food sources for predatory mites. When subjected to residue (by ingestion of sap of treated plants), and direct contact to glyphosate, P. latus reproduction was affected but T. bastosi was affected only by the residual effect. Although the herbicide caused a reduction in the number of eggs laid by the females of both pest mites, it is suggested that sublethal effects of glyphosate stimulates oviposition of P. latus and T. bastosi: both species displayed higher reproductive rates when exposed to 0.36 kg ha(-1) of the herbicide. We conclude that glyphosate negatively affects the arthropod herbivores studied and we discuss possible implications on their biological control in Jatropha curcas plantations.

  15. Sublethal and hormesis effects of imidacloprid on the soybean aphid Aphis glycines.

    Science.gov (United States)

    Qu, Yanyan; Xiao, Da; Li, Jinyu; Chen, Zhou; Biondi, Antonio; Desneux, Nicolas; Gao, Xiwu; Song, Dunlun

    2015-04-01

    The soybean aphid, Aphis glycines Matsumura, is a major pest in soybean crop. Current management of this pest relies mainly on insecticides applications, and the neonicotinoid imidacloprid has been proposed as an effective insecticide to control A. glycines in soybean field. Imidacloprid at lethal concentrations not only exerts acute toxicity to A. glycines, but also cause various biological changes when aphids are chronically exposed to lower concentrations. In this study, we assessed the effects of a low-lethal (0.20 mg L(-1)) and two sublethal (0.05 and 0.10 mg L(-1)) imidacloprid concentrations on various A. glycines life history traits. Aphid exposure to 0.20 mg L(-1) imidacloprid caused slower juvenile development, shorter reproductive period, and reduced adult longevity, fecundity and total lifespan. Stimulatory effects, i.e. hormesis, on reproduction and immature development duration were observed in aphids exposed to the lower sublethal imidacloprid concentrations. Consequently, the net reproduction rate (R 0) was significantly higher than in the control aphids. These findings stress the importance of the actual imidacloprid concentration in its toxicological properties on A. glycines. Therefore, our results would be useful for assessing the overall effects of imidacloprid on A. glycines and for optimizing integrated pest management programs targeting this pest.

  16. Effects of Sublethal Concentrations of Insecticides on the Functional Response of Two Mirid Generalist Predators.

    Directory of Open Access Journals (Sweden)

    Angeliki F Martinou

    Full Text Available The use of agrochemicals particularly pesticides, can hamper the effectiveness of natural enemies, causing disruption in the ecosystem service of biological control. In the current study, the effects of the insecticides thiacloprid and chlorantraniliprole on the functional response curves were assessed for two mirid predator nymphs, Macrolophus pygmaeus Rambur and Nesidiocoris tenuis Reuter. In the absence of insecticides, both predators exhibited a type II functional response when feeding on eggs of the moth Ephestia kuehniella. N. tenuis seems to be a more efficient predator than M. pygmaeus, as model estimated handling time was significantly lower for the former than for the latter. Residual exposure of M. pygmaeus to sublethal concentrations of either insecticide was associated with a change in the asymptote but not the type of the functional response curve. Thiacloprid seems to be the least compatible with M. pygmaeus, as it led to both a significant reduction of the attack rate and an increase in handling time. In contrast, chlorantraniliprole exposure significantly increased the handling time, but not the attack rate of the predator. Residual exposure of N. tenuis to sublethal concentrations of either insecticide did not have a significant effect on the type nor the parameters of the functional response model. The results show that pesticide residues that do not have lethal effects on beneficial arthropods can reduce prey consumption depending on predator species and on likely risks associated with toxicity.

  17. Lethal and sublethal effects of cyantraniliprole on Bactrocera dorsalis (Hendel) (Diptera: Tephritidae).

    Science.gov (United States)

    Zhang, Ruimin; Jang, Eric B; He, Shiyu; Chen, Jiahua

    2015-02-01

    The oriental fruit fly, Bactrocera dorsalis (Hendel), is one of the most globally important insect pests. Studies were conducted with the novel anthranilic diamide insecticide cyantraniliprole to determine its lethal and sublethal effects on B. dorsalis. An ingestion toxicity bioassay showed that cyantraniliprole was active against B. dorsalis, and the 72 h feeding LC50 was 3.22 µg g(-1) in adult diet for a susceptible strain. Sublethal doses of cyantraniliprole (1.30 µg g(-1) adult diet) induced a hormesis effect on B. dorsalis. The mating competitiveness of B. dorsalis treated with cyantraniliprole at 3.27 µg g(-1) adult diet was significantly lower when compared with the controls. The lower dose (1.30 µg g(-1) adult diet) of cyantraniliprole improved the total mating times of both mating pairs in treated groups and also the mating competitiveness of the treated males when compared with the higher dose and controls. Cyantraniliprole-treated females of the mated pairs with the lower dose laid more eggs. On the fifth day, female receptivity in the treated group was significantly reduced when compared with the controls. These results indicate that cyantraniliprole is effective against B. dorsalis. The inhibition and stimulation effect of cyantraniliprole on the adult's mating performance at different concentrations was proved. © 2014 Society of Chemical Industry.

  18. Lethal and sublethal effects of four essential oils on the egg parasitoids Trissolcus basalis.

    Science.gov (United States)

    Werdin González, Jorge Omar; Laumann, Raúl Alberto; da Silveira, Samantha; Moraes, Maria Carolina Blassioli; Borges, Miguel; Ferrero, Adriana Alicia

    2013-07-01

    The essential oils from leaves of Schinus molle var. areira, Aloysia citriodora, Origanum vulgare and Thymus vulgaris have showed potential as phytoinsecticides against the green stink bug, Nezara viridula. In this work were evaluated their toxicological and behavioral effects on the parasitoid Trissolcus basalis, a biological control agent of this pest insect. Essential oils were obtained via hydrodestillation from fresh leaves. Insecticide activity in T. basalis females was evaluated in direct contact and fumigation bioassays. Behavioral effects were evaluated in olfactometer bioassays. To evaluate the residual toxicity, females of the parasitoids were exposed to oil residues; in these insects, the sublethal effects were evaluated (potential parasitism and survivorship of immature stages). The essential oils from O. vulgare and T. vulgaris proved to be highly selective when used as fumigant and did not change parasitoid behavior. After one week, the residues of these oils were harmless and did not show sublethal effects against T. basalis. According with these results, essential oils have potential applications for the integrated management of N. viridula. Published by Elsevier Ltd.

  19. Do biopesticides affect the demographic traits of a parasitoid wasp and its biocontrol services through sublethal effects?

    Directory of Open Access Journals (Sweden)

    Antonio Biondi

    Full Text Available Pesticide risk assessments are usually based on short-term acute toxicity tests, while longer-term population dynamic related traits, critical to the success of biological control and Integrated Pest Management (IPM programs, are often overlooked. This is increasingly important with respect to new biopesticides that frequently cause no short-term acute effects, but that can induce multiple physiological and behavioral sublethal effects, leading to a decrease in population growth and ecosystem services. In this study we assessed the lethal and sublethal effects of six biopesticides [abamectin, azadirachtin, Bacillus thuringiensis, borax plus citrus oil (Prev-Am®, emamectin benzoate, and spinosad], used in tomato crops to control the invasive pest Tuta absoluta (Lepidoptera: Gelechiidae, on adults and pupae of the parasitoid Bracon nigricans (Hymenoptera: Braconidae. Data on female survival and production of female offspring were used to calculate population growth indexes as a measure of population recovery after pesticide exposure. Spinosad caused 100% and 80% mortality in exposed adults (even 10 d after the treatment and pupae, respectively. Although most of the biopesticides had low levels of acute toxicity, multiple sublethal effects were observed. The biocontrol activity of both females that survived 1-h and 10-d old residues, and females that emerged from topically treated pupae was significantly affected by the application of the neurotoxic insecticides emamectin benzoate and abamectin. Furthermore, very low B. nigricans demographic growth indices were estimated for these two insecticides, indicating potential local extinction of the wasp populations. Among the tested products, Bt proved to be the safest for B. nigricans adults and pupae. Our findings emphasize that acute toxicity assessment alone cannot fully predict the actual impact of pesticides on non-target parasitoids. Thus, sublethal effects related to the species specific life

  20. Do Biopesticides Affect the Demographic Traits of a Parasitoid Wasp and Its Biocontrol Services through Sublethal Effects?

    Science.gov (United States)

    Biondi, Antonio; Zappalà, Lucia; Stark, John D.; Desneux, Nicolas

    2013-01-01

    Pesticide risk assessments are usually based on short-term acute toxicity tests, while longer-term population dynamic related traits, critical to the success of biological control and Integrated Pest Management (IPM) programs, are often overlooked. This is increasingly important with respect to new biopesticides that frequently cause no short-term acute effects, but that can induce multiple physiological and behavioral sublethal effects, leading to a decrease in population growth and ecosystem services. In this study we assessed the lethal and sublethal effects of six biopesticides [abamectin, azadirachtin, Bacillus thuringiensis, borax plus citrus oil (Prev-Am®), emamectin benzoate, and spinosad], used in tomato crops to control the invasive pest Tuta absoluta (Lepidoptera: Gelechiidae), on adults and pupae of the parasitoid Bracon nigricans (Hymenoptera: Braconidae). Data on female survival and production of female offspring were used to calculate population growth indexes as a measure of population recovery after pesticide exposure. Spinosad caused 100% and 80% mortality in exposed adults (even 10 d after the treatment) and pupae, respectively. Although most of the biopesticides had low levels of acute toxicity, multiple sublethal effects were observed. The biocontrol activity of both females that survived 1-h and 10-d old residues, and females that emerged from topically treated pupae was significantly affected by the application of the neurotoxic insecticides emamectin benzoate and abamectin. Furthermore, very low B. nigricans demographic growth indices were estimated for these two insecticides, indicating potential local extinction of the wasp populations. Among the tested products, Bt proved to be the safest for B. nigricans adults and pupae. Our findings emphasize that acute toxicity assessment alone cannot fully predict the actual impact of pesticides on non-target parasitoids. Thus, sublethal effects related to the species specific life-history variables

  1. Low salinity enhances NI-mediated oxidative stress and sub-lethal toxicity to the green shore crab (Carcinus maenas).

    Science.gov (United States)

    Blewett, Tamzin A; Wood, Chris M

    2015-12-01

    Nickel (Ni) is a metal of environmental concern, known to cause toxicity to freshwater organisms by impairing ionoregulation and/or respiratory gas exchange, and by inducing oxidative stress. However, little is known regarding how nickel toxicity is influenced by salinity. In the current study we investigated the salinity-dependence and mechanisms of sub-lethal Ni toxicity in a euryhaline crab (Carcinus maenas). Crabs were acclimated to three experimental salinities--20, 60 and 100% seawater (SW)--and exposed to 3mg/L Ni for 24h or 96 h. Tissues were dissected for analysis of Ni accumulation, gills were taken for oxidative stress analysis (catalase activity and protein carbonyl content), haemolymph ions were analysed for ionoregulatory disturbance, and oxygen consumption was determined in exercised crabs after 96 h of Ni exposure. Total Ni accumulation was strongly dependant on salinity, with crabs from 20% SW displaying the highest tissue Ni burdens after both 24 and 96-h exposures. After 96 h of exposure, the highest accumulation of Ni occurred in the posterior (ionoregulatory) gills at the lowest salinity, 20% SW. Posterior gill 8 exhibited elevated protein carbonyl levels and decreased catalase activity after Ni exposure, but only in 20% SW. Similarly, decreased levels of haemolymph Mg and K and an increased level of Ca were recorded but only in crabs exposed to Ni for 96 h in 20% SW. Oxygen consumption after exercise was also inhibited in crabs exposed to Ni in 20% SW. These data show for the first time the simultaneous presence of all three modes of sub-lethal Ni toxicity in exposed animals, and indicate a strong salinity dependence of sub-lethal Ni toxicity to the euryhaline crab, C. maenas, a pattern that corresponded to tissue Ni accumulation. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Using photopigment biomarkers to quantify sub-lethal effects of petroleum pollution on natural phytoplankton assemblages

    Energy Technology Data Exchange (ETDEWEB)

    Swistak, J.; Pinckney, J.; Piehler, M.; Paerl, H. [Univ. of North Carolina, Morehead City, NC (United States). Inst. of Marine Sciences

    1995-12-31

    Although much work has been undertaken to determine the toxicity of petroleum pollutants to phytoplankton, most studies have used pure cultures to monitor growth of selected phytoplankton species. Fewer have considered the net effect on entire microalgal communities. Using high performance liquid chromatography (HPLC) to characterize diagnostic microalgal pigments, the authors were able to simultaneously assess sub-lethal pollutant effects on entire communities as well as on individual phytoplankton functional groups. Incubations of natural water samples with diesel fuel, an important contributor to coastal petroleum pollution, revealed significant changes in photopigments and relative abundance of taxonomic groups at sub-lethal concentrations. Differential rates of change of indicator pigment concentrations suggest a range of sensitivity among phytoplankton groups. In preliminary experiments, cyanobacteria exhibited the greatest overall tolerance to the diesel fuel concentrations tested, while cryptomonads displayed the most sensitivity. The authors are currently evaluating the responses of seasonal phytoplankton populations from 3 sites exposed to varied levels of petroleum pollution. HPLC will be used to characterize phytoplankton populations and to determine if the most abundant groups are also the most tolerant of diesel fuel. Preliminary experiments indicate that diesel fuel pollution may modify the structure and function of phytoplankton communities and subsequently alter the trophodynamics of impacted systems.

  3. Sublethal Effects in Pest Management: A Surrogate Species Perspective on Fruit Fly Control

    Directory of Open Access Journals (Sweden)

    John E. Banks

    2017-07-01

    Full Text Available Tephritid fruit flies are economically important orchard pests globally. While much effort has focused on controlling individual species with a combination of pesticides and biological control, less attention has been paid to managing assemblages of species. Although several tephritid species may co-occur in orchards/cultivated areas, especially in mixed-cropping schemes, their responses to pesticides may be highly variable. Furthermore, predictive efforts about toxicant effects are generally based on acute toxicity, with little or no regard to long-term population effects. Using a simple matrix model parameterized with life history data, we quantified the responses of several tephritid species to the sublethal effects of a toxicant acting on fecundity. Using a critical threshold to determine levels of fecundity reduction below which species are driven to local extinction, we determined that threshold levels vary widely for the three tephritid species. In particular, Bactrocera dorsalis was the most robust of the three species, followed by Ceratitis capitata, and then B. cucurbitae, suggesting individual species responses should be taken into account when planning for area-wide pest control. The rank-order of susceptibility contrasts with results from several field/lab studies testing the same species, suggesting that considering a combination of life history traits and individual species susceptibility is necessary for understanding population responses of species assemblages to toxicant exposure.

  4. Sublethal Toxic Effects and Induction of gGutathione S-transferase by Short-Chain Chlorinated Paraffins (SCCPs and C-12 alkane (dodecane in Xenopus laevis Frog Embryos

    Directory of Open Access Journals (Sweden)

    B. Burýšková

    2006-01-01

    Full Text Available Short chain chlorinated paraffins (SCCPs are important industrial chemicals with high persistence in the environment but poorly characterized ecotoxicological effects. We studied embryotoxic effects of commercial mixture of SCCP (carbon length C-12, 56% of chlorine; CP56-12 and non-chlorinated n-alkane (dodecane, C-12 in the 96h Frog Embryo Teratogenesis Assay - Xenopus (FETAX. Only weak lethal effects were observed for both substances (the highest tested concentration 500 mg/L of both chemicals caused up to 11% mortality. On the other hand, we observed developmental malformations and reduced embryo growth at 5 mg/l and higher concentrations. However, the effects were not related to chlorination pattern as both SCCPs and dodecane induced qualitatively similar effects. SCCPs also significantly induced phase II detoxification enzyme glutathione S-transferase (GST in Xenopus laevis embryos even at 0.5 mg/L, and this biomarker might be used as another early warning of chronic toxic effects. Our results newly indicate significant developmental toxicity of both SCCPs and n-dodecane to aquatic organisms along with inductions of specific biochemical toxicity mechanisms.

  5. Effects of Sublethal Doses of Imidacloprid on Young Adult Honeybee Behaviour: e0140814

    National Research Council Canada - National Science Library

    Gonalons, Carolina Mengoni; Farina, Walter Marcelo

    2015-01-01

    .... As young adult workers perform in-hive duties that are crucial for colony maintenance and survival, we aimed to assess the effect of sublethal IMI doses on honeybee behaviour during this period...

  6. Effects of Sublethal Doses of Imidacloprid on Young Adult Honeybee Behaviour

    National Research Council Canada - National Science Library

    Mengoni Goñalons, Carolina; Farina, Walter Marcelo

    2015-01-01

    .... As young adult workers perform in-hive duties that are crucial for colony maintenance and survival, we aimed to assess the effect of sublethal IMI doses on honeybee behaviour during this period...

  7. Metalloporphyrin Co(III)TMPyP ameliorates acute, sublethal cyanide toxicity in mice.

    Science.gov (United States)

    Benz, Oscar S; Yuan, Quan; Amoscato, Andrew A; Pearce, Linda L; Peterson, Jim

    2012-12-17

    The formation of Co(III)TMPyP(CN)(2) at pH 7.4 has been shown to be completely cooperative (α(H) = 2) with an association constant of 2.1 (±0.2) × 10(11). The kinetics were investigated by stopped-flow spectrophotometry and revealed a complicated net reaction exhibiting 4 phases at pH 7.4 under conditions where cyanide was in excess. The data suggest molecular HCN (rather than CN(-)) to be the attacking nucleophile around neutrality. The two slower phases do not seem to be present when cyanide is not in excess, and the other two phases have rates comparable to that observed for cobalamin, a known effective cyanide scavenger. Addition of bovine serum albumin (BSA) did not affect the cooperativity of cyanide binding to Co(III)TMPyP, only lowered the equilibrium constant slightly to 1.2 (±0.2) × 10(11) and had an insignificant effect on the observed rate. A sublethal mouse model was used to assess the effectiveness of Co(III)TMPyP as a potential cyanide antidote. The administration of Co(III)TMPyP to sodium cyanide intoxicated mice resulted in the time required for the surviving mice to right themselves from a supine position being significantly decreased (9 ± 2 min) compared to that of the controls (33 ± 2 min). All observations were consistent with the demonstrated antidotal activity of Co(III)TMPyP operating through a cyanide-binding (i.e., scavenging) mechanism.

  8. Sublethal effects of industrial chemicals on fish fingerlings ( Tilapia ...

    African Journals Online (AJOL)

    Tilapia guineensis commonly found in the Niger Delta ecological zone of Nigeria was exposed to sublethal concentrations (1.56, 3.13 mg/l) of neatex (industrial detergent) and norust CR 486 (corrosion inhibitor) using the Organisation for Economic Cooperation and Development (OECD) # 203 protocol. At test termination ...

  9. Effects Of Exposure To Sublethal Concentrations Of Azadirachta ...

    African Journals Online (AJOL)

    The physiological impairment on the fingerlings of Clarias gariepinus when exposed to sublethal concentrations of Azadirachta Indica was investigated. The fish were exposed to concentrations of 1.25, 2.50, 5.0, 10.0, 20.0 ML -1 for the period of 12 weeks. The crude protein content decreased with increased concentration ...

  10. Lethal and Sub-lethal Effects of Four Insecticides on the Aphidophagous Coccinellid Adalia bipunctata (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Depalo, Laura; Lanzoni, Alberto; Masetti, Antonio; Pasqualini, Edison; Burgio, Giovanni

    2017-12-05

    Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. An analysis of lethal and sublethal interactions among type I and type II pyrethroid pesticide mixtures using standard Hyalella azteca water column toxicity tests.

    Science.gov (United States)

    Hoffmann, Krista Callinan; Deanovic, Linda; Werner, Inge; Stillway, Marie; Fong, Stephanie; Teh, Swee

    2016-10-01

    A novel 2-tiered analytical approach was used to characterize and quantify interactions between type I and type II pyrethroids in Hyalella azteca using standardized water column toxicity tests. Bifenthrin, permethrin, cyfluthrin, and lambda-cyhalothrin were tested in all possible binary combinations across 6 experiments. All mixtures were analyzed for 4-d lethality, and 2 of the 6 mixtures (permethrin-bifenthrin and permethrin-cyfluthrin) were tested for subchronic 10-d lethality and sublethal effects on swimming motility and growth. Mixtures were initially analyzed for interactions using regression analyses, and subsequently compared with the additive models of concentration addition and independent action to further characterize mixture responses. Negative interactions (antagonistic) were significant in 2 of the 6 mixtures tested, including cyfluthrin-bifenthrin and cyfluthrin-permethrin, but only on the acute 4-d lethality endpoint. In both cases mixture responses fell between the additive models of concentration addition and independent action. All other mixtures were additive across 4-d lethality, and bifenthrin-permethrin and cyfluthrin-permethrin were also additive in terms of subchronic 10-d lethality and sublethal responses. Environ Toxicol Chem 2016;35:2542-2549. © 2016 SETAC. © 2016 SETAC.

  12. Sub-lethal effects of herbicides penoxsulam, imazamox, fluridone and glyphosate on Delta Smelt (Hypomesus transpacificus).

    Science.gov (United States)

    Jin, Jiali; Kurobe, Tomofumi; Ramírez-Duarte, Wilson F; Bolotaolo, Melissa B; Lam, Chelsea H; Pandey, Pramod K; Hung, Tien-Chieh; Stillway, Marie E; Zweig, Leanna; Caudill, Jeffrey; Lin, Li; Teh, Swee J

    2018-02-01

    Concerns regarding non-target toxicity of new herbicides used to control invasive aquatic weeds in the San Francisco Estuary led us to compare sub-lethal toxicity of four herbicides (penoxsulam, imazamox, fluridone, and glyphosate) on an endangered fish species Delta Smelt (Hypomesus transpacificus). We measured 17β-estradiol (E2) and glutathione (GSH) concentrations in liver, and acetylcholinesterase (AChE) activity in brain of female and male fish after 6 h of exposure to each of the four herbicides. Our results indicate that fluridone and glyphosate disrupted the E2 concentration and decreased glutathione concentration in liver, whereas penoxsulam, imazamox, and fluridone inhibited brain AChE activity. E2 concentrations were significantly increased in female and male fish exposed to 0.21 μM of fluridone and in male fish exposed to 0.46, 4.2, and 5300 μM of glyphosate. GSH concentrations decreased in males exposed to fluridone at 2.8 μM and higher, and glyphosate at 4.2 μM. AChE activity was significantly inhibited in both sexes exposed to penoxsulam, imazamox, and fluridone, and more pronounced inhibition was observed in females. The present study demonstrates the potential detrimental effects of these commonly used herbicides on Delta Smelt. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Sublethal effects of atrazine on embryo-larval development of Rhinella arenarum (Anura: Bufonidae).

    Science.gov (United States)

    Svartz, Gabriela V; Herkovits, Jorge; Pérez-Coll, Cristina S

    2012-05-01

    Atrazine (ATR), one of the most widely used herbicides in the world, affects not only target organisms but also the biota in general. Here, the teratogenic and neurotoxic effects of ATR on Rhinella arenarum (South American toad) embryos, and larvae were evaluated by means of standardized bioassays during acute and chronic exposures. The herbicide had a significant incidence of malformations, with a Teratogenic Index (TI) of 3.28. The main effects were delayed development, reduced body size, microcephaly, axial flexures, wavy tail and edema. In addition, delayed development, reduced development of forelimbs, and edema were recorded at metamorphosis stages. Scanning electron microscopy allowed observing different degrees of cellular dissociation and persistent cilliar cells in specific regions like the adhesive structure and tail fin. Results obtained by ATR 24 h pulse exposures at six developmental stages pointed out blastula as the most susceptible developmental stage both for immediate and delayed adverse effects. A noteworthy recovery capacity from acute toxic effects was recorded from the neural plate stage onwards. Regarding neurotoxic effects, abnormal, and erratic swimming and spasmodic contractions were recorded. Both the teratogenic and neurotoxic effects reported in this study demonstrate the importance of evaluating sublethal effects in non-target organisms as they could imply reduced fitness of individuals and eventually a population decline. The Hazard Quotients (HQ) for ATR ranged from 0.14 to 10.80, and the fact that some of these values are above USEPA's level of concern indicate that ATR is likely a risk to R. arenarum.

  14. Sub-lethal toxicity of chlorpyrifos on Common carp, Cyprinus carpio (Linnaeus, 1758: Biochemical response

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-01-01

    Full Text Available Chlorpyrifos, an organophosphate pesticide, is widely used to control pests in agriculture farms and orchards of fruit trees. In this study, the fish were exposed to sub-lethal concentrations of chlorpyrifos which were determined based on numerical value of 96 h LC50. Blood was sampled after 10, 20 and 30 days and biochemical parameters including glucose, total protein, albumin, globulin, triglyceride and cholesterol levels, and aspartate aminotransferase (AST, alanine aminotransferase (ALT, lactate dehydrogenase (LDH, creatine kinase (CK, alkaline phosphatase (ALP and acetylcholinsetrase (AChE activities were measured. Behavioral changes in the fish were also recorded during the experiment. Unbalanced swimming, swimming in the surface water and hyperglycemia, increased blood triglyceride, and increased levels of AST, LDH and CK activities as well as decreased levels of AChE activity were important changes that were observed in the specimens exposed to chlorpyrifos during experimental periods. The most important alterations in the blood biochemical parameters were measured in the specimens exposed to 40 µg/L chlorpyrifos on the 20th and 30th day of the trial. In conclusion, results of the present study indicated that exposure to sub-lethal concentrations of chlorpyrifos as low as 40 µg/L may cause biochemical and behavioral changes in Cyprinus carpio.

  15. Sublethal effects of some synthetic and botanical insecticides on Bemisia tabaci (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Esmaeily Saeideh

    2014-07-01

    Full Text Available In addition to direct mortality caused by insecticides, some biological traits of insects may also be affected by sublethal insecticide doses. In this study, we used the age-stage, two-sex life table method to evaluate the sublethal effects of the four synthetic insecticides: abamectin, imidacloprid, diazinon, and pymetrozin as well as the botanical insecticide taken from Calotropis procera (Asclepiadaceae extract, on eggs of the cotton whitefly, Bemisia tabaci (Hem.: Aleyrodidae. The lowest and highest survival rates and oviposition periods were observed in whiteflies treated by diazinon and imidacloprid, respectively. We found significant differences in the net reproductive rate (R0, the intrinsic rate of increase (r, the finite rate of increase (?, and the gross reproductive rate (GRR among different insecticides. Altogether, our results showed that pymetrozin and C. procera induced the most sublethal effects, thus they may be suitable candidates for use in integrated pest management programs of B. tabaci.

  16. Sublethal toxicity of quinalphos on oxidative stress and antioxidant responses in a freshwater fish Cyprinus carpio.

    Science.gov (United States)

    Hemalatha, Devan; Amala, Antony; Rangasamy, Basuvannan; Nataraj, Bojan; Ramesh, Mathan

    2016-11-01

    Extensive use of quinalphos, an organophosphorus pesticide, is likely to reach the aquatic environment and thereby posing a health concern for aquatic organisms. Oxidative stress and antioxidant responses may be good indicators of pesticide contamination in aquatic organisms. The data on quinalphos induced oxidative stress and antioxidant responses in carps are scanty. This study is aimed to assess the two sublethal concentrations of quinalphos (1.09 and 2.18 μL L -1 ) on oxidative stress and antioxidant responses of Cyprinus carpio for a period of 20 days. In liver, the malondialdehyde level was found to be significantly increased in both the concentrations. The results of the antioxidant parameters obtained show a significant increase in superoxide dismutase, catalase, and glutathione-S-transferase activity in liver of fish. These results demonstrate that environmentally relevant levels of the insecticide quinalphos can cause oxidative damage and increase the antioxidant scavenging capacity in C. carpio. This may reflect the potential role of these parameters as useful biomarkers for the assessment of pesticide contamination. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1399-1406, 2016. © 2015 Wiley Periodicals, Inc.

  17. Assessment of chronic sublethal effects of imidacloprid on honey bee colony health

    Science.gov (United States)

    Here we present results of a three-year study to determine the fate of imidacloprid residues in hive matrices and to assess chronic sublethal effects on whole honey bee colonies fed supplemental pollen diet containing imidacloprid at 5, 20 and 100 µg/kg over multiple brood cycles. Various endpoints ...

  18. Effect of sublethal preculturing on the survival of probiotics and metabolite formation in set-yoghurt

    NARCIS (Netherlands)

    Settachaimongkon, S.; Valenberg, van H.J.F.; Winata, V.; Wang, X.; Nout, M.J.R.; Hooijdonk, van A.C.M.; Zwietering, M.H.; Smid, E.J.

    2015-01-01

    The objective of this study was to investigate the effect of preculturing of Lactobacillus rhamnosus GG and Bifidobacterium animalis subsp. lactis BB12 under sublethal stress conditions on their survival and metabolite formation in set-yoghurt. Prior to co-cultivation with yoghurt starters in milk,

  19. Sub-lethal effects of neonicitinoids on the alfalfa leafcutter bee, Megachile rotundata

    Science.gov (United States)

    Neonicotinoids are commonly used pesticides in U.S. agriculture. For many beneficial insect species, lethal effects of neonicotinoids are well-documented; however, much less is known about sublethal exposure. The alfalfa leaf cutter bee Megachile rotundata is a managed pollinator that constructs com...

  20. Monitoring colony-level effects of sublethal pesticide exposure on honey bees

    Science.gov (United States)

    The effects of sublethal pesticide exposure to honey bee colonies may be significant but difficult to detect in the field using standard visual assessment methods. Here we describe methods to measure the quantities of adult bees, brood and food resources by weighing hives and hive parts, by photogra...

  1. Effects of sub-lethal concentrations of a vegetable oil mill effluent on ...

    African Journals Online (AJOL)

    Effects of sub-lethal concentrations of a vegetable oil mill effluent on growth of Clarius gariepinus. JA Adakole, E Alabi. Abstract. No Abstract. Nigerian Journal of Fisheries Vol. 4 (2) 2007: pp. 182-189. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  2. Effects of IL-10 on systemic inflammatory responses during sublethal primate endotoxemia

    NARCIS (Netherlands)

    van der Poll, T.; Jansen, P. M.; Montegut, W. J.; Braxton, C. C.; Calvano, S. E.; Stackpole, S. A.; Smith, S. R.; Swanson, S. W.; Hack, C. E.; Lowry, S. F.; Moldawer, L. L.

    1997-01-01

    IL-10 protects mice from LPS-induced lethality. To determine the effects of IL-10 on LPS-induced inflammatory responses, six Papio anubis baboons were i.v. injected with a sublethal dose of LPS (Salmonella typhimurium; 500 microg/kg) directly preceded by either human rIL-10 (n = 3, 500 microg/kg) or

  3. Quantifying sublethal effects of glyphosate and Roundup® to Daphnia magna using a fluorescence based enzyme activity assay and video tracking

    DEFF Research Database (Denmark)

    Roslev, Peter; R. Hansen, Lone; Ørsted, Michael

    Glyphosate (N-(phosphonomethyl)glycine) is the active ingredient in a range of popular broad-spectrum, non-selective herbicide formulations. The toxicity of this herbicide to non-target aquatic organisms such as Daphnia magna is often evaluated using conventional toxicity assays that focus...... on endpoints such as immobility and mortality. In this study, we investigated sublethal effects of glyphosate and Roundup® to D. magna using video tracking for quantifying behavioral changes, and a novel fluorescence based assay for measuring in vivo hydrolytic enzyme activity (FLEA assay). Roundup® exposure...... resulted in concentration-dependent inhibition of alkaline phosphatase activity in D. magna. The inhibition of alkaline phosphatase by Roundup® was temperature-dependent with lowest inhibition at 14 °C and greater inhibition at 20 and 26 °C. Exposure of D. magna to sublethal concentrations of glyphosate...

  4. Lethal and sublethal effects of an insect growth regulator, pyriproxyfen, on obliquebanded leafroller (Lepidoptera: Tortricidae).

    Science.gov (United States)

    Sial, Ashfaq A; Brunner, Jay F

    2010-04-01

    The obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), is one of the most destructive pests of tree fruit in Washington. The development of insecticide resistance in C. rosaceana has led us to explore new management tactics. The use of very low doses of insecticides that have strong sublethal effects represents an environmentally friendly option to improve existing integrated pest management (IPM) strategies. We tested the insect growth regulator pyriproxyfen to determine its lethal and sublethal effects on growth and development of C. rosaceana. A leaf-disk bioassay was used to test seven concentrations of pyriproxyfen ranging from 0 to 30 ppm on fifth-instar C. rosaceana. Male and female larvae were assessed separately for mortality as well as other parameters of growth and development. The LC, values for males and females were 2.4 and 4.8 ppm, respectively. The response to pyriproxyfen was concentration-dependent: only 5-6% of the larvae treated with the highest concentration emerged as morphologically normal adults compared with 86% emergence in the controls. The pupation and adult emergence was significantly delayed at concentrations higher than 1 ppm. The weights of C. rosaceana pupae and adults were significantly increased, whereas fecundity and fertility were significantly reduced at a sublethal concentration of 0.3 ppm. We conclude that both lethal and sublethal effects might exhibit significant impacts on the population dynamics of C. rosaceana in tree fruit orchards treated with low concentrations of pyriproxyfen.

  5. RFID tracking of sublethal effects of two neonicotinoid insecticides on the foraging behavior of Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Christof W Schneider

    Full Text Available The development of insecticides requires valid risk assessment procedures to avoid causing harm to beneficial insects and especially to pollinators such as the honeybee Apis mellifera. In addition to testing according to current guidelines designed to detect bee mortality, tests are needed to determine possible sublethal effects interfering with the animal's vitality and behavioral performance. Several methods have been used to detect sublethal effects of different insecticides under laboratory conditions using olfactory conditioning. Furthermore, studies have been conducted on the influence insecticides have on foraging activity and homing ability which require time-consuming visual observation. We tested an experimental design using the radiofrequency identification (RFID method to monitor the influence of sublethal doses of insecticides on individual honeybee foragers on an automated basis. With electronic readers positioned at the hive entrance and at an artificial food source, we obtained quantifiable data on honeybee foraging behavior. This enabled us to efficiently retrieve detailed information on flight parameters. We compared several groups of bees, fed simultaneously with different dosages of a tested substance. With this experimental approach we monitored the acute effects of sublethal doses of the neonicotinoids imidacloprid (0.15-6 ng/bee and clothianidin (0.05-2 ng/bee under field-like circumstances. At field-relevant doses for nectar and pollen no adverse effects were observed for either substance. Both substances led to a significant reduction of foraging activity and to longer foraging flights at doses of ≥0.5 ng/bee (clothianidin and ≥1.5 ng/bee (imidacloprid during the first three hours after treatment. This study demonstrates that the RFID-method is an effective way to record short-term alterations in foraging activity after insecticides have been administered once, orally, to individual bees. We contribute further

  6. Sulfanegen Sodium Treatment in a Rabbit Model of Sub-Lethal Cyanide Toxicity

    Science.gov (United States)

    Brenner, Matthew; Kim, Jae G.; Lee, Jangwoen; Mahon, Sari B.; Lemor, Daniel; Ahdout, Rebecca; Boss, Gerry R.; Blackledge, William; Jann, Lauren; Nagasawa, Herbert T.; Patterson, Steven E.

    2010-01-01

    The aim of this study is to investigate the ability of intramuscular and intravenous sulfanegen sodium treatment to reverse cyanide effects in a rabbit model as a potential treatment for mass casualty resulting from cyanide exposure. Cyanide poisoning is a serious chemical threat from accidental or intentional exposures. Current cyanide exposure treatments, including direct binding agents, methemoglobin donors, and sulfur donors, have several limitations. Non-rhodanese mediated sulfur transferase pathways, including 3-mercaptopyruvate sulfurtransferase (3-MPST) catalyze the transfer of sulfur from 3-MP to cyanide, forming pyruvate and less toxic thiocyanate. We developed a water soluble 3-MP prodrug, 3-mercaptopyruvatedithiane (sulfanegen sodium), with the potential to provide a continuous supply of substrate for CN detoxification. In addition to developing a mass casualty cyanide reversal agent, methods are needed to rapidly and reliably diagnose and monitor cyanide poisoning and reversal. We use non-invasive technology, diffuse optical spectroscopy (DOS) and continuous wave near infrared spectroscopy (CWNIRS) to monitor physiologic changes associated with cyanide exposure and reversal. A total of 35 animals were studied. Sulfanegen sodium was shown to reverse the effects of cyanide exposure on oxyhemoglobin and deoxyhemoglobin rapidly, significantly faster than control animals when administered by intravenous or intramuscular routes. RBC cyanide levels also returned to normal faster following both intramuscular and intravenous sulfanegen sodium treatment than controls. These studies demonstrate the clinical potential for the novel approach of supplying substrate for non-rhodanese mediated sulfur transferase pathways for cyanide detoxification. DOS and CWNIRS demonstrated their usefulness in optimizing the dose of sulfanegen sodium treatment. PMID:20705081

  7. The Sublethal Effects of β-Ecdysterone, a Highly Active Compound from Achyranthes bidentata Blume, on Grape Phylloxera, Daktulosphaira vitifoliae Fitch.

    Directory of Open Access Journals (Sweden)

    Yongqiang Liu

    Full Text Available Grape phylloxera, Daktulosphaira vitifoliae (Fitch (Hemiptera, Phylloxeridae, is a very destructive insect pest of grapevines. Intercropping of Achyranthes bidentata Blume (f. Amaranthaceae and Vitis spp. grapevines can be useful to control this pest. In the present study, the toxicity of 22 compounds, known to be present in A. bidentata, to grape phylloxera was evaluated. All treatments were toxic towards grape phylloxera but the degree of toxicity differed between treatments. Among the 22 tested compounds, several of which proved toxic towards grape phylloxera. However β-ecdysterone had higher toxic effects against grape phylloxera, with LC50 values of 175.73 mg a.i. liter-1. In addition, we assessed the sublethal effects of LC10, LC20 and LC40 of β-ecdysterone on grape phylloxera. The fourth instar and adult developmental periods and total life span were significantly prolonged by LC40 of β-ecdysterone. Fecundity decreased when grape phylloxera were exposed to LC20 and LC40 of β-ecdysterone. In addition, LC40 of β-ecdysterone decreased the intrinsic rate of increase (rm and the finite rate of increase (λ and prolonged the population doubling time (DT. The net reproductive rate (R0 was significantly reduced by both the LC20 and LC40 β-ecdysterone treatments. Our results demonstrated that β-ecdysterone had higher toxic effects and significant sublethal effects on grape phylloxera, and showed potential control of grape phylloxera.

  8. Lethal and Sublethal Effects of Essential Oils From Artemisia khorassanica and Vitex pseudo-negundo Against Plodia interpunctella (Lepidoptera: Pyralidae).

    Science.gov (United States)

    Borzoui, Ehsan; Naseri, Bahram; Abedi, Zahra; Karimi-Pormehr, Mohammad Sadegh

    2016-10-01

    Plodia interpunctella (Hübner, 1813) is a polyphagous and key pest of different stored products worldwide. The lethal and sublethal effects of essential oils of Artemisia khorassanica Podl. and Vitex pseudo-negundo (Hausskn) were studied on P. interpunctella The chemical constituents of the essential oils were also assessed using gas chromatography-mass spectrometry. Assays showed that the fumigant toxicity of A. khorassanica (LC50: 9.60 µl/liter air) was higher than V. pseudo-negundo (LC50: 23.05 µl/liter air). Moreover, the speed of mortality caused by A. khorassanica oil (LT50: 2.07 h) was higher than V. pseudo-negundo (LT50: 3.11 h). To assess the sublethal effects of the essential oils, adult moths were exposed to the LC30 of each essential oil, and life table parameters and energy contents of the surviving P. interpunctella were studied. Exposure to sublethal concentration of A. khorassanica negatively affected the life table of P. interpunctella, and also the protein, lipid, and glycogen contents of the larvae that came from treated adults. Vitex pseudo-negundo also affected lipid, protein, and glycogen contents of P. interpunctella The intrinsic rate of increase (rm), finite rate of increase ([Formula: see text]), and doubling time (DT) were not significantly different between control and V. pseudo-negundo treatment. According with these results, both tested essential oils, especially one extracted from A. khorassanica, have potential applications for the integrated management of P. interpunctella. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Sub-lethal effects of essential oil of Lippia sidoides on drywood termite Cryptotermes brevis (Blattodea: Termitoidea).

    Science.gov (United States)

    Santos, Abraão Almeida; de Oliveira, Bruna Maria Santos; Melo, Carlisson Ramos; Lima, Ana Paula Santana; Santana, Emile Dayara Rabelo; Blank, Arie Fitzgerald; Picanço, Marcelo Coutinho; Araújo, Ana Paula Albano; Cristaldo, Paulo Fellipe; Bacci, Leandro

    2017-11-01

    The drywood termite Cryptotermes brevis (Walker, 1853) (Kalotermitidae) is one of the most important wood structural pest in the world. Substances from the secondary metabolism of plants (e.g., essential oils) have been considered an environmentally safer form of control for urban pests, such as termites. In the present study, we analyzed the lethal and sub-lethal effects of essential oil of Lippia sidoides and its major components on C. brevis pseudergates in two routes of exposure (contact and fumigation). The essential oil of L. sidoides and thymol were more toxic to C. brevis pseudergates when applied by contact (LD50 = 9.33 and 8.20µgmg(-1), respectively) and by fumigation (LC50 = 9.10 and 23.6µLL(-1), respectively). In general, treatments changed the individual and collective behaviors of C. brevis pseudergates, as well as the displacement and walking speed. The essential oil of L. sidoides and its major components showed a high potential to control C. brevis pseudergates, due to the bioactivity in the two routes of exposure and the sub-lethal effects on the behavior and walking, important activities for the cohesion of C. brevis colonies. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Comparative effects of insecticides with different mechanisms of action on Chrysoperla externa (Neuroptera: Chrysopidae): lethal, sublethal and dose-response effects.

    Science.gov (United States)

    Joao Zotti, Moises; Dionel Grutzmacher, Anderson; Heres Lopes, Isac; Smagghe, Guy

    2013-12-01

    The comprehensive knowledge that the delayed systemic and reproduction side effects can be even more deleterious than acute toxicity, has caused a shift in focus toward sublethal effects assessment on physiology and behavior of beneficial insects. In this study, we assessed the risks posed by some insecticides with different mode of action through lethal and delayed systemic sublethal effects on the pupation, adult emergence, and reproduction of the chrysopid Chrysoperla externa (Hagen, 1861; Neuroptera: Chrysopidae), an important predator in pest biological control. The maximum field recommended dose (MFRD) and twice (2×MFRD) for chlorantraniliprole, tebufenozide, and pyriproxyfen were harmless to C. externa. In contrast, all the tested chitin synthesis inhibitors (CSIs) were highly detrimental to the predator, despite of their lack of acute lethal toxicity. Therefore, the safety assumed by using IGRs toward beneficial insects is not valid for chrysopids. Dose-response data showed that although all CSIs have a similar mechanism of action, the relative extent of toxicity may differ (novaluron > lufenuron > teflubenzuron). For CSIs, the delayed systemic effects became obvious at adult emergence, where the predicted no observable effect dose (NOED) was 1/2 048 of the MFRD for novaluron (0.085 ng/insect), and 1/256 of the MFRD for both lufenuron (0.25 ng/insect) and teflubenzuron (0.6 ng/insect). Finally, this work emphasized the significance of performing toxicity risk assessments with an adequate posttreatment period to avoid underestimating the toxicities of insecticides, as the acute lethal toxicity assays may not provide accurate information regarding the long-range effects of hazardous compounds. © 2012 Institute of Zoology, Chinese Academy of Sciences.

  11. Assessment of sublethal effects of methoxyfenozide on oriental fruit Moth (Lepidoptera: Tortricidae).

    Science.gov (United States)

    Borchert, Daniel M; Walgenbach, James F; Kennedy, George G

    2005-06-01

    Sublethal effects of the insect growth regulator methoxyfenozide were examined in oriental fruit moth, Grapholita molesta (Busck), in laboratory and field studies. In laboratory studies, oriental fruit moth larvae reared on diet amended with 0.1 ppm methoxyfenozide developed at the same rate as larvae reared on untreated diet, and paired moths reared as larvae from the same treated or untreated diets exhibited similar fecundity and fertility. Population growth differences over multiple generations were used to examine sublethal effects of methoxyfenozide on population dynamics in the field. Multiple single-tree cages were placed over apple (Malus spp.) trees treated with two applications of methoxyfenozide (70 g [AI] /ha) and nontreated trees. Cages were infested at a single time point with virgin male and female oriental fruit moth adults, and population growth was evaluated by egg counts, shoot infestation, fruit damage, and larval counts over a 12-wk period. Significantly fewer eggs, larvae, and damaged fruit were found on methoxyfenozide-treated compared with nontreated trees in 2001. Observed population differences may have been a result of direct mortality to eggs and larvae of the first generation rather than sublethal effects. In 2002, no differences were observed between treatments, but a heavy rain event shortly after the early infestation impacted the experiment. A late moth release treatment was tested in 2002 to examine the effects of residual methoxyfenozide 55 d after initial application. Significantly fewer eggs were found in the methoxyfenozide treatment compared with the control, but no differences existed among treatments in shoot infestation, percentage of damaged fruit, or larval populations. It was concluded direct mortality of eggs and larvae exposed to methoxyfenozide rather than sublethal effects were most important in reduction of subsequent generations.

  12. Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

    NARCIS (Netherlands)

    Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

    2016-01-01

    The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure

  13. Acute and sublethal toxicity of seepage waters from garbage dumps to permanent cell lines and primary cultures of hepatocytes from rainbow trout (Oncorhynchus mykiss): a novel approach to environmental risk assessment for chemicals and chemical mixtures.

    Science.gov (United States)

    Zahn, T; Hauck, C; Holzschuh, J; Braunbeck, T

    1995-01-01

    In order to evaluate the suitability of cytopathological criteria in isolated fish hepatocytes as endpoints in (eco)toxicological research, liver cells isolated from rainbow trout (Oncorhynchus mykiss) by collagenase perfusion were exposed in vitro for up to 5 days to sublethal dilutions of two seepage water samples collected from garbage dumps. Hepatocytes were analysed with respect to acute (lactate dehydrogenase leakage) and sublethal toxicity (electron microscopy, stereology). In addition, acute toxicity (24 h) was tested in the piscine fibrocytic cell line R1 by means of crystal violet staining and neutral red retention. Acute toxicity in R1 cells and isolated hepatocytes could only be documented for sample I at dilutions of 1:2 and 1:4. This difference in toxicity could be corroborated by cytological alterations in isolated hepatocytes, which could be documented for dilutions of 1:100 and 1:8 in samples I and II, respectively. Ultrastructural changes were time- and dose-dependent and included reduction of hepatocellular volume, disturbance of intracellular compartmentation, modified heterochromatin distribution, transformation of rough endoplasmic reticulum into concentric membrane whorls, proliferation of lysosomes and cytoplasmic vacuoles, as well as reduction of hepatocellular glycogen. Although several hepatocellular reactions were found after exposure to either sample, the syndrome of ultrastructural alterations allowed clear differentiation between the two samples. Results illustrate that cytological effects far below macroscopically detectable damage can be discovered not only in intact fish, but also in fish cell culture systems. On the basis of the data presented, a multi-tiered test procedure for aquatic toxicity assessment exclusively based on tests with fish cell culture systems is proposed: (1) rapid screening for acute toxicity with permanent cell lines; (2) short-term tests with more complex, yet more sensitive systems such as primary

  14. Sublethal effects of copper on some biological traits of the amphipod Gammarus aequicauda reared under laboratory conditions.

    Science.gov (United States)

    Prato, E; Parlapiano, I; Biandolino, F

    2013-10-01

    The common and widespread copper contamination in marine coastal environments make toxicity data necessary to assess the aquatic hazard and risk of this metal. In the present study, the sublethal effects of copper on survival, growth and reproduction of Gammarus aequicauda were investigated. Amphipods were exposed for 77d to 2 nominal copper concentrations (50, 100 μg L(-1)). Survival was the most sensitive measure of effect and was significantly reduced, especially during early life stage (juveniles). Growth of amphipods was also negatively affected by copper and the growth impairment in G. aequicauda increases with increasing metal concentration. The reproductive traits were impaired by each of the copper concentrations, even if there were not any significant differences between control and copper treatments. The size at maturity increased with increasing copper, so the smallest ovigerous females in the control and copper treatments were 0.83 mm and 1.35 mm head length, respectively. There was a positive correlation between the brood size and the body size of the female in all treatments, whilst the fecundity (n°juveniles/female) decreased in the order control, 50 and 100 μg Cu L(-1). Copper demonstrates chronic toxicity to G. aequicauda at realistic environmental concentrations. The results of this study entail that the understanding of chronic toxicity of a substance, especially on population level effects, is crucial to assess the long-term effect of the substance in the ecosystem. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Lethal and sub-lethal effects of copper to the african catfish ( clarias ...

    African Journals Online (AJOL)

    Lethal and sub-lethal effects of copper on Clarias gariepinus were studied using a 96-hour static bioassay. Copper (as copper chloride, CuCl2 . H2O) was used to prepare the stock solution from which five standard concentrations 0.0, 1.8, 3.2, 5.6, and 10.0 mg/L were prepared (coded A – E). 15 juvenile C. gariepinus fish ...

  16. Sublethal effects of some botanical and chemical insecticides on the cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-09-01

    Full Text Available In addition to direct mortalities caused by acute concentrations of insecticides, some biological traits of target pests may be also affected by sublethal doses. The cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae is an important pest of a wide variety of agricultural crops across the world. The control of B. tabaci largely relies on wide application of chemical insecticides. In this study, we analyzed the life table parameters to evaluate the sublethal effect of three plant-derived insecticides (Fumaria parviflora (Fumariaceae, Teucrium polium (Lamiaceae, and Thymus vulgaris (Lamiaceae and two chemical insecticides (pymetrozin and neemarin on B. tabaci. The whiteflies were allowed to oviposit on plants infected with each of the five insecticides using leaf-dip method. The data were analyzed using the age-stage two-sex life table. We found significant differences in the gross reproductive rate (GRR, the net reproductive rat (R0, the intrinsic rate of increase (r and the finite rate of increase (λ of treated whiteflies compared to control. Our results showed that some biological traits of B. tabaci are affected by sub-lethal doses of the plant-derived extracts and that these effects are comparable to those of chemical insecticides. Given the detrimental effects of chemical insecticides on human, environment and non-target organisms, plant-derived insecticides may provide valuable environmentally friendly tools for pest management programs.

  17. Sublethal effects of spinetoram on the two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae).

    Science.gov (United States)

    Wang, Ling; Zhang, Youjun; Xie, Wen; Wu, Qingjun; Wang, Shaoli

    2016-09-01

    The two-spotted spider mite Tetranychus urticae is a serious pest of many agricultural crops and ornamental plants. The sublethal effects of a new chemical, spinetoram, on T. urticae were investigated by treating adult females and eggs with LC10 and LC20 in the laboratory. The data were assessed based on age-stage, two-sex life table analysis. The results showed that T. urticae developmental time from egg to adult was reduced and that fecundity was increased by treatment with LC10 and LC20 of spinetoram. The LC10 and LC20 of spinetoram also increased the intrinsic and finite rate of increase and the net reproductive rate and reduced the mean generation time, egg duration, and larval duration whether eggs or adult females were treated. These laboratory results suggest that sublethal or lethal doses of spinetoram may cause outbreaks of T. urticae. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Effect of non-homogenous thermal stress during sub-lethal photodynamic antimicrobial chemotherapy

    Science.gov (United States)

    Gadura, N.; Kokkinos, D.; Dehipawala, S.; Cheung, E.; Sullivan, R.; Subramaniam, R.; Schneider, P.; Tremberger, G., Jr.; Holden, T.; Lieberman, D.; Cheung, T.

    2012-03-01

    Pathogens could be inactivated via a light source coupled with a photosensitizing agent in photodynamic antimicrobial chemotherapy (PACT). This project studied the effect of non-homogenous substrate on cell colony. The non-homogeneity could be controlled by iron oxide nano-particles doping in porous glassy substrates such that each cell would experience tens of hot spots when illuminated with additional light source. The substrate non-homogeneity was characterized by Atomic Force Microscopy, Transmission Electron Microscopy and Extended X-Ray Absorption Fine Structure at Brookhaven Synchrotron Light Source. Microscopy images of cell motion were used to study the motility. Laboratory cell colonies on non-homogenous substrates exhibit reduced motility similar to those observed with sub-lethal PCAT treatment. Such motility reduction on non-homogenous substrate is interpreted as the presence of thermal stress. The studied pathogens included E. coli and Pseudomonas aeruginosa. Non-pathogenic microbes Bacillus subtilis was also studied for comparison. The results show that sub-lethal PACT could be effective with additional non-homogenous thermal stress. The use of non-uniform illumination on a homogeneous substrate to create thermal stress in sub-micron length scale is discussed via light correlation in propagation through random medium. Extension to sub-lethal PACT application complemented with thermal stress would be an appropriate application.

  19. Lethal and sub-lethal effects of elevated CO2 concentrations on marine benthic invertebrates and fish.

    Science.gov (United States)

    Lee, Changkeun; Hong, Seongjin; Kwon, Bong-Oh; Lee, Jung-Ho; Ryu, Jongseong; Park, Young-Gyu; Kang, Seong-Gil; Khim, Jong Seong

    2016-08-01

    Concern about leakage of carbon dioxide (CO2) from deep-sea storage in geological reservoirs is increasing because of its possible adverse effects on marine organisms locally or at nearby coastal areas both in sediment and water column. In the present study, we examined how elevated CO2 affects various intertidal epibenthic (benthic copepod), intertidal endobenthic (Manila clam and Venus clam), sub-tidal benthic (brittle starfish), and free-living (marine medaka) organisms in areas expected to be impacted by leakage. Acute lethal and sub-lethal effects were detected in the adult stage of all test organisms exposed to varying concentrations of CO2, due to the associated decline in pH (8.3 to 5.2) during 96-h exposure. However, intertidal organisms (such as benthic copepods and clams) showed remarkable resistance to elevated CO2, with the Venus clam being the most tolerant (LpH50 = 5.45). Sub-tidal species (such as brittle starfish [LpH50 = 6.16] and marine medaka [LpH50 = 5.91]) were more sensitive to elevated CO2 compared to intertidal species, possibly because they have fewer defensive capabilities. Of note, the exposure duration might regulate the degree of acute sub-lethal effects, as evidenced by the Venus clam, which showed a time-dependent effect to elevated CO2. Finally, copper was chosen as a model toxic element to find out the synergistic or antagonistic effects between ocean acidification and metal pollution. Combination of CO2 and Cu exposure enhances the adverse effects to organisms, generally supporting a synergistic effect scenario. Overall, the significant variation in the degree to which CO2 adversely affected organisms (viz., working range and strength) was clearly observed, supporting the general concept of species-dependent effects of elevated CO2.

  20. Effects of sublethal exposure to metofluthrin on the fitness of Aedes aegypti in a domestic setting in Cairns, Queensland

    OpenAIRE

    Buhagiar, Tamara S.; Gregor J Devine; Scott A. Ritchie

    2017-01-01

    Background Metofluthrin is highly effective at reducing biting activity in Aedes aegypti. Its efficacy lies in the rapid onset of confusion, knockdown, and subsequent kill of a mosquito. In the field, there are a variety of scenarios that might result in sublethal exposure to metofluthrin, including mosquitoes that are active at the margins of the chemical?s lethal range, brief exposure as mosquitoes fly in and out of treated spaces or decreasing efficacy of the emanators with time. Sublethal...

  1. Sublethal Effects of Diesel on Total Protein Levels and Cholesterol ...

    African Journals Online (AJOL)

    Michael Horsfall

    and from the hydrophobic nature of the oil (Osuji and. Mbata, 2004). Oil in contact ... The various effects revealed with biomarkers can therefore be applied in regulatory decision making and environmental management (Ewald, 1995). This study was .... architecture (Singh et al., 2010) and therefore any interference with this ...

  2. Sublethal effects on wood frogs chronically exposed to environmentally relevant concentrations of two neonicotinoid insecticides.

    Science.gov (United States)

    Robinson, Stacey A; Richardson, Sarah D; Dalton, Rebecca L; Maisonneuve, France; Trudeau, Vance L; Pauli, Bruce D; Lee-Jenkins, Stacey S Y

    2017-04-01

    Neonicotinoids are prophylactically used globally on a variety of crops, and there is concern for the potential impacts of neonicotinoids on aquatic ecosystems. The intensive use of pesticides on crops has been identified as a contributor to population declines of amphibians, but currently little is known regarding the sublethal effects of chronic neonicotinoid exposure on amphibians. The objective of the present study was to characterize the sublethal effect(s) of exposure to 3 environmentally relevant concentrations (1 μg/L, 10 μg/L, and 100 μg/L) of 2 neonicotinoids on larval wood frogs (Lithobates sylvaticus) using outdoor mesocosms. We exposed tadpoles to solutions of 2 commercial formulations containing imidacloprid and thiamethoxam, and assessed survival, growth, and development. Exposure to imidacloprid at 10 μg/L and 100 μg/L increased survival and delayed completion of metamorphosis compared with controls. Exposure to thiamethoxam did not influence amphibian responses. There was no significant effect of any treatment on body mass or size of the metamorphs. The results suggest that current usage of imidacloprid and thiamethoxam does not pose a threat to wood frogs. However, further assessment of both direct and indirect effects on subtle sublethal endpoints, and the influence of multiple interacting stressors at various life stages, is needed to fully understand the effects of neonicotinoids on amphibians. Environ Toxicol Chem 2017;36:1101-1109. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

  3. Busulfan administration produces sublethal effects on somatic tissues and inhibits gametogenesis in Senegalese sole juveniles.

    Science.gov (United States)

    Pacchiarini, T; Olague, E; Sarasquete, C; Cabrita, E

    2014-05-01

    Busulfan, a cytotoxic alkylating agent used for treatment of chronic myeloid leukemia has effects in mammalian germ cells. In fish species, the use of this compound is of special interest in intra and interspecies germ cell transplants. To determine the effects of busulfan in fish a previous range finding experiment was designed. Survival and growth rate of 150-days after hatching (150DAH) Senegalese sole (Solea senegalensis) juveniles was determined. In a second experiment, the effects of a sublethal busulfan dose in fish germ cell depletion and in somatic tissues were analysed. Sublethal effects of several busulfan treatments (B10-10 days after injection, B20-20 days after injection, B20÷-20 days after injection with double injection) were determined in somatic and gonadal tissues. Alterations were registered through histopathological techniques, TUNEL (cell apoptosis) and quantified at molecular level (Q-PCR analyses) using the vasa mRNAs (Ssvasa1-2 and Ssvasa3-4 mRNAs) as molecular markers for germinal cells in Senegalese sole juveniles. Several sublethal effects were observed with 40 mg kg⁻¹ busulfan, a non-lethal dose, such as: pyknosis in liver, increase of melanomacrophage centres and blood stagnation in spleen and interruption of gonadal development. Females were more affected by busulfan treatments than males in terms of germ cell disruption, since a significant decrease in the expression of both Ssvasa1-2 and Ssvasa3-4 markers was found in the gonad of treated females rather than males. At 10 days post-treatment (B10), females already presented a decrease in germ cell proliferation, as confirmed by Q-PCR. Ssvasa expression proved to be a reliable tool for the direct evaluation of the effects of busulfan on Senegalese sole gonadal development, proving that busulfan can be a suitable treatment for causing transient sterility in recipient gonads for germ cell transplantation.

  4. Sublethal imidacloprid effects on honey bee flower choices when foraging.

    Science.gov (United States)

    Karahan, Ahmed; Çakmak, Ibrahim; Hranitz, John M; Karaca, Ismail; Wells, Harrington

    2015-11-01

    Neonicotinoids, systemic neuro-active pesticides similar to nicotine, are widely used in agriculture and are being investigated for a role in honey bee colony losses. We examined one neonicotinoid pesticide, imidacloprid, for its effects on the foraging behavior of free-flying honey bees (Apis mellifera anatoliaca) visiting artificial blue and white flowers. Imidacloprid doses, ranging from 1/5 to 1/50 of the reported LD50, were fed to bees orally. The study consisted of three experimental parts performed sequentially without interruption. In Part 1, both flower colors contained a 4 μL 1 M sucrose solution reward. Part 2 offered bees 4 μL of 1.5 M sucrose solution in blue flowers and a 4 μL 0.5 M sucrose solution reward in white flowers. In Part 3 we reversed the sugar solution rewards, while keeping the flower color consistent. Each experiment began 30 min after administration of the pesticide. We recorded the percentage of experimental bees that returned to forage after treatment. We also recorded the visitation rate, number of flowers visited, and floral reward choices of the bees that foraged after treatment. The forager return rate declined linearly with increasing imidacloprid dose. The number of foraging trips by returning bees was also affected adversely. However, flower fidelity was not affected by imidacloprid dose. Foragers visited both blue and white flowers extensively in Part 1, and showed greater fidelity for the flower color offering the higher sugar solution reward in Parts 2 and 3. Although larger samples sizes are needed, our study suggests that imidacloprid may not affect the ability to select the higher nectar reward when rewards were reversed. We observed acute, mild effects on foraging by honey bees, so mild that storage of imidacloprid tainted-honey is very plausible and likely to be found in honey bee colonies.

  5. {sup 1}H NMR-based metabolomics reveals sub-lethal toxicity of a mixture of diabetic and lipid-regulating pharmaceuticals on amphibian larvae

    Energy Technology Data Exchange (ETDEWEB)

    Melvin, Steven D., E-mail: s.melvin@griffith.edu.au [Australian Rivers Institute, Griffith University, Southport, QLD 4222 (Australia); Habener, Leesa J. [Griffith School of Environment, Griffith University, Southport, QLD 4222 (Australia); Leusch, Frederic D.L. [Australian Rivers Institute, Griffith University, Southport, QLD 4222 (Australia); Griffith School of Environment, Griffith University, Southport, QLD 4222 (Australia); Carroll, Anthony R. [Griffith School of Environment, Griffith University, Southport, QLD 4222 (Australia)

    2017-03-15

    Highlights: • Pharmaceutical pollutants are a concern for eliciting adverse effects in wildlife. • Diabetes and lipid regulating drugs are widely used and poorly removed from sewage. • We explored the toxicity of a mixture of metformin, atorvastatin and bezafibrate on tadpoles. • Exposure caused increased growth and development but no effects on lipids or cholesterol. • {sup 1}H NMR-based metabolomics reveal increased lactic acid and BCAAs in exposed animals. - Abstract: Pharmaceuticals are widely used for the treatment of various physical and psychological ailments. Due to incomplete removal during sewage treatment many pharmaceuticals are frequently detected in aquatic waterways at trace concentrations. The diversity of pharmaceutical contaminants and potential for complex mixtures to occur makes it very difficult to predict the toxicity of these compounds on wildlife, and robust methods are therefore needed to explore sub-lethal effects. Metabolic syndrome is one of the most widespread health concerns currently facing the human population, and various drugs, including anti-diabetic medications and lipid- and cholesterol-lowering fibrates and statins, are widely prescribed as treatment. In this study, we exposed striped marsh frog (Limnodynastes peronii) tadpoles to a mixture of the drugs metformin, atorvastatin and bezafibrate at 0.5, 5, 50 and 500 μg/L to explore possible effects on growth and development, energy reserves (triglycerides and cholesterol), and profiles of small polar metabolites extracted from hepatic tissues. It was hypothesised that exposure would result in a general reduction in energy reserves, and that this would subsequently correspond with reduced growth and development. Responses differed from expected outcomes based on the known mechanisms of these compounds in humans, with no changes to hepatic triglycerides or cholesterol and a general increase in mass and condition with increasing exposure concentration. Deviation from the

  6. Lethal and sub-lethal effects of the fungicide chlorothalonil on three life stages of the grass shrimp, Palaemonetes pugio.

    Science.gov (United States)

    Key, Peter B; Meyer, Shelli L; Chung, Katy W

    2003-09-01

    Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is the second most widely used fungicide in the United States. Due to the widespread use of chlorothalonil, it is important to investigate the effects chlorothalonil may have on estuarine species such as the grass shrimp, Palaemonetes pugio. This study examined the toxicity of chlorothalonil to three life-history stages (embryo, larvae, adult) of the grass shrimp. Also, molting frequency, growth response and metamorphosis from a larval life cycle pulsed exposure assay were examined as sub-lethal indicators of chlorothalonil exposure. Results showed embryos were the least sensitive with a 96-h Median Lethal Concentration (LC50) of 396.0 microg/L (95% Confidence Interval [CI] 331.3-472.4 microg/L). The adult 96-h LC50 was 152.9 microg/L (95% CI 120.3-194.5 microg/L). Larvae were the most sensitive to chlorothalonil exposure with a 96-h LC50 of 49.5 microg/L (95% CI 44.4-55.27 microg/L). In the life cycle pulsed exposure assay, all surviving larvae in the treatments required significantly more molts to reach postlarvae than the control. Other measured parameters showed differences between treatments and control but there was no statistical significance. This research demonstrated that chlorothalonil is highly toxic to grass shrimp and that larval grass shrimp would be the most appropriate life stage to use for chlorothalonil risk assessments since that stage is the most sensitive.

  7. Histopathological effect of sub-lethal concentration of aluminum phosphide (phostoxin on Clarias gariepinus juveniles

    Directory of Open Access Journals (Sweden)

    Kayode B. Olurin

    Full Text Available Abtsract: The study evaluated the effect of sub-lethal concentration of phostoxin on Clarias gariepinus juveniles. C. gariepinus juveniles belonging to the same cohort (40.1±1.2g; 18.1±1.1cm from a commercial fish farm were randomly placed ten in each of 15 plastic tanks containing 15 liters of water. They were exposed for 96 hrs to three sub-lethal concentrations (treatments of phostoxin (0.125, 0.250, 0.5mg L-1 and a phostoxin free control. At the end of 96 hrs exposure, they were dissected and the tissues need for histopathology removed and fixed in Bouin's fluid. The gill filament exhibited fusion at the secondary lamella that was progressive with concentration. At the highest concentration of exposure, the secondary lamellae showed marked pyknotic and necrotic changes characterized by epithelia detachment. The hepatic tissue showed mild inflammatory changes at lower concentrations while at the highest concentration of exposure there was marked inflammation with observed hydropic degeneration. In the kidney, an inflammatory change was only observed in the interstices at the highest dose of exposure with the convoluted tubules showing partial shrinkage. Phostoxin showed to have significantly caused alterations in cyto-architecture of the gills and to a considerable extent liver and kidney of C. gariepinus.

  8. Effects of Glyphosate-Based Herbicide Sub-Lethal Concentrations on Fish Feeding Behavior.

    Science.gov (United States)

    Giaquinto, Percilia Cardoso; de Sá, Marina Borges; Sugihara, Vanessa Seiko; Gonçalves, Bruno Bastos; Delício, Helton Carlos; Barki, Assaf

    2017-04-01

    Glyphosate-based herbicides are widely used in agricultural systems. Although the target organism are particularly plant organisms, there are numerous studies showing adverse effects in aquatic animals, such as inhibition of acetyl cholinesterase, effects on kidney, liver, and gill and stressors effects. This study analyzed the effects of commercial formulation of glyphosate on feeding behavior in Pacu (Piaractus mesopotamicus). Fish were exposed to three glyphosate concentrations (0.2, 0.6, and 1.8 ppm) for 15 days. At concentrations of 0.2 and 0.6 ppm, food intake decreased on day 13 and then returned to normal on day 15. At the highest glyphosate-based herbicide concentration, 1.8 ppm, food consumption decreased dramatically and did not recover on day 15. This study showed that glyphosate-based herbicide at sub-lethal concentrations can affect feed intake in pacu and consequently inhibits its growth.

  9. Feeding Inhibition: the Ups and Downs of Sublethal Effects on Grazers and Detritivores

    Science.gov (United States)

    Alexander, A.; Culp, J.; Liber, K.; Baird, D.

    2005-05-01

    Sublethal impacts are likely the primary mechanism of exposure for the aquatic community in the case of soluble agricultural pesticides. This study examines the effects of pulsed exposures of the common insecticide, imidacloprid, on the feeding and growth of the mayfly Epeorus longimanus, and the oligochaete, Lumbriculus variegatus. Examining the effects of pulsed exposures of imidacloprid is particularly relevant due to the soluble (0.51g/L) nature of this compound. Recovery experiments were conducted by exposing mayflies and oligochaetes to an environmentally realistic range (0, 0.1, 0.5, 1, 5, 10 ppb) of concentrations for a short period. Effects on feeding were measured by quantifying the foodstuffs consumed by mayflies and egested by oligochaetes. In tandem with the feeding experiments, a series of artificial stream experiments were undertaken that demonstrate the changes in growth and abundance of adult mayflies in response to this common insecticide stressor.

  10. Maternal transfer and sublethal immune system effects of brevetoxin exposure in nesting loggerhead sea turtles (Caretta caretta) from western Florida.

    Science.gov (United States)

    Perrault, Justin R; Bauman, Katherine D; Greenan, Taylor M; Blum, Patricia C; Henry, Michael S; Walsh, Catherine J

    2016-11-01

    Blooms of Karenia brevis (also called red tides) occur almost annually in the Gulf of Mexico. The health effects of the neurotoxins (i.e., brevetoxins) produced by this toxic dinoflagellate on marine turtles are poorly understood. Florida's Gulf Coast represents an important foraging and nesting area for a number of marine turtle species. Most studies investigating brevetoxin exposure in marine turtles thus far focus on dead and/or stranded individuals and rarely examine the effects in apparently "healthy" free-ranging individuals. From May-July 2014, one year after the last red tide bloom, we collected blood from nesting loggerhead sea turtles (Caretta caretta) on Casey Key, Florida USA. These organisms show both strong nesting and foraging site fidelity. The plasma was analyzed for brevetoxin concentrations in addition to a number of health and immune-related parameters in an effort to establish sublethal effects of this toxin. Lastly, from July-September 2014, we collected unhatched eggs and liver and yolk sacs from dead-in-nest hatchlings from nests laid by the sampled females and tested these samples for brevetoxin concentrations to determine maternal transfer and effects on reproductive success. Using a competitive enzyme-linked immunosorbent assay (ELISA), all plasma samples from nesting females tested positive for brevetoxin (reported as ng brevetoxin-3[PbTx-3] equivalents [eq]/mL) exposure (2.1-26.7ng PbTx-3eq/mL). Additionally, 100% of livers (1.4-13.3ng PbTx-3eq/mL) and yolk sacs (1.7-6.6ng PbTx-3eq/mL) from dead-in-nest hatchlings and 70% of eggs (<1.0-24.4ng PbTx-3eq/mL) tested positive for brevetoxin exposure with the ELISA. We found that plasma brevetoxin concentrations determined by an ELISA in nesting females positively correlated with gamma-globulins, indicating a potential for immunomodulation as a result of brevetoxin exposure. While the sample sizes were small, we also found that plasma brevetoxin concentrations determined by an ELISA in

  11. Field-level sublethal effects of approved bee hive chemicals on Honey Bees (Apis mellifera L).

    Science.gov (United States)

    Berry, Jennifer A; Hood, W Michael; Pietravalle, Stéphane; Delaplane, Keith S

    2013-01-01

    In a study replicated across two states and two years, we tested the sublethal effects on honey bees of the miticides Apistan (tau fluvalinate) and Check Mite+ (coumaphos) and the wood preservative copper naphthenate applied at label rates in field conditions. A continuous covariate, a colony Varroa mite index, helped us disambiguate the effects of the chemicals on bees while adjusting for a presumed benefit of controlling mites. Mite levels in colonies treated with Apistan or Check Mite+ were not different from levels in non-treated controls. Experimental chemicals significantly decreased 3-day brood survivorship and increased construction of queen supercedure cells compared to non-treated controls. Bees exposed to Check Mite+ as immatures had higher legacy mortality as adults relative to non-treated controls, whereas bees exposed to Apistan had improved legacy mortality relative to non-treated controls. Relative to non-treated controls, Check Mite+ increased adult emergence weight. Although there was a treatment effect on a test of associative learning, it was not possible to statistically separate the treatment means, but bees treated with Apistan performed comparatively well. And finally, there were no detected effects of bee hive chemical on colony bee population, amount of brood, amount of honey, foraging rate, time required for marked released bees to return to their nest, percentage of released bees that return to the nest, and colony Nosema spore loads. To our knowledge, this is the first study to examine sublethal effects of bee hive chemicals applied at label rates under field conditions while disambiguating the results from mite control benefits realized from the chemicals. Given the poor performance of the miticides at reducing mites and their inconsistent effects on the host, these results defend the use of bee health management practices that minimize use of exotic hive chemicals.

  12. Field-level sublethal effects of approved bee hive chemicals on Honey Bees (Apis mellifera L.

    Directory of Open Access Journals (Sweden)

    Jennifer A Berry

    Full Text Available In a study replicated across two states and two years, we tested the sublethal effects on honey bees of the miticides Apistan (tau fluvalinate and Check Mite+ (coumaphos and the wood preservative copper naphthenate applied at label rates in field conditions. A continuous covariate, a colony Varroa mite index, helped us disambiguate the effects of the chemicals on bees while adjusting for a presumed benefit of controlling mites. Mite levels in colonies treated with Apistan or Check Mite+ were not different from levels in non-treated controls. Experimental chemicals significantly decreased 3-day brood survivorship and increased construction of queen supercedure cells compared to non-treated controls. Bees exposed to Check Mite+ as immatures had higher legacy mortality as adults relative to non-treated controls, whereas bees exposed to Apistan had improved legacy mortality relative to non-treated controls. Relative to non-treated controls, Check Mite+ increased adult emergence weight. Although there was a treatment effect on a test of associative learning, it was not possible to statistically separate the treatment means, but bees treated with Apistan performed comparatively well. And finally, there were no detected effects of bee hive chemical on colony bee population, amount of brood, amount of honey, foraging rate, time required for marked released bees to return to their nest, percentage of released bees that return to the nest, and colony Nosema spore loads. To our knowledge, this is the first study to examine sublethal effects of bee hive chemicals applied at label rates under field conditions while disambiguating the results from mite control benefits realized from the chemicals. Given the poor performance of the miticides at reducing mites and their inconsistent effects on the host, these results defend the use of bee health management practices that minimize use of exotic hive chemicals.

  13. Lethal and Sublethal Effects of Glyphosate (Roundup® Active to Embryos of Colombian Anurans

    Directory of Open Access Journals (Sweden)

    Teófila María Triana Velásquez

    2013-05-01

    Full Text Available Glyphosate is an herbicide widely used in agriculture, which may affect non-target species. The aim of this study was to determine the lethal (Median lethal concentration - LC50 and sublethal effects (changes on body size and development of glyphosate (Roundup® Active to embryos of four anuran species, exposed during 96 hours under laboratory and microcosm tests. Under laboratory conditions, Engystomops pustulosus was the most tolerant species (LC50 = 3033,18 μg a.e./L and Rhinella marina was the most sensitive (LC50 = 1421,46 μg a.e./L, which also showed a delayed development and significantly reduced body size. The other species had an intermediate LC50 (Rhinella humboldti = 2899,54 μg a.e./L; Hypsiboas crepitans = 2151,88 μg a.e./L. In all cases, the laboratory LC50 was lower than the concentration used in field (5392,92 μg a.e./L, indicating a high toxic effect. In the microcosm tests, embryos of E. pustulosus were the most tolerant (LC50 = 19,41 kg a.e./ha, while R. humboldti were the most sensitive (LC50 = 10,61 kg a.e./ha. In this case, all four study species had a higher LC50 than the concentration sprayed in field (3,69 kg a.e./ ha, so a lower lethal effect, and there were no significant differences in body size and development. This result shows that the glyphosate, as the commercial presentation Roundup® Active, produce a moderate mortality on anuran embryos.EFECTOS LETALES Y SUBLETALES DEL GLIFOSATO (ROUNDUP® ACTIVO EN EMBRIONES DE ANUROS COLOMBIANOS.El glifosato es un herbicida usado en la agricultura que puede afectar especies no blanco. El objetivo del trabajo fue determinar los efectos letales (concentración letal media - CL50 y subletales (cambios en el tamaño corporal y desarrollo del glifosato (Roundup® Activo sobre embriones de cuatro especies de anuros expuestos durante 96 horas en pruebas de laboratorio y microcosmos. En laboratorio, la especie más tolerante fue Engystomops pustulosus (CL50 = 3033,18 μg a

  14. Sublethal effect of imidacloprid on Solenopsis invicta (Hymenoptera: Formicidae) feeding, digging, and foraging behavior

    Science.gov (United States)

    There is increasing evidence that exposure to neonicotinoid insecticides at sublethal levels impairs colonies of honeybee and other pollinators. Recently, it was found that sublethal contamination with neonicotinoids also affect growth and behavior of ants. In this study, we exposed red imported fi...

  15. Effects of sublethal entrainment stresses on the vulnerability of juvenile bluegill sunfish to predation

    Energy Technology Data Exchange (ETDEWEB)

    Cada, G.F.; Solomon, J.A.; Loar, J.M.

    1981-07-01

    This report provides a review of literature concerning the effects of sublethal stresses on predator-prey interactions in aquatic systems. In addition, the results of a preliminary laboratory study of the susceptibility of entrainment-stressed juvenile bluegill to striped bass predation are presented. Juvenile bluegill were exposed to thermal and physical entrainment stresses in the ORNL Power Plant Simulator and subsequently to predation by juvenile striped bass in a susceptibility to predation experimental design. None of the entrainment stresses tested (thermal shock, physical effects of pump and condenser passage, and combination of thermal and physical shock) was found to significantly increase predation rates as compared to controls, and no significant interactions between thermal and physical stresses were detected. The validity of laboratory predator-prey studies and the application of indirect mortality information for setting protective standards and predicting environmental impacts are discussed.

  16. Mortality, Temporary Sterilization, and Maternal Effects of Sublethal Heat in Bed Bugs

    Science.gov (United States)

    Rukke, Bjørn Arne; Aak, Anders; Edgar, Kristin Skarsfjord

    2015-01-01

    Adult bed bugs were exposed to the sublethal temperatures 34.0°C, 35.5°C, 37.0°C, 38.5°C, or 40.0°C for 3, 6, or 9 days. The two uppermost temperatures induced 100% mortality within 9 and 2 days, respectively, whereas 34.0°C had no observable effect. The intermediate temperatures interacted with time to induce a limited level of mortality but had distinct effects on fecundity, reflected by decreases in the number of eggs produced and hatching success. Adult fecundity remained low for up to 40 days after heat exposure, and the time until fertility was restored correlated with the temperature-sum experienced during heat exposure. Three or 6 days of parental exposure to 38.5°C significantly lowered their offspring’s feeding and moulting ability, which consequently led to a failure to continue beyond the third instar. Eggs that were deposited at 22.0°C before being exposed to 37.0°C for 3 or 6 days died, whereas eggs that were exposed to lower temperatures were not significantly affected. Eggs that were deposited during heat treatment exhibited high levels of mortality also at 34.0°C and 35.5°C. The observed negative effects of temperatures between 34.0°C and 40.0°C may be utilized in pest management, and sublethal temperature exposure ought to be further investigated as an additional tool to decimate or potentially eradicate bed bug populations. The effect of parental heat exposure on progeny demonstrates the importance of including maternal considerations when studying bed bug environmental stress reactions. PMID:25996999

  17. Sublethal effects of Imidacloprid on honey bee colony growth and activity at three sites in the U.S.

    Science.gov (United States)

    Field experiments in southern Arizona, central Arkansas and southern Mississippi were conducted to evaluate the effects of sublethal concentrations (0, 5, 20 and 100 ppb) of imidacloprid in sugar syrup on honey bee colony growth and activity. Response variables included discrete data from hive inspe...

  18. Protective effect of milk constituents and sublethal injuries limiting process effectiveness during PEF inactivation of Lb. rhamnosus.

    Science.gov (United States)

    Jaeger, H; Schulz, A; Karapetkov, N; Knorr, D

    2009-08-31

    The inactivation of Lb. rhamnosus by pulsed electric field treatment (PEF) was studied in different fractions of raw milk and Ringer solution in order to evaluate the protective effect of nutrient rich media in comparison to aqueous buffer solutions. Apart from monitoring of culturability, analysis of the physiological fitness of Lb. rhamnosus was conducted aiming to identify sublethally damaged cells. Therefore, flow cytometry and a selective medium plating technique were used and compared to each other. The goal of the study was to apply three different parameters describing the physiological fitness of the model organism Lb. rhamnosus after PEF treatment such as culturability, membrane permeability and metabolic activity depending on treatment media and parameters. A concentration dependent protective effect of the milk protein fraction could be shown and allocated to micellar casein as the major milk protein. Increasing the concentration of whey proteins up to 2% showed a similar impact on limiting the PEF inactivation of Lb. rhamnosus. The evaluation of physiological fitness of cells was based on a determination of structural and functional characteristics by rapid cellular staining using carboxyfluorescein diacetate and propidium iodide. This approach showed good accordance to the conventional selective medium plating technique for the enumeration of sublethally-injured bacteria but flow cytometry provided additional information for the characterisation of this fraction. The extent of occurrence of dead, sublethal and vital fractions of cells was found dependent on the PEF treatment parameters such as electrical field strength and energy input as well as the different milk fractions used as treatment media.

  19. Sub-lethal effects of four neonicotinoid seed treatments on the demography and feeding behaviour of the wheat aphid Sitobion avenae.

    Science.gov (United States)

    Miao, Jin; Du, Zhen-Bao; Wu, Yu-Qing; Gong, Zhong-Jun; Jiang, Yue-Li; Duan, Yun; Li, Tong; Lei, Chao-Liang

    2014-01-01

    Neonicotinoids are widely used as seed treatments in wheat fields against the grain aphid (Sitobion avenae F.) in China. Due to the degradation of neonicotinoids in wheat plants, wheat aphids are more likely to be exposed to low concentrations of neonicotinoids over long periods. It is therefore expected that neonicotinoids, aside from acute (lethal) effects, may also cause a range of sub-lethal effects on this pest. The growth and fertility of S. avenae feeding on wheat plants treated with a sub-lethal concentration (LC10 ) of imidacloprid, dinotefuran, thiacloprid and thiamethoxam were not greatly affected. However, the population growth parameters of S. avenae were significantly reduced at median lethal concentration (LC50 ). Electronic penetration graph recordings showed a higher percentage of no probing phase and shorter phloem sap ingestion phase on the wheat plants treated with LC10 and LC50 concentrations. The results indicate that even low concentrations of neonicotinoid treatments on wheat seeds have long-term, adverse effects on wheat aphid. As such, neonicotinoid seed treatments have far greater effects on wheat aphids than estimated by acute toxicity tests. These results benefit our understanding on the subtle effects of the four tested neonicotinoids when applied as seed treatments. © 2013 Society of Chemical Industry.

  20. Lethal and sub-lethal effects of UVB on juvenile Biomphalaria glabrata (Mollusca: Pulmonata).

    Science.gov (United States)

    Ruelas, Debbie S; Karentz, Deneb; Sullivan, John T

    2006-11-01

    Although Schistosoma mansoni occurs mainly in the tropics, where intense levels of solar radiation are present, the impact of ultraviolet (UV) light on schistosome transmission is not known. The purpose of this study was to investigate potential effects of UVB (290-320nm) on juvenile Biomphalaria glabrata, the snail intermediate host of S. mansoni. Albino and wild-type snails were exposed to doses of UVB from UV-fluorescent lamps, and the following were measured: survival, photoreactivation (light-mediated DNA repair), effects on feeding behavior, and morphological tissue abnormalities. Irradiation with UVB is lethal to B. glabrata in a dose-dependent manner. Exposure to white light subsequent to UVB irradiation enhances survival, probably by photoreactivation. The shell offers some, but not complete, protection. Experiments in which UVB transmittance through the shell was blocked with black nail polish suggest that injury to both exposed (headfoot) and shell-enclosed (mantle and visceral mass) tissues contributes to mortality in lethally irradiated snails. Wild-type (pigmented) snails are less susceptible to lethal effects of UVB than albino snails, and they may be more capable of photoreactivation. UVB exposure inhibits snail feeding behavior, and causes tentacle forks and growths on the headfoot. Thus, UVB may influence the life cycle of S. mansoni by both lethal and sub-lethal damage to the snail intermediate host. However, the ability of snails to photoreactivate may mitigate these effects.

  1. Lethal and Sublethal Effects of Some Chemical and Biological Insecticides on Tuta absoluta (Lepidoptera: Gelechiidae) Eggs and Neonates.

    Science.gov (United States)

    Nozad-Bonab, Z; Hejazi, M J; Iranipour, Sh; Arzanlou, M

    2017-06-01

    Tuta absoluta (Meyrick) is one of the serious pests of tomatoes. This study was conducted to evaluate the effects of some chemical and biological insecticides on T. absoluta. The insecticides tested were diazinon, dichlorvos, chlorantraniliprole, deltamethrin, acetamiprid, imidacloprid, spinosad, abamectin, indoxacarb, Bacillus thuringiensis Berliner, Beauveria bassiana (Balsamo) Vuillemin, and Metarhizium anisopliae (Metschnikoff) Sorokin. Sublethal effects for the most effective insecticides tested, namely, abamectin, spinosad, chlorantraniliprole, and indoxacarb were assessed, and life table parameters were calculated. Chlorantraniliprole had the highest lethal effect on T. absoluta followed by spinosad, abamectin, and indoxacarb. On the other hand, imidacloprid was not considerably effective on T. absoluta eggs. Metarhizium anisopliae was 11 and 518 times more effective on the eggs and newly hatched larvae than B. bassiana and B. thuringiensis, respectively. Chlorantraniliprole, spinosad, abamectin, and indoxacarb affected life table parameters of T. absoluta significantly (α = 0.05). Spinosad had the highest sublethal effect on T. absoluta followed by abamectin, chlorantraniliprole, and indoxacarb. The results revealed that chlorantraniliprole, spinosad, abamectin, and indoxacarb had considerable lethal and sublethal effects on T. absoluta, and if they perform similarly in commercial greenhouses and fields, they would be suitable candidates to be considered in IPM programs for this pest. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Sublethal toxicity of commercial formulations of deltamethrin and permethrin on selected biochemical constituents and enzyme activities in liver and muscle tissues of Anabas testudineus.

    Science.gov (United States)

    Sapana Devi, Maisnam; Gupta, Abhik

    2014-10-01

    The freshwater fish Anabas testudineus was exposed for 21 days to two commercial formulations of synthetic pyrethroids deltamethrin and permethrin at sublethal concentrations of 0.007 and 0.0007 mg L(-1), and 0.093 and 0.0093 mg L(-1), that represented 10% and 1%, respectively, of the 96 h LC50 of these two pesticides for this fish. The glycogen, protein and lactic acid contents, along with succinate dehydrogenase (SDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) enzyme activities in liver and muscle tissues of control and pesticide-exposed fish were estimated. When compared with those of control fish, significant depletion of glycogen content was observed in liver, and that of protein in muscle tissue of fish treated with both the pesticides at their higher as well as lower concentrations. Lactic acid reduction was significant only in fish muscle treated with deltamethrin. SDH level was reduced significantly in both liver and muscle tissues except in fish exposed to 0.0093 mg L(-1) permethrin. AST level was reduced significantly in liver and muscle tissues and ALT in muscle tissue of deltamethrin treated fish only. It is concluded that deltamethrin, a type-II pyrethroid, is more toxic to fish than the type-I pyrethroid permethrin and is capable of rendering toxicity at a dose as low as 1% of its LC50 value. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Sublethal Effects of Neonicotinoid Insecticide on Calling Behavior and Pheromone Production of Tortricid Moths.

    Science.gov (United States)

    Navarro-Roldán, Miguel A; Gemeno, César

    2017-09-01

    In moths, sexual behavior combines female sex pheromone production and calling behavior. The normal functioning of these periodic events requires an intact nervous system. Neurotoxic insecticide residues in the agroecosystem could impact the normal functioning of pheromone communication through alteration of the nervous system. In this study we assess whether sublethal concentrations of the neonicotinoid insecticide thiacloprid, that competitively modulates nicotinic acetylcholine receptors at the dendrite, affect pheromone production and calling behavior in adults of three economically important tortricid moth pests; Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). Thiacloprid significantly reduced the amount of calling in C. pomonella females at LC 0.001 (a lethal concentration that kills only 1 in 10 5 individuals), and altered its calling period at LC 1 , and in both cases the effect was dose-dependent. In the other two species the effect was similar but started at higher LCs, and the effect was relatively small in L. botrana. Pheromone production was altered only in C. pomonella, with a reduction of the major compound, codlemone, and one minor component, starting at LC 10 . Since sex pheromones and neonicotinoids are used together in the management of these three species, our results could have implications regarding the interaction between these two pest control methods.

  4. Sublethal effects of petroleum fractions on the behavior of the lobster, Homarus americanus, and the mud snail, Nassarius obsoletus

    Energy Technology Data Exchange (ETDEWEB)

    Atema, J.

    1976-01-01

    Studies by our laboratory on sublethal effects of petroleum fractions on behavior of H. americanus and N. obsoletus are summarized in an attempt to clarify contradictory results and to gain an understanding of the underlying principles. There appear a surprising number of similarities in the way specific petroleum fractions affect the behavior of a crustacean arthropod and a gastropod mollusc. Acute toxicity, caused perhaps by the branched-cyclic fraction, was evident in short term exposures to whole No. 2 fuel oil at 50 ppM and kerosene in ..mu..l/100 l quantities. Feeding attraction, caused perhaps by the branched-cyclic fraction in lower concentrations, was seen after exposure to 1 ppM No. 2 fuel oil, and to kerosene and its branched-cyclic and polar-aromatic fractions in ..mu..l/100 l quantities. Repulsion and feeding inhibition, caused perhaps by the polar-aromatic fraction which contains most of the soluble materials, was observed in response to many concentrations of No. 2 fuel oil and kerosene, and their soluble fractions down to 1 ppB levels. No effect was apparent in exposures to the lower concentrations of solubles of .1 and .01 ppM No. 2 fuel oil and to solubles of La Rosa crude at 10 ppB. The hypothesis is advanced that specific hydrocarbon fractions in specific amounts are responsible for distinct behavioral changes; these fractions are present in varying quantities in different oils; and the changes in behavior are general enough to affect a large number of marine invertebrates in a similar manner.

  5. Haematological, blood biochemical and histopathological effects of sublethal cadmium and lead concentrations in common carp

    Directory of Open Access Journals (Sweden)

    M.K.Khalesi

    2017-06-01

    Full Text Available The present research aimed at examining the effects of common carp (Cyprinus carpio exposure to sublethal concentrations of two non-essential heavy metals: cadmium (Cd: 8.4 mg/L and lead (Pb: 6.2 mg/L for 15 days to evaluate occurring biochemical and haematological effects. The examined parameters included haematocrit (Hct, haemoglobin (Hb, lymphocytes (Lym, neutrophils (Neu, total protein (TP, albumin (Alb, immunoglobulin M (IgM, glucose, red and white blood cells counts (RBC & WBC, mean corpuscular volume (MCV, mean corpuscular haemoglobin (MCH, and mean corpuscular haemoglobin concentration (MCHC. Exposure to both metals significantly (P<0.05 reduced the amounts of WBC and MCHC. MCV values decreased (P<0.05 after the Pb treatment but MCV estimates with Cd exposure showed no differences. MCH levels increased in both treatments (P<0.05 whereas Hct, Hb, RBC, Lym, and Neu following both metal exposures were almost similar to those in the control. IgM values were elevated in fish contaminated with both Pb and Cd (P<0.05. The exposed fish showed fusion of gill lamellae, vessel dilatation, hyperaemia, and hyperplasia of gill epithelial cells whereas muscle histology remained unchanged. The observed responses can be secondary to low heavy metals concentrations reflecting the trigger of stress reactions in affected fish

  6. The sub-lethal effects of repeated freezing in the woolly bear caterpillar Pyrrharctia isabella.

    Science.gov (United States)

    Marshall, Katie E; Sinclair, Brent J

    2011-04-01

    Repeated freeze-thaw cycles are common and are increasing in frequency with climate change in many temperate locations, yet understanding of their impact on freeze-tolerant insects is extremely limited. We investigated the effects of repeated freezing and thawing on the freeze-tolerant final instar caterpillars of the moth Pyrrharctia isabella (Lepidoptera: Arctiidae) by subjecting individuals to either a single sustained 35 h freeze or five 7 h freezes. Sub-lethal effects were quantified with changes in three broad groups of measures: (1) cold hardiness, (2) metabolic rate and energy reserves and (3) survival after challenge with fungal spores. Repeated freeze-thaw cycles increased mortality to almost 30% and increased tissue damage in Malpighian tubules and hemocytes. Repeated freezing increased caterpillar glycerol concentration by 0.82 mol l(-1). There were no changes in metabolic rate or energy reserves with repeated freezing. For the first time, we report increased survival after immune challenge in caterpillars after freezing and suggest that this may be linked to wounding during freezing. We suggest that little repair of freezing damage is possible in P. isabella caterpillars and repeated freeze-thaw cycles may present significant challenges to survival in this species.

  7. Sublethal Effects of Spirodiclofen on Tetranychus urticae Koch_Pre-Ovipositional Females After Different Exposure Times

    Directory of Open Access Journals (Sweden)

    Dejan Marčić

    2006-01-01

    Full Text Available Sublethal effect of spirodiclofen on Tetranychus urticae females that survived different exposure times in the pre-ovipositional period was evaluated calculating two parameters - instantaneous rate of increase and net fertility - after six days of reproduction. The females were exposed to four concentrations/doses of the acaricide: 96 mg /L (0.24 μg/cm2, 48 mg/L(0.12 μg/cm2, 24 mg/L (0.06 μg/cm2 and 12 mg./L (0.03 μg/cm2 for 2, 6 and 24h in a leaf disc bioassay. After 24h exposure to 12 mg/L, instantaneous rate of increase was significantlyreduced (0.545; 0.634 in control, while significant reduction in net fertility (20.61; 28.57 in the control was recorded even after 2h exposure to the same concentration. The effect of all tested concentrations of spirodiclofen on both parameters increased with exposure time. The lowest values of instantaneous rate of increase (0.268 and net fertility (2.58 were recorded after 24h exposure to 96 mg/L. After 24h exposure, the concentration increase from 12 to 24 mg/L significantly reduced both parameters, while a further increase from 24 to 96 mg/L significantly reduced instantaneous rate of increase, but not net-fertility. The results regarding T. urticae population management are discussed.

  8. Sublethal Effects of the Neonicotinoid Insecticide Thiamethoxam on the Transcriptome of the Honey Bees (Hymenoptera: Apidae).

    Science.gov (United States)

    Shi, Teng-Fei; Wang, Yu-Fei; Liu, Fang; Qi, Lei; Yu, Lin-Sheng

    2017-12-05

    Neonicotinoid insecticides are now the most widely used insecticides in the world. Previous studies have indicated that sublethal doses of neonicotinoids impair learning, memory capacity, foraging, and immunocompetence in honey bees (Apis mellifera, Linnaeus) (Hymenoptera: Apidae). Despite these, few studies have been carried out on the molecular effects of neonicotinoids. In this study, we focus on the second-generation neonicotinoid thiamethoxam, which is currently widely used in agriculture to protect crops. Using high-throughput RNA-Seq, we investigated the transcriptome profile of honey bees after subchronic exposure to 10 ppb thiamethoxam over 10 d. In total, 609 differentially expressed genes (DEGs) were identified, of which 225 were upregulated and 384 were downregulated. Several genes, including vitellogenin, CSP3, defensin-1, Mrjp1, and Cyp6as5 were selected and further validated using real-time quantitative polymerase chain reaction assays. The functions of some DEGs were identified, and Gene Ontology-enrichment analysis showed that the enriched DEGs were mainly linked to metabolism, biosynthesis, and translation. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that thiamethoxam affected biological processes including ribosomes, the oxidative phosphorylation pathway, tyrosine metabolism pathway, pentose and glucuronate interconversions, and drug metabolism. Overall, our results provide a basis for understanding the molecular mechanisms of the complex interactions between neonicotinoid insecticides and honey bees. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Evaluation of Pyrethrin Formulations on Dengue/Dengue Haemorrhagic Fever Vectors in the Laboratory and Sublethal Effects

    Directory of Open Access Journals (Sweden)

    S Sulaiman

    2007-12-01

    Full Text Available In Southeast Asia, Aedes aegypti (L. has been incriminated as principal vector of dengue viruses and Ae. albopictus as the secondary vector of dengue fever. Therefore, the aim of this study was to investigate the effectiveness of three for-mula¬tions of pyrethrin derived from Tanacetum cinerariaefolium against the dengue/dengue haemorrhagic fever vectors Aedes aegypti and Ae. albopictus in the laboratory. The testings employed 2 methodologies: the WHO Larval Bioassay and WHO Adult Bioassay. The results showed that all the three pyrethrin formulations had larvicidal and adulticidal activi-ties. The impact of the sublethal doses of pyrethrin formulations on Aedes spp. larvae resulted in 4-6% of alive adult emergence compared to 90% of Ae. aegypti emerging adults and 96% Ae. albopictus alive adult emergence in the control. The impact of sublethal doses of the pyrethrin formulations caused very low fecundity on both Aedes spp. compared to the control (P< 0.05.

  10. Influence of UVB radiation on the lethal and sublethal toxicity of dispersed crude oil to planktonic copepod nauplii

    DEFF Research Database (Denmark)

    Almeda, Rodrigo; Harvey, Tracy E.; Connelly, Tara L

    2016-01-01

    in the sea after oil spills are highly toxic to copepod nauplii and that natural levels of UVB radiation substantially increase the toxicity of crude oil to these planktonic organisms. Overall, this study emphasizes the importance of considering sunlight in petroleum toxicological studies and models...... to naupliar stages of the planktonic copepods Acartia tonsa, Temora turbinata and Pseudodiaptomus pelagicus. Low concentrations of dispersed crude oil (1 μL L(-1)) caused a significant reduction in survival, growth and swimming activity of copepod nauplii after 48 h of exposure. UVB radiation increased...

  11. The Effect of Acclimation to Sublethal Temperature on Subsequent Susceptibility of Sitophilus zeamais Mostchulsky (Coleoptera: Curculionidae) to High Temperatures.

    Science.gov (United States)

    Lü, Jianhua; Zhang, Huina

    2016-01-01

    Heat treatment is a popular alternative to synthetic pesticides in disinfesting food-processing facilities and empty grain storages. Sitophilus zeamais Mostchulsky is one of the most cosmopolitan and destructive insects found in empty grain storage facilities and processing facilities. The effect of acclimation in S. zeamais adults to sublethal high temperature on their subsequent susceptibility to high temperatures was investigated. S. zeamais adults were acclimated to 36°C for 0 (as a control), 1, 3, and 5 h, and then were exposed at 43, 47, 51, and 55°C for different time intervals respectively. Acclimation to sublethal high temperature significantly reduced subsequent susceptibility of S. zeamais adults to lethal high temperatures of 43, 47, 51, and 55°C, although the mortality of S. zeamais adults significantly increased with increasing exposure time at lethal high temperatures. The mortality of S. zeamais adults with 1, 3, and 5 h of acclimation to 36°C was significantly lower than that of S. zeamais adults without acclimation when exposed to the same lethal high temperatures. The present results suggest that the whole facility should be heated to target lethal high temperature as soon as possible, avoiding decreasing the control effectiveness of heat treatment due to the acclimation in stored product insects to sublethal temperature.

  12. Lethal and Sublethal Effects of Insecticides Used on Citrus, on the Ectoparasitoid Tamarixia radiata.

    Science.gov (United States)

    Beloti, Vitor Hugo; Alves, Gustavo Rodrigues; Araújo, Diogo Feliciano Dias; Picoli, Mateus Manara; Moral, Rafael de Andrade; Demétrio, Clarice Garcia Borges; Yamamoto, Pedro Takao

    2015-01-01

    Huanglongbing (HLB) is a disease associated with the bacteria "Candidatus Liberibacter spp." and has been devastating citrus orchards around the world. Its management involves control of the insect vector, the Asian citrus psyllid Diaphorina citri Kuwayama. However, the indiscriminate use of chemicals has caused pest outbreaks and eliminated the natural enemies of the vector, such as the parasitoid Tamarixia radiata (Waterston), the main agent for biological control of D. citri. This study assessed the lethal and sublethal effects of insecticides recommended for integrated production of citrus on the parasitoid T. radiata. When adult parasitoids were exposed to residues of 25 insecticides, 20% of them, i.e., gamma-cyhalothrin, etofenprox, azadirachtin, tebufenozide and pyriproxyfen, were considered as harmless (Class 1), 12% as slightly harmful (Class 2), 12% as moderately harmful (Class 3) and 56% as harmful (Class 4), according to the classification proposed by the IOBC/WPRS. Afterward, 14 insecticides (5 harmless and 9 harmful) were sprayed on the parasitoid pupae. Of the 14 insecticides tested, only the organophosphates dimethoate and chlorpyrifos affected the parasitoid emergence. The effects of insecticides on the parasitism capacity of adults exposed to residues of azadirachtin, etofenprox, gamma-cyhalothrin, pyriproxyfen and tebufenozide (harmless) were also evaluated. Tebufenozide and gamma-cyhalothrin affected the parasitism of the F0 generation, but did not affect the emergence of the F1 and F2 generations. Therefore, for an effective IPM program, selective insecticides or harmful pesticides to adult parasitoids could be used in the field, provided that the adults do not occur naturally and the chemical applications do not coincide with parasitoid releases.

  13. Lethal and Sublethal Effects of Insecticides Used on Citrus, on the Ectoparasitoid Tamarixia radiata.

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    Vitor Hugo Beloti

    Full Text Available Huanglongbing (HLB is a disease associated with the bacteria "Candidatus Liberibacter spp." and has been devastating citrus orchards around the world. Its management involves control of the insect vector, the Asian citrus psyllid Diaphorina citri Kuwayama. However, the indiscriminate use of chemicals has caused pest outbreaks and eliminated the natural enemies of the vector, such as the parasitoid Tamarixia radiata (Waterston, the main agent for biological control of D. citri. This study assessed the lethal and sublethal effects of insecticides recommended for integrated production of citrus on the parasitoid T. radiata. When adult parasitoids were exposed to residues of 25 insecticides, 20% of them, i.e., gamma-cyhalothrin, etofenprox, azadirachtin, tebufenozide and pyriproxyfen, were considered as harmless (Class 1, 12% as slightly harmful (Class 2, 12% as moderately harmful (Class 3 and 56% as harmful (Class 4, according to the classification proposed by the IOBC/WPRS. Afterward, 14 insecticides (5 harmless and 9 harmful were sprayed on the parasitoid pupae. Of the 14 insecticides tested, only the organophosphates dimethoate and chlorpyrifos affected the parasitoid emergence. The effects of insecticides on the parasitism capacity of adults exposed to residues of azadirachtin, etofenprox, gamma-cyhalothrin, pyriproxyfen and tebufenozide (harmless were also evaluated. Tebufenozide and gamma-cyhalothrin affected the parasitism of the F0 generation, but did not affect the emergence of the F1 and F2 generations. Therefore, for an effective IPM program, selective insecticides or harmful pesticides to adult parasitoids could be used in the field, provided that the adults do not occur naturally and the chemical applications do not coincide with parasitoid releases.

  14. Toxic and hormetic-like effects of three components of citrus essential oils on adult Mediterranean fruit flies (Ceratitis capitata.

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    Stella A Papanastasiou

    Full Text Available Plant essential oils (EOs and a wide range of their individual components are involved in a variety of biological interactions with insect pests including stimulatory, deterrent, toxic and even hormetic effects. Both the beneficial and toxic properties of citrus EOs on the Mediterranean fruit fly (medfly have been experimentally evidenced over the last years. However, no information is available regarding the toxic or beneficial effects of the major components of citrus EOs via contact with the adults of the Mediterranean fruit fly. In the present study, we explored the toxicity of limonene, linalool and α-pinene (3 of the main compounds of citrus EOs against adult medflies and identified the effects of sub-lethal doses of limonene on fitness traits in a relaxed [full diet (yeast and sugar] and in a stressful (sugar only feeding environment. Our results demonstrate that all three compounds inferred high toxicity to adult medflies regardless of the diet, with males being more sensitive than females. Sub-lethal doses of limonene (LD20 enhanced the lifespan of adult medflies when they were deprived of protein. Fecundity was positively affected when females were exposed to limonene sub-lethal doses. Therefore, limonene, a major constituent of citrus EOs, induces high mortality at increased doses and positive effects on life history traits of medfly adults through contact at low sub-lethal doses. A hormetic-like effect of limonene to adult medflies and its possible underlying mechanisms are discussed.

  15. Assessment of chronic sublethal effects of imidacloprid on honey bee colony health.

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    Galen P Dively

    Full Text Available Here we present results of a three-year study to determine the fate of imidacloprid residues in hive matrices and to assess chronic sublethal effects on whole honey bee colonies fed supplemental pollen diet containing imidacloprid at 5, 20 and 100 μg/kg over multiple brood cycles. Various endpoints of colony performance and foraging behavior were measured during and after exposure, including winter survival. Imidacloprid residues became diluted or non-detectable within colonies due to the processing of beebread and honey and the rapid metabolism of the chemical. Imidacloprid exposure doses up to 100 μg/kg had no significant effects on foraging activity or other colony performance indicators during and shortly after exposure. Diseases and pest species did not affect colony health but infestations of Varroa mites were significantly higher in exposed colonies. Honey stores indicated that exposed colonies may have avoided the contaminated food. Imidacloprid dose effects was delayed later in the summer, when colonies exposed to 20 and 100 μg/kg experienced higher rates of queen failure and broodless periods, which led to weaker colonies going into the winter. Pooled over two years, winter survival of colonies averaged 85.7, 72.4, 61.2 and 59.2% in the control, 5, 20 and 100 μg/kg treatment groups, respectively. Analysis of colony survival data showed a significant dose effect, and all contrast tests comparing survival between control and treatment groups were significant, except for colonies exposed to 5 μg/kg. Given the weight of evidence, chronic exposure to imidacloprid at the higher range of field doses (20 to 100 μg/kg in pollen of certain treated crops could cause negative impacts on honey bee colony health and reduced overwintering success, but the most likely encountered high range of field doses relevant for seed-treated crops (5 μg/kg had negligible effects on colony health and are unlikely a sole cause of colony declines.

  16. Sublethal effect of nanosilver on the structure of gill of Caspian roach (Rutilus rutilus caspicus fingerlings

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    Maryam Sharifian

    2013-04-01

    Full Text Available Widespread use of nanosilver can be led the contamination of aquatic environment and impact on living organisms such as fishes. We investigated histopathological changes in the gills tissue of Caspian roach fingerlings after two weeks exposure to sublethal concentrations of nanosilver. Following one and two weeks exposure, necrosis, shortening of secondary lamellae, edema, destruction of epithelial lamella, shortening of secondary lamellae, epithelial lifting and curling of secondary lamellae were observed in gill tissues. This observation showed that exposure to sub-lethal concentrations of nanosilver is caused damages in the gill tissues of Caspian roach. The results demonstrated direct correlation of gill tissue damage and toxin exposure i.e. increasing nanosilver concentration is caused more tissue damage. Hence, histopathological changes of gill can considered as a proper indicator for nanosilver contamination of aquatic environments.

  17. Exposure to a sublethal concentration of imidacloprid and the side effects on target and nontarget organs of Apis mellifera (Hymenoptera, Apidae).

    Science.gov (United States)

    Catae, Aline Fernanda; Roat, Thaisa Cristina; Pratavieira, Marcel; Silva Menegasso, Anally Ribeiro da; Palma, Mario Sergio; Malaspina, Osmar

    2018-03-01

    The use of insecticides has become increasingly frequent, and studies indicate that these compounds are involved in the intoxication of bees. Imidacloprid is a widely used neonicotinoid; thus, we have highlighted the importance of assessing its oral toxicity to Africanized bees and used transmission electron microscopy to investigate the sublethal effects in the brain, the target organ, and the midgut, responsible for the digestion/absorption of food. In addition, the distribution of proteins involved in important biological processes in the brain were evaluated on the 1st day of exposure by MALDI-imaging analysis. Bioassays were performed to determine the Median Lethal Concentration (LC 50 ) of imidacloprid to bees, and the value obtained was 1.4651 ng imidacloprid/μL diet. Based on this result, the sublethal concentration to be administered at 1, 4 and 8 days was established as a hundredth (1/100) of the LC 50 . The results obtained from the ultrastructural analysis showed alterations in the midgut cells of bees as nuclear and mitochondrial damage and an increase of vacuoles. The insecticide caused spacing among the Kenyon cells in the mushroom bodies, chromatin condensation and loss of mitochondrial cristae. The MALDI-imaging analysis showed an increase in the expression of such proteins as vascular endothelial growth factor receptor, amyloid protein precursor and protein kinase C, which are related to oxygen supply, neuronal degeneration and memory/learning, and a decrease in the expression of the nicotinic acetylcholine receptor alpha 1, which is fundamental to the synapses. These alterations demonstrated that imidacloprid could compromise the viability of the midgut epithelium, as well as inhibiting important cognitive processes in individuals, and may be reflected in losses of the colony.

  18. The sensitive hare: sublethal effects of predator stress on reproduction in snowshoe hares.

    Science.gov (United States)

    Sheriff, Michael J; Krebs, Charles J; Boonstra, Rudy

    2009-11-01

    1. Prey responses to high predation risk can be morphological or behavioural and ultimately come at the cost of survival, growth, body condition, or reproduction. These sub-lethal predator effects have been shown to be mediated by physiological stress. We tested the hypothesis that elevated glucocorticoid concentrations directly cause a decline in reproduction in individual free-ranging female snowshoe hares, Lepus americanus. We measured the cortisol concentration from each dam (using a faecal analysis enzyme immunoassay) and her reproductive output (litter size, offspring birth mass, offspring right hind foot (RHF) length) 30 h after birth. 2. In a natural monitoring study, we monitored hares during the first and second litter from the population peak (2006) to the second year of the decline (2008). We found that faecal cortisol metabolite (FCM) concentration in dams decreased 52% from the first to the second litter. From the first to the second litter, litter size increased 122%, offspring body mass increased 130%, and offspring RHF length increased 112%. Dam FCM concentrations were inversely related to litter size (r(2) = 0.19), to offspring birth mass (r(2) = 0.32), and to offspring RHF length (r(2) = 0.64). 3. In an experimental manipulation, we assigned wild-caught, pregnant hares to a control and a stressed group and held them in pens. Hares in the stressed group were exposed to a dog 1-2 min every other day before parturition to simulate high predation risk. At parturition, unsuccessful-stressed dams (those that failed to give birth to live young) and stressed dams had 837% and 214%, respectively, higher FCM concentrations than control dams. Of those females that gave birth, litter size was similar between control and stressed dams. However, offspring from stressed dams were 37% lighter and 16% smaller than offspring from control dams. Increasing FCM concentration in dams caused the decline of offspring body mass (r(2) = 0.57) and RHF (r(2) = 0.52). 4

  19. Effect of sub-lethal exposure to ultraviolet radiation on the escape performance of Atlantic cod larvae (Gadus morhua.

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    Yuichi Fukunishi

    Full Text Available The amount of ultraviolet (UV radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments: two-spotted goby (Gobiusculus flavescens; a suction predator and lion's mane jellyfish (Cyanea capillata; a "passive" ambush predator. Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100, escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively were significantly lower than those of control larvae (75%, 69±4.7 mm respectively. There was a significant difference in survival as well (UV: 35%,63%. No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%,74% in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations.

  20. Protective effect of a laser-induced sub-lethal temperature rise on RPE cells from oxidative stress.

    Science.gov (United States)

    Iwami, Hisashi; Pruessner, Joachim; Shiraki, Kunihiko; Brinkmann, Ralf; Miura, Yoko

    2014-07-01

    Recently introduced new technologies that enable temperature-controlled laser irradiation on the RPE allowed us to investigate temperature-resolved RPE cell responses. In this study we aimed primarily to establish an experimental setup that can realize laser irradiation on RPE cell culture with the similar temperature distribution as in the clinical application, with a precise time/temperature history. With this setup, we conducted investigations to elucidate the temperature-dependent RPE cell biochemical responses and the effect of transient hyperthermia on the responses of RPE cells to the secondary-exposed oxidative stress. Porcine RPE cells cultivated in a culture dish (inner diameter = 30 mm) with culture medium were used, on which laser radiation (λ = 1940 nm, spot diameter = 30 mm) over 10 s was applied as a heat source. The irradiation provides a radially decreasing temperature profile which is close to a Gaussian shape with the highest temperature in the center. Power setting for irradiation was determined such that the peak temperature (Tmax) in the center of the laser spot at the cells reaches from 40 °C to 58 °C (40, 43, 46, 50, 58 °C). Cell viability was investigated with ethidium homodimer III staining at the time points of 3 and 24 h following laser irradiation. Twenty four hours after laser irradiation the cells were exposed to hydrogen peroxide (H2O2) for 5 h, followed by the measurement of intracellular glutathione, intracellular 4-hydroxynonenal (HNE) protein adducts, and secreted vascular endothelial growth factor (VEGF). The mean temperature threshold for RPE cell death after 3 h was found to be around 52 °C, and for 24 h around 50 °C with the current irradiation setting. A sub-lethal preconditioning on Tmax = 43 °C significantly induced the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio, and decreased H2O2-induced increase of intracellular 4-HNE protein adducts. Although sub-lethal hyperthermia (Tmax

  1. Sublethal effect of pyriproxyfen released from a fumigant formulation on fecundity, fertility, and ovicidal action in Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Harburguer, Laura; Zerba, Eduardo; Licastro, Susana

    2014-03-01

    Dengue and dengue hemorrhagic fever are mosquito-borne viral diseases that coincide with the distribution of Aedes aegypti (L.), the primary vector in the tropical and semitropical world. With no available vaccine, controlling the dengue vector is essential to prevent epidemics. The effects of the insect growth regulator pyriproxyfen on Ae. aegypti adults that survived a treatment with a sublethal dose were investigated in the laboratory, including effects on their reproductive potential. Pyriproxyfen was released from a fumigant formulation at a dose causing 20 or 40% emergence inhibition (%EI). Females were dissected before and after blood feeding and the basal follicle number was counted. There were no differences between the control and treated group on the basal follicle number for both doses used. Fertility and fecundity were reduced at a concentration of EI40 but no at EI20. There was no ovicidal effect of pyriproxyfen by immersion of eggs in treated water neither when the females laid their eggs on a pyriproxyfen-treated surface. This work shows that sublethal doses of pyriproxyfen can have effects on fertility and fecundity ofAe. aegypti females, which together with its larvicidal activity could contribute to an overall decrease in a given population.

  2. Sublethal Toxicity of Crude Oil Exposure in The Blue Crab, Callinectes sapidus, at Two Life History Stages.

    Science.gov (United States)

    Giltz, Sarah M; Taylor, Caz M

    2017-02-01

    The 2010 Deepwater Horizon oil spill occurred during peak spawning season for many Gulf of Mexico fish and invertebrates. Early life stages of important fishery species were at risk to encounter crude oil. In this study, we investigated the effect of crude oil exposure on two life stages of the blue crab (Callinectes sapidus). We tested the effects of oil exposure on the survival and growth of larval (pelagic) and juvenile (estuarine) blue crabs as well as the effects of oil on the molt frequency of juveniles. Larval crabs exposed to crude oil showed no discernable growth or mortality differences when compared to non-exposed controls. Juvenile crabs exposed to oil also showed no differences in size but exhibited increased intermolt duration (time between molts). Our study suggests that different life-stages may respond differently when exposed to crude oil and that oil exposure negatively affects growth rate of juvenile blue crabs.

  3. Effects of sublethal copper exposure on two gammarid species: which is the best competitor?

    Science.gov (United States)

    Sroda, Sophie; Cossu-Leguille, Carole

    2011-01-01

    Biomarker responses in organisms exposed to copper were examined by comparing two gammarid species, Gammarus roeseli and Dikerogammarus villosus, based on gender. G. roeseli specimens were exposed to 20 μg/L of copper for 6, 12, 24 and 48-h periods, while D. villosus were exposed to 20 and 30 μg/L of copper for 12, 48 and 72 h. Males and females of each species were exposed separately and biomarker measurements were performed for each species and gender. The selected biomarkers were antioxidant enzymes as total glutathione peroxidase (GPxtot), selenium-dependent glutathione peroxidase (SeGPx), and catalase activities. Malondialdehyde level (MDA) was measured as a biomarker of toxic effect. Energy reserves were evaluated by means of lipid, glycogen and protein levels. For both species and gender, antioxidant enzyme activities were weakly modified by copper exposure and differences were transient. MDA levels were increased in both species and genders in exposed animals compared to controls, when energy reserves were decreased. G. roeseli was more rapidly overwhelmed by copper toxicity while the first response of D. villosus was the mobilization of its energetic content. D. Villosus probably has specific physiological properties that enable it to cope with copper toxicity and thus become the best competitor.

  4. Sublethal effects of imidacloprid on the whitefly parasitoid Encarsia formosa Gahan

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    Drobnjaković Tanja

    2017-01-01

    Full Text Available Acute toxicity of an imidacloprid-based product (Confidor 200 SL to pupae of the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae, and its effects on life history traits and population growth in F1 generation of the surviving parasitoid females of a commercial strain ('Dutch' strain, D and two local populations from Serbia (Bujanovac, B; Negotin, N were examined in laboratory bioassays. All trials were carried out at 27±1°C temperature and 60±10% relative humidity, and under 16/8 h daylight/darkness photoperiod in four replications. In acute toxicity bioassays, tobacco leaves carrying parasitoid pupae were treated with a series of symmetrical concentrations (800, 400, 200, 100, 50 and 25 mg a.i./l covering a 10-90% mortality range. The product based on imidacloprid, applied directly onto parasitoid pupae at mean lethal concentrations (LC50 determined in the acute toxicity assays (30 mg/l, 20 mg/l and 25 mg/l, for populations B, N and D, respectively, significantly affected the survival of females developed from the treated pupae, extended the duration of juvenile development (by 1.81, 1.59 and 1.73 days for populations B, N and D, respectively, significantly reduced total parasitism of females D (25.92 %, total female adult emergence in populations B (27.48 % and D (17.92 %, and significantly reduced the instantaneous rate of increased only of females N (4.23 %. Considering the high acute toxicity of the imidacloprid product to the pupal stage of E. formosa, and significant reductions in life table and population parameters, imidacloprid is not considered compatible for simultaneous use with the parasitoid E. formosa. A more precise assessment of risks involved in the use of that insecticide requires a more detailed testing in the field. The implications of these results for the concept of integrated control of the greenhouse whitefly are discussed.

  5. A method for assessing sublethal effects of contaminants in soils to the earthworm, Eisenia foetida

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, M.H. [Univ. of Tennessee, Knoxville, TN (United States). Center for Environmental Biotechnology; Wicker, L.F.; Stewart, A.J. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.

    1996-03-01

    The authors developed and tested a procedure that allows quantification of the effects of soil contaminants on earthworm (Eisenia foetida) growth and reproduction. The procedure monitors isolated pairs of earthworms and generates a higher ratio of data per organisms than other commonly used procedures. It also incorporates an accurate technique for measuring adult growth, has high sensitivity compared to the Organization for Economic Cooperation and Development (OECD) 14-d acute toxicity test, and is cost effective. The authors applied the method to a variety of soil-testing problems. A food-and-substrate trial using artificial soil demonstrated the sensitivity of the method and the need for food supplementation to stimulate earthworm reproduction. Application of the procedure to assess efficacy of a soil bioremediation technology revealed the advantage of measuring both growth and reproduction and highlighted the usefulness of a single integrated measure of these two responses. The method also was used as a fast-screening analysis for field soils in a large-scale ecological risk assessment. Finally, a reference toxicant, used in dilution series, demonstrated that responses of E. foetida using the authors` method were similar to their responses in the OECD artificial-soil test method. The results of this study indicate that this procedure can be used both for regulatory and compliance needs within the framework of ecological risk assessment.

  6. Exploring sub-lethal effects of exposure to a nucleopolyhedrovirus in the speckled wood (Pararge aegeria) butterfly.

    Science.gov (United States)

    Hesketh, Helen; Gibbs, Melanie; Breuker, Casper J; Van Dyck, Hans; Turner, Emma; Hails, Rosemary S

    2012-01-01

    This study investigated the sub-lethal effects of larval exposure to baculovirus on host life history and wing morphological traits using a model system, the speckled wood butterfly Pararge aegeria (L.) and the virus Autographa californica nucleopolyhedrovirus. Males and females showed similar responses to the viral infection. Infection significantly reduced larval growth rate, whilst an increase in development time allowed the critical mass for pupation to be attained. There was no direct effect of viral infection on the wing morphological traits examined. There was, however, an indirect effect of resisting infection; larvae that took longer to develop had reduced resource investment in adult flight muscle mass. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  7. Sub-lethal effects of pesticide residues in brood comb on worker honey bee (Apis mellifera development and longevity.

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    Judy Y Wu

    Full Text Available BACKGROUND: Numerous surveys reveal high levels of pesticide residue contamination in honey bee comb. We conducted studies to examine possible direct and indirect effects of pesticide exposure from contaminated brood comb on developing worker bees and adult worker lifespan. METHODOLOGY/PRINCIPAL FINDINGS: Worker bees were reared in brood comb containing high levels of known pesticide residues (treatment or in relatively uncontaminated brood comb (control. Delayed development was observed in bees reared in treatment combs containing high levels of pesticides particularly in the early stages (day 4 and 8 of worker bee development. Adult longevity was reduced by 4 days in bees exposed to pesticide residues in contaminated brood comb during development. Pesticide residue migration from comb containing high pesticide residues caused contamination of control comb after multiple brood cycles and provided insight on how quickly residues move through wax. Higher brood mortality and delayed adult emergence occurred after multiple brood cycles in contaminated control combs. In contrast, survivability increased in bees reared in treatment comb after multiple brood cycles when pesticide residues had been reduced in treatment combs due to residue migration into uncontaminated control combs, supporting comb replacement efforts. Chemical analysis after the experiment confirmed the migration of pesticide residues from treatment combs into previously uncontaminated control comb. CONCLUSIONS/SIGNIFICANCE: This study is the first to demonstrate sub-lethal effects on worker honey bees from pesticide residue exposure from contaminated brood comb. Sub-lethal effects, including delayed larval development and adult emergence or shortened adult longevity, can have indirect effects on the colony such as premature shifts in hive roles and foraging activity. In addition, longer development time for bees may provide a reproductive advantage for parasitic Varroa destructor

  8. Lethal and sublethal effects of pesticides on Chrysoperla carnea larvae (Neuroptera: Chrysopidae) and the influence of rainfastness in their degradation pattern over time.

    Science.gov (United States)

    Maia, Jader Braga; Carvalho, Geraldo Andrade; Medina, Pilar; Garzón, Agustín; Gontijo, Pablo da Costa; Viñuela, Elisa

    2016-07-01

    The predator Chrysoperla carnea is a model species for the study of non-target effects of pesticides under different scenarios: registration of plant protection products under the European Union and effects of the Bt toxin. Laboratory and persistence studies were carried out with six pesticides currently used in corn crops in Spain that were applied at their maximum field recommended concentrations. The assessed end-points were larval mortality, survivorship until adult stage, duration of the larval and pupal periods, fecundity, fertility and sex ratio of the emerged adults. Based on the total effect (lethal and sublethal) caused to L3 larvae in contact with fresh residues in the laboratory, pendimethalin was harmless (IOBC 1), lambda-cyhalothrin, abamectin, and hexythiazox were slightly harmful (IOBC 2), deltamethrin was moderately harmful (IOBC 3) and chlorpyrifos was harmful (IOBC 4). Afterwards, the residues of the two most toxic pesticides in the lab (deltamethrin and chlorpyrifos) were aged under greenhouse conditions (22 ± 2 °C, 40 ± 10 % R.H., 16.9 μmol m(-2) s(-1) UV radiation) in the presence and absence of artificial rainfall (10 l m(-2) h(-1), applied 24 h after pesticide application). Deltamethrin was classified as short lived (IOBC A) in both cases. However, degradation of chlorpyrifos residues was accelerated in the presence of rainfall, leading to the classification as slightly persistent (IOBC B), while in absence of rainfall it behaved as persistent (IOBC D). Every pesticide can be recommended for inclusion in corn IPM programs where the predator is present except chlorpyrifos that exhibited high direct toxicity in the lab and prolonged residual action even in the presence of rainfall.

  9. Experimental assessment of the effects of sublethal salinities on growth performance and stress in cultured tra catfish (Pangasianodon hypophthalmus).

    Science.gov (United States)

    Nguyen, Phuc Trong Hong; Do, Huong Thi Thanh; Mather, Peter B; Hurwood, David A

    2014-12-01

    The effects of a range of different sublethal salinities were assessed on physiological processes and growth performance in the freshwater 'tra' catfish (Pangasianodon hypophthalmus) juveniles over an 8-week experiment. Fish were distributed randomly among 6 salinity treatments [2, 6, 10, 14 and 18 g/L of salinity and a control (0 g/L)] with a subsequent 13-day period of acclimation. Low salinity conditions from 2 to 10 g/L provided optimal conditions with high survival and good growth performance, while 0 g/L and salinities >14 g/L gave poorer survival rates (p Tra catfish do not appear to be efficient osmoregulators when salinity levels exceed 10 g/L, and at raised salinity levels, growth performance is compromised. In general, results of this study confirm that providing culture environments in the Mekong River Basin do not exceed 10 g/L salinity and that cultured tra catfish can continue to perform well.

  10. Assessment of acute sublethal effects of clothianidin on motor function of honeybee workers using video-tracking analysis.

    Science.gov (United States)

    Alkassab, Abdulrahim T; Kirchner, Wolfgang H

    2018-01-01

    Sublethal impacts of pesticides on the locomotor activity might occur to different degrees and could escape visual observation. Therefore, our objective is the utilization of video-tracking to quantify how the acute oral exposure to different doses (0.1-2ng/bee) of the neonicotinoid "clothianidin" influences the locomotor activity of honeybees in a time course experiment. The total distance moved, resting time as well as the duration and frequency of bouts of laying upside down are measured. Our results show that bees exposed to acute sublethal doses of clothianidin exhibit a significant increase in the total distance moved after 30 and 60min of the treatment at the highest dose (2ng/bee). Nevertheless, a reduction of the total distance is observed at this dose 90min post-treatment compared to the distance of the same group after 30min, where the treated bees show an arched abdomen and start to lose their postural control. The treated bees with 1ng clothianidin show a significant increase in total distance moved over the experimental period. Moreover, a reduction in the resting time and increase of the duration and frequency of bouts of laying upside down at these doses are found. Furthermore, significant effects on the tested parameters are observed at the dose (0.5ng/bee) first at 60min post-treatment compared to untreated bees. The lowest dose (0.1ng/bee) has non-significant effects on the motor activity of honeybees compared to untreated bees over the experimental period. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Extended hypoxia in the alfalfa leafcutting bee, Megachile rotundata, increases survival but causes sub-lethal effects.

    Science.gov (United States)

    Abdelrahman, H; Rinehart, J P; Yocum, G D; Greenlee, K J; Helm, B R; Kemp, W P; Schulz, C H; Bowsher, J H

    2014-05-01

    Many insects are tolerant of hypoxic conditions, but survival may come at a cost to long-term health. The alfalfa leaf-cutting bee, Megachile rotundata, develops in brood cells inside natural cavities, and may be exposed to hypoxic conditions for extended periods of time. Whether M. rotundata is tolerant of hypoxia, and whether exposure results in sub-lethal effects, has never been investigated. Overwintering M. rotundata prepupae were exposed to 10%, 13%, 17%, 21% and 24% O2 for 11 months. Once adults emerged, five indicators of quality - emergence weight, body size, feeding activity, flight performance, and adult longevity, - were measured to determine whether adult bees that survived past exposure to hypoxia were competent pollinators. M. rotundata prepupae are tolerant of hypoxic condition and have higher survival rates in hypoxia, than in normoxia. Under hypoxia, adult emergence rates did not decrease over the 11 months of the experiment. In contrast, bees reared in normoxia had decreased emergence rates by 8 months, and were dead by 11 months. M. rotundata prepupae exposed to extended hypoxic conditions had similar emergence weight, head width, and cross-thorax distance compared to bees reared in standard 21% oxygen. Despite no significant morphological differences, hypoxia-exposed bees had lower feeding rates and shorter adult lifespans. Hypoxia may play a role in post-diapause physiology of M. rotundata, with prepupae showing better survival under hypoxic conditions. Extended exposure to hypoxia, while not fatal, causes sub-lethal effects in feeding rates and longevity in the adults, indicating that hypoxia tolerance comes at a cost. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. The effect of sublethal concentrations of the water-soluble fraction of crude oil on the chemosensory function of Caspian roach, Rutilus caspicus (YAKOVLEV, 1870).

    Science.gov (United States)

    Lari, Ebrahim; Abtahi, Behrooz; Hashtroudi, Mehri Seyed; Mohaddes, Effat; Døving, Kjell B

    2015-08-01

    The water-soluble fraction of crude oil is a complex and toxic mixture of hydrocarbons. Because aquatic organisms directly encounter it, the water-soluble fraction plays an important role in the toxicity of crude oil in aquatic environments. To determine whether fish are attracted to or avoid the water-soluble fraction, Caspian roaches (Rutilus caspicus) were exposed to different concentrations of the water-soluble fraction in a choice maze apparatus. The results showed that Caspian roaches can detect and avoid 2 mg/L of the water-soluble fraction. To study the effect of the water-soluble fraction on the olfactory function of fish, Caspian roaches were exposed to 3.2 mg/L and 16 mg/L of the water-soluble fraction for 96 h; afterward, exposed fish encountered food extract in a choice maze apparatus. The present study showed that the water-soluble fraction significantly impairs the olfactory function of roaches. To investigate the effect of olfactory system dysfunction on the feeding behavior of fish, Caspian roaches were exposed to 3.2 mg/L and 16 mg/L of the water-soluble fraction. After 4 d, 8 d, and 12 d of exposure, the feeding behavior toward the food extract was tested. The results showed that both 3.2 mg/L and 16 mg/L of the water-soluble fraction suppress the feeding behavior of Caspian roaches. The present study demonstrates that sublethal concentrations of crude oil's water-soluble fraction impair the olfactory function of fish and consequently suppress the feeding behavior. © 2015 SETAC.

  13. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum.

    Science.gov (United States)

    Amaradasa, B Sajeewa; Everhart, Sydney E

    2016-01-01

    Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor), iprodione (unclear mode of action), thiophanate methyl (inhibition of microtubulin synthesis) and azoxystrobin and pyraclostrobin (quinone outside inhibitors). Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50-100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR) loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs). SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each). Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed) generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA) and discriminant analysis of principal components (DAPC) identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001). Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the experiment, and

  14. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum.

    Directory of Open Access Journals (Sweden)

    B Sajeewa Amaradasa

    Full Text Available Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor, iprodione (unclear mode of action, thiophanate methyl (inhibition of microtubulin synthesis and azoxystrobin and pyraclostrobin (quinone outside inhibitors. Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50-100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs. SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each. Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA and discriminant analysis of principal components (DAPC identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001. Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the

  15. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum

    Science.gov (United States)

    Amaradasa, B. Sajeewa

    2016-01-01

    Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor), iprodione (unclear mode of action), thiophanate methyl (inhibition of microtubulin synthesis) and azoxystrobin and pyraclostrobin (quinone outside inhibitors). Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50–100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR) loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs). SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each). Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed) generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA) and discriminant analysis of principal components (DAPC) identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001). Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the experiment

  16. Sublethal Effects of Cyantraniliprole and Imidacloprid on Feeding Behavior and Life Table Parameters of Myzus persicae (Hemiptera: Aphididae).

    Science.gov (United States)

    Zeng, Xianyi; He, Yingqin; Wu, Jiaxing; Tang, Yuanman; Gu, Jitao; Ding, Wei; Zhang, Yongqiang

    2016-08-01

    The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), is an agricultural pest that seriously infests many crops worldwide. This study used electrical penetration graphs (EPGs) and life table parameters to estimate the sublethal effects of cyantraniliprole and imidacloprid on the feeding behavior and hormesis of M. persicae The sublethal concentrations (LC30) of cyantraniliprole and imidacloprid against adult M. persicae were 4.933 and 0.541 mg L(-1), respectively. The feeding data obtained from EPG analysis indicated that the count probes and number of short probes (<3 min) were significantly increased when aphids were exposed to LC30 of imidacloprid-treated plants. In addition, the phloem-feeding behavior of M persicae was significantly impaired on fed tobacco plants treated with cyantraniliprole and imidacloprid at LC30 Analysis of life table parameters indicated that the growth and reproduction of F1 generation aphids were significantly affected when initial adults were exposed to LC30 of cyantraniliprole and imidacloprid. The nymphal period, female longevity, total preoviposition period, and mean generation time were significantly prolonged when initial adults were exposed to LC30 of imidacloprid. By comparison, these parameters were prolonged but not significantly in the cyantraniliprole treatment. The fecundity and gross reproductive rate were significantly increased in the treated groups. Similarly, the net reproductive rate was greater in the treated group than the control group. Our results indicate that treatment with LC30 of imidacloprid and cyantraniliprole would lead to a hormetic response of M. persicae, with higher likelihood of occurrence when initial adults were exposed to LC30 of cyantraniliprole. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Sublethal effects of chlorantraniliprole on development, reproduction and vitellogenin gene (CsVg) expression in the rice stem borer, Chilo suppressalis.

    Science.gov (United States)

    Huang, Li; Lu, Mingxing; Han, Guangjie; Du, Yuzhou; Wang, Jianjun

    2016-12-01

    The rice stem borer, Chilo suppressalis (Walker), is one of the most damaging rice pests in the world. The sublethal effects of chlorantraniliprole on development,reproduction and mRNA expression levels of vitellogenin gene (CsVg) in C. suppressalis were investigated. Exposure of third-instar larvae to sublethal concentrations of chlorantraniliprole (LC10 and LC30 ) significantly extended larval duration, lowered the mean weight of male pupae and shortened male adult longevity. Pupal duration was significantly prolonged and the mean weight of female pupae was significantly lowered in the LC30 treatment group. While there were no significant sublethal effects on either the adult emergence rate or the egg hatch, the pupation rates in the LC10 treatment group (41.30%) and in the LC30 treatment group (23.98%) were significantly lower than the pupation rate of the control (71.86%), and LC10 and LC30 chlorantraniliprole significantly reduced fecundity, by 32.18 and 52.94% respectively. Furthermore, the expression levels of CsVg mRNA after exposure to LC10 and LC30 chlorantraniliprole significantly decreased, by 42.52 and 47.84% respectively, in 12-h-old female adults. Sublethal concentrations of chlorantraniliprole adversely affect the development and reproduction of C. suppressalis. The downregulation of CsVg by chlorantraniliprole might have negative impacts on the fecundity of C. suppressalis. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  18. Effect of sublethal lead exposure on gastric motility of red-tailed hawks.

    Science.gov (United States)

    Lawler, E M; Duke, G E; Redig, P T

    1991-07-01

    In order to determine the effects of low level lead exposure on gastric motility in raptors, strain gage transducers were surgically implanted on the serosal surface of the muscular stomach of three red-tailed hawks. The frequency and amplitude of gastric contractions during ingestion and early digestion were monitored for 1 week under control conditions and for 3 weeks while the birds were fed 0.82 or 1.64 mg lead (as lead acetate) per kg body weight each day. Exposure to these doses did not appreciably affect either the frequency or amplitude of gastric contractions in these birds. This low level lead exposure also had no consistent effect on the regular egestion of pellets of undigested material by hawks. Daily exposure to doses up to 6.55 mg lead/kg body weight did not affect the frequency or timing of pellet egestion, and exposure to 1.64 mg lead/kg did not affect the gastric contractions associated with pellet egestion. Although gastrointestinal dysfunction is often associated with clinical cases of acute lead toxicity, chronic exposure to these low levels of lead acetate did not significantly alter gastric motility in red-tailed hawks.

  19. A better method for assessing sublethal effects of soils to the earthworm Eisenia foetida

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, M.H. [Univ. of Tennessee, Knoxville, TN (United States); Wicker, L.F.; Stewart, A.J. [Oak Ridge National Lab., TN (United States)

    1994-12-31

    The authors have developed and tested a procedure which allows quantification of growth and reproductive effects of contaminated soils to the earthworm, Eisenia foetida. The procedure monitors isolated pairs of earthworms and generates a higher ratio of data per organism than other commonly used procedures which require larger numbers of earthworms per experimental unit. The procedure also incorporates an accurate technique for measuring adult growth. The method has high sensitivity and is cost-effective. The method was applied to a variety of soil-testing problems to demonstrate its versatility and provide validation. A food-and-substrate trial demonstrated the sensitivity of the method and the need for food supplementation in OECD artificial soil to stimulate earthworm reproduction. A trial to examine a soil bioremediation technology revealed the advantage of measuring both growth and reproduction and highlighted the usefulness of a single integrated measure of these two responses. The method then was applied as a fast-screening method for field soils in a large-scale ecological risk assessment. Finally, a reference toxicant, applied in dilution series, demonstrated that responses of Eisenia foetida to their method are similar to their responses to the OECD artificial soil test. Collectively, results of this study indicate that their procedure can be used both for regulatory and compliance needs within the framework of ecological risk assessment.

  20. Lethal and sublethal effects, and incomplete clearance of ingested imidacloprid in honey bees (Apis mellifera).

    Science.gov (United States)

    Sánchez-Bayo, Francisco; Belzunces, Luc; Bonmatin, Jean-Marc

    2017-08-22

    A previous study claimed a differential behavioural resilience between spring or summer honey bees (Apis mellifera) and bumble bees (Bombus terrestris) after exposure to syrup contaminated with 125 µg L(-1) imidacloprid for 8 days. The authors of that study based their assertion on the lack of body residues and toxic effects in honey bees, whereas bumble bees showed body residues of imidacloprid and impaired locomotion during the exposure. We have reproduced their experiment using winter honey bees subject to the same protocol. After exposure to syrup contaminated with 125 µg L(-1) imidacloprid, honey bees experienced high mortality rates (up to 45%), had body residues of imidacloprid in the range 2.7-5.7 ng g(-1) and exhibited abnormal behaviours (restless, apathetic, trembling and falling over) that were significantly different from the controls. There was incomplete clearance of the insecticide during the 10-day exposure period. Our results contrast with the findings reported in the previous study for spring or summer honey bees, but are consistent with the results reported for the other bee species.

  1. Sublethal effects of pyrethroid and neonicotinoid insecticides on Iphiseiodes zuluagai Denmark and Muma (Mesostigmata: Phytoseiidae).

    Science.gov (United States)

    Zanuzo Zanardi, Odimar; Pavan Bordini, Gabriela; Aparecida Franco, Aline; Jacob, Cynthia Renata Oliveira; Takao Yamamoto, Pedro

    2017-11-01

    The predator mite Iphiseiodes zuluagai Denmark & Muma is an important biological-control agent of mite pests, and it is one of the most common species found in citrus orchards. This study assessed, under laboratory conditions, the toxicity and duration of the harmful effects of five insecticides, the three pyrethroids deltamethrin, esfenvalerate and lambda-cyhalothrin, and the two neonicotinoids imidacloprid and thiamethoxam on I. zuluagai. Furthermore, we estimated the life-table parameters of the predator. Our results showed that deltamethrin and lambda-cyhalothrin caused higher mortality of larvae and adults than imidacloprid and thiamethoxam. In contrast, esfenvalerate provided larval mortality similar to imidacloprid and thiamethoxam, but it did not cause significant adult mortality of the predator. Mites that developed on pyrethroid residues showed lower survival of the immature stages, fecundity, and longevity compared to neonicotinoid residues and the control treatment. The estimated life-table parameters indicated that deltamethrin, lambda-cyhalothrin and esfenvalerate caused greater reduction in R o and r of I. zuluagai compared with imidacloprid and thiamethoxam, which were similar to the control treatment. Besides the impacts on biological and population parameters, the duration of the harmful activity of pyrethroid insecticides was longer than the neonicotinoids. Therefore, the use of pyrethroid insecticides to control pest insects may involve serious implications for integrated pest-management programs that aim to exploit the biological control by I. zuluagai in citrus orchards.

  2. Lethal and sublethal effects of the sediment-associated PCB Aroclor 1254 on a meiobenthic copepod

    Energy Technology Data Exchange (ETDEWEB)

    DiPinto, L.M.; Coull, B.C.; Chandler, G.T. (Univ. of South Carolina, Columbia, SC (United States). Dept. of Environmental Health Sciences, Marine Science Program, and Belle W. Baruch Inst. for Marine Biology and Coastal Research)

    1993-10-01

    Acute toxicity tests were performed on field-collected copepods (Microarthridion littorale) using the sediment-associated polychlorinated biphenyl (PCB) Aroclor 1254 (i.e., PCB concentrations in bulk sediments in the bound and/or unbound states). Three replicates of 50 adult copepods were exposed to five levels of PCB-contaminated sediments for 96 h and compared to untreated controls and solvent controls. LC50 concentrations were nearly twice as high for females as for males. To determine the effects of the PCB on reproductive output of the copepods, copulating pairs of Microarthridion littorale were allowed to reproduce in concentrations of Aroclor 1254-contaminated sediments below LC50 values. Two experimental trials with 10 and 15 replicates, each with one pair of Microarthridion littorale in copulus, were conducted for 12 d, the normal time needed for females to produce one set of nauplii and carry a second clutch of eggs. In both experiments, a significant decrease in number of nauplii was found with Aroclor contamination. Although NOECs were not determined, high concentrations of the sediment-associated Aroclor NOECs were required to affect mortality significantly, whereas lower levels impaired reproduction.

  3. Sublethal effects of copper sulphate compared to copper nanoparticles in rainbow trout (Oncorhynchus mykiss) at low pH: physiology and metal accumulation.

    Science.gov (United States)

    Al-Bairuty, Genan A; Boyle, David; Henry, Theodore B; Handy, Richard D

    2016-05-01

    A few studies have investigated the interaction between copper toxicity and water pH in fishes, but little is known about the effects of acidic pH on the toxicity of copper nanoparticles (Cu-NPs). This study aimed to describe the sub-lethal toxic effects of Cu-NPs compared to CuSO4 at neutral and acidic water pH values in juvenile rainbow trout. Fish were exposed in triplicate (3 tanks/treatment) to control (no added Cu), or 20μgl(-1) of either Cu as CuSO4 or Cu-NPs, at pH 7 and 5 in a semi-static aqueous exposure regime for up to 7 days. Acidification of the water altered the mean primary particle size (at pH 7, 60±2nm and pH 5, 55±1nm) and dialysis experiments to measure dissolution showed an increased release of dissolved Cu from Cu-NPs at pH 5 compared to pH 7. Copper accumulation was observed in the gills of trout exposed to CuSO4 and Cu-NPs at pH 7 and 5, with a greater accumulation from the CuSO4 treatment than Cu-NPs at each pH. The liver also showed Cu accumulation with both Cu treatments at pH 7 only, whereas, the spleen and kidney did not show measurable accumulation of Cu at any of the water pH values. Exposure to acid water caused changes in the ionoregulatory physiology of control fish and also altered the observed effects of Cu exposure; at pH 5, branchial Na(+)/K(+)-ATPase activity was greater than at pH 7 and the inhibition of Na(+)/K(+)-ATPase activity caused by exposure to CuSO4 at pH 7 was also not observed. There were some changes in haematology and depletion of plasma Na(+) at pH 7 and 5 due to Cu exposure, but there were few material-type or pH effects. Overall, the data show that the accumulation of Cu is greater from CuSO4 than Cu-NPs; however, understanding of the effects of low pH on bioavailability of CuSO4 may not be directly transferred to Cu-NPs without further consideration of the physico-chemical behaviour of Cu-NPs in acid water. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Sublethal effects of insecticide seed treatments on two nearctic lady beetles (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Moscardini, Valéria Fonseca; Gontijo, Pablo Costa; Michaud, J P; Carvalho, Geraldo Andrade

    2015-07-01

    Predatory insects often feed on plants or use plant products to supplement their diet, creating a potential route of exposure to systemic insecticides used as seed treatments. This study examined whether chlorantraniliprole or thiamethoxam might negatively impact Coleomegilla maculata and Hippodamia convergens when the beetles consumed the extrafloral nectar of sunflowers grown from treated seed. We reared both species on eggs of Ephestia kuehniella and then switched adult H. convergens to a diet of greenbugs, Schizaphis graminum, in order to induce oviposition in this species. Excised sunflower stems, either treated or control and refreshed every 48 h, were provided throughout larval development, or for the first week of adult life. Exposure of C. maculata larvae to chlorantraniliprole and thiamethoxam applied as seed treatments delayed adult emergence by prolonging the pupal period. When adults were exposed, thiamethoxam reduced the preoviposition period compared to chlorantraniliprole, whereas the latter treatment cause females to produce fewer clutches during the observation period. Larvae of C. maculata did not appear to obtain sufficient hydration from the sunflower stems and their subsequent fecundity and fertility were compromised in comparison to the adult exposure experiment where larvae received supplemental water during development. Exposure of H. convergens larvae to thiamethoxam skewed the sex ratio in favor of females; both materials reduced the egg viability of resulting adults and increased the period required for eclosion. Exposure of H. convergens adults to chlorantraniliprole reduced egg eclosion times compared to thiamethoxam and exposure to both insecticides reduced pupation times in progeny. The results indicate that both insecticides have negative, sublethal impacts on the biology of these predators when they feed on extrafloral nectar of sunflower plants grown from treated seed.

  5. Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids.

    Science.gov (United States)

    Miles, Jesse C; Hua, Jessica; Sepulveda, Maria S; Krupke, Christian H; Hoverman, Jason T

    2017-01-01

    The widespread usage of neonicotinoid insecticides has sparked concern over their effects on non-target organisms. While research has largely focused on terrestrial systems, the low soil binding and high water solubility of neonicotinoids, paired with their extensive use on the landscape, puts aquatic environments at high risk for contamination via runoff events. We assessed the potential threat of these compounds to wetland communities using a combination of field surveys and experimental exposures including concentrations that are representative of what invertebrates experience in the field. In laboratory toxicity experiments, LC50 values ranged from 0.002 ppm to 1.2 ppm for aquatic invertebrates exposed to clothianidin. However, freshwater snails and amphibian larvae showed high tolerance to the chemical with no mortality observed at the highest dissolvable concentration of the insecticide. We also observed behavioral effects of clothianidin. Water bugs, Belostoma flumineum, displayed a dose-dependent reduction in feeding rate following exposure to clothianidin. Similarly, crayfish, Orconectes propinquus, exhibited reduced responsiveness to stimulus with increasing clothianidin concentration. Using a semi-natural mesocosm experiment, we manipulated clothianidin concentration (0.6, 5, and 352 ppb) and the presence of predatory invertebrates to explore community-level effects. We observed high invertebrate predator mortality with increases in clothianidin concentration. With increased predator mortality, prey survival increased by 50% at the highest clothianidin concentration. Thus, clothianidin contamination can result in a top-down trophic cascade in a community dominated by invertebrate predators. In our Indiana field study, we detected clothianidin (max = 176 ppb), imidacloprid (max = 141 ppb), and acetamiprid (max = 7 ppb) in soil samples. In water samples, we detected clothianidin (max = 0.67 ppb), imidacloprid (max = 0.18 ppb), and thiamethoxam (max = 2

  6. Effects of clothianidin on aquatic communities: Evaluating the impacts of lethal and sublethal exposure to neonicotinoids.

    Directory of Open Access Journals (Sweden)

    Jesse C Miles

    Full Text Available The widespread usage of neonicotinoid insecticides has sparked concern over their effects on non-target organisms. While research has largely focused on terrestrial systems, the low soil binding and high water solubility of neonicotinoids, paired with their extensive use on the landscape, puts aquatic environments at high risk for contamination via runoff events. We assessed the potential threat of these compounds to wetland communities using a combination of field surveys and experimental exposures including concentrations that are representative of what invertebrates experience in the field. In laboratory toxicity experiments, LC50 values ranged from 0.002 ppm to 1.2 ppm for aquatic invertebrates exposed to clothianidin. However, freshwater snails and amphibian larvae showed high tolerance to the chemical with no mortality observed at the highest dissolvable concentration of the insecticide. We also observed behavioral effects of clothianidin. Water bugs, Belostoma flumineum, displayed a dose-dependent reduction in feeding rate following exposure to clothianidin. Similarly, crayfish, Orconectes propinquus, exhibited reduced responsiveness to stimulus with increasing clothianidin concentration. Using a semi-natural mesocosm experiment, we manipulated clothianidin concentration (0.6, 5, and 352 ppb and the presence of predatory invertebrates to explore community-level effects. We observed high invertebrate predator mortality with increases in clothianidin concentration. With increased predator mortality, prey survival increased by 50% at the highest clothianidin concentration. Thus, clothianidin contamination can result in a top-down trophic cascade in a community dominated by invertebrate predators. In our Indiana field study, we detected clothianidin (max = 176 ppb, imidacloprid (max = 141 ppb, and acetamiprid (max = 7 ppb in soil samples. In water samples, we detected clothianidin (max = 0.67 ppb, imidacloprid (max = 0.18 ppb, and

  7. Acute toxicity of antimony chloride and its effects on oxygen consumption of common carp (Cyprinus carpio).

    Science.gov (United States)

    Chen, L-H; Yang, J-L

    2007-06-01

    The purposes of this study were to investigate the acute toxicity and effects of sublethal antimony (sb) concentrations on respiratory activity changes in the common carp (Cyprinus carpio). Median lethal concentrations were determined in acute tests. The 96-h LC50 value was 14.05 (11.09~17.80) mg L(-1). Common carp were exposed to 4 different sublethal levels of antimony (1.0, 2.0, 4.0, and 8.0 mg L(-1)) over a 28-day test period and a 14-day recovery period. On days 14 and 28, decreases in oxygen consumption were significant (p recovery period (on day 42) compared to the respective groups at the same level on day 28 at the higher exposure levels.

  8. Simulation of a Hazardous and Noxious Substances (HNS) spill in the marine environment: lethal and sublethal effects of acrylonitrile to the European seabass.

    Science.gov (United States)

    Neuparth, T; Capela, R; Rey-Salgueiro, L; Moreira, S M; Santos, M M; Reis-Henriques, M A

    2013-10-01

    Despite the extensive maritime transportation of Hazardous and Noxious Substances (HNS), there is a current lack of knowledge on the effects posed by HNS spills on the marine biota. Among the HNS identified as priority, acrylonitrile was selected to conduct ecotoxicological assays. We assessed the acute and subletal effects of acrylonitrile in seabass, followed by a recovery phase to simulate the conditions of a spill incident. The work aimed at testing a broad range of biological responses induced by acrylonitrile. Sublethal exposure to the highest two doses increased the fish mortality rate (8.3% and 25% mortality in 0.75 and 2 mg L(-1) acrylonitrile concentrations), whereas no mortality were observed in control and 0.15 mg L(-1) treatments. Additionally, important alterations at sub-individual level were observed. Acrylonitrile significantly induced the activities of Catalase- CAT and Glutathione S-Transferase - GST; and the levels of DNA damage were significantly increased. Conversely, Superoxide Dismutase- SOD - activity was found to be significantly inhibited and no effects were found on Lipid Peroxidation- LPO and ethoxyresorufin O-deethylase - EROD - activity. Following a 7d recovery period, the levels of CAT, GST and EROD fell to levels at or below those in the control. In the 2 mg L(-1) group, SOD remained at the levels found during exposure phase. This study has gathered essential information on the acute and subletal toxicity of acrylonitrile to seabass. It also demonstrated that 7d recovery allowed a return of most endpoints to background levels. These data will be useful to assist relevant bodies in preparedness and response to HNS spills. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. The sublethal effects of copper and lead on the haematology and ...

    African Journals Online (AJOL)

    Toxicity bioassays were conducted on groovy mullet, Liza dumerili, using copper and lead, in order to assess how these metals affected their blood haematology and acid-base balance. Short-term (96 hours) exposure to lead caused significantly more haematological response [PCO2] than copper, when compared to the ...

  10. Sublethal effects of cadmium, manganese, lead, zinc and iron on the ...

    African Journals Online (AJOL)

    caleb

    carried out in acute toxicity test) while control group was administered distilled water only. The metallic salts of the corresponding heavy metals of 1000 mg each of the salt was weighed out and diluted in 20 ml of distilled water. Solution of 0.1 ml was administered through cannular method to the mice over the. Osuala et al.

  11. Sublethal and Transgenerational Effects of Abamectin on the Biological Performance of the Predatory Thrips Scolothrips longicornis (Thysanoptera: Thripidae).

    Science.gov (United States)

    Pakyari, Hajar; Enkegaard, Annie

    2015-04-01

    Determination of sublethal and transgenerational effects of pesticides on natural enemies is necessary for successful implementation of biocontrol in integrated pest management programs. In this study, these effects of abamectin on the predatory thrips Scolothrips longicornis Priesner fed on Tetranychus urticae Koch were estimated under laboratory conditions in which adult predators were exposed to pesticide residues on bean leaves. The estimated values of LC50 for female and male predators were 0.091 and 0.067 µg a.i./ml, respectively. Low-lethal concentrations (LC10, LC20 and LC30) of abamectin severely affected fecundity and longevity of treated females of S. longicornis. In addition, transgenerational effects on reproductive and life table parameters of the subsequent generation were observed. The results from this research can be used to develop guidelines for the use of abamectin to minimize the impact on S. longicornis. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Sublethal effects of subzero temperatures on the light brown apple moth, Epiphyas postvittana: fitness costs in response to partial freezing.

    Science.gov (United States)

    Morey, Amy C; Venette, Robert C; Hutchison, William D

    2017-11-28

    Population responses to environmental extremes often dictate the bounds to species' distributions. However, population dynamics at, or near, those range limits may also be affected by sublethal effects. We exposed late instars and pupae of an invasive leafroller, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), to cold temperatures and measured the effects of exposure on subsequent survivorship, development, and reproduction. Cold temperature was applied as acute exposure to -10 °C (a low, but not immediately lethal temperature for this species) or the onset of freezing (the peak of the supercooling point exotherm). Survival was defined as the ability to successfully eclose as an adult. We measured immature development times, pupal mass, and adult longevity as proxies of fitness in survivors. Additionally, surviving insects were mated with individuals that had not been exposed to cold to measure fertility. There was no difference between the proportion of larvae or pupae that survived acute exposure to -10 °C and those exposed to the control temperature. Approximately 17% of larvae and 8% of pupae survived brief periods with internal ice formation and continued development to become reproductively viable adults. Importantly, surviving the onset of freezing came with significant fitness costs but not to exposure to -10 °C; most insects that survived partial freezing had lower fertility and shorter adult lifespans than either the -10 °C or control group. These results are discussed within the context of forecasting invasive insect distributions. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  13. Sub-lethal effects of fenbutatin oxide on prey location by the predatory mite Iphiseiodes zuluagai (Acari: Phytoseiidae).

    Science.gov (United States)

    Teodoro, Adenir V; Pallini, Angelo; Oliveira, Claudinei

    2009-04-01

    We used a Y-tube olfactometer to assess the sub-lethal effects of the acaricide fenbutatin oxide on the olfactory response of the predatory mite Iphiseiodes zuluagai towards odours from: (1) air or undamaged coffee plants; (2) undamaged or red spider mite Oligonychus ilicis-infested coffee plants; (3) undamaged or false spider mite Brevipalpus phoenicis-infested coffee plants. Predatory mite adult females were exposed to residues of fenbutatin oxide or distilled water on leaf discs during a period of 72 h prior experiments. When exposed to distilled water (control treatments), predatory mites significantly preferred undamaged plants over air, O. ilicis-infested plants over undamaged plants, and they did not prefer B. phoenicis-infested plants over undamaged plants. However, predatory mites that had been exposed to residues of fenbutatin oxide were neither attracted towards undamaged plants nor to O. ilicis-infested plants. Thus, fenbutatin oxide affected negatively the olfactory response of I. zuluagai. We conclude that sub-lethal-effect studies should be considered in pesticide selectivity programs since the ability of predatory mites to locate their prey may be negatively affected by non-lethal concentrations of pesticides.

  14. Bioaccumulation of organic micropollutants in different aquatic organisms. Sublethal toxic effects on fish

    NARCIS (Netherlands)

    van der Oost, Ron; Heida, Henk; Opperhuizen, Antoon; Vermeulen, Nico P E

    1991-01-01

    Bioaccumulation of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) was investigated in plankton, crustaceans, and fish from two relatively small Amsterdam lakes, with different levels of contamination. Ratios between contaminant

  15. Sublethal Toxic effects of spent Oil Based Drilling Mud and Cuttings ...

    African Journals Online (AJOL)

    The procedure for the exposure was according to the Organisation for Economic Co-operation and Development (OECD) recommended method for testing chemicals No 207. There were three replicate jars per treatment and 10 earthworms per jar of soil spiked with drilling mud. Control groups were also set up. At the end ...

  16. Toxicity study of diethyl phthalate on Clarias gariepinus fingerlings

    African Journals Online (AJOL)

    sunny t

    2014-02-12

    Feb 12, 2014 ... Therefore, a study was designed to determine the acute toxicity effects of DEP on a fresh water fish,. Clarias gariepinus ... Key words: Diethyl phthalate, Clarias gariepinus, acute toxicity, sublethal toxicity, heamatology, biochemical, histopathology ..... discharge of DEP-laden effluents and wastes take place.

  17. Effects of sub-lethal doses of photo-activated disinfection against Porphyromonas gingivalis for pharmaceutical treatment of periodontal-endodontic lesions.

    Science.gov (United States)

    Pourhajibagher, Maryam; Chiniforush, Nasim; Raoofian, Reza; Ghorbanzadeh, Roghayeh; Shahabi, Sima; Bahador, Abbas

    2016-12-01

    Microorganisms treated by photo-activated disinfection (PAD) in combined periodontal-endodontic (perio-endo) lesions would be exposed to sub-lethal doses of PAD (sPAD). This study evaluated the effect of sPAD using toluidine blue O (TBO) in combination with diode laser irradiation on the growth and biofilm-formation ability of Porphyromonas gingivalis as an endo-periodontal pathogen. The antibacterial and antibiofilm potential of sPAD against P. gingivalis was analyzed at sub-lethal doses of TBO and irradiation time of diode laser on a colony-forming unit and crystal violet assays, respectively. TBO-mediated PAD, using 6.25-100μg/mL at a fluency of 171.87J/cm(2) and 12.5-100μg/mL at a fluency of 137.5J/cm(2), showed a significant dose-dependent reduction in P. gingivalis growth when compared to the control. TBO-mediated PAD showed a significantly inhibitory effect on biofilm formation in P. gingivalis than TBO-PAD at sub-lethal levels. High doses of sPAD revealed antibacterial and antibiofilm potential activity, whereas lower doses of sPAD had conflicting results. Therefore, when PAD is prescribed in combined perio-endo lesions treatment, the dose of PAD used in vivo should be taken into account. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Evaluating sub-lethal effects of orchard-applied pyrethroids using video-tracking software to quantify honey bee behaviors.

    Science.gov (United States)

    Ingram, Erin M; Augustin, Julie; Ellis, Marion D; Siegfried, Blair D

    2015-09-01

    Managed honey bee, Apis mellifera L., colonies are contracted to pollinate fruit and nut orchards improving crop quality and yield. Colonies placed in orchards are potentially exposed to pyrethroid insecticides used for broad-spectrum pest control. Pyrethroids have been reported to pose minimal risk to bees due to their low application rates in the field and putative repellent properties. This repellency is believed to alter foraging behavior with the benefit of preventing bees from encountering a lethal dose in the field. However, sub-lethal exposure to pyrethroids may adversely impact bee behavior potentially resulting in social dysfunction or disruption of foraging. This study quantified behaviors associated with sub-lethal exposure to orchard-applied pyrethroids including, lambda-cyhalothrin, esfenvalerate, and permethrin, using video tracking software, Ethovision XT (Noldus Information Technologies). Bee locomotion, social interaction, and time spent near a food source were measured over a 24-h period. Bees treated with a pyrethroid traveled 30-71% less than control bees. Social interaction time decreased by 43% for bees treated with a high sub-lethal dose of esfenvalerate. Bees exposed to a high sub-lethal dose of permethrin spent 67% less time in social interaction and spent more than 5 times as long in the food zone compared to control bees. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Sublethal Effects of Imidacloprid on Honey Bee Colony Growth and Activity at Three Sites in the U.S.

    Science.gov (United States)

    Meikle, William G; Adamczyk, John J; Weiss, Milagra; Gregorc, Ales; Johnson, Don R; Stewart, Scott D; Zawislak, Jon; Carroll, Mark J; Lorenz, Gus M

    2016-01-01

    Imidacloprid is a neonicotinoid pesticide heavily used by the agricultural industry and shown to have negative impacts on honey bees above certain concentrations. We evaluated the effects of different imidacloprid concentrations in sugar syrup using cage and field studies, and across different environments. Honey bee colonies fed sublethal concentrations of imidicloprid (0, 5, 20 and 100 ppb) over 6 weeks in field trials at a desert site (Arizona), a site near intensive agriculture (Arkansas) and a site with little nearby agriculture but abundant natural forage (Mississippi) were monitored with respect to colony metrics, such as adult bee and brood population sizes, as well as pesticide residues. Hive weight and internal hive temperature were monitored continuously over two trials in Arizona. Colonies fed 100 ppb imidacloprid in Arizona had significantly lower adult bee populations, brood surface areas and average frame weights, and reduced temperature control, compared to colonies in one or more of the other treatment groups, and consumption rates of those colonies were lower compared to other colonies in Arizona and Arkansas, although no differences in capped brood or average frame weight were observed among treatments in Arkansas. At the Mississippi site, also rich in alternative forage, colonies fed 5 ppb imidacloprid had less capped brood than control colonies, but contamination of control colonies was detected. In contrast, significantly higher daily hive weight variability among colonies fed 5 ppb imidacloprid in Arizona suggested greater foraging activity during a nectar flow post treatment, than any other treatment group. Imidacloprid concentrations in stored honey corresponded well with the respective syrup concentrations fed to the colonies and remained stable within the hive for at least 7 months after the end of treatment.

  20. Effect of prolonged exposure to sublethal concentrations of DDT and DDE on protein expression in human pancreatic beta cells.

    Science.gov (United States)

    Pavlikova, Nela; Smetana, Pavel; Halada, Petr; Kovar, Jan

    2015-10-01

    Pollution of the environment represents one of less explored potential reasons for the worldwide epidemic of type 2 diabetes. One of the most prevalent organochlorine pollutants remains the pesticide DDT and its degradation product DDE. Despite some epidemiologic correlations between levels of DDT and DDE in human organism and the prevalence of diabetes, there is almost no information about the exact targets of these compounds inside pancreatic beta cells. To detect functional areas of pancreatic beta cells that could be affected by exposure to DDT and DDE, we analyzed changes in protein expression in the NES2Y human pancreatic beta cell line exposed to three sublethal concentrations (0.1 μM, 1 μM, 10 μM) of DDT and DDE for 1 month. Protein separation and identification was achieved using high-resolution 2D-electrophoresis, computer analysis and mass spectrometry. With these techniques, four proteins were found downregulated after exposure to 10 μM DDT: three cytoskeletal proteins (cytokeratin 8, cytokeratin 18 and actin) and one protein involved in glycolysis (alpha-enolase). Two proteins were downregulated after exposure to 10 μM DDE: cytokeratin 18 and heterogenous nuclear ribonucleoprotein H1 (HNRH1). These changes correlate with previously described effects of other stress conditions (e.g. exposure to palmitate, hyperglycemia, imidazoline derivative, and cytokines) on protein expression in pancreatic beta cells. We conclude that cytoskeletal proteins and their processing, glucose metabolism, and mRNA processing may represent targets affected by exposure to conditions hostile to pancreatic beta cells, including exposure to DDT and DDE. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Sublethal effects of abamectin and fenpropathrin on the consumption of Tetranychus urticae eggs by Scolothrips longicornis

    DEFF Research Database (Denmark)

    Pakyari, Hajar; Enkegaard, Annie

    2015-01-01

    consumption rates of exposed females of Scolothrips longicornis Priesner and their offspring when fed on Tetranychus urticae Koch eggs. Prey consumption of female thrips was significantly affected by treatment with all concentrations of the two pesticides with the effect of fenpropathrin being more severe...

  2. Scaling the sublethal effects of methylmercury to yellow perchs population dynamics using adverse outcome pathway framework

    Science.gov (United States)

    This study sought to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and zebrafish (Danio rerio) reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, a...

  3. Lethal and Sublethal Effects of Fenpropathrin on the Biological Performance of Scolothrips longicornis (Thysanoptera: Thripidae)

    DEFF Research Database (Denmark)

    Pakyari, Hajar; Enkegaard, Annie

    2013-01-01

    affected the biological characteristics of treated females of S. longicornis, the most noticeable effects being a shortening of female life span by >70% accompanied by large reductions in oviposition period and fecundity. The offspring of females treated with low-lethal concentrations of fenpropathrin...... likewise had significantly reduced longevity, oviposition period, and fecundity, although not to the same extent as experienced by their mothers. Their juvenile development time was, however, not affected. These effects on the offspring were reflected in reduced rates of population increase and increased......: Thripidae) fed on Tetranychus urticae Koch (Acari: Tetranychidae) were evaluated under laboratory conditions. The estimated values of LC50 for female and male predators were 6.53 and 5.47 μg a.i./ml, respectively. Exposure to low-lethal concentrations (LC10, LC20, and LC30) of fenpropathrin significantly...

  4. Lethal and Sub-lethal Effects of UVB on Juvenile Biomphalaria glabrata (Mollusca: Pulmonata)

    OpenAIRE

    Ruelas, Debbie S.; Karentz, Deneb; Sullivan, John T.

    2006-01-01

    Although Schistosoma mansoni occurs mainly in the tropics, where intense levels of solar radiation are present, the impact of ultraviolet (UV) light on schistosome transmission is not known. The purpose of this study was to investigate potential effects of UVB (290–320 nm) on juvenile Biomphalaria glabrata, the snail intermediate host of S. mansoni. Albino and wild type snails were exposed to doses of UVB from UV-fluorescent lamps, and the following were measured: survival, photoreactivation ...

  5. Morphometric Modifications in Canthon quinquemaculatus Castelnau 1840 (Coleoptera: Scarabaeinae: Sublethal Effects of Transgenic Maize?

    Directory of Open Access Journals (Sweden)

    Victor Michelon Alves

    2017-10-01

    Full Text Available The effects of transgenic compounds on non-target organisms remain poorly understood, especially in native insect species. Morphological changes (e.g., changes in body size and shape may reflect possible responses to environmental stressors, like transgenic toxins. The dung beetle Canthon quinquemaculatus (Coleoptera: Scarabaeinae is a non-target species found in transgenic crops. We evaluated whether C. quinquemaculatus individuals inhabiting corn fields cultivated with different seed types (conventional, creole and transgenic present modifications in body shape compared to individuals inhabiting adjacent native forest fragments. We collected C. quinquemaculatus specimens across an agricultural landscape in southern Brazil, during the summer of 2015. Six populations were sampled: three maize crop populations each under a different seed type, and three populations of adjacent forests. After sampling, specimens were subjected to morphometric analyses to discover differences in body shape. We chose fifteen landmarks to describe body shape, and morphometric data were tested with Procrustes ANOVA and Discriminant Analysis. We found that body shape did not differ between individuals collected in conventional and creole crops with their respective adjacent forests (p > 0.05; however, transgenic crop populations differed significantly from those collected in adjacent forests (p < 0.05. Insects in transgenic maize are more oval and have a retraction in the abdominal region, compared with the respective adjacent forest, this result shows the possible effect of transgenic crops on non-target species. This may have implications for the ecosystem service of organic matter removal, carried out by these organisms.

  6. Lethal and sub-lethal effects of thymol on honeybee (Apis mellifera) larvae reared in vitro.

    Science.gov (United States)

    Charpentier, Gael; Vidau, Cyril; Ferdy, Jean-Baptiste; Tabart, Jeremy; Vetillard, Angelique

    2014-01-01

    Thymol offers an attractive alternative to synthetic chemicals to keep Varroa under control. However, thymol accumulates in bee products and is suspected of having adverse effects on colonies and especially on larvae. In this study, we investigated the effects of acute and chronic exposure to thymol on larvae reared in vitro with contaminated food and compared results to the theoretical larval exposure based on the amount of pollen and honey consumed by larvae during their development. The laboratory assays reveal that, first, the 48 h-LD50 of thymol introduced into larval food is 0.044 mg larva(-1) . Second, the 6 day-LC50 is 700 mg kg(-1) food. A significant decrease of larval survival and mass occurred from 500 mg thymol kg(-1) food (P thymol kg(-1) food (P thymol residue found in honey and pollen, these results suggest that the contamination of food by thymol represents no notable risk for the early-developing larvae. © 2013 Society of Chemical Industry.

  7. Fipronil promotes motor and behavioral changes in honey bees (Apis mellifera) and affects the development of colonies exposed to sublethal doses.

    Science.gov (United States)

    Zaluski, Rodrigo; Kadri, Samir Moura; Alonso, Diego Peres; Martins Ribolla, Paulo Eduardo; de Oliveira Orsi, Ricardo

    2015-05-01

    Bees play a crucial role in pollination and generate honey and other hive products; therefore, their worldwide decline is cause for concern. New broad-spectrum systemic insecticides such as fipronil can harm bees and their use has been discussed as a potential threat to bees' survival. In the present study, the authors evaluate the in vitro toxicity of fipronil and note behavioral and motor activity changes in Africanized adult Apis mellifera that ingest or come into contact with lethal or sublethal doses of fipronil. The effects of sublethal doses on brood viability, population growth, behavior, and the expression of the defensin 1 gene in adult bees were studied in colonies fed with contaminated sugar syrup (8 µg fipronil L(-1) ). Fipronil is highly toxic to bees triggering agitation, seizures, tremors, and paralysis. Bees that are exposed to a lethal or sublethal doses showed reduced motor activity. The number of eggs that hatched, the area occupied by worker eggs, and the number of larvae and pupae that developed were reduced, adult bees showed lethargy, and colonies were abandoned when they were exposed to sublethal doses of fipronil. No change was seen in the bees' expression of defensin 1. The authors conclude that fipronil is highly toxic to honey bees and even sublethal doses may negatively affect the development and maintenance of colonies. © 2015 SETAC.

  8. Lethal and sub-lethal chronic effects of the herbicide diuron on seagrass

    Energy Technology Data Exchange (ETDEWEB)

    Negri, Andrew P., E-mail: a.negri@aims.gov.au [Australian Institute of Marine Science, Townsville, Queensland 4810 (Australia); Flores, Florita [Australian Institute of Marine Science, Townsville, Queensland 4810 (Australia); Mercurio, Phil [Australian Institute of Marine Science, Townsville, Queensland 4810 (Australia); University of Queensland and National Research Centre for Environmental Toxicology, Coopers Plains, Queensland 4108 (Australia); Mueller, Jochen F. [University of Queensland and National Research Centre for Environmental Toxicology, Coopers Plains, Queensland 4108 (Australia); Collier, Catherine J. [Centre for Tropical Water & Aquatic Ecosystem Research (TropWATER), James Cook University, Cairns, Queensland 4870 (Australia)

    2015-08-15

    Highlights: • We performed chronic exposures of two seagrass species to the herbicide diuron. • Diuron affected photosystem II (PSII) at 0.3 μg l{sup −1} and growth at 7.2 μg l{sup −1}. • Biomarkers indicated that carbon-assimilation from photosynthesis dropped following 0.6 μg l{sup −1} diuron exposure. • Energetic reserves in the seagrass were halved at 1.7 μg l{sup −1} after 11 weeks. • Chronic exposure to diuron is likely to enhance the impacts of low light stress during flood plumes - Abstract: Photosystem II herbicides from agricultural sources have been detected throughout nearshore tropical habitats including seagrass meadows. While PSII herbicides have been shown to inhibit growth in microalgae at low concentrations, the potential impacts of chronic low concentration exposures to seagrass health and growth have not been investigated. Here we exposed two tropical seagrass species Halodule uninervis and Zostera muelleri to elevated diuron concentrations (from 0.3 to 7.2 μg l{sup −1}) over a 79-day period followed by a 2-week recovery period in uncontaminated seawater. PAM fluorometry demonstrated rapid effect of diuron on photosystem II (PSII) in both seagrass species at 0.3 μg l{sup −1}. This effect included significant inhibition of photosynthetic efficiency (ΔF/F{sub m}′) and inactivation of PSII (F{sub v}/F{sub m}) over the 11 week exposure period. Significant mortality and reductions in growth was only observed at the highest exposure concentration of 7.2 μg l{sup −1} diuron. However, biochemical indicators demonstrated that the health of seagrass after this prolonged exposure was significantly compromised at lower concentrations. For example, the drop in C:N ratios (0.6 μg l{sup −1}) and reduced δ{sup 13}C (1.7 μg l{sup −1}) in seagrass leaves indicated reduced C-assimilation from photosynthesis. Critically, the energetic reserves of the plants (as measured by starch content in the root-rhizome complex) were

  9. Sub-lethal effects of energy development on a migratory mammal—The enigma of North American pronghorn

    Directory of Open Access Journals (Sweden)

    Jon P. Beckmann

    2016-04-01

    (Pinedale Anticline Project Area [PAPA] and Jonah fields and other behavioral or ecological observations of sub-lethal effects, we failed to reject the null hypothesis that development is unrelated to parity in pronghorn biological responses. Studies intent on producing knowledge to assess whether energy development is inimical or not to ungulates will increasingly require appropriate time scales and understanding whether populations are below an expected food ceiling. Further, as with pronghorn in our study region, knowing if individuals are at the limits of their biological range (e.g. altitude where stressful winter conditions may mask impacts of development is important.

  10. Toxic effects of orimulsion on rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Svecevicius, Gintaras; Kazlauskiene, Nijole; Vosyliene, Milda Z

    2003-01-01

    Orimulsion (stable emulsion of natural bitumen and water) is a new imported industrial fuel in Lithuania. No data on its toxicity to fish is freely available. The aim of this study was to investigate sensitivity of rainbow trout (Oncorhynchus mykiss) to acute and chronic toxicity of orimulsion and to estimate the Maximum Acceptable Toxicant Concentration (MATC) of orimulsion to fish. Laboratory tests were conducted on rainbow trout in all stages of development (embryos, larvae, adults). Acute toxicity (96-hour duration) and long-term (28 or 60-day duration) tests evaluating the wide range spectrum of biological indices were performed under semi-static conditions. Median lethal concentration (96-hour LC50) values and their 95% confidence intervals derived from the tests were: 0.1 (0.09-0.12) to embryos, 0.06 (0.05-0.07) to larvae and 2.22 (2.02-2.43) to adult fish, and 28-day LC50 to adult fish was found to be 0.26 (0.21-0.32) g/l of total orimulsion respectively. The acute toxicity of orimulsion to rainbow trout can be characterised by a narrow zone of toxic effect and a sharp boundary between lethal and sublethal concentrations. The lowest 'safe' or 'no-effect' concentration values of total orimulsion obtained in long-term tests were equal to 0.09 g/l to adult fish, 0.019 g/l to embryos, and 0.0017 g/l to larvae. Proposed value of 'application factor' for orimulsion was found to be equal to 0.03. Since orimulsion has the property to disperse in all water volume, its toxic effect on fish can be characterised by the combined effects of dispersion and water-soluble-fraction. Maximum Acceptable Toxicant Concentration (MATC) of 0.0017 g/l of total orimulsion to fish was derived from long-term tests based on the most sensitive parameter of rainbow trout larvae (relative mass increase at the end of the test). According to substance toxicity classification accepted for Lithuanian inland waters, orimulsion can be referred to substances of 'moderate' toxicity to fish. For

  11. Effects of spirotetramat on the acute toxicity, oxidative stress, and lipid peroxidation in Chinese toad (Bufo bufo gargarizans) tadpoles.

    Science.gov (United States)

    Yin, XiaoHui; Jiang, ShengJu; Yu, Jun; Zhu, GuoNian; Wu, HuiMing; Mao, ChenLei

    2014-05-01

    The aim of this work was to evaluate the potential effects of antioxidant and lipid peroxidation parameters as indicators of exposure to spirotetramat and effects of acute toxicity in the Chinese toad Bufo bufo gargarizans. The results of an acute toxicity test showed that the 72 and 96 h median lethal concentrations (LC(50)) of spirotetramat for tadpoles were 6.98 and 6.45 mg/L, respectively. It indicated that the spirotetramat was moderate toxicity to Chinese toad tadpoles. In a sub-lethal toxicity test, the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) contents were determined after exposure to 0.03, 0.06, 0.13, 0.65, and 3.23 mg/L for 4, 15, and 30 days. SOD activity significantly in all experimental groups except the highest concentration group increased on day 4 but decreased on days 15 compared with that of the acetone control (P < 0.05). The most sensitive parameters was GSH-Px activity, which significantly increased on day 4, but was inhibited and decreased after prolonged exposure for 15 and 30 days except the lowest concentration treatment group (P < 0.05). The MDA content significantly decreased on day 30 (P < 0.05). During the entire experimental period, sub-lethal doses spirotetramat caused oxidative stress and lipid peroxidation in B. gargarizans tadpoles. These results indicate that sub-lethal even non-lethal spirotetramat are potentially toxic to amphibians. The information presented in this study will be helpful for understanding oxidative stress induced by spirotetramat in aquatic organisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells

    Energy Technology Data Exchange (ETDEWEB)

    Flaskos, J., E-mail: flaskos@vet.auth.gr [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Nikolaidis, E. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Harris, W. [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Sachana, M. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Hargreaves, A.J., E-mail: alan.hargreaves@ntu.ac.uk [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

    2011-11-15

    Previous work in our laboratory has shown that sub-lethal concentrations (1-10 {mu}M) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1-10 {mu}M) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: Black-Right-Pointing-Pointer Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells Black-Right-Pointing-Pointer Acetylcholinesterase exhibits sustained inhibition throughout exposure Black-Right-Pointing-Pointer The levels of neurofilament heavy chain and GAP-43

  13. Sublethal effects of chlorantraniliprole on juvenile hormone levels and mRNA expression of JHAMT and FPPS genes in the rice stem borer, Chilo suppressalis.

    Science.gov (United States)

    Xu, Beibei; Qian, Kun; Zhang, Nan; Miao, Lijun; Cai, Jingxuan; Lu, Mingxing; Du, Yuzhou; Wang, Jianjun

    2017-10-01

    Juvenile hormone (JH) regulates the development and reproduction of insects. The sublethal effects of chlorantraniliprole on JH levels and mRNA expression of JH acid methyltransferase gene (CsJHAMT) and farnesyl diphosphate synthase genes (CsFPPS1 and CsFPPS2) in Chilo suppressalis (Walker) were investigated. Exposure of sublethal concentrations of chlorantraniliprole (LC10 and LC30 ) to the third instar larvae of C. suppressalis significantly increased the JH levels in all developmental stages investigated including larvae 72 h after treatment, the first, third and fifth day of female pupae, as well as newly emerged, 12-h-old and 24-h-old female adults. A general trend of increased mRNA expression levels of CsJHAMT, CsFPPS1and CsFPPS2 was also observed in LC10 and LC30 treatment groups. Notably, the mRNA expression level of CsJHAMT significantly increased by 7.46-fold in the larvae 72 h after LC30 treatment. A significant increase of the mRNA expression levels of CsFPPS2 was also observed in the fifth day female pupae of LC10 and LC30 treatment groups (2.60-fold and 2.62-fold, respectively) as well as in 12-h-old female adults of the LC30 treatment group (3.45-fold). Sublethal concentrations of chlorantraniliprole might upregulate the expression of JH biosynthesis genes and in turn result in an increase of JH level in C. suppressalis. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Lethal and sublethal effects of bendiocarb, halofenozide, and imidacloprid on Harpalus pennsylvanicus (Coleoptera: Carabidae) following different modes of exposure in turfgrass.

    Science.gov (United States)

    Kunkel, B A; Held, D W; Potter, D A

    2001-02-01

    Routes by which nontarget predatory insects can be exposed to turfgrass pesticides include topical, residual, and dietary exposure. We used each of these routes to evaluate potential lethal or sublethal effects of two novel turfgrass insecticides, imidacloprid and halofenozide, and a carbamate, bendiocarb, on survival, behavior, and fecundity of the ground beetle Harpalus pennsylvanicus DeGeer. Field-collected carabids were exposed to direct spray applications in turf plots, fed food contaminated by such applications, or exposed to irrigated or nonirrigated residues on turf cores. Halofenozide caused no apparent acute, adverse effects through topical, residual, or dietary exposure. Moreover, the viability of eggs laid by females fed halofenozide-treated food once, or continuously for 30 d, was not reduced. In contrast, topical or dietary exposure of carabids to bendiocarb inevitably was lethal. Exposure to imidacloprid by those routes caused high incidence of sublethal, neurotoxic effects including paralysis, impaired walking, and excessive grooming. Intoxicated beetles usually recovered within a few days in the laboratory, but in the field, they were shown to be highly vulnerable to predation by ants. One-time intoxication by imidacloprid did not reduce females' fecundity or viability of eggs. There was no apparent behavioral avoidance of insecticide residues, or of insecticide-treated food. Carabids exposed to dry residues on turfgrass cores suffered high mortality from bendiocarb, and some intoxication from imidacloprid, but these effects were greatly reduced by posttreatment irrigation. Implications for predicting hazards of insecticides to beneficial invertebrates in turfgrass are discussed.

  15. Gas chromatography-mass spectrometry based metabolomic approach for optimization and toxicity evaluation of earthworm sub-lethal responses to carbofuran.

    Directory of Open Access Journals (Sweden)

    Mohana Krishna Reddy Mudiam

    Full Text Available Despite recent advances in understanding mechanism of toxicity, the development of biomarkers (biochemicals that vary significantly with exposure to chemicals for pesticides and environmental contaminants exposure is still a challenging task. Carbofuran is one of the most commonly used pesticides in agriculture and said to be most toxic carbamate pesticide. It is necessary to identify the biochemicals that can vary significantly after carbofuran exposure on earthworms which will help to assess the soil ecotoxicity. Initially, we have optimized the extraction conditions which are suitable for high-throughput gas chromatography mass spectrometry (GC-MS based metabolomics for the tissue of earthworm, Metaphire posthuma. Upon evaluation of five different extraction solvent systems, 80% methanol was found to have good extraction efficiency based on the yields of metabolites, multivariate analysis, total number of peaks and reproducibility of metabolites. Later the toxicity evaluation was performed to characterize the tissue specific metabolomic perturbation of earthworm, Metaphire posthuma after exposure to carbofuran at three different concentration levels (0.15, 0.3 and 0.6 mg/kg of soil. Seventeen metabolites, contributing to the best classification performance of highest dose dependent carbofuran exposed earthworms from healthy controls were identified. This study suggests that GC-MS based metabolomic approach was precise and sensitive to measure the earthworm responses to carbofuran exposure in soil, and can be used as a promising tool for environmental eco-toxicological studies.

  16. Lethal and sublethal effects of methoxyphenozide on the development, survival and reproduction of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

    Energy Technology Data Exchange (ETDEWEB)

    Zarate, N.; Diaz, O. [Universidad Autonoma de San Luis Potosi (Mexico). Facultad de Agronomia; Martinez, A.M.; Figueroa, J.I.; Pineda, S., E-mail: spineda_us@yahoo.co [Universidad Michoacana de San Nicolas de Hidalgo, Tarimbaro, Michoacan (Mexico). Inst. de Investigaciones Agropecuarias y Forestales; Schneider, M.I. [National Council of Scientific and Technical Research (CEPAVE/CCT/CONICET), La Plata (Argentina). Centro de Estudios Parasitologicos y de Vectores. Centro Cientifico Tecnologico; Smagghe, G. [Ghent University, Ghent (Belgium). Faculty of Bioscience Engineering. Lab of Agrozoology; Vinuela, E.; Budia, F. [Escuela Tecnica Superior de Ingenieros Agronomos, Madrid (Spain). Escuela Tecnica Superior de Ingenieros Agronomos. Proteccion de Cultivos

    2011-01-15

    The lethal and sublethal effects of the ecdysone agonist methoxyphenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyphenozide-treated diet to fifth instars until pupation in doses corresponding to the LC{sub 10} and LC{sub 25} for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC{sub 10} and 60% for the LC{sub 25} was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm. (author)

  17. Sediment quality in the Guadalquivir estuary: sublethal effects associated with the Aznalcóllar mining spill.

    Science.gov (United States)

    Riba, I; González de Canales, M; Forja, J M; DelValls, T A

    2004-01-01

    As a complementary assessment of the impact of the Aznalcóllar mining spill on the Guadalquivir estuary two different sediment toxicity tests using fish (Solea senegalensis) and clams (Scrobicularia plana) were performed. The histopathological alterations by recording lesions at 15 and 30 days in fish to the gills, liver, gut and kidney and at 14 days in clams to the gills and gut were used to determine the adverse effects associated with the contaminants bound to sediments. The lesions measured at different tissues in both organisms show that the enrichment of heavy metals from the mining spill stressed some areas in the ecosystem of the estuary. The comparison of these effects with those lethal effects detected in the same samples using a multivariate analysis approach permits to identify the adverse effects associated with the accidental spill on the estuary. The incidence of the impact, located in specific areas of the estuary show an acute effect related to the spill.

  18. Effect of exposure to sublethal concentrations of sodium cyanide on the carbohydrate metabolism of the Indian Major Carp Labeo rohita (Hamilton, 1822

    Directory of Open Access Journals (Sweden)

    Praveen N. Dube

    2013-07-01

    Full Text Available Experiments were designed to study in-vivo effects of sodium cyanide on biochemical endpoints in the freshwater fish Labeo rohita. Fish were exposed to two sublethal concentrations (0.106 and 0.064mg/L for a period of 15 days. Levels of glycogen, pyruvate, lactate and the enzymatic activities of lactate dehydrogenase (LDH, succinate dehydrogenase (SDH, glucose-6-phosphate dehydrogenase (G6PDH, phosphorylase, alkaline phosphatase (ALP, acid phosphatase (AcP were assessed in different tissues (liver, muscle and gills. Result indicated a steady decrease in glycogen, pyruvate, SDH, ALP and AcP activity with a concomitant increase in the lactate, phosphorylase, LDH and G6PD activity in all selected tissues. The alterations in all the above biochemical parameters were significantly (p<0.05 time and dose dependent. In all the above parameters, liver pointing out the intensity of cyanide intoxication compare to muscle and gills. Study revealed change in the metabolic energy by means of altered metabolic profile of the fish. Further, these observations indicated that even sublethal concentrations of sodium cyanide might not be fully devoid of deleterious influence on metabolism in L. rohita.

  19. Lethal and sub-lethal effects of cypermethrin and glyphosate on the freshwater’s copepod, Acanthocyclops robustus

    OpenAIRE

    AM Houssou; EJ Daguégué; E Montchowui

    2017-01-01

    The study aims to evaluate the acute and chronic toxicity of cypermethrin and glyphosate to a freshwater’s copepod, Arcanthocyclops robustus. The acute sensibility was assessed by estimating lethal concentrations. Then the chronic exposure allowed to assess the effects of low concentrations (0.2489 ppb and 0.4978 ppb respectively 10 % and 20 % of LC50 at 48 h of cypermethrin and 1.3 ppm and 2.6 ppm respectively for glyphosate) on the species. The estimated lethal concentrations at...

  20. Bridging environmental mixtures and toxic effects.

    Science.gov (United States)

    Allan, Sarah E; Smith, Brian W; Tanguay, Robert L; Anderson, Kim A

    2012-12-01

    Biological Response Indicator Devices Gauging Environmental Stressors (BRIDGES) is a bioanalytical tool that combines passive sampling with the embryonic zebrafish developmental toxicity bioassay to provide a quantitative measure of the toxicity of bioavailable complex mixtures. Passive sampling devices (PSDs), which sequester and concentrate bioavailable organic contaminants from the environment, were deployed in the Willamette and Columbia Rivers within and outside of the Portland Harbor Superfund site in Portland, OR, USA. Six sampling events were conducted in the summer and fall of 2009 and 2010. Passive sampling device extracts were analyzed for polycyclic aromatic hydrocarbon (PAH) compounds and screened for 1,201 chemicals of concern using deconvolution-reporting software. The developmental toxicity of the extracts was analyzed using the embryonic zebrafish bioassay. The BRIDGES tool provided site-specific, temporally resolved information about environmental contaminant mixtures and their toxicity. Multivariate modeling approaches were applied to paired chemical and toxic effects data sets to help unravel chemistry-toxicity associations. Modeling elucidated spatial and temporal trends in PAH concentrations and the toxicity of the samples and identified a subset of PAH analytes that were the most highly correlated with observed toxicity. Although the present study highlights the complexity of discerning specific bioactive compounds in complex mixtures, it demonstrates methods for associating toxic effects with chemical characteristics of environmental samples. Copyright © 2012 SETAC.

  1. The Effect of Toxic Leadership

    Science.gov (United States)

    2012-03-15

    leaders are a product of their environment, unlike corporations that hire mid-level and senior level managers to guide their organizations; the...01674544. 5 Tomas Giberson and others, "Leadership and Organizational Culture: Linking Ceo Characteristics to Cultural Values," Journal of Business...Craig; Lim. 23 David Lease, "From Great to Ghastly: How Toxic Organizational Cultures Poison Companies the Rise and Fall of Enron , Worldcom, Healthsouth

  2. Protective effects of Eruca sativa (rocket) on abamectin insecticide toxicity in male albino rats.

    Science.gov (United States)

    Meligi, Noha M; Hassan, Hanaa Fawzy

    2017-04-01

    The extensive use of insecticides has hazardous effects since they can damage human health as well as the environment. Abamectin has been widely used in veterinary medicine and as a pesticide in agriculture. It is considered as one of the most commonly used insecticides in Egypt. The focus of the present study is to examine the toxic effects of sublethal dose (1 mg/kg b.wt.) of abamectin (Crater 3.37% EC) in male albino rats and to evaluate the efficiency of Eruca sativa suspension to ameliorate the abamectin toxicity. The present study was achieved using 18 male albino rats. Rats were divided into three groups: normal control group, abamectin-treated group, and abamectin + E. sativa-treated group. Rats of the third group were orally administrated a mixture of sublethal dose of abamectin (1 mg/kg b.wt.) and E. sativa suspension (5 g/kg b.wt.) three times a week for 28 days. At the end of the study period, blood samples were collected from all groups to measure the various hematological and biochemical parameters. The results revealed that rats, after abamectin exposure, exhibited general signs of toxicity and disturbance in the hematological and biochemical parameters. In addition, administration of E. sativa suspension ameliorated the hematological and biochemical parameters. These findings suggested that the exposure to abamectin might be responsible for hypertension, liver and kidney dysfunction, lipid profile disturbance, and oxidative stress, reflected in hematological and biochemical parameters. It was also found that the administration of E. sativa suspension reduced the detrimental impact of abamectin on some hematological and biochemical parameters.

  3. Effects of sublethal doses of crop protection agents on honey bee (Apis mellifera) global colony vitality and its potential link with aberrant foraging activity.

    Science.gov (United States)

    Beliën, T; Kellers, J; Heylen, K; Keulemans, W; Billen, J; Arckens, L; Huybrechts, R; Gobin, B

    2009-01-01

    Honey bees (Apis mellifera) are the most economically valuable pollinators of fruit crops worldwide. Taking into account bees' contributions to other flowering agricultural crops, about one-third of our total diet comes directly or indirectly from bee-pollinated plants. However, in recent years there increasingly have been worrisome alarm sounds on serious bee mortalities and mysterious disappearance of bees from beehives. Among several environmental factors (e.g. climate and bee pathogens), stress factors arising from agricultural practices can potentially play a role in bee losses. Detailed knowledge on the effects of plant protection products is essential to improve usage with minimal risks. In order to identify potential medium- and long-term effects, we followed up various sublethal contaminated hives during the prolongation of the fruit-growing season. More specifically, a large-scale experiment was conducted in which at four distinct locations (in the Limburg region of Belgium) four different bee colonies (representing three different contaminations -imidacloprid, fenoxycarb, indoxacarb- and a non-contaminated control hive) were thoroughly monitored every 2-7 days. Our observations point towards decays of overall colony vitality for several hives a couple of weeks after treatment, as indicated by a set of carefully assessed parameters including the total amount of active and dead bees, total surface of capped brood and overall colony weight. These outcomes could be linked to subtle differences in foraging activity between distinct hives. The implications of these results are discussed in terms of potential short-term and long-term consequences of disturbed foraging ability triggered by exaggerated exposure to sublethal doses of crop protection chemicals, and its potential impact on colony health.

  4. Effects of Sublethal Cadmium Exposure on Antipredator Behavioural and Antitoxic Responses in the Invasive Amphipod Dikerogammarus villosus

    Science.gov (United States)

    Sornom, Pascal; Gismondi, Eric; Vellinger, Céline; Devin, Simon; Férard, Jean-François; Beisel, Jean-Nicolas

    2012-01-01

    Amphipods are recognised as an important component of freshwater ecosystems and are frequently used as an ecotoxicological test species. Despite this double interest, there is still a lack of information concerning toxic impacts on ecologically relevant behaviours. The present study investigated the influence of cadmium (Cd), a non-essential heavy metal, on both antipredator behaviours and antitoxic responses in the invasive amphipod Dikerogammarus villosus under laboratory conditions. Amphipod behaviour (i.e. refuge use, aggregation with conspecifics, exploration and mobility) was recorded following a 4-min test-exposure to 500 µg Cd/L with or without a 24-h Cd pre-exposure and in the presence or absence of a high perceived risk of predation (i.e. water scented by fish predators and injured conspecifics). Following behavioural tests, malondialdehyde (MDA) levels, a biomarker for toxic effect, and energy reserves (i.e. lipid and glycogen contents) were assessed. Cd exposures induced (1) cell damage reflected by high MDA levels, (2) erratic behaviour quantified by decreasing refuge use and exploration, and increasing mobility, and (3) a depletion in energy reserves. No significant differences were observed between 4-min test-exposed and 24-h pre-exposed individuals. Gammarids exposed to Cd had a disturbed perception of the alarm stimuli, reflected by increased time spent outside of refuges and higher mobility compared to gammarids exposed to unpolluted water. Our results suggest that Cd exposure rapidly disrupts the normal behavioural responses of gammarids to alarm substances and alters predator-avoidance strategies, which could have potential impacts on aquatic communities. PMID:22879985

  5. Effects of sublethal cadmium exposure on antipredator behavioural and antitoxic responses in the invasive amphipod Dikerogammarus villosus.

    Directory of Open Access Journals (Sweden)

    Pascal Sornom

    Full Text Available Amphipods are recognised as an important component of freshwater ecosystems and are frequently used as an ecotoxicological test species. Despite this double interest, there is still a lack of information concerning toxic impacts on ecologically relevant behaviours. The present study investigated the influence of cadmium (Cd, a non-essential heavy metal, on both antipredator behaviours and antitoxic responses in the invasive amphipod Dikerogammarus villosus under laboratory conditions. Amphipod behaviour (i.e. refuge use, aggregation with conspecifics, exploration and mobility was recorded following a 4-min test-exposure to 500 µg Cd/L with or without a 24-h Cd pre-exposure and in the presence or absence of a high perceived risk of predation (i.e. water scented by fish predators and injured conspecifics. Following behavioural tests, malondialdehyde (MDA levels, a biomarker for toxic effect, and energy reserves (i.e. lipid and glycogen contents were assessed. Cd exposures induced (1 cell damage reflected by high MDA levels, (2 erratic behaviour quantified by decreasing refuge use and exploration, and increasing mobility, and (3 a depletion in energy reserves. No significant differences were observed between 4-min test-exposed and 24-h pre-exposed individuals. Gammarids exposed to Cd had a disturbed perception of the alarm stimuli, reflected by increased time spent outside of refuges and higher mobility compared to gammarids exposed to unpolluted water. Our results suggest that Cd exposure rapidly disrupts the normal behavioural responses of gammarids to alarm substances and alters predator-avoidance strategies, which could have potential impacts on aquatic communities.

  6. Interactions between Zooplankton and Crude Oil: Toxic Effects and Bioaccumulation of Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Almeda, Rodrigo; Wambaugh, Zoe; Wang, Zucheng; Hyatt, Cammie; Liu, Zhanfei; Buskey, Edward J.

    2013-01-01

    We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1) the effects of crude oil (Louisiana light sweet oil) on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in mesozooplankton communities, (2) the lethal effects of dispersant (Corexit 9500A) and dispersant-treated oil on mesozooplankton, (3) the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4) the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L−1 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1∶20), dispersant (0.25 µl L−1) and dispersant- treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 µl L−1) to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments. PMID:23840628

  7. Interactions between zooplankton and crude oil: toxic effects and bioaccumulation of polycyclic aromatic hydrocarbons.

    Directory of Open Access Journals (Sweden)

    Rodrigo Almeda

    Full Text Available We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1 the effects of crude oil (Louisiana light sweet oil on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs in mesozooplankton communities, (2 the lethal effects of dispersant (Corexit 9500A and dispersant-treated oil on mesozooplankton, (3 the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4 the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L(-1 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1∶20, dispersant (0.25 µl L(-1 and dispersant-treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 µl L(-1 to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments.

  8. Chronic Sublethal Effects of San Francisco Bay Sediments on Nereis (Neanthes) arenaceodentata; Interpretative Guidance for a Growth End Point

    Science.gov (United States)

    1993-09-01

    experimentally. Once nereid eggs begin developing in the coelom , secretion of a separate tropic hormone initiates vitellogenesis (Baskin 1976). In N...Material Management in San Francisco Bay .............................. 2 Overview of Sediment Toxicity Test Development in the United States...Material in San Francisco Bay ......................... 3 Table 2. Milestones in Scientific Development of Sediment Toxicity Tests

  9. Intra- and intergenerational persistence of an insect nucleopolyhedrovirus: adverse effects of sublethal disease on host development, reproduction, and susceptibility to superinfection.

    Science.gov (United States)

    Cabodevilla, Oihana; Villar, Eduardo; Virto, Cristina; Murillo, Rosa; Williams, Trevor; Caballero, Primitivo

    2011-05-01

    Sublethal infections by Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) are common in field populations of the beet armyworm (S. exigua, Hübner) in the Almerian horticultural region of Spain. Inoculation of second, third, and fourth instars with occlusion bodies (OBs) of an isolate (VT-SeAl1) associated with vertically transmitted infections resulted in 15 to 100% of sublethal infection in adult survivors, as determined by reverse transcription-PCR (RT-PCR) detection of viral DNA polymerase transcripts, and quantitative PCR (qPCR) targeted at the DNA polymerase gene. The prevalence of adult sublethal infection was positively related to the inoculum OB concentration consumed during the larval stage. Sublethal infections persisted in OB-treated insects for at least five generations. Viral transcripts were more frequently detected in adult insects than in third instars. qPCR analysis indicated a consistently higher prevalence of sublethal infection than RT-PCR. Sublethal infection was associated with significant reductions in pupal weight, adult emergence, fecundity, and fertility (egg hatch) and significant increases in larval development time and duration of the preoviposition period. Insects taken from a persistently infected experimental population were significantly more susceptible to the OB inoculum than control insects that originated from the same virus-free colony as the persistently infected insects. We conclude that OB treatment results in rapid establishment of sublethal infections that persist between generations and which incur costs in the development and reproductive capacity of the host insect.

  10. Mercury toxicity and neurodegenerative effects.

    Science.gov (United States)

    Carocci, Alessia; Rovito, Nicola; Sinicropi, Maria Stefania; Genchi, Giuseppe

    2014-01-01

    Mercury is among the most toxic heavy metals and has no known physiological role in humans. Three forms of mercury exist: elemental, inorganic and organic. Mercury has been used by man since ancient times. Among the earliest were the Chinese and Romans, who employed cinnabar (mercury sulfide) as a red dye in ink (Clarkson et al. 2007). Mercury has also been used to purify gold and silver minerals by forming amalgams. This is a hazardous practice, but is still widespread in Brazil's Amazon basin, in Laos and in Venezuela, where tens of thousands of miners are engaged in local mining activities to find and purify gold or silver. Mercury compounds were long used to treat syphilis and the element is still used as an antiseptic,as a medicinal preservative and as a fungicide. Dental amalgams, which contain about 50% mercury, have been used to repair dental caries in the U.S. since 1856.Mercury still exists in many common household products around the world.Examples are: thermometers, barometers, batteries, and light bulbs (Swain et al.2007). In small amounts, some organo mercury-compounds (e.g., ethylmercury tiosalicylate(thimerosal) and phenylmercury nitrate) are used as preservatives in some medicines and vaccines (Ballet al. 2001).Each mercury form has its own toxicity profile. Exposure to Hg0 vapor and MeHg produce symptoms in CNS, whereas, the kidney is the target organ when exposures to the mono- and di-valent salts of mercury (Hg+ and Hg++, respectively)occur. Chronic exposure to inorganic mercury produces stomatitis, erethism and tremors. Chronic MeHg exposure induced symptoms similar to those observed in ALS, such as the early onset of hind limb weakness (Johnson and Atchison 2009).Among the organic mercury compounds, MeHg is the most biologically available and toxic (Scheuhammer et a!. 2007). MeHg is neurotoxic, reaching high levels of accumulation in the CNS; it can impair physiological function by disrupting endocrine glands (Tan et a!. 2009).The most

  11. [Repair mechanism of frozen sublethally damaged Staphylococcus aureus].

    Science.gov (United States)

    Huang, Zhongmin; Lv, Haipeng; Ai, Zhilu; Wang, Na; Xie, Xinhua; Fan, Huiping; Pan, Zhili; Suo, Biao

    2015-11-04

    To study the repair mechanisms of frozen sublethally damaged Staphylococcus aurous cells. We resuscitated frozen sublethally damaged S. aureus at 37 degrees C for different time within 3 h. Meanwhile, we compared the morphological changes of the frozen sublethally damaged cells after 1 h of resuscitation using transmission electron microscopy assay (TEM). The expressions of the transcriptional attenuator MsrR (msrR), iron (Fe3+) ABC transporter ATP-binding protein (fhuC), and cytochrome b (cytB) genes were quantitatively analyzed by real-time fluorescence quantitative PCR (Real-time PCR) method. The content of cells outside leakage, active oxygen (ROS), and superoxide dismutase (SOD) activity were also determined by ultraviolet spectrophotometry. More than 99% of the frozen sublethally damaged S. aureus repaired after 3 h. The resuscitated cells expressed an equal resistance to high concentration of NaCl. Real-time PCR results showed that the msrR and fhuC genes expressions were down-regulated, whereas the cytB gene expression was up-regulated significantly. The frozen sublethally damaged S. aureus cellar surface ultrastructure significant changed during resuscitation. The cell surface became compact and sturdy from smooth and transparent. The cell leakage rate of ultraviolet absorption material gradually decreased. Meanwhile, the intracellular ROS level declined along with the decrease of SOD activity. Frozen sublethally damaged cells may regain the capability of resistance to high salt stress by repairing cell membrane integrity, reducing the content of ROS through gene regulation, inhibiting the toxicity of active oxygen to the cells. Meanwhile, the regulation of metabolism related genes (cytB) provides the energy for the requirement of cells, therefore, the frozen sublethally damaged cells were repaired finally.

  12. DETECTION OF THERMAL SUBLETHAL INJURY IN ESCHERICHIA COLI VIA THE SELECTIVE MEDIUM PLATING TECHNIQUE: MECHANISMS AND IMPROVEMENTS

    Directory of Open Access Journals (Sweden)

    Laura Espina

    2016-08-01

    Full Text Available In food preservation, the selective medium plating technique (SMPT is commonly used in order to detect and quantify the amount of sublethally injured cells in their bacterial cytoplasmic membranes after inimical treatments. From an applicative point of view, this information is of use in the synergistic combination of different preservation technologies, so that cells that are sublethally injured after one or more processes can end up being entirely inactivated by other hurdle(s. However, little work has been done to explain the reasons for the inability of sublethally injured cells to outgrow in selective agar media (containing the osmolyte NaCl as a selective agent, whereas they are able to grow in non-selective agar media. This research could contribute to explain this technique’s limits. In the present paper, the performance of SMPT on Escherichia coli cells after heat treatments is explored by applying different selective agents in the recovery media, using several mutants lacking factors involved in osmoregulation, and also by examining the integrity of the cytoplasmic membrane. In view of the results, the possibility of a specific toxic effect of Na+ as the main mechanism under SMPT is discarded, and the same level of sublethal injury is detected using KCl instead of NaCl. The synthesis of the osmoprotectant trehalose determined the maximum osmotolerance of intact cells to the selective agents, but was not crucial in the quantification of sublethal injury. Moreover, the extent of sublethal injury detected via SMPT was directly correlated with the physical loss of integrity of the cell membrane as measured with the propidium iodide-exclusion technique when that dye was added before thermal treatments. The present work confirms the adequacy of SMPT as a tool for detecting the occurrence and quantity of sublethally injured cells and thus, for efficiently designing combined preservation treatments. Additionally, we propose the combination

  13. Chronic Sublethal Effects of San Francisco Bay Sediments on Nereis (Neanthes) arenaceodentata; Effect of Food Ration on Sediment Toxicity

    Science.gov (United States)

    1993-09-01

    Juvenile worms grow, and eggs become visible in the coelom of females about 6 weeks postemergence. Egg deposition fol- lows 3 to 7 weeks later. The entire...paired using the fighting response (Reish and Alosi 1968) and the presence or absence of eggs in the coelom . Unpaired worms were discarded. Pairs were...presence of eggs in the coelom and the fighting reaction described by Reish and Alosi (1968). Mated pairs were placed in 600-ml beakers covered with

  14. Sublethal effects of the organic antifoulant Mexel(R)432 on osmoregulation and xenobiotic detoxification in the flatfish Solea senegalensis.

    Science.gov (United States)

    López-Galindo, Cristina; Vargas-Chacoff, Luis; Nebot, Enrique; Casanueva, José F; Rubio, Daniel; Solé, Montserrat; Mancera, Juan Miguel

    2010-03-01

    Mexel(R)432 is an anionic surfactant used as biocide in the cooling water system of power plants for biofouling reduction. Refrigeration waters from power plants do not usually follow, prior to their discharge to sea, any treatment aimed to eliminate biocides and this can have negative consequences on the aquatic fauna nearby. The effects of different concentrations of the antifoulant Mexel(R)432 (0.5, 1 and 2mgL(-1)) on osmoregulation (osmolality and Na(+)/K(+)-ATPase activity) and stress parameters (cortisol, glucose, and lactate) were assessed in juveniles of the flatfish Solea senegalensis. Gill histopathology and alterations due to oxidative stress (increased lipid peroxidation, LPO, levels) at branchial and hepatic levels were also considered. Other parameters tested were the antioxidant enzymes (catalase, CAT; glutathione peroxidase, GPX; and glutathione reductase, GR), xenobiotic metabolism defenses involved in detoxification (carboxylesterase, CbE; 7-ethoxyresorufin O-deethylase, EROD; and glutathione S-transferase, GST) and the neurotransmitter acetylcholinesterase (AChE) activity. Significant variations in osmoregulatory parameters, histological lesions and decreased branchial Na(+)/K(+)-ATPase activity were observed in exposed fish. Other gill biomarkers presented little or no significant variations in relation to controls. In contrast, hepatic parameters, such as CAT activity, were inhibited while EROD activity was initially elevated but after longer exposures it recovered basal values. These results suggested that under our experimental protocol exists toxic associated to Mexel(R)432 exposures. Copyright 2009 Elsevier Ltd. All rights reserved.

  15. Sublethal effects of copper nanoparticles on the histology of gill, liver and kidney of the Caspian roach, Rutilus rutilus caspicus

    Directory of Open Access Journals (Sweden)

    Sh. Aghamirkarimi

    2017-09-01

    Full Text Available The current study has determined the toxicity effects of copper nanoparticles on the some vital organs such as gill, liver and kidney of Caspian Roach; Rutillus rutillus caspicus. For this purpose, 120 fishes were used as experimental samples and exposed to 0.1, 0.2 and 0.5 mg/L of Cu nanoparticles for 21 days, and 30 fishes assumed as the experiment control. The mean water temperature of the aquaria was 22±2 ºC, dissolved oxygen 5.2 mg/L, pH at 7±0.004 and the concentration of calcium carbonate was 270 ppm. On 7, 14 and 21 days after exposing the fishes to copper nanoparticles, three fishes were randomly selected from each aquaria, sacrificed and samples from their gill, liver and kidney were taken and fixed in cold 10 % buffered formalin. Then microscopic sections were prepared and examined by light microscope which showed histological alternations in the gill, liver and kidney tissues. Evaluation of these changes could be useful in estimating the harmful effects of copper nanoparticles. Histological alternation in gills included: hyperplasia, fusion and detachment of secondary lamellae, blood congestion in vascular axis of primary filaments, reduced secondary lamellae length and cellular degeneration. Histological changes in liver included blood congestion in the central veins, cytoplasmic vacuolation of the hepatocytes, cellular degeneration and congestion in the blood sinusoids and necrosis of the hepatocytes. Histological changes in kidneys included glomerular shrinkage, severe degeneration in the tubules cells, interstitial tissue and glomerulus, increase in interstitial tissue cells and macrophages aggregation. The degree of damages was more intensive at higher copper nanoparticles concentrations. The result of the study showed that copper nanoparticles could cause severe damages in the vital tissues of Caspian roach; Rutillus rutillus caspicus and have lethal effects for fish.

  16. Cholinergic System Under Aluminium Toxicity in Rat Brain

    OpenAIRE

    Yellamma, K.; Saraswathamma, S.; Kumari, B. Nirmala

    2010-01-01

    The present investigation envisages the toxic effects of aluminium on the cholinergic system of male albino rat brain. Aluminium toxicity (LD50/24 h) evaluated as per Probit method was found to be 700 mg/kg body weight. One-fifth of lethal dose was taken as the sublethal dose. For acute dose studies, rats were given a single lethal dose of aluminium acetate orally for one day only and for chronic dose studies, the rats were administered with sublethal dose of aluminium acetate once in a day f...

  17. Toxicity and antinociceptive effects of Hamelia patens

    Directory of Open Access Journals (Sweden)

    Angel Josabad Alonso-Castro

    Full Text Available Abstract Many medicinal herbs are used in folk medicine without taking into account their toxicity. Hamelia patens Jacq. (Rubiaceae, a Mexican endemic species, is used for the empirical treatment of pain. The aim of this work was to evaluate the toxicity and antinociceptive effects of ethanolic extracts of H. patens leaves. The toxicity of H. patens leaves (500–5000 mg/kg was evaluated in acute (14 days and subacute (28 days assays. In the subacute assay, a blood analysis (both hematology and chemistry was carried out. The antinociceptive effects of H. patens leaves (50–200 mg/kg were evaluated using thermal-induced nociception (hot plate and the chemical-induced nociceptive tests (acid acetic and formalin. In the acute toxicity test, the LD50 estimated for H. patens leaves was 2964 mg/kg i.p. and >5000 mg/kg p.o., whereas in the subacute test HPE did not affect hematological or biochemical parameters. In chemical-induced nociception models, H. patens (100 and 200 mg/kg p.o. showed antinociceptive effects with similar activity than 100 mg/kg naproxen. In the hot plate test, HPE at 100 mg/kg (17% and 200 mg/kg (25% showed moderate antinociceptive effects. HPE could be a good source of antinociceptive agents because of its good activity and low toxicity.

  18. Multibiomarker assessment of cerium dioxide nanoparticle (nCeO2) sublethal effects on two freshwater invertebrates, Dreissena polymorpha and Gammarus roeseli.

    Science.gov (United States)

    Garaud, M; Trapp, J; Devin, S; Cossu-Leguille, C; Pain-Devin, S; Felten, V; Giamberini, L

    2015-01-01

    Cerium nanoparticles (nCeO2) are widely used in everyday products, as fuel and paint additives. Meanwhile, very few studies on nCeO2 sublethal effects on aquatic organisms are available. We tried to fill this knowledge gap by investigating short-term effects of nCeO2 at environmentally realistic concentrations on two freshwater invertebrates; the amphipod Gammarus roeseli and the bivalve Dreissena polymorpha, using an integrated multibiomarker approach to detect early adverse effects of nCeO2 on organism biology. Differences in the behaviour of the organisms and of nanoparticles in the water column led to differential nCeO2 bioaccumulations, G. roeseli accumulating more cerium than D. polymorpha. Exposure to nCeO2 led to decreases in the size of the lysosomal system, catalase activity and lipoperoxidation in mussel digestive glands that could result from nCeO2 antioxidant properties, but also negatively impacted haemolymph ion concentrations. At the same time, no strong adverse effects of nCeO2 could be observed on G. roeseli. Further experiments will be necessary to confirm the absence of severe nCeO2 adverse effects in long-term environmentally realistic conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Novel pathways for injury from offshore oil spills: direct, sublethal and indirect effects of the Deepwater Horizon oil spill on pelagic Sargassum communities.

    Directory of Open Access Journals (Sweden)

    Sean P Powers

    Full Text Available The pelagic brown alga Sargassum forms an oasis of biodiversity and productivity in an otherwise featureless ocean surface. The vast pool of oil resulting from the Deepwater Horizon oil spill came into contact with a large portion of the Gulf of Mexico's floating Sargassum mats. Aerial surveys performed during and after the oil spill show compelling evidence of loss and subsequent recovery of Sargassum. Expanding on the trends observed in the aerial surveys, we conducted a series of mesocosm experiments to test the effect of oil and dispersants on the vertical position and weight of the Sargassum complex (Sargassum natans and S. fluitans, as well as on the dissolved oxygen concentrations surrounding the algae. Dispersant and dispersed-oil had significant effects on the vertical position of both species of Sargassum over a period of 72 hours. Similarly, dissolved oxygen concentrations were lowest in dispersant and dispersed-oil treatments, respectively. Cumulatively, our findings suggest three pathways for oil-spill related injury: (1 Sargassum accumulated oil on the surface exposing animals to high concentrations of contaminants; (2 application of dispersant sank Sargassum, thus removing the habitat and potentially transporting oil and dispersant vertically; and (3 low oxygen surrounded the habitat potentially stressing animals that reside in the alga. These pathways represent direct, sublethal, and indirect effects of oil and dispersant release that minimize the ecosystem services provided by floating Sargassum - the latter two effects are rarely considered in assessing impacts of oil spills or response procedures.

  20. Novel pathways for injury from offshore oil spills: direct, sublethal and indirect effects of the Deepwater Horizon oil spill on pelagic Sargassum communities.

    Science.gov (United States)

    Powers, Sean P; Hernandez, Frank J; Condon, Robert H; Drymon, J Marcus; Free, Christopher M

    2013-01-01

    The pelagic brown alga Sargassum forms an oasis of biodiversity and productivity in an otherwise featureless ocean surface. The vast pool of oil resulting from the Deepwater Horizon oil spill came into contact with a large portion of the Gulf of Mexico's floating Sargassum mats. Aerial surveys performed during and after the oil spill show compelling evidence of loss and subsequent recovery of Sargassum. Expanding on the trends observed in the aerial surveys, we conducted a series of mesocosm experiments to test the effect of oil and dispersants on the vertical position and weight of the Sargassum complex (Sargassum natans and S. fluitans), as well as on the dissolved oxygen concentrations surrounding the algae. Dispersant and dispersed-oil had significant effects on the vertical position of both species of Sargassum over a period of 72 hours. Similarly, dissolved oxygen concentrations were lowest in dispersant and dispersed-oil treatments, respectively. Cumulatively, our findings suggest three pathways for oil-spill related injury: (1) Sargassum accumulated oil on the surface exposing animals to high concentrations of contaminants; (2) application of dispersant sank Sargassum, thus removing the habitat and potentially transporting oil and dispersant vertically; and (3) low oxygen surrounded the habitat potentially stressing animals that reside in the alga. These pathways represent direct, sublethal, and indirect effects of oil and dispersant release that minimize the ecosystem services provided by floating Sargassum - the latter two effects are rarely considered in assessing impacts of oil spills or response procedures.

  1. Toxicity of Nanomaterials-Physicochemical Effects

    Directory of Open Access Journals (Sweden)

    A Rahi

    2015-02-01

    Full Text Available Nanomaterials involve the structures with at least one dimension of <100 nm. Recently, development in nanotechnology has led to the use of nanomaterials in many different fields. On the other hand, increasing use of nanomaterials has resulted in release of these materials to the environment. Therefore, before employing these materials in biological and living systems, they should be evaluated in terms of biocompatibility and distribution. Although the toxic effects of nanomaterials on living organisms, human health and the environment have been studied by some researchers, there are too much uncertainty regarding the effects and mechanisms of toxicity of nanomaterials. Therefore, understanding the toxicity effects of nanomaterials is highly desirable. Cellular uptake mechanisms and dispersion of nanomaterials in biological environments depend on their physicochemical properties. Therefore, knowledge of the unique characteristics of nanomaterials and the interactions of nanomaterials with biological systems, are important criteria for the safe use of nanomaterials. Properties of nanomaterials such as size, shape, aspect ratio, density, surface and structural defects and dissolving rate are the main causes of cytotoxicity and side effects of these materials in the body. Exposure to nanomaterials may cause a range of acute and chronic effects, including inflammation, exacerbation of asthma, metal fume fever, fibrosis, chronic inflammatory diseases and cancer. The present paper, reviews the previous studies aiming at the investigation of the relation between the physiochemical properties of nanomaterials and their toxicity.

  2. Effects of Sublethal Cadmium Exposure on Antipredator Behavioural and Antitoxic Responses in the Invasive Amphipod Dikerogammarus villosus

    OpenAIRE

    Pascal Sornom; Eric Gismondi; Céline Vellinger; Simon Devin; Jean-François Férard; Jean-Nicolas Beisel

    2012-01-01

    Amphipods are recognised as an important component of freshwater ecosystems and are frequently used as an ecotoxicological test species. Despite this double interest, there is still a lack of information concerning toxic impacts on ecologically relevant behaviours. The present study investigated the influence of cadmium (Cd), a non-essential heavy metal, on both antipredator behaviours and antitoxic responses in the invasive amphipod Dikerogammarus villosus under laboratory conditions. Amphip...

  3. Rearing effect of biofloc on antioxidant and antimicrobial transcriptional response in Litopenaeus stylirostris shrimp facing an experimental sub-lethal hydrogen peroxide stress.

    Science.gov (United States)

    Cardona, Emilie; Saulnier, Denis; Lorgeoux, Bénédicte; Chim, Liet; Gueguen, Yannick

    2015-08-01

    This study compares the antioxidant and antimicrobial transcriptional expression of blue shrimps reared according to two different systems, BioFloc Technology (BFT) and Clear sea Water (CW) and their differential responses when facing an experimental sublethal hydrogen peroxide stress. After 30 days of rearing, juvenile shrimps were exposed to H2O2 stress at a concentration of 30 ppm during 6 h. The oxidative stress caused by H2O2 was examined in the digestive glands of the shrimp, in which antioxidant enzyme (AOE) and antimicrobial peptide (AMP) gene expression were analysed by quantitative real-time PCR. Results showed that rearing conditions did not affect the expression of genes encoding AOEs or AMPs. However, H2O2 stress induced a differential response in expression between shrimps from the two rearing treatments (BFT and CW). Comparative analysis of the expression profiles indicates that catalase transcripts were significantly upregulated by H2O2 stress for BFT shrimps while no change was observed for CW shrimps. In contrast, H2O2 caused down-regulation of superoxide dismutase and glutathione transferase transcripts and of the three AMP transcripts studied (penaeidin 2 and 3, and crustin) for CW shrimps, while no effect was observed on BFT shrimp transcript levels. These results suggested that BFT shrimps maintained antioxidant and AMP responses after stress and therefore can effectively protect their cells against oxidative stress, while CW shrimp immune competence seems to decrease after stress. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Effects of chronic exposure to sublethal concentrations of lead acetate on heme synthesis and immune function in red-tailed hawks.

    Science.gov (United States)

    Redig, P T; Lawler, E M; Schwartz, S; Dunnette, J L; Stephenson, B; Duke, G E

    1991-07-01

    Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks. Alterations in the heme biosynthetic pathway were demonstrated after the first week of exposure to 0.82 mg lead per kilogram body weight per day. Activity of erythrocyte porphobilinogen synthase (aminolevulinic acid dehydratase) was depressed significantly and did not return to normal levels until 5 weeks after the termination of lead treatments. A rapid and relatively brief increase in erythrocyte free protoporphyrin and a slower but more prolonged increase in its zinc complex were also demonstrated with exposure to this dose of lead for 3 weeks. Less substantial decreases in hematocrit and hemoglobin levels occurred but only in the longer experiment with exposure to higher lead levels. Short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes. Increased lead exposure produced a significant decrease in the mitogenic response but had no effect on antibody titers.

  5. Sublethal effects of diazinon, fenitrothion and chlorpyrifos on the functional response of predatory bug, Andrallus spinidens Fabricius (Hem.: Pentatomidae in the laboratory conditions

    Directory of Open Access Journals (Sweden)

    Moloud GholamzadehChitgar

    2014-04-01

    Full Text Available The sublethal effects of diazinon, fenitrothion and chlorpyrifos on the functional response of predatory bug, Andrallus spinidens Fabricius (Hem.: Pentatomidae, a potential biological control agent, were studied on 5th-instar nymphs. The experiment was conducted in varying densities (2, 4, 8, 16, 32 and 64 of last instars larvae of Chilo suppressalis Walker (Lepidoptera: Pyralidae as prey at 25 ± 2 °C, 60% ± 10% relative humidity (RH and a photoperiod of 16:8 h (L: D. The results of logistic regressions revealed a type II functional response in the control and all insecticide treatments. Comparison of functional response curves revealed that tested insecticides markedly decreased the mean of preys consumed by A. spinidens. Among them, functional response curve of A. spinidens in chlorpyrifos treatment was significantly lower than the other treatments. In this study, application of insecticides caused a decrease in the attack rate and an increase in the handling time of exposed bugs compared with the control. The longest handling time (3.97 ± 0.62 and the lowest attack rate (0.023 ± 0.007 were observed in chlorpyrifos and fenitrothion treatments, respectively. The results suggested that the adverse effect of these insecticides on A. spinidens should be considered in integrated pest management programs (IPM.

  6. Age Stage Two-Sex Life Table Reveals Sublethal Effects of Some Herbal and Chemical Insecticides on Adults of Bemisia tabaci (Hem.: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-01-01

    Full Text Available The sweetpotato whitefly, Bemisia tabaci (Genn. (Hem.: Aleyrodidae, is an important pest of agriculture in subtropical and tropical areas. In this study, we used the age-stage two-sex life table to evaluate the sublethal effects of the herbal extracts taken from Fumaria parviflora Lam. (Fumariaceae, Teucrium polium L. (Lamiaceae, Calotropis procera (Willd. R. Br. (Asclepiadaceae, and Thymus vulgaris L. (Lamiaceae as well as the two commercial synthetic insecticides, pymetrozin and neemarin. The whiteflies were exposed to each insecticide using leaf-dip method. Analysis of life table parameters revealed significant differences (P≤0.05 in the net reproductive rate (R0, NRR, intrinsic rate of increase (rm, and finite rate of increase (λ among different insecticides. The lowest values of the three population parameters, R0, r, and λ, were observed on whiteflies treated with pymetrozin (2.455, 0.036, and 1.036, T. polium (2.828, 0.044, and 1.045, and neemarin (2.998, 0.046, and 1.047, respectively. Results of this study highlights the satisfactory insecticidal effects of the extract taken from T. polium on B. tabaci, which is comparable to the two commonly used synthetic insecticides.

  7. Toxicokinetic-toxicodynamic modeling of quantal and graded sublethal endpoints: a brief discussion of concepts

    NARCIS (Netherlands)

    Ashauer, R.; Agatz, A.; Albert, C.; Ducrot, V.; Galic, N.G.; Hendriks, J.; Jager, T.; Kretschmann, A.; O'Connor, I.; Rubach, M.N.; Nyman, M.; Schmitt, W.; Stadnicka, J.; Brink, van den P.J.

    2011-01-01

    We report on the advantages and problems of using toxicokinetic-toxicodynamic (TKTD) models for the analysis, understanding, and simulation of sublethal effects. Only a few toxicodynamic approaches for sublethal effects are available. These differ in their effect mechanism and emphasis on linkages

  8. Lethal and sub-lethal effects of commonly used anti-sea lice formulations on non-target crab Metacarcinus edwardsii larvae.

    Science.gov (United States)

    Gebauer, Paulina; Paschke, Kurt; Vera, Claudia; Toro, Jorge E; Pardo, Miguel; Urbina, Mauricio

    2017-10-01

    The pesticides used by the salmon industry to treat sea lice, are applied in situ via a bath solution and are subsequently discharged into the surrounding medium. The effects of cypermethrin, deltamethrin, azamethiphos and hydrogen peroxide were assessed on the performance of Metacarcinus edwardsii larvae, an important crab for Chilean fishery. All larvae were dead or dying after 30 min of exposure to cypermethrin and after 40 min to deltamethrin at concentrations 100 and 20 times lower (0.15 and 0.1 μg L-1, respectively) than the concentrations and exposure times recommended by the manufacturers (CRM) to treat sea lice. Azamethiphos affected all larvae at a concentration 10 times lower than CRM. Hydrogen peroxide had the lowest detrimental effects, but at the CRM, 100% of the larvae were affected. Sub-lethal effects, i.e prolonged developmental time, were observed at concentrations lower than CRM. Repeated exposure to azamethiphos (0.0625-0.5 μg L-1) and hydrogen peroxide (188-1500 mg L-1) had effects on survival. In conclusion, the pesticides used against parasitic copepod tested here, negatively affect non-target crustacean larvae. Due to the product's characteristics, the lethal effects of the pyrethroids probably are restricted to the time and area of application, while the action of azamethiphos may extend to a wider area. Current data are insufficient to accurately dimension the effects of these compounds in the field. More research is required to evaluate the consequences of prolonged developmental times and/or reduction in appendage mobility, so as the effects of these compounds on the pelagic and benthic communities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Multibiomarker assessment of cerium dioxide nanoparticle (nCeO{sub 2}) sublethal effects on two freshwater invertebrates, Dreissena polymorpha and Gammarus roeseli

    Energy Technology Data Exchange (ETDEWEB)

    Garaud, M. [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); International Consortium for the Environmental Implications of Nanotechnology (iCEINT), Aix en Provence (France); Trapp, J.; Devin, S.; Cossu-Leguille, C.; Pain-Devin, S.; Felten, V. [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); Giamberini, L., E-mail: laure.giamberini@univ-lorraine.fr [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); International Consortium for the Environmental Implications of Nanotechnology (iCEINT), Aix en Provence (France)

    2015-01-15

    Highlights: • Gammarids and mussels both accumulated significant amount of waterborne nCeO{sub 2}. • nCeO{sub 2} decreased catalase, lysosomal system size and lipoperoxidation in mussels. • nCeO{sub 2} could exert antioxidant protecting activity in mussels. • In contrast with mussels, no effects of nCeO{sub 2} were observed on Gammarids. - Abstract: Cerium nanoparticles (nCeO{sub 2}) are widely used in everyday products, as fuel and paint additives. Meanwhile, very few studies on nCeO{sub 2} sublethal effects on aquatic organisms are available. We tried to fill this knowledge gap by investigating short-term effects of nCeO{sub 2} at environmentally realistic concentrations on two freshwater invertebrates; the amphipod Gammarus roeseli and the bivalve Dreissena polymorpha, using an integrated multibiomarker approach to detect early adverse effects of nCeO{sub 2} on organism biology. Differences in the behaviour of the organisms and of nanoparticles in the water column led to differential nCeO{sub 2} bioaccumulations, G. roeseli accumulating more cerium than D. polymorpha. Exposure to nCeO{sub 2} led to decreases in the size of the lysosomal system, catalase activity and lipoperoxidation in mussel digestive glands that could result from nCeO{sub 2} antioxidant properties, but also negatively impacted haemolymph ion concentrations. At the same time, no strong adverse effects of nCeO{sub 2} could be observed on G. roeseli. Further experiments will be necessary to confirm the absence of severe nCeO{sub 2} adverse effects in long-term environmentally realistic conditions.

  10. Development and application of long-term sublethal whole sediment tests with Arenicola marina and Corophium volutator using Ivermectin as the test compound

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Yvonne T. [Centre for Environment, Fisheries and Aquaculture Science, Burnham Laboratory, Remembrance Avenue, Burnham-on-Crouch, Essex, CM0 8HA (United Kingdom)]. E-mail: yvonne.allen@cefas.co.uk; Thain, John E. [Centre for Environment, Fisheries and Aquaculture Science, Burnham Laboratory, Remembrance Avenue, Burnham-on-Crouch, Essex, CM0 8HA (United Kingdom); Haworth, Sarah [Centre for Environment, Fisheries and Aquaculture Science, Burnham Laboratory, Remembrance Avenue, Burnham-on-Crouch, Essex, CM0 8HA (United Kingdom); Barry, Jon [Centre for Environment, Fisheries and Aquaculture Science, Burnham Laboratory, Remembrance Avenue, Burnham-on-Crouch, Essex, CM0 8HA (United Kingdom)

    2007-03-15

    Short-term whole sediment tests using the amphipod Corophium volutator and the polychaete Arenicola marina are now routinely used in Europe to assess the acute toxicity of marine sediments. However, there is still a need to develop longer-term assays which measure effects on sublethal endpoints that are more relevant to predicting impacts at the population level. The effect of increasing exposure times and measuring additional endpoints such as growth, on the sensitivity of these assays was investigated. The test compound used was the chemotherapeutant Ivermectin (IVM), used in aquaculture to treat sea lice infestations. IVM was found to be acutely toxic to both test organisms. Extending the lugworm test to 100 days increased sensitivity of survival by a factor of three; a significant reduction in casting rate was observed at concentrations an order of magnitude lower. This assay shows potential for detecting the sublethal effects of low concentrations of sediment contaminants. Increasing the exposure time did not seem to affect the sensitivity of the amphipod, but further method development is required. - Long-term sublethal sediment tests are more sensitive than standard acute tests when assessing the toxic effects of Ivermectin.

  11. The use of bacteria for detecting toxic effects of pollutants in soil and water

    Science.gov (United States)

    Obiakor, Maximilian; Wilson, Susan; Tighe, Matthew; Pereg, Lily

    2017-04-01

    Microbial abundance and diversity are essential for sustaining soil structure and function and have been strongly linked to human health and wellbeing. Antimony (Sb) in the environment can present an ecological hazard and depending on concentration can be lethal. The toxic effects of Sb(III) and Sb(V) on the model soil bacterium Azospirillum brasilense Sp7 were assessed in exposure-dose-response assays and water samples from an Sb contaminated creek were analyzed for bacterial mortality. In both cases, Sb(III) and Sb(V) greatly affected the survival of A. brasilense Sp7 cells. The Sb(III) had a greater toxic effect than Sb(V) at all concentrations tested. Critical concentrations of Sb also caused variant colonies to appear, indicating both acute and sub-lethal effects, which were dose and time dependent. This work demonstrates the usefulness of A. brasilense as an indicator species to detect harmful effects of an environmental pollutant of emerging concern.

  12. Sub-lethal effects of water-based drilling muds on the deep-water sponge Geodia barretti.

    Science.gov (United States)

    Edge, Katelyn J; Johnston, Emma L; Dafforn, Katherine A; Simpson, Stuart L; Kutti, Tina; Bannister, Raymond J

    2016-05-01

    Offshore oil and gas activities can result in the discharge of large amounts of drilling muds. While these materials have generally been regarded as non-toxic to marine organisms, recent studies have demonstrated negative impacts to suspension feeding organisms. We exposed the arctic-boreal sponge Geodia barretti to the primary particulate components of two water-based drilling muds; barite and bentonite. Sponges were exposed to barite, bentonite and a natural reference sediment at a range of total suspended solid concentrations (TSS = 0, 10, 50 or 100 mg/L) for 12 h after which we measured a suite of biomarker responses (lysosomal membrane stability, lipid peroxidation and glutathione). In addition, we compared biomarker responses, organic energy content and metal accumulation in sponges, which had been continuously or intermittently exposed to suspended barite and natural sediment for 14 d at relevant concentrations (10 and 30 mg TSS/L). Lysosomal membrane stability was reduced in the sponges exposed to barite at 50 and 100 mg TSS/L after just 12 h and at 30 mg TSS/L for both continuous and intermittent exposures over 14 d. Evidence of compromised cellular viability was accompanied by barite analysis revealing concentrations of Cu and Pb well above reference sediments and Norwegian sediment quality guidelines. Metal bioaccumulation in sponge tissues was low and the total organic energy content (determined by the elemental composition of organic tissue) was not affected. Intermittent exposures to barite resulted in less toxicity than continuous exposure to barite. Short term exposures to bentonite did not alter any biomarker responses. This is the first time that these biomarkers have been used to indicate contaminant exposure in an arctic-boreal sponge. Our results illustrate the potential toxicity of barite and the importance of assessments that reflect the ways in which these contaminants are delivered under environmentally realistic conditions

  13. Acute toxicity, bioconcentration, elimination and antioxidant effects of fluralaner in zebrafish, Danio rerio.

    Science.gov (United States)

    Jia, Zhong-Qiang; Liu, Di; Sheng, Cheng-Wang; Casida, John E; Wang, Chen; Song, Ping-Ping; Chen, Yu-Ming; Han, Zhao-Jun; Zhao, Chun-Qing

    2018-01-01

    Fluralaner is a novel isoxazoline insecticide which shows high insecticidal activity against parasitic, sanitary and agricultural pests, but there is little information about the effect of fluralaner on non-target organisms. This study reports the acute toxicity, bioconcentration, elimination and antioxidant response of fluralaner in zebrafish. All LC50 values of fluralaner to zebrafish were higher than 10 mg L-1 at 24, 48, 72 and 96 h. To study the bioconcentration and elimination, the zebrafish were exposed to sub-lethal concentrations of fluralaner (2.00 and 0.20 mg L-1) for 15 d and then held 6 d in clean water. The results showed medium BCF of fluralaner with values of 12.06 (48 h) and 21.34 (144 h) after exposure to 2.00 and 0.20 mg L-1 fluralaner, respectively. In the elimination process, a concentration of only 0.113 mg kg-1 was found in zebrafish on the 6th day after removal to clean water. After exposure in 2.00 mg L-1 fluralaner, the enzyme activities of SOD, CAT, and GST, GSH-PX, CarE and content of MDA were measured. Only CAT and CarE activities were significantly regulated and the others stayed at a stable level compared to the control group. Meanwhile, transcriptional expression of CYP1C2, CYP1D1, CYP11A were significantly down-regulated at 12 h exposed to 2.00 mg L-1 of fluralaner. Except CYP1D1, others CYPs were up-regulated at different time during exposure periods. Fluralaner and its formulated product (BRAVECTO®) are of low toxicity to zebrafish and are rapidly concentrated in zebrafish and eliminated after exposure in clean water. Antioxidant defense and metabolic systems were involved in the fluralaner-induced toxicity. Among them, the activities of CAT and CarE, and most mRNA expression level of CYPs showed fast response to the sub-lethal concentration of fluralaner, which could be used as a biomarker relevant to the toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Integrated survey on toxic effects of lindane on neotropical fish: Corydoras paleatus and Jenynsia multidentata

    Energy Technology Data Exchange (ETDEWEB)

    Pesce, Silvia F. [Universidad Nacional de Cordoba-CONICET, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica-CIBICI, Medina Allende esq., Haya de La Torre, Ciudad Universitaria, 5000 Cordoba (Argentina); Cazenave, Jimena [Universidad Nacional de Cordoba, Facultad de Ciencias Exactas Fisicas y Naturales, Catedra Diversidad Animal II, Av. Velez Sarsfield 299, 5000 Cordoba (Argentina); Monferran, Magdalena V. [Universidad Nacional de Cordoba-CONICET, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica-CIBICI, Medina Allende esq., Haya de La Torre, Ciudad Universitaria, 5000 Cordoba (Argentina); Frede, Silvia [Universidad Nacional de Cordoba, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica-CIBICI, Hospital Nacional de Clinicas, Santa Rosa 1564, 5000 Cordoba (Argentina); Wunderlin, Daniel A. [Universidad Nacional de Cordoba-CONICET, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica-CIBICI, Medina Allende esq., Haya de La Torre, Ciudad Universitaria, 5000 Cordoba (Argentina)], E-mail: dwunder@fcq.unc.edu.ar

    2008-12-15

    We report the effect of lindane on fish experimentally exposed to lindane. Sublethal toxicity was assessed through (a) changes in histopathology; (b) the activity of GST in different organs; and (c) bioaccumulation in exposed fish. We present a survey on toxic effects of lindane at these three levels, proposing a sequence of dose-dependent effects. Physiological damage was reversible at lowest doses, but severe at the highest, including damage consistent with fibrosis in liver and karyolitic nucleus in brain of both studied species. Exposure of Jenynsia multidentata above 6 {mu}g L{sup -1} caused activation a GST in liver and gills, followed by inhibition at 75 {mu}g L{sup -1}. Interestingly, the bioaccumulation rate was suddenly increased when GST was inhibited. Corydoras paleatus exposed to 6.0 {mu}g L{sup -1} lindane did not present significant changes in GST activity; however, enzymatic inhibition was observed above 25 {mu}g L{sup -1}. The bioaccumulation rate in C. paleatus remained constant throughout the experiments. All in all, these results evidence that C. paleatus is more sensitive to lindane than J. multidentata. - We observed an inverse correlation between GST activity and bioaccumulation in exposed fish, showing a severe increase of bioaccumulation and damages upon inhibition of GST.

  15. Sub-lethal effects of the neurotoxic pyrethroid insecticide Fastac 50EC on the general motor and locomotor activities of the non-targeted beneficial carabid beetle Platynus assimilis (Coleoptera: Carabidae).

    Science.gov (United States)

    Tooming, Ene; Merivee, Enno; Must, Anne; Sibul, Ivar; Williams, Ingrid

    2014-06-01

    Sub-lethal effects of pesticides on behavioural endpoints are poorly studied in carabids (Coleoptera: Carabidae) though changes in behaviour caused by chemical stress may affect populations of these non-targeted beneficial insects. General motor activity and locomotion are inherent in many behavioural patterns, and changes in these activities that result from xenobiotic influence mirror an integrated response of the insect to pesticides. Influence of pyrethroid insecticides over a wide range of sub-lethal doses on the motor activities of carabids still remains unclear. Video tracking of Platynus assimilis showed that brief exposure to alpha-cypermethrin at sub-lethal concentrations ranged from 0.01 to 100 mg L(-1) caused initial short-term (24 h) locomotor hypo-activity. In addition, significant short- and long-term concentration and time-dependent changes occurred in general motor activity patterns and rates. Conspicuous changes in motor activity of Platynus assimilis beetles treated at alpha-cypermethrin concentrations up to 75,000-fold lower than maximum field recommended concentration (MFRC) suggest that many, basic fitness-related behaviours might be severely injured as well. These changes may negatively affect carabid populations in agro-ecosystems. Long-term hypo-activity could directly contribute to decreased trap captures of carabids frequently observed after insecticide application in the field. © 2013 Society of Chemical Industry.

  16. Effect of dichloromethylene diphosphonate on liver regeneration following thioacetamide-induced necrosis in rats

    OpenAIRE

    Bautista, Mirandeli; del Rio, María Ángeles Gómez; Benedí, Juana; Sánchez-Reus, María Isabel; Morales-González, José A.; Téllez-López, Ana María; López-Orozco, Maricela

    2013-01-01

    AIM: To study the effect of dichloromethylene diphosphonate (DMDP), a selective Kupffer cell toxicant in reference to liver damage and postnecrotic liver regeneration in rats induced by sublethal dose thioacetamide (TA).

  17. Toxic effects of the neem oil (Azadirachta indica) formulation on the stink bug predator, Podisus nigrispinus (Heteroptera: Pentatomidae).

    Science.gov (United States)

    Zanuncio, José Cola; Mourão, Sheila Abreu; Martínez, Luis Carlos; Wilcken, Carlos Frederico; Ramalho, Francisco S; Plata-Rueda, Angelica; Soares, Marcus Alvarenga; Serrão, José Eduardo

    2016-09-06

    This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults of this predator. The mortality rates of third, fourth, and fifth instar nymphs increased with increasing neem oil concentrations, suggesting low toxicity to P. nigrispinus nymphs. Mortality of adults was low, but with sublethal effects of neem products on this predator. The developmental rate of P. nigrispinus decreased with increasing neem oil concentrations. Longevity of fourth instar nymphs varied from 3.74 to 3.05 d, fifth instar from 5.94 to 4.07 d and adult from 16.5 and 15.7 d with 0.5 and 50% neem doses. Podisus nigrispinus presented malformations and increase with neem oil concentrations. The main malformations occur in wings, scutellum and legs of this predator. The neem oil at high and sub lethal doses cause mortality, inhibits growth and survival and results in anomalies on wings and legs of the non-traget predator P. nigrispinus indicating that its use associated with biological control should be carefully evaluated.

  18. Evaluating the stress response as a bioindicator of sub-lethal effects of crude oil exposure in wild house sparrows (Passer domesticus).

    Science.gov (United States)

    Lattin, Christine R; Ngai, Heather M; Romero, L Michael

    2014-01-01

    Petroleum can disrupt endocrine function in humans and wildlife, and interacts in particularly complex ways with the hypothalamus-pituitary-adrenal (HPA) axis, responsible for the release of the stress hormones corticosterone and cortisol (hereafter CORT). Ingested petroleum can act in an additive fashion with other stressors to cause increased mortality, but it is not clear exactly why--does petroleum disrupt feedback mechanisms, stress hormone production, or both? This laboratory study aimed to quantify the effects of ingested Gulf of Mexico crude oil on the physiological stress response of house sparrows (Passer domesticus). We examined baseline and stress-induced CORT, negative feedback, and adrenal sensitivity in house sparrows given a 1% oil or control diet (n = 12 in each group). We found that four weeks on a 1% oil diet did not alter baseline CORT titers or efficacy of negative feedback, but significantly reduced sparrows' ability to secrete CORT in response to a standardized stressor and adrenocorticotropin hormone injection, suggesting that oil damages the steroid-synthesizing cells of the adrenal. In another group of animals on the same 1% oil (n = 9) or control diets (n = 8), we examined concentrations of eight different blood chemistry parameters, and CORT in feathers grown before and during the feeding experiments as other potential biomarkers of oil exposure. None of the blood chemistry parameters differed between birds on the oil and control diets after two or four weeks of feeding, nor did feather CORT differ between the two groups. Overall, this study suggests that the response of CORT to stressors, but not baseline HPA function, may be a particularly sensitive bioindicator of sub-lethal chronic effects of crude oil exposure.

  19. Evaluating the stress response as a bioindicator of sub-lethal effects of crude oil exposure in wild house sparrows (Passer domesticus.

    Directory of Open Access Journals (Sweden)

    Christine R Lattin

    Full Text Available Petroleum can disrupt endocrine function in humans and wildlife, and interacts in particularly complex ways with the hypothalamus-pituitary-adrenal (HPA axis, responsible for the release of the stress hormones corticosterone and cortisol (hereafter CORT. Ingested petroleum can act in an additive fashion with other stressors to cause increased mortality, but it is not clear exactly why--does petroleum disrupt feedback mechanisms, stress hormone production, or both? This laboratory study aimed to quantify the effects of ingested Gulf of Mexico crude oil on the physiological stress response of house sparrows (Passer domesticus. We examined baseline and stress-induced CORT, negative feedback, and adrenal sensitivity in house sparrows given a 1% oil or control diet (n = 12 in each group. We found that four weeks on a 1% oil diet did not alter baseline CORT titers or efficacy of negative feedback, but significantly reduced sparrows' ability to secrete CORT in response to a standardized stressor and adrenocorticotropin hormone injection, suggesting that oil damages the steroid-synthesizing cells of the adrenal. In another group of animals on the same 1% oil (n = 9 or control diets (n = 8, we examined concentrations of eight different blood chemistry parameters, and CORT in feathers grown before and during the feeding experiments as other potential biomarkers of oil exposure. None of the blood chemistry parameters differed between birds on the oil and control diets after two or four weeks of feeding, nor did feather CORT differ between the two groups. Overall, this study suggests that the response of CORT to stressors, but not baseline HPA function, may be a particularly sensitive bioindicator of sub-lethal chronic effects of crude oil exposure.

  20. Survival rate of honeybee (Apis mellifera) workers after exposure to sublethal concentrations of imidacloprid

    NARCIS (Netherlands)

    Blacquiere, T.

    2010-01-01

    Imidacloprid is a commonly used systemic insecticide which can induce several sublethal effects. Previous research has not shown any increased mortality in bees that were fed with sublethal doses. However, there is very little research conducted with the focus on survival rate of honeybees in the

  1. Sublethal effect of neem extract on mediterranean fruit fly adults Efeito subletal de extratos de Azadirachta indica Sobre adultos de Ceratitis capitata

    Directory of Open Access Journals (Sweden)

    Márcio Alves Silva

    2013-03-01

    Full Text Available The sublethal effect of extracts of Azadirachta indica on Ceratitis capitata was evaluated. Two pairs of flies were treated in plastic tubes with cotton placed in plastic cages. An artificial diet (hydrolyzed protein + sugar was provided ad libitum. The extracts affected significantly the longevity of C. capitata. The pre-oviposition period were not significantly affected by the extracts. The A. indica branches extracted with dichloromethane (888 ppm affected significantly the fecundity and fertility, reducing the number of eggs laid to approximately 80 % and the egg hatching by 30 % at the 8th day. Therefore, the neem branches extracted with dichloromethane affected the reproduction of C. capitata.Neste estudo, avaliou-se o efeito subletal de extratos de Azadirachta indica sobre Ceratitis capitata. Os tratamentos em um tubo plástico com algodão foram expostos para dois casais numa gaiola plástica. Nessa gaiola, também foi fornecida dieta artificial (proteína hidrolisada + açúcar ad libitum. Os extratos afetaram significativamente a longevidade de C. capitata. O período de pré-oviposição não foi significativamente afetado pelos extratos. Em contrapartida, o extrato de ramos em diclorometano (888 ppm afetou a fecundidade e a fertilidade, reduzindo em 80% o número de ovos colocados e a viabilidade dos ovos em 30%, no 8º dia. Portanto, o extrato de ramos em diclorometano afeta a reprodução de C. capitata.

  2. Sub-lethal effects of dietary neonicotinoid insecticide exposure on honey bee queen fecundity and colony development

    Science.gov (United States)

    Wu-Smart, Judy; Spivak, Marla

    2016-08-01

    Many factors can negatively affect honey bee (Apis mellifera L.) health including the pervasive use of systemic neonicotinoid insecticides. Through direct consumption of contaminated nectar and pollen from treated plants, neonicotinoids can affect foraging, learning, and memory in worker bees. Less well studied are the potential effects of neonicotinoids on queen bees, which may be exposed indirectly through trophallaxis, or food-sharing. To assess effects on queen productivity, small colonies of different sizes (1500, 3000, and 7000 bees) were fed imidacloprid (0, 10, 20, 50, and 100 ppb) in syrup for three weeks. We found adverse effects of imidacloprid on queens (egg-laying and locomotor activity), worker bees (foraging and hygienic activities), and colony development (brood production and pollen stores) in all treated colonies. Some effects were less evident as colony size increased, suggesting that larger colony populations may act as a buffer to pesticide exposure. This study is the first to show adverse effects of imidacloprid on queen bee fecundity and behavior and improves our understanding of how neonicotinoids may impair short-term colony functioning. These data indicate that risk-mitigation efforts should focus on reducing neonicotinoid exposure in the early spring when colonies are smallest and queens are most vulnerable to exposure.

  3. Effects of sub-lethal levels of dichlorodiphenyltrichloroethane and dichlorodiphenyldichloroethylene on in vitro steroid biosynthesis by ovarian follicles or steroid metabolism by embryos of rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Petkam, Rakpong [Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); Renaud, Rick [Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); Lin, Lucy [Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); Boermans, Herman [Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); Leatherland, John [Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ont., N1G 2W1 (Canada)]. E-mail: jleather@ovc.uoguelph.ca

    2005-07-01

    This study examined the possibility that DDT and DDE, at sub-lethal exposure levels, exert direct effects on the biotransformation of gonadal steroids by rainbow trout (Oncorhynchus mykiss) ovarian follicles and embryos. Ovarian follicles were co-incubated with DDT or DDE at 0.01 or 1 mg l{sup -1} to examine effects of the pesticides on basal or cAMP-activated steroidogenesis. Ovarian preparations were incubated with radiolabelled [{sup 3}H]pregnenolone ([{sup 3}H]P{sub 5}), and the tritiated metabolites of [{sup 3}H]P{sub 5} metabolism were separated using high-performance liquid chromatography (HPLC). Testosterone (T) and 17{beta}-estradiol (E{sub 2}) production were also measured using radioimmunoassay (RIA). Embryos were either exposed to the pesticides in ovo, or co-incubated in vitro with the pesticides. The effect of the pesticides on embryo steroid biotransformation was examined using a range of radioactively labelled substrates, including [{sup 3}H]P{sub 5}, [{sup 3}H]progesterone ([{sup 3}H]P{sub 4}), [{sup 3}H]T and [{sup 3}H]E{sub 2}. At the concentrations used, the pesticides had no significant effect on the relative amounts of unconjugated radiolabelled steroids formed by the biotransformation of [{sup 3}H]P{sub 5} under conditions of basal or cAMP-stimulated ovarian steroidogenesis. However, DDT and DDE appeared to reduce the basal accumulation of androgen as a product of P{sub 5} biotransformation by ovarian follicles. Basal or cAMP-stimulated total estrogen production was not affected. In addition, DDT at 1 mg l{sup -1} and DDE at 0.01 mg l{sup -1} significantly increased and decreased cAMP-stimulated T accumulation, respectively. Also DDT at 0.01 mg l{sup -1} and DDE at 1 mg l{sup -1} significantly increased and decreased basal E{sub 2} accumulation, respectively. The steroid metabolites synthesized from the different substrates by embryos were essentially similar in both controls and pesticide-exposed groups, and the survival of embryos to hatch

  4. Human Health Effects Associated with Exposure to Toxic Cyanobacteria

    Science.gov (United States)

    Reports of toxic cyanobacteria blooms are increasing worldwide. Warming and eutrophic surface water systems support the development of blooms. We examine the evidence for adverse human health effects associated with exposure to toxic blooms in drinking water, recreational water a...

  5. Lethal and sublethal effects of essential oil of Lippia sidoides (Verbenaceae) and monoterpenes on Chagas’ disease vector Rhodnius prolixus

    Science.gov (United States)

    Figueiredo, Marcela B; Gomes, Geovany A; Santangelo, Jayme M; Pontes, Emerson G; Azambuja, Patricia; Garcia, Elói S; de Carvalho, Mário G

    2016-01-01

    The aim of this study was to identify the composition of the essential oil from leaves of Lippia sidoides (EOLS), a typical shrub commonly found in the dry northeast of Brazil, popularly known as “alecrim-pimenta”. Additionally, we investigated the nymphicidal, ovicidal, phagoinhibitory and excretion effects of EOLS, its major constituent thymol and its isomer carvacrol, on fourth instar nymphs and eggs of Rhodnius prolixus, the Chagas’ disease vector. The nymphicidal and ovicidal activity of thymol, carvacrol, and EOLS was assessed by tests using impregnated Petri dishes. The lethal concentration values (LC50) for EOLS, carvacrol, and thymol were 54.48, 32.98, and 9.38 mg/cm2, respectively. The ovicidal test showed that both carvacrol and thymol (50 mg/cm2) inhibited hatching (50% and 23.3%, respectively), while treatments with 10 mg/cm2 or 50 mg/cm2 EOLS did not affect the hatching rate at all (80% and 90%, respectively). We observed an anti-feeding effect in insects fed with blood containing natural products at the higher concentrations (100 µg/mL). Finally, excretion rate was affected by EOLS and carvacrol, but not by thymol. These findings offer novel insights into basic physiological processes that make the tested natural compounds interesting candidates for new types of insecticides. PMID:27878214

  6. Lethal and sublethal effects of essential oil of Lippia sidoides (Verbenaceae) and monoterpenes on Chagas' disease vector Rhodnius prolixus.

    Science.gov (United States)

    Figueiredo, Marcela B; Gomes, Geovany A; Santangelo, Jayme M; Pontes, Emerson G; Azambuja, Patricia; Garcia, Elói S; Carvalho, Mário G de

    2017-01-01

    The aim of this study was to identify the composition of the essential oil from leaves of Lippia sidoides (EOLS), a typical shrub commonly found in the dry northeast of Brazil, popularly known as "alecrim-pimenta". Additionally, we investigated the nymphicidal, ovicidal, phagoinhibitory and excretion effects of EOLS, its major constituent thymol and its isomer carvacrol, on fourth instar nymphs and eggs of Rhodnius prolixus, the Chagas' disease vector. The nymphicidal and ovicidal activity of thymol, carvacrol, and EOLS was assessed by tests using impregnated Petri dishes. The lethal concentration values (LC50) for EOLS, carvacrol, and thymol were 54.48, 32.98, and 9.38 mg/cm2, respectively. The ovicidal test showed that both carvacrol and thymol (50 mg/cm2) inhibited hatching (50% and 23.3%, respectively), while treatments with 10 mg/cm2 or 50 mg/cm2 EOLS did not affect the hatching rate at all (80% and 90%, respectively). We observed an anti-feeding effect in insects fed with blood containing natural products at the higher concentrations (100 µg/mL). Finally, excretion rate was affected by EOLS and carvacrol, but not by thymol. These findings offer novel insights into basic physiological processes that make the tested natural compounds interesting candidates for new types of insecticides.

  7. Effect of sub-lethal concentrations of permethrin on ovary activation in the predator Supputius cincticeps (Heteroptera: Pentatomidae

    Directory of Open Access Journals (Sweden)

    W. P. Lemos

    Full Text Available Insecticides may cause mortality and deleterious effects on predatory stinkbugs. For this reason, the effect of five concentrations of permethrin applied on third instar nymphs of Supputius cincticeps (Stål (Heteroptera: Pentatomidae was investigated on ovary activation in this predator. The nymphs received topical application of permethrin in the following concentrations (mg a.i./ml: 10-7, 10-6, 10-5, 10-4, and 10-3. Ovary lengths and oocyte numbers were quantified following first egg mass. Ovary length of S. cincticeps varied from 5.7 mm with 10-4 mg a.i./ml, to 6.4 mm with 10-7 mg a.i./ml, with similar values for the other permethrin concentrations and for the control. The number of oocytes per female varied from 13.5 with 10-3 mg a.i./ml, to 29.2 for the control, with significant differences.The number of oocytes per female of nymphs exposed to a permethrin concentration of 10-5 mg a.i./ml was similar to that of the control.However, the lower number of oocytes per female from nymphs exposed to other concentrations of permethrin suggests that this insecticide may affect the reproductive capacity of this predator. The results obtained are discussed in relation to tolerance of Heteroptera predators to insecticides and possible hormesis occurrence.

  8. Kinetic analysis of the swimming behavior of the goldfish, Carassius auratus, exposed to nickel: Hypoactivity induced by sublethal concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Ellgaard, E.G.; Ashley, S.E.; Langford, A.E. [Tulane Univ., New Orleans, LA (United States)] [and others

    1995-12-01

    The discharge of nickel into aquatic environments from numerous industries poses a threat to fish populations because of its toxcity. Although little is known, however, about the precise mechanism of its toxicity in freshwater fish, it produces some of the symptoms associated with heavy-metal poisoning in general; it accumulates in fish tissues and results in alterations in gill structure, including hypertrophy of respiratory and mucous cells, separation of the epithelial layer from the pillar cell system, cauterization and sloughing, and necrosis of the epithelium. The destruction of the gill lamellae decreases the ventilation rate and if severe, as after acute exposure, may cause blood hypoxia and death. The effects of short-term exposure of fish to sublethal concentrations of nickel and not as well defined. The kinetic method of Ellgaard et al., which uses locomotor activity to assess the general health of fish, is ideally suited to examine whether sublethal concentrations of nickel adversely affect fish. In previous studies, the measured changes in locomotor activity observed when fish are exposed to pollutants correlate with more specific changes, e.g., physiological, biochemical, histological or neurosensory changes, which occur under the same conditions. Thus, the kinetic method also meets the criterial for pollution early warning systems as discussed by Cairns and van der Schale. This method has previously been used to demonstrate that short-term exposure to sublethal concentrations of the heavy metals cadmium, chromium, and zinc and copper are detrimental to the health of bluegills. The present study examines the effects of short-term exposures of sublethal concentrations of nickel on the locomotor activity of the goldfish, Carassius auratus. 11 refs., 1 fig., 2 tabs.

  9. The Effect of a Sublethal Temperature Elevation on the Structure of Bacterial Communities Associated with the Coral Porites compressa

    Directory of Open Access Journals (Sweden)

    Jennifer L. Salerno

    2011-01-01

    Full Text Available Evidence points to a link between environmental stressors, coral-associated bacteria, and coral disease; however, few studies have examined the details of this relationship under tightly controlled experimental conditions. To address this gap, an array of closed-system, precision-controlled experimental aquaria were used to investigate the effects of an abrupt 1°C above summer ambient temperature increase on the bacterial community structure and photophysiology of Porites compressa corals. While the temperature treatment rapidly impacted the photophysiology of the coral host, it did not elicit a statistically significant shift in bacterial community structure from control, untreated corals as determined by terminal restriction fragment length polymorphism analysis of 16S rRNA genes. Two of three coral colonies harbored more closely related bacterial communities at the time of collection and, despite statistically significant shifts in bacterial community structure for both control and treatment corals during the 10-day acclimation period, maintained this relationship over the course of the experiment. The experimental design used in this study proved to be a robust, reproducible system for investigating coral microbiology in an aquarium setting.

  10. Environmental Mercury and Its Toxic Effects

    Directory of Open Access Journals (Sweden)

    Kevin M. Rice

    2014-03-01

    Full Text Available Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

  11. Environmental mercury and its toxic effects.

    Science.gov (United States)

    Rice, Kevin M; Walker, Ernest M; Wu, Miaozong; Gillette, Chris; Blough, Eric R

    2014-03-01

    Mercury exists naturally and as a man-made contaminant. The release of processed mercury can lead to a progressive increase in the amount of atmospheric mercury, which enters the atmospheric-soil-water distribution cycles where it can remain in circulation for years. Mercury poisoning is the result of exposure to mercury or mercury compounds resulting in various toxic effects depend on its chemical form and route of exposure. The major route of human exposure to methylmercury (MeHg) is largely through eating contaminated fish, seafood, and wildlife which have been exposed to mercury through ingestion of contaminated lower organisms. MeHg toxicity is associated with nervous system damage in adults and impaired neurological development in infants and children. Ingested mercury may undergo bioaccumulation leading to progressive increases in body burdens. This review addresses the systemic pathophysiology of individual organ systems associated with mercury poisoning. Mercury has profound cellular, cardiovascular, hematological, pulmonary, renal, immunological, neurological, endocrine, reproductive, and embryonic toxicological effects.

  12. Assessing the toxic effects of ethylene glycol ethers using Quantitative Structure Toxicity Relationship models.

    Science.gov (United States)

    Ruiz, Patricia; Mumtaz, Moiz; Gombar, Vijay

    2011-07-15

    Experimental determination of toxicity profiles consumes a great deal of time, money, and other resources. Consequently, businesses, societies, and regulators strive for reliable alternatives such as Quantitative Structure Toxicity Relationship (QSTR) models to fill gaps in toxicity profiles of compounds of concern to human health. The use of glycol ethers and their health effects have recently attracted the attention of international organizations such as the World Health Organization (WHO). The board members of Concise International Chemical Assessment Documents (CICAD) recently identified inadequate testing as well as gaps in toxicity profiles of ethylene glycol mono-n-alkyl ethers (EGEs). The CICAD board requested the ATSDR Computational Toxicology and Methods Development Laboratory to conduct QSTR assessments of certain specific toxicity endpoints for these chemicals. In order to evaluate the potential health effects of EGEs, CICAD proposed a critical QSTR analysis of the mutagenicity, carcinogenicity, and developmental effects of EGEs and other selected chemicals. We report here results of the application of QSTRs to assess rodent carcinogenicity, mutagenicity, and developmental toxicity of four EGEs: 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol and their metabolites. Neither mutagenicity nor carcinogenicity is indicated for the parent compounds, but these compounds are predicted to be developmental toxicants. The predicted toxicity effects were subjected to reverse QSTR (rQSTR) analysis to identify structural attributes that may be the main drivers of the developmental toxicity potential of these compounds. Copyright © 2010. Published by Elsevier Inc.

  13. Joint toxic effects on Caenorhabditis elegans

    NARCIS (Netherlands)

    Jonker, M.J.

    2003-01-01

    In polluted areas organisms are generally exposed to mixtures of toxic chemicals rather than a single toxicant only. Since the number of mixture toxicity studies with regard to soil systems is limited, the research in this thesis was focused on investigating ecotoxicological consequences of combined

  14. Modelling the effect of sub(lethal) heat treatment of Bacillus subtilis spores on germination rate and outgrowth to exponentially growing vegetative cells.

    Science.gov (United States)

    Smelt, J P P M; Bos, A P; Kort, R; Brul, S

    2008-11-30

    Spores of Bacillus subtilis were subjected to relatively mild heat treatments in distilled water and properties of these spores were studied. These spores had lost all or part of their dipicolinic acid (DPA) depending on the severity of the heat treatment. Even after relatively mild heat treatments these spore lost already a small but significant amount of DPA. When these spores were inoculated in nutrient medium-tryptone soy broth (TSA)-the non-lethally heated spores started to germinate. Results of classical optical density measurements showed that both phase darkening and subsequent outgrowth could be affected by sub-lethal heat. A study of single cells in TSB showed that lag times originating from exponentially growing cells followed a normal distribution, whereas lag times originating from spores followed a Weibull distribution. Besides classical optical density measurements were made to study the effect of previous heating on the kinetics of the first stages of germination. The germination kinetics could be described by the model as was proposed by Geeraerd et al. [Geeraerd, A.H., Herremans, C.H. and Van Impe, J.F., 2000. Structural model requirements to describe microbial inactivation during a mild heat treatment. International Journal of Food Microbiology 59, 185-209]. Two of the 4 parameters of the sigmoid model of Geeraerd were dependent on heating time and heating temperature, whereas the two other parameters were considered as independent of the heating conditions. Based on these observations, a secondary model could be developed that describes the combined effect of heating temperature and heating time on the kinetics of germination. To have more detailed information of the kinetics of germination samples incubated in TSB were tested at regular time intervals by flow cytometry. To that end the cells were stained with syto 9 to distinguish between the various germination stages. There was a qualitative agreement between the results of flow cytometry and

  15. Sublethal Exposure to Clove and Cinnamon Essential Oils Induces Hormetic-Like Responses and Disturbs Behavioral and Respiratory Responses in Sitophilus zeamais (Coleoptera: Curculionidae).

    Science.gov (United States)

    Haddi, Khalid; Oliveira, Eugênio E; Faroni, Lêda R A; Guedes, Daniela C; Miranda, Natalie N S

    2015-12-01

    Essential oils have been suggested as suitable alternatives for controlling insect pests. However, the potential adaptive responses elicited in insects for mitigating the actions of these compounds have not received adequate attention. Furthermore, as is widely reported with traditional insecticides, sublethal exposure to essential oils might induce stimulatory responses or contribute to the development of resistance strategies that can compromise the management of insect pests. The current study evaluated the locomotory and respiratory responses as well as the number of larvae per grain produced by the maize weevil, Sitophilus zeamais Motschulsky, after being sublethally exposed to the essential oils of clove, Syzygium aromaticum L., and cinnamon, Cinnamomum zeylanicum L. The essential oils showed similar insecticidal toxicity (exposure route: contact with dried residues; Clove LC95 = 3.96 [2.78-6.75] µl/cm(2); Cinnamon LC95 = 3.47 [2.75-4.73] µl/cm(2)). A stimulatory effect on the median survival time (TL50) was observed when insects were exposed to low concentrations of each oil. Moreover, a higher number of larvae per grain was produced under sublethal exposure to clove essential oil. S. zeamais avoided the treated areas (in free-choice experiments) and altered their mobility when sublethally exposed to both essential oils. The respiratory rates of S. zeamais (i.e., CO2 production) were significantly reduced under low concentrations of the essential oils. We recommend the consideration of the potential sublethal effects elicited by botanical pesticides during the development of integrated pest management programs aiming to control S. zeamais. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Eficiência e efeitos subletais de nim sobre Bonagota salubricola (Meyrick (Lepidoptera: Tortricidae Efficiency and sublethal effects of neem on Bonagota salubricola (Meyrick (Lepidoptera: Tortricidae

    Directory of Open Access Journals (Sweden)

    Daniel Bernardi

    2011-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência e os efeitos subletais de um inseticida à base de nim (10 g.L-1 de azadiractina A sobre a lagarta-enroladeira Bonagota salubricola em laboratório. Nos bioensaios, foi utilizado o produto à base de azadiractina NeemAzal-T/S® nas concentrações de 0,06%; 0,09%; 0,12%; 0,16%; 0,18% e 0,20% do produto comercial (p.c e uma testemunha (água destilada. A dieta artificial foi cortada em cubos e imersa nas caldas das respectivas concentrações do produto, e, em seguida, lagartas recém-eclodidas foram transferidas para tubos de vidro, contendo os cubos de dieta tratados. Quando a dieta artificial foi tratada com concentração de 0,20% do produto comercial, houve 100% da mortalidade aos 6 dias após a inoculação. Por outro lado, as concentrações de 0,16 e 0,18% prolongaram a fase larval, reduziram a viabilidade de pupas e afetaram negativamente a fecundidade do inseto.The objective of this study was to evaluate the efficiency of control and sublethal effects of neem insecticide (10 g.L-1 of azadirachtin A to the leafroller Bonagota salubricola at laboratory condition. In the bioassays, it was used an azadirachtin based product (NeemAzal-T/S® at concentrations of 0.06%, 0.09%, 0.12%, 0.16%, 0.18% and 0.20% of the commercial product (c.p. and a control (distilled water. The artificial diet was cut in cubes and immersed in the syrups of the respective product concentrations, soon afterwards recently-emerged caterpillars were transferred to glass tubes, containing the diet cubes treated. When the artificial diet was treated with a concentration of 0.20% of the commercial product, the mortality was 100% at the 6th day after inoculation. Additionally, concentrations of 0.16% and 0.18% extended the larval stages, reduced pupae viability and negatively affected the fecundity of the insect.

  17. Effects of intramuscular injection of a sublethal dose of the Egyptian cobra snake on the histological and histochemical pattern of the kidney.

    Science.gov (United States)

    Rahmy, T R

    2000-05-01

    The effects of intramuscular (i.m.) injection of a sub-lethal dose of cobra venom (0.015 microgram/gm body weight) on the histological and histochemical patterns of the kidney of rabbit were examined after 3, 6, and 12 hr. of envenomation. The histological observations after 3 hr. of envenomation showed glomerular congestion together with slight swelling of the cortical tubular epithelia. However, no changes were recorded in the medullar tubules. Serious alterations were recorded after 6 hr. of envenomation. It included thickening of the Bowman's capsules, signs of mesangiolysis, and glomerular collapse. The cortical tubular epithelia were swollen and revealed cytoplasmic granulation, coagulation, or depletion. Nuclear pyknosis and cellular damage were recorded in some areas. The medullar tubules showed cytoplasmic degeneration with no nuclear changes. By 12 hr. of envenomation a higher degree of severity was recorded. The glomerular tufts were hypertrophied or suffered from partial damage. Mesangiolysis and glomerulolysis were common and some glomerular tufts were completely transformed to clumps of hyaline casts. The cortical tubules showed hyaline coagulation, together with severe tubular damage in which the boundaries of the individual tubule cannot be identified. Numerous inflammatory cells were observed invading the damaged epithelial cells and the intertubular spaces. The medullar tubules showed swollen epithelia with cytoplasmic changes and nuclear pyknosis or karyolysis. Histochemically, the polysaccharide inclusion was increased in the glomerular tufts, the Bowman's capsules, and the basement membranes and brush borders of the renal tubules after 3 and 6 hr. of envenomation. By 12 hr. of envenomation, decreased PAS reactivity was recorded in all renal components except the glomerular tufts which exhibited intensive reactivity. Time-dependent depletion of lipid, protein, and RNA components was recorded in the renal tissues of the three envenomed groups

  18. Effect of sub-lethal damage to juvenile colonies of massive Porites spp. under contrasting regimes of temperature and water flow.

    Science.gov (United States)

    Edmunds, Peter J; Lenihan, Hunter S

    2010-01-01

    In this study, juvenile colonies of massive Porites spp. (a combination of P. lutea and P. lobata) from the lagoon of Moorea (W 149°50', S 17°30') were damaged and exposed to contrasting conditions of temperature and flow to evaluate how damage and abiotic conditions interact to affect growth, physiological performance, and recovery. The experiment was conducted in April and May 2008 and consisted of two treatments in which corals were either undamaged (controls) or damaged through gouging of tissue and skeleton in a discrete spot mimicking the effects of corallivorous fishes that utilize an excavating feeding mode. The two groups of corals were incubated for 10 days in microcosms that crossed levels of temperature (26.7 and 29.6°C) and flow (6 and 21 cm s-1), and the response assessed as overall colony growth (change in weight), dark-adapted quantum yield of PSII (Fv/Fm), and healing of the gouged areas. The influence of damage on growth was affected by temperature, but not by flow. When averaged across flow treatments, damage promoted growth by 25% at 26.7°C, but caused a 25% inhibition at 29.6°C. The damage also affected Fv/Fm in a pattern that differed between flow speeds, with a 10% reduction at 6 cm s-1, but a 4% increase at 21 cm s-1. Regardless of damage, Fv/Fm at 21 cm s-1 was 11% lower at 26.7°C than at 29.6°C, but was unaffected by temperature at 6 cm s-1. The lesions declined in area at similar rates (4-5% day-1) under all conditions, although the tissue within them regained a normal appearance most rapidly at 26.7°C and 6 cm s-1. These findings show that the response of poritid corals to sub-lethal damage is dependent partly on abiotic conditions, and they are consistent with the hypothesis that following damage, calcification and photosynthesis can compete for metabolites necessary for repair, with the outcome affected by flow-mediated mass transfer. These results may shed light upon the ways in which poritid corals respond to

  19. Effect of diet quality on chronic toxicity of aqueous lead to the amphipod Hyalella azteca

    Science.gov (United States)

    Besser, John M.; Ivey, Chris D.; Brumbaugh, William G.; Ingersoll, Christopher G.

    2016-01-01

    The authors investigated the chronic toxicity of aqueous Pb to the amphipod Hyalella azteca (Hyalella) in 42-d tests using 2 different diets: 1) the yeastþcereal leafþtrout pellet (YCT) diet, fed at the uniform low ration used in standard methods for sediment toxicity tests; and 2) a new diet of diatomsþTetraMin flakes (DT), fed at increasing rations over time, that has been optimized for use in Hyalella water-only tests. Test endpoints included survival, weight, biomass, fecundity, and total young. Lethal effects of Pb were similar for the DT and YCT tests (20% lethal concentration [LC20]¼13 mg/L and 15mg/L, respectively, as filterable Pb). In contrast, weight and fecundity endpoints were not significantly affected in the DT test at Pb concentrations up to 63 mg/L, but these endpoints were significantly reduced by Pb in the YCT test—and in a 2005 test in the same laboratory with a diet of conditioned Rabbit Chow (RC-2005). The fecundity and total young endpoints from the YCT and RC-2005 tests were considered unreliable because fecundity in controls did not meet test acceptability criteria, but both of these tests still produced lower Pb effect concentrations (for weight or biomass) than the test with the DT diet. The lowest biotic ligand model–normalized effect concentrations for the 3 tests ranged from 3.7mg/L (weight 20% effect concentration [EC20] for the RC-2005 test) to 8.2 mg/L (total young EC20 for the DT test), values that would rank Hyalella as the second or third most sensitive of 13 genera in a species sensitivity distribution for chronic Pb toxicity. These results demonstrate that toxicity tests with Hyalella fed optimal diets can meet more stringent test acceptability criteria for control performance, but suggest that results of these tests may underestimate sublethal toxic effects of Pb to Hyalella under suboptimal feeding regimes.

  20. Effect of diet quality on chronic toxicity of aqueous lead to the amphipod Hyalella azteca.

    Science.gov (United States)

    Besser, John M; Ivey, Chris D; Brumbaugh, William G; Ingersoll, Christopher G

    2016-07-01

    The authors investigated the chronic toxicity of aqueous Pb to the amphipod Hyalella azteca (Hyalella) in 42-d tests using 2 different diets: 1) the yeast + cereal leaf + trout pellet (YCT) diet, fed at the uniform low ration used in standard methods for sediment toxicity tests; and 2) a new diet of diatoms + TetraMin flakes (DT), fed at increasing rations over time, that has been optimized for use in Hyalella water-only tests. Test endpoints included survival, weight, biomass, fecundity, and total young. Lethal effects of Pb were similar for the DT and YCT tests (20% lethal concentration [LC20] = 13 μg/L and 15 μg/L, respectively, as filterable Pb). In contrast, weight and fecundity endpoints were not significantly affected in the DT test at Pb concentrations up to 63 µg/L, but these endpoints were significantly reduced by Pb in the YCT test-and in a 2005 test in the same laboratory with a diet of conditioned Rabbit Chow (RC-2005). The fecundity and total young endpoints from the YCT and RC-2005 tests were considered unreliable because fecundity in controls did not meet test acceptability criteria, but both of these tests still produced lower Pb effect concentrations (for weight or biomass) than the test with the DT diet. The lowest biotic ligand model-normalized effect concentrations for the 3 tests ranged from 3.7 μg/L (weight 20% effect concentration [EC20] for the RC-2005 test) to 8.2 μg/L (total young EC20 for the DT test), values that would rank Hyalella as the second or third most sensitive of 13 genera in a species sensitivity distribution for chronic Pb toxicity. These results demonstrate that toxicity tests with Hyalella fed optimal diets can meet more stringent test acceptability criteria for control performance, but suggest that results of these tests may underestimate sublethal toxic effects of Pb to Hyalella under suboptimal feeding regimes. Environ Toxicol Chem 2016;35:1825-1834. Published 2015 Wiley Periodicals Inc

  1. The effect of vitamin supplementation on the toxic effects of ...

    African Journals Online (AJOL)

    Dichlorvos (DDVP) is a widely used pesticide that is toxic to animals and humans but study of its effect on the microanatomy of the brain is scanty. This study was designed to investigate the ameliorating effect of vitamin supplementation on DDVP-induced neurotoxicity in the hippocampus of Wistar rats. 25 male Wistar rats ...

  2. Toxic Effects of Cannabis and Cannabinoids: Animal Data

    Directory of Open Access Journals (Sweden)

    Pierre Beaulieu

    2005-01-01

    Full Text Available The present article reviews the main toxic effects of cannabis and cannabinoids in animals. Toxic effects can be separated into acute and chronic classifications. Acute toxicity studies show that it is virtually impossible to die from acute administration of marijuana or tetrahydrocannabinol, the main psychoactive component of cannabis. Chronic toxicity involves lesions of airway and lung tissues, as well as problems of neurotoxicity, tolerance and dependence, and dysregulations in the immune and hormonal systems. Animal toxicity data, however, are difficult to extrapolate to humans.

  3. Oil and related toxicant effects on mallard immune defenses

    Energy Technology Data Exchange (ETDEWEB)

    Rocke, T.E.; Yuill, T.M.; Hinsdill, R.D.

    1984-04-01

    A crude oil, a petroleum distillate, and chemically dispersed oil were tested for their effects on resistance to bacterial infection and the immune response in waterfowl. Sublethal oral doses for mallards were determined for South Louisiana crude oil, Bunker C fuel oil a dispersant-Corexit 9527, and oil/Corexit combinations by gizzard intubation. Resistance to bacterial challange (Pasteurella multocida) was significantly lowered in mallards receiving 2.5 or 4.0 ml/kg of Bunker C fuel oil, 4.0 ml/kg of South Louisiana crude oil, and 4.0 ml/kg of a 50:1 Bunker C fuel oil/Corexit mixture daily for 28 days. Ingestion of oil or oil/Corexit mixtures had no effect on mallard antibody-producing capability as measured by the direct spleen plaque-forming assay.

  4. Polychlorinated biphenyl toxicity to Japanese quail as related to degree of chlorination

    Science.gov (United States)

    Hill, E.F.; Heath, R.G.; Spann, J.W.; Williams, J.D.

    1974-01-01

    To learn if the percentage of chlorine in a mixture of polychlorinated biphenyls (PCB's) alone determines toxicity, Japanese quail were fed diets containing Aroelor 1248, 1254, or 1260 at levels that added equal amounts of chlorine to the feed. The experiment comprised two consecutive 5-day periods; three sublethal concentrations of chlorine were evaluated during the first period and three lethal concentrations during the second period. Evaluations utilized comparisons of mortality, time to death, weight change, and food consumption. Sublethal concentrations produced no detectable effects. Lethal concentrations with equal Chlorine showed Aroelor 1248 to be less toxic at the highest chlorine concentrations, but at lower concentrations Aroelor 1254 was more toxic than Aroclor 1260. Although chlorine percentage of a PCB is positively correlated with its avian toxicity, PCB toxicity is apparently not simply a function of chlorination.

  5. Assessment of Mercury Bioaccumulation in Zebra Cichlid (Cichlasoma Nigrofasciatum Exposed to Sublethal Concentrations of Permethrin

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-12-01

    Full Text Available Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parameters including other pollutants. Therefore, the objectives of this research were to determine the effects of permethrin on bioaccumulation of mercury in zebra cichlid. Methods: Acute toxicity (LC50 of permethrin and mercury chloride was evaluated by estimating mortality in Probit Model in SPSS (version 19.0 IBM. In sub-lethal toxicity, zebra cichlid (Cichlasoma nigrofasciatum was exposed to various concentrations of permethrin (0.0, 0.40, 0.80, 1.20 and 1.60 µg.L-1 combined with 20 µg.L-1 mercury chloride for 15 days. At the end of the experiment, mercury concentrations were measured using ICP-OES-Perkin elmer (optima 7300-DV. Results: 96 h LC50 values of permethrin and mercury for C. nigrofasciatum were calculated to be 17.55 µg.L-1 and 140.38 µg.L-1, respectively. Our results clearly showed that the bioaccumulation of mercury in the specimens increased with increasing concentrations of permethrin to 1.20 and 1.60 µg.L-1. Conclusion: Increasing the concentration of permethrin had synergistic effects on the bioaccumulation of mercury in fish.

  6. Toxicity of CeO2 nanoparticles at different trophic levels--effects on diatoms, chironomids and amphibians.

    Science.gov (United States)

    Bour, Agathe; Mouchet, Florence; Verneuil, Laurent; Evariste, Lauris; Silvestre, Jérôme; Pinelli, Eric; Gauthier, Laury

    2015-02-01

    The aim of the present work is to provide wider information on the toxicity of cerium dioxide nanoparticles (CeO2 NPs) in aquatic environments, by studying the toxicity of two types of CeO2 NPs for four species (diatoms Nitzschia palea, the sediment-dwelling invertebrate Chironomus riparius, and the amphibian larvae Xenopus laevis and Pleurodeles waltl.). The two types of CeO2 NPs have different intrinsic properties: some of them are small citrate-coated spheres (2-5 nm), and the others are larger uncoated plates (20-60 nm). Acute toxicity (mortality at 48 or 96 h, depending on the test-organism) was assessed for the four species, from 0.1 to 100 mg L(-1) of NPs. Sub-lethal effects were assessed on chironomids exposed between 0.01 and 1 mg L(-1) of NPs. Mortality, growth inhibition and genotoxic effects were evaluated on amphibian larvae from 0.1 to 10 mg L(-1). Results reveal that no acute toxicity occurs on any species after short exposures, even at the highest concentrations. Mortality (35%) is observed on Xenopus larvae after 12d of exposure at the highest concentration of one type of NPs. No significant effects were observed on chironomids during chronic exposure. Xenopus larvae growth was inhibited from 1 mg L(-1) of both NPs while growth inhibition is observed on Pleurodeles only at the highest concentration of one type of NPs. No genotoxicity was observed on Xenopus but Pleurodeles exhibited dose-dependent genotoxic effects when exposed to one type of NPs. Observed differences in toxicity are discussed focusing on the studied compartment, routes of exposure, species and NPs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Effect of vitamin C in reducing the toxicity of endosulfan in liver in rabbits.

    Science.gov (United States)

    Mor, Firdevs; Ozmen, Ozlem

    2010-01-01

    In this study, the effect of endosulfan, an organochlorine pesticide, and the ameliorating effect of vitamin C on the livers of New Zealand white rabbits were studied. Livers of the rabbits were examined grossly and histopathologically, and caspase-3 activity was detected by immunohistochemical methods. A total of twenty-four rabbits were divided into four groups (n=6). Rabbits in Group I (END) were daily given a sublethal dose of endosulfan (1mg/kgbw) in corn oil by oral gavage for 6 weeks. Group II (END+C) received the same dose of endosulfan and additionally Vit C (20mg/kgbw) every other day during this period. Group III (OIL+C) received corn oil daily by oral gavage and vitamin C every other day for 6 weeks. Group IV (OIL), the control group, received only corn oil daily, by oral gavage throughout the experiment. The concentration of alpha-endosulfan in the END group was higher in livers (0.102+/-0.012ppb) than the beta-endosulfan (0.072+/-0.001ppb). Decreased accumulation of alpha and beta endosulfan was observed in the END+C group (0.025+/-0.003 and 0.016+/-0.002ppb, respectively) (pnecropsy were seen in the END group, in which swollen and pale livers were commonly observed. Hemorrhages, degenerations, necrosis, and in some rabbits bile duct hyperplasia were the marked histopathological findings of the END group. Caspase-3 positive reaction was more severe in this group than in the others. An ameliorating effect of Vit C on gross, histopathological and immunohistochemical findings was observed in the END+C group. The results revealed that endosulfan is highly toxic for rabbit livers. However, toxicity was decreased by Vit C treatment, which reduced the accumulation of endosulfan in livers four-fold. Copyright 2009 Elsevier GmbH. All rights reserved.

  8. Toxic effect of cyanobacterial blooms on the grazing activity of Daphnia magna Straus

    Directory of Open Access Journals (Sweden)

    Maria £otocka

    2001-12-01

    Full Text Available The investigations aimed to determine the impact of cyanobacteria Microcystis aeruginosa (Kütz. Kütz. and Aphanizomenon flos-aquae (L. Ralfs ex Bornet et Flah., both toxic algae, on the grazing intensity of Daphnia magna Straus. In order to determine the parameter permitting the quantitative determination of the grazing intensity of herbivorous organisms, methods based on the following techniques were applied: microscopy, to determine the degree of gut fullness; spectrophotometry, to determine the levels of chlorophyll a and its degradation products in the food composition; high-performance liquid chromatography (HPLC to determine the content of exogenous and endogenous carotenoids. Each of these methods confirmed that the tested algae species inhibited grazing intensity in D. magna Straus. The most obvious effects were obtained when M. aeruginosa (Kütz. Kütz. was used as food. With these cyanobacteria, the gut fullness indicator did not exceed 58%, and the chlorophyll a content in the digestive system of the tested D. magna was three times lower than that in the control organisms. It seems that the defensive reaction of organisms was a reversible process. However, the possibility of a long-term, sublethal influence of cyanobacteria on the physiology and internal processes of this species cannot be ruled out.

  9. The Air Toxics Health Effects Database (ATHED).

    Science.gov (United States)

    Woodall, George M; Smith, Roy L

    2008-11-15

    The Air Toxics Health Effects Database (ATHED) is currently used by the EPA's Office of Air Quality Planning and Standards (OAQPS) to support risk assessments for the Residual Risk Program. An assessment of the residual risk is required to be performed at a specified time (typically 8 years) following the promulgation of a technology-based Maximum Achievable Control Technologies (MACT) standard. The goal of the Residual Risk Program is to assure that the risk that remains after MACT standards are implemented (i.e., the "residual risk") is acceptable, and if not, to propose additional regulations to mitigate those risks. ATHED maintains all available reference values for each chemical as separate data records, and includes values for all exposure durations (acute, short-term, subchronic and chronic). These values are used as benchmarks to determine acceptable exposure levels to the hazardous air pollutants (HAPs) listed in Section 112 of the Clean Air Act. ATHED also provides useful background information on the uncertainty and/or modifying factors that were applied in the derivation of each reference value, as well as the point of departure and the critical study/studies. To facilitate comparisons across durations for a specific chemical, ATHED data can be graphically presented.

  10. Effects of salinity on olfactory toxicity and behavioral responses of juvenile salmonids from copper.

    Science.gov (United States)

    Sommers, Frank; Mudrock, Emma; Labenia, Jana; Baldwin, David

    2016-06-01

    Dissolved copper is one of the more pervasive and toxic constituents of stormwater runoff and is commonly found in stream, estuary, and coastal marine habitats of juvenile salmon. While stormwater runoff does not usually carry copper concentrations high enough to result in acute lethality, they are of concern because sublethal concentrations of copper exposure have been shown to both impair olfactory function and alter behavior in various species in freshwater. To compare these results to other environments that salmon are likely to encounter, experiments were conducted to evaluate the effects of salinity on the impairment of olfactory function and avoidance of copper. Copper concentrations well within the range of those found in urban watersheds, have been shown to diminish or eliminate the olfactory response to the amino acid, l-serine in freshwater using electro-olfactogram (EOG) techniques. The olfactory responses of both freshwater-phase and seawater-phase coho and seawater-phase Chinook salmon, were tested in freshwater or seawater, depending on phase, and freshwater-phase coho at an intermediate salinity of 10‰. Both 10‰ salinity and full strength seawater protected against the effects of 50μg copper/L. In addition to impairing olfactory response, copper has also been shown to alter salmon behavior by causing an avoidance response. To determine whether copper will cause avoidance behavior at different salinities, experiments were conducted using a multi-chambered experimental tank. The circular tank was divided into six segments by water currents so that copper could be contained within one segment yet fish could move freely between them. The presence of individual fish in each of the segments was counted before and after introduction of dissolved copper (experiments were also conducted with a submerged structural element. The presence of sub-lethal levels of dissolved copper altered the behavior of juvenile Chinook salmon by inducing an avoidance

  11. Effects of sub-lethal heroin administration on thyroid stimulating hormone (TSH), thyroid hormones (T3, T4) and thyroid gland of Mus norvegicus.

    Science.gov (United States)

    Bhoir, Kaminidevi K; Suryawanshi, S A; Pandey, A K

    2009-11-01

    Serum TSH level of control Mus norvegicus fluctuated between 498.20 +/- 21.92 and 506.80 +/- 22.35 ng ml(-1), thyroxine (T4) between 68.17 +/- 3.46 and 69.03 +/- 4.12 microg dl(-1) and triiodothyronine (T3) between 4.76 +/- 0.52 and 5.00 +/- 0.66 microg dl(-1). Sub-lethal heroin administration induced a significant decline in the levels of all the three hormones at 24 hr and 15 days post-administration. Decline in the levels of these hormones registered the lowest values (pThyroid gland of control rat consisted of spherical, round follicles lined with low cuboidal and columnar epithelial cells and lumina filled with eosinophilic colloid. Ultrastructurally, the thyroid follicular cells showed the presence of round nuclei, polymorphic mitochondria, Golgi complex as well as lysosomes located on the apical side of the nucleus and cytoplasm with different sizes of lipid droplets and smooth along with rough endoplasmic reticulum. Basal lamina of the follicular cells was often in association with the endothelium of the capillaries. Sub-lethal heroin administration for 30 days elicited degenerative changes in the follicular epithelial cells as evident by the vacuolization of cytoplasm, pycnotic nuclei and reduced colloidal content. Ultrastructurally, the thyroid follicular cells showed indented nuclei with heavy deposition of chromatin material on the inner membrane of nucleus and dilated rough endoplasmic reticulum. Along with RBC infiltration, vesiculated mitochondria owing to the loss of cristae were also seen. Diffused electron-dense material was seen at the periphery of the cell body. Heroin treatment caused cellular necrosis as revealed by the fragmentation of cytoplasmic materials in follicular epithelial cells of the gland.

  12. Assessment of metals exposure and sub-lethal effects in voles and small birds captured near the DeLong Mountain Regional Transportation System Road, Cape Krusenstern National Monument, Alaska, 2006

    Science.gov (United States)

    Brumbaugh, William G.; Mora, Miguel A.; May, Thomas W.

    2008-01-01

    Voles (n=6) and small ground-nesting birds (n=12) were live-captured near the DeLong Mountain Regional Transportation System haul road in Cape Krusenstern National Monument in northwest Alaska in 2006 to assess metals exposure and sub-lethal biological effects. Similar numbers of animals were captured from a reference site in southern Cape Krusenstern National Monument for comparison. Histopathological examination of selected organs, blood analysis, and analysis for aluminum, barium, cadmium, lead, and zinc concentrations in liver and blood samples were performed. Voles and small birds captured from near the haul road had about 20 times greater blood and liver lead concentrations and about 3 times greater cadmium concentrations when compared to those from the reference site. Barium and zinc tissue concentrations of animals collected from different sites were not remarkably different, and aluminum concentrations were below the reporting limits in most samples. There was no clear evidence of serious sub-lethal biological effects such as lesions in internal organs or DNA damage in blood in any of the animals. Accordingly, blood and liver lead concentrations in animals captured near the haul road generally were less than tissue concentration thresholds associated with serious biological effects reported from other studies; however, subtle effects resulting from lead exposure, such as the suppression of the activity of certain enzymes, cannot be ruled out for those animals nearest the haul road. Notably, liver lead concentrations of voles and small birds at the reference location were considerably less than those previously reported for similar animals at reference sites in other parts of the United States, Canada, and Europe. Results from this reconnaissance-level study indicate that voles and small birds inhabiting this area are not suffering serious biological effects as a result of metals exposure; however, continued monitoring of lead and other metals is

  13. On toxic effects of scientific journals.

    Science.gov (United States)

    Molinie, Antoinette; Bodenhausen, Geoffrey

    2013-06-01

    The advent of online publishing greatly facilitates the dissemination of scientific results. This revolution might have led to the untimely death of many traditional publishing companies, since today’s scientists are perfectly capable of writing, formatting and uploading files to appropriate websites that can be consulted by colleagues and the general public alike. They also have the intellectual resources to criticize each other and organize an anonymous peer review system. The Open Access approach appears promising in this respect, but we cannot ignore that it is fraught with editorial and economic problems. A few powerful publishing companies not only managed to survive, but also rake up considerable profits. Moreover, they succeeded in becoming influential ‘trendsetters’ since they decide which papers deserve to be published. To make money, one must set novel trends, like Christian Dior or Levi’s in fashion, and open new markets, for example in Asia. In doing so, the publishers tend to supplant both national and transnational funding agencies in defining science policy. In many cases, these agencies tend simply to adopt the commercial criteria defined by the journals, forever eager to improve their impact factors. It is not obvious that the publishers of scientific journals, the editorial boards that they appoint, or the people who sift through the vast numbers of papers submitted to a handful of ‘top’ journals are endowed with sufficient insight to set the trends of future science. It seems even less obvious that funding agencies should blindly follow the fashion trends set by the publishers. The perverse relationships between private publishers and public funding agencies may have a toxic effect on science policy.

  14. Pb Neurotoxicity: Neuropsychological Effects of Lead Toxicity

    Directory of Open Access Journals (Sweden)

    Lisa H. Mason

    2014-01-01

    Full Text Available Neurotoxicity is a term used to describe neurophysiological changes caused by exposure to toxic agents. Such exposure can result in neurocognitive symptoms and/or psychiatric disturbances. Common toxic agents include heavy metals, drugs, organophosphates, bacterial, and animal neurotoxins. Among heavy metal exposures, lead exposure is one of the most common exposures that can lead to significant neuropsychological and functional decline in humans. In this review, neurotoxic lead exposure's pathophysiology, etiology, and epidemiology are explored. In addition, commonly associated neuropsychological difficulties in intelligence, memory, executive functioning, attention, processing speed, language, visuospatial skills, motor skills, and affect/mood are explored.

  15. Validation of the target lipid model for toxicity assessment of residual petroleum constituents: monocyclic and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    McGrath, Joy A; Di Toro, Dominic M

    2009-06-01

    A method is presented for developing scientifically defensible, numeric guidelines for residual petroleum-related constituents, specifically monocyclic aromatic hydrocarbons (MAHs) and polycyclic aromatic hydrocarbons (PAHs), in the water column. The guidelines are equivalent to a HC5 (i.e., hazard concentration to 5% of the tested species, or the concentration that protects 95% of the tested species). The model of toxicity used in this evaluation is the target lipid model (TLM) that was developed for assessing the toxicity of type I narcotic chemicals. An acute to chronic ratio is used for chronic expression and sublethal effects. The TLM is evaluated by comparing predicted and observed toxicity of these petroleum components. The methodology is capable of predicting both the acute and chronic toxicity of MAHs and PAHs in single exposures and in mixtures. For acute exposures, the TLM was able to predict the toxicity to within a factor of three to five. The use of toxic units was an effective metric for expressing the toxicity of mixtures. Within the uncertainty bounds, the TLM correctly predicted where sublethal effects of edemas, hemorrhaging, and other abnormalities were observed to occur in early life-stage exposure to PAHs. The computed HC5s were lower than no-observed-effect concentrations based on growth, reproduction, and mortality endpoints and sublethal effects. The methodology presented can be used by the oil spill community to compare residual concentrations of PAHs against defensible, numeric guidelines to assess potential ecological impacts.

  16. Dose-response tests and semi-field evaluation of lethal and sub-lethal effects of slow release pyriproxyfen granules (Sumilarv®0.5G) for the control of the malaria vectors Anopheles gambiae sensu lato.

    Science.gov (United States)

    Mbare, Oscar; Lindsay, Steven W; Fillinger, Ulrike

    2013-03-14

    Recently research has shown that larviciding can be an effective tool for integrated malaria vector control. Nevertheless, the uptake of this intervention has been hampered by the need to re-apply larvicides frequently. There is a need to explore persistent, environmentally friendly larvicides for malaria vector control to reduce intervention efforts and costs by reducing the frequency of application. In this study, the efficacy of a 0.5% pyriproxyfen granule (Surmilarv®0.5G, Sumitomo Chemicals) was assessed for the control of Anopheles gambiae sensu stricto and Anopheles arabiensis, the major malaria vectors in sub-Saharan Africa. Dose-response and standardized field tests were implemented following standard procedures of the World Health Organization's Pesticide Evaluation Scheme to determine: (i) the susceptibility of vectors to this formulation; (ii) the residual activity and appropriate retreatment schedule for field application; and, (iii) sub-lethal impacts on the number and viability of eggs laid by adults after exposure to Sumilarv®0.5G during larval development. Anopheles gambiae s.s. and An. arabiensis were highly susceptible to Sumilarv®0.5G. Estimated emergence inhibition (EI) values were very low and similar for both species. The minimum dosage that completely inhibited adult emergence was between 0.01-0.03 parts per million (ppm) active ingredient (ai). Compared to the untreated control, an application of 0.018 ppm ai prevented 85% (95% confidence interval (CI) 82%-88%) of adult emergence over six weeks under standardized field conditions. A fivefold increase in dosage of 0.09 ppm ai prevented 97% (95% CI 94%-98%) emergence. Significant sub-lethal effects were observed in the standardized field tests. Female An. gambiae s.s. that were exposed to 0.018 ppm ai as larvae laid 47% less eggs, and females exposed to 0.09 ppm ai laid 74% less eggs than females that were unexposed to the treatment. Furthermore, 77% of eggs laid by females exposed to 0

  17. Toxic effect prediction of cefatirizine amidine sodium and its impurities by structure-toxicity relationship of cephalosporins.

    Science.gov (United States)

    Qian, Jianqin; Han, Ying; Li, Jin; Zhang, Jingpu; Hu, Changqin

    2018-02-01

    The three-dimensional (3D) structure-toxicity relationship of cephalosporins was explored by computing the most stable conformations of 33 kinds of cephalosporins in aqueous solution and using the teratogenicity and lethality of these compounds obtained in zebrafish embryo toxicity testing to evaluate their toxic effects. The toxic effect of cefatirizine amidine sodium, a novel cephalosporin which has finished preclinical study, was investigated. It is thought that the teratogenic effect of the triazine ring at the C-3 position is the main toxic effect of cefatirizine amidine. In addition, cefatirizine amidine is no more toxic than cefathiamidine and ceftriaxone. The results of the zebrafish embryo toxicity test combined with gene expression microarray technology were consistent with the prediction. The toxic effects of some potential process-related impurities of cefatirizine amidine were also predicted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  19. Toxic and genotoxic effects of the imazethapyr-based herbicide formulation Pivot H® on montevideo tree frog Hypsiboas pulchellus tadpoles (Anura, Hylidae).

    Science.gov (United States)

    Pérez-Iglesias, J M; Soloneski, S; Nikoloff, N; Natale, G S; Larramendy, M L

    2015-09-01

    Acute lethal and sublethal toxicity of the imidazolinone imazethapyr (IMZT)-based commercial formulation herbicide Pivot H® (10.59% IMZT) was evaluated on Hypsiboas pulchellus tadpoles. Whereas mortality was used as the end point for lethality, frequency of micronuclei (MNs) and other nuclear abnormalities as well as DNA single-strand breaks evaluated by the single cell gel electrophoresis assay were employed to test genotoxicity. Behavioral, growth, developmental, and morphological abnormalities were also employed as sublethal end points. Mortality studies revealed equivalent LC50 (96h) values of 1.49mg/L (confidence limit, 1.09-1.63) and 1.55mg/L (confidence limit, 1.51-1.60) IMZT for Gosner stage (GS) 25 and GS36, respectively. Behavioral changes, i.e., irregular swimming and immobility, as well as a decreased frequency of keratodonts were observed. The herbicide increased the frequency of MNs in circulating erythrocytes of tadpoles exposed for 48h to the highest concentration assayed (1.17mg/L). However, regardless of the concentration of the herbicide assayed, an enhanced frequency of MNs was observed in tadpoles exposed for 96h. The herbicide was able to induce other nuclear abnormalities, i.e., blebbed and notched nuclei, only when tadpoles were exposed for 96h. In addition, we observed that exposure to IMZT within the 0.39-1.17mg/L range increased the genetic damage index in treatments lasting for both 48 and 96h. This study represents the first evidence of acute lethal and sublethal effects exerted by IMZT on amphibians. Finally, our findings highlight the properties of this herbicide that jeopardize nontarget living species exposed to IMZT. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Sublethal Heavy Metal Stress Stimulates Innate Immunity in Tomato

    Directory of Open Access Journals (Sweden)

    Nilanjan Chakraborty

    2015-01-01

    Full Text Available Effect of sublethal heavy metal stress as plant biotic elicitor for triggering innate immunity in tomato plant was investigated. Copper in in vivo condition induced accumulation of defense enzymes like peroxidase (PO, polyphenol oxidase (PPO, phenylalanine ammonia-lyase (PAL, and β-1,3 glucanase along with higher accumulation of total phenol, antioxidative enzymes (catalase and ascorbate peroxidase, and total chlorophyll content. Furthermore, the treatment also induced nitric oxide (NO production which was confirmed by realtime visualization of NO burst using a fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2DA and spectrophotometric analysis. The result suggested that the sublethal dose of heavy metal can induce an array of plant defense responses that lead to the improvement of innate immunity in plants.

  1. The toxic effects of chlorophenols and associated mechanisms in fish

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Tingting; Han, Jiangyuan; Qi, Yongmei; Gu, Xueyan; Ma, Lin; Zhang, Chen; Naeem, Sajid; Huang, Dejun, E-mail: huangdj@lzu.edu.cn

    2017-03-15

    Highlights: • We review the toxic effects of chlorophenols (CPs) and underlying mechanisms in fish. • CPs induce lethal effects, oxidative stress, endocrine disruption, reproductive toxicity and apoptosis in fish. • CPs exhibit toxicity through multiple signaling pathways in fish and different pathways co-exist under the same conditions. • Studies on DNA methylation provide new insights into our understanding of epigenetic mechanisms of CPs-induced toxicity. • Mechanisms studies on CPs toxicity performed under environmental concentrations need more attentions. - Abstract: Chlorophenols (CPs) are ubiquitous contaminants in the environment primarily released from agricultural and industrial wastewater. These compounds are not readily degraded naturally, and easily accumulate in organs, tissues and cells via food chains, further leading to acute and chronic toxic effects on aquatic organisms. Herein, we review the available literature regarding CP toxicity in fish, with special emphasis on the potential toxic mechanisms. CPs cause oxidative stress via generation of reactive oxygen species, induction of lipid peroxidation and/or oxidative DNA damage along with inhibition of antioxidant systems. CPs affect immune system by altering the number of mature B cells and macrophages, while suppressing phagocytosis and down-regulating the expression of immune factors. CPs also disrupt endocrine function by affecting hormone levels, or inducing abnormal gene expression and interference with hormone receptors. CPs at relatively higher concentrations induce apoptosis via mitochondria-mediated pathway, cell death receptor-mediated pathway, and/or DNA damage-mediated pathway. CPs at relatively lower concentrations promote cell proliferation, and foster cancers-prone environment by increasing the rate of point mutations and oxidative DNA lesions. These toxic effects in fish are induced directly by CPs per se or indirectly by their metabolic products. In addition, recent

  2. Acute, Sub-lethal Cyanide Poisoning in Mice is Ameliorated by Nitrite Alone: Complications Arising from Concomitant Administration of Nitrite and Thiosulfate as an Antidotal Combination

    Science.gov (United States)

    Cambal, Leah K.; Swanson, Megan R.; Yuan, Quan; Weitz, Andrew C.; Li, Hui-Hua; Pitt, Bruce R.; Pearce, Linda L.; Peterson, Jim

    2011-01-01

    Sodium nitrite alone is shown to ameliorate sub-lethal cyanide toxicity in mice when given from ~1 hour before until 20 minutes after the toxic dose as demonstrated by the recovery of righting ability. An optimum dose (12 mg/kg) was determined to significantly relieve cyanide toxicity (5.0 mg/kg) when administered to mice intraperitoneally. Nitrite so administered was shown to rapidly produce NO in the bloodsteam as judged by the dose dependent appearance of EPR signals attributable to nitrosylhemoglobin and methemoglobin. It is argued that antagonism of cyanide inhibition of cytochrome c oxidase by NO is the crucial antidotal activity rather than the methemoglobin-forming action of nitrite. Concomitant addition of sodium thiosulfate to nitrite-treated blood resulted in the detection of sulfidomethemoblobin by EPR spectroscopy. Sulfide is a product of thiosulfate hydrolysis and, like cyanide, is known to be a potent inhibitor of cytochrome c oxidase; the effects of the two inhibitors being essentially additive under standard assay conditions, rather than dominated by either one. The findings afford a plausible explanation for an observed detrimental effect in mice associated with the use of the standard nitrite-thiosulfate combination therapy at sub-lethal levels of cyanide intoxication. PMID:21534623

  3. Protective effect of zinc against cadmium toxicity on pregnant rats ...

    African Journals Online (AJOL)

    Protective effect of zinc against cadmium toxicity on pregnant rats and their fetuses at morphological, physiological and molecular level. Ashraf El-Sayed, Salem M Salem, Amany A El-Garhy, Zeinab A Rahman, Asmaa M Kandil ...

  4. Comparative toxicity effect of bush tea leaves ( Hyptis suaveolens ...

    African Journals Online (AJOL)

    Hyptis suaveolens) were compared for their toxicity effect on the larvae of the yellow fever mosquito Aedes aegypti collected from disused tyres beside College of Natural Sciences building University of Agriculture, Abeokuta, Nigeria.

  5. Selective bioaccumulation of neonicotinoids and sub-lethal effects in the earthworm Eisenia andrei exposed to environmental concentrations in an artificial soil.

    Science.gov (United States)

    Chevillot, Fanny; Convert, Yannice; Desrosiers, Mélanie; Cadoret, Nicole; Veilleux, Éloïse; Cabana, Hubert; Bellenger, Jean-Philippe

    2017-11-01

    In this study, we evaluated the bioaccumulation of neonicotinoid insecticides in the earthworm Eisenia andrei exposed to environmental concentrations (neonicotinoids by exposing earthworms to 7 neonicotinoids alone and in more complex mixtures of 54 pesticides then 69 organic contaminants (OCs) (54 pesticides and 15 pharmaceuticals). We applied long-term (56-day) toxicity tests to further evaluate the effect of OCs on earthworms. We monitored adult survival, adult DNA damage using a comet assay on earthworm coelomocyte cells, and reproduction performance (i.e. number of cocoons and number and dry weight of juveniles). A selective bioaccumulation of neonicotinoid insecticides in adult and juvenile earthworms was found. This bioaccumulation is concomitant with a significant increase in adult DNA damage and significant effects on reproduction when earthworms were exposed to neonicotinoid insecticides alone. This study reveals a new potential point of entry of neonicotinoid insecticides into the wildlife food chain and also shows that E. andrei reproduction could be affected by long-term exposure to environmental concentrations of OCs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Acute copper toxicity in juvenile fat snook Centropomus parallelus (Teleostei: Centropomidae in sea water

    Directory of Open Access Journals (Sweden)

    Bruno L. Oliveira

    Full Text Available Three experiments were designed to assess the accumulation and acute toxicity of copper (Cu in juvenile fat snook Centropomusparallelus. The first experiment was performed to determine the 96-h lethal concentration (LC50 of Cu. The second experiment was designed to assess the effects of sublethal concentrations of Cu (0.47 and 0.94 mg/L, while the third one allowed us to test the recovery capacity of fish exposed to the sublethal concentrations Cu and kept in sea water without Cu addition. The LC50value for Cu was found to be 1.88 mg/L Cu. Fish exposed to the sublethal concentrations of Cu showed a significant accumulation of Cu in gills at 96 h respect to the control ones (0.43 µg/g Cu. No significant difference was observed in the accumulation of Cu in gills between fish exposed to 0.47 mg/L (1.09 µg/g Cu and 0.94 mg/L (1.26 µg/g Cu. Exposure (24 and 96 h to the sublethal concentrations of Cu tested induced DNA damage in the erythrocytes. The results show that acute exposure to sublethal concentrations induces Cu accumulation and DNA damage in fish, these effects being recovered after 240 h in sea water without Cu addition.

  7. Sublethal red tide toxin exposure in free-ranging manatees (Trichechus manatus) affects the immune system through reduced lymphocyte proliferation responses, inflammation, and oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Catherine J., E-mail: cjwalsh@mote.org [Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236 (United States); Butawan, Matthew, E-mail: mattbutawan@outlook.com [Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236 (United States); Yordy, Jennifer, E-mail: jennifer.e.balmer@gmail.com [Marine Immunology Program, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236 (United States); Ball, Ray, E-mail: Ray.Ball@lowryparkzoo.com [Lowry Park Zoo, 1101 W Sligh Ave, Tampa, FL 33604 (United States); Flewelling, Leanne, E-mail: Leanne.Flewelling@MyFWC.com [Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, 100 8th Ave SE, St. Petersburg, FL 33701 (United States); Wit, Martine de, E-mail: Martine.deWit@MyFWC.com [Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, 100 8th Ave SE, St. Petersburg, FL 33701 (United States); Bonde, Robert K., E-mail: rbonde@usgs.gov [U.S. Geological Survey, Sirenia Project, 7920 NE 71st Street, Gainesville, FL 32653 (United States)

    2015-04-15

    Highlights: • Sublethal brevetoxin exposure affects manatee immune function. • Plasma brevetoxin levels correlate with oxidative stress in rescued manatees. • Brevetoxin exposure affects lymphocyte proliferation in rescued manatees. • Plasma brevetoxin concentrations ranged from 0 to 19 ng PbTx-3 eq/mL. - Abstract: The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected by exposure to blooms of the toxic dinoflagellate, Karenia brevis. K. brevis blooms are common in manatee habitats of Florida’s southwestern coast and produce a group of cyclic polyether toxins collectively referred to as red tide toxins, or brevetoxins. Although a large number of manatees exposed to significant levels of red tide toxins die, several manatees are rescued from sublethal exposure and are successfully treated and returned to the wild. Sublethal brevetoxin exposure may potentially impact the manatee immune system. Lymphocyte proliferative responses and a suite of immune function parameters in the plasma were used to evaluate effects of brevetoxin exposure on health of manatees rescued from natural exposure to red tide toxins in their habitat. Blood samples were collected from rescued manatees at Lowry Park Zoo in Tampa, FL and from healthy, unexposed manatees in Crystal River, FL. Peripheral blood leukocytes (PBL) isolated from whole blood were stimulated with T-cell mitogens, ConA and PHA. A suite of plasma parameters, including plasma protein electrophoresis profiles, lysozyme activity, superoxide dismutase (SOD) activity, and reactive oxygen/nitrogen (ROS/RNS) species, was also used to assess manatee health. Significant decreases (p < 0.05) in lymphocyte proliferation were observed in ConA and PHA stimulated lymphocytes from rescued animals compared to non-exposed animals. Significant correlations were observed between oxidative stress markers (SOD, ROS/RNS) and plasma brevetoxin concentrations. Sublethal exposure to brevetoxins in the

  8. Acute and sub-lethal exposure to copper oxide nanoparticles causes oxidative stress and teratogenicity in zebrafish embryos.

    Science.gov (United States)

    Ganesan, Santhanamari; Anaimalai Thirumurthi, Naveenkumar; Raghunath, Azhwar; Vijayakumar, Savitha; Perumal, Ekambaram

    2016-04-01

    Nano-copper oxides are a versatile inorganic material. As a result of their versatility, the immense applications and usage end up in the environment causing a concern for the lifespan of various beings. The ambiguities surround globally on the toxic effects of copper oxide nanoparticles (CuO-NPs). Hence, the present study endeavored to study the sub-lethal acute exposure effects on the developing zebrafish embryos. The 48 hpf LC50 value was about 64 ppm. Therefore, we have chosen the sub-lethal dose of 40 and 60 ppm for the study. Accumulation of CuO-NPs was evidenced from the SEM-EDS and AAS analyzes. The alterations in the AChE and Na(+)/K(+)-ATPase activities disrupted the development process. An increment in the levels of oxidants with a concomitant decrease in the antioxidant enzymes confirmed the induction of oxidative stress. Oxidative stress triggered apoptosis in the exposed embryos. Developmental anomalies were observed with CuO-NPs exposure in addition to oxidative stress in the developing embryos. Decreased heart rate and hatching delay hindered the normal developmental processes. Our work has offered valuable data on the connection between oxidative stress and teratogenicity leading to lethality caused by CuO-NPs. A further molecular mechanism unraveling the uncharted connection between oxidative stress and teratogenicity will aid in the safe use of CuO-NPs. Copyright © 2015 John Wiley & Sons, Ltd.

  9. Effect of the selective pressure of sub-lethal level of heavy metals on the fate and distribution of ARGs in the catchment scale.

    Science.gov (United States)

    Xu, Yan; Xu, Jian; Mao, Daqing; Luo, Yi

    2017-01-01

    Our previous study demonstrated that high levels of antibiotic resistance genes (ARGs) in the Haihe River were directly attributed to the excessive use of antibiotics in animal agriculture. The antibiotic residues of the Xiangjiang River determined in this study were much lower than those of the Haihe River, but the relative abundance of 16 detected ARGs (sul1, sul2 and sul3, qepA, qnrA, qnrB, qnrD and qnrS, tetA, tetB, tetW, tetM, tetQ and tetO, ermB and ermC), were as high as the Haihe River particularly in the downstream of the Xiangjiang River which is close to the extensive metal mining. The ARGs discharged from the pharmaceutical wastewater treatment plant (PWWTP) are a major source of ARGs in the upstream of the Xiangjiang River. In the downstream, selective stress of heavy metals rather than source release had a significant influence on the distinct distribution pattern of ARGs. Some heavy metals showed a positive correlation with certain ARG subtypes. Additionally, there is a positive correlation between individual ARG subtypes and heavy metal resistance genes, suggesting that heavy metals may co select the ARGs on the same plasmid of antibiotic resistant bacteria. The co-selection mechanism between specific metal and antibiotic resistance was further confirmed by these isolations encoding the resistance genotypes to antibiotics and metals. To our knowledge, this is the first study on the fate and distribution of ARGs under the selective pressure exerted by heavy metals in the catchment scale. These results are beneficial to understand the fate, and to discern the contributors of ARGs from either the source release or the selective pressure by sub-lethal levels of environmental stressors during their transport on a river catchment scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Efectos subletales de la lambda-cialotrina sobre Eisenia fetida (Annelida, Oligochaeta, Lumbricidae Sublethal effects of lambda-cyhalothrin on Eisenia fetida (Annelida, Oligochaeta, Lumbricidae

    Directory of Open Access Journals (Sweden)

    Tamara Ricardo

    2010-07-01

    Full Text Available El uso intensivo de agroquímicos provoca efectos dañinos sobre la fauna no blanco. Dentro de la misma, los oligoquetos contribuyen a mantener la estructura y fertilidad del suelo. La lambda-cialotrina es uno de los insecticidas piretroides más utilizados en la Argentina, pero son escasos los datos existentes acerca de su toxicidad sobre oligoquetos. Los objetivos de este trabajo fueron evaluar mediante bioensayos de toxicidad crónica los efectos de lambda-cialotrina (producto comercial al 5% en Eisenia fetida sobre los parámetros de comportamiento, sobrevivencia, biomasa, reproducción y bioacumulación, así como la persistencia en suelo OECD de dicho tóxico. Los resultados muestran un comportamiento de huída intenso a partir de la concentración más baja, con un EC50 de 1,36 mg kg-1 (95% C.L. 0,24 - 2,80. No se observaron efectos en sobrevivencia y alimentación. La reproducción fue afectada significativamente (F= 11,94, PThe intensive use of agrochemicals has deleterious effects on non-target organisms. Among these organisms, earthworms are important because of their role in keeping the soil structure and fertility. Lambda-cyhalothrin is one of the most widely used pyrethroid insecticide in Argentina, but there are not enough studies of the effects of this pesticide on earthworms. The goals of this work were to perform chronic toxicity bioassays to determine the effects of commercial lambda-cyhalothrin (at 5% on Eisenia fetida. The parameters of behaviour, survival, biomass, reproduction, bioaccumulation and the degradation time of lambda-cyhalotrin in an OECD standard soil were also estimated. Results showed a hard avoidance behaviour in the lowest lambda-cyhalothrin concentration with an EC50 of 1.36 mg kg-1 (95% C.L 0.24-2.80. Eisenia fetida chronic test survival and feeding were not affected by lambda-cyhalothrin but negative effects on reproduction were significant (P<0.05. Cocoon production and fertility were reduced and

  11. Toxicity of algal-derived aldehydes to two invertebrate species: Do heavy metal pollutants have a synergistic effect?

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Rebecca L. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom)]. E-mail: r.l.taylor@ncl.ac.uk; Caldwell, Gary S. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom); Bentley, Matthew G. [School of Marine Science and Technology, University of Newcastle upon Tyne, Ridley Building, Claremont Road, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2005-08-15

    The recent discovery of the production of anti-proliferative aldehydes in a variety of microalgal species has lead to considerable investigation into the effects of these toxins on aquatic invertebrates. Studies have, however, rarely considered the impact pollutants may have on grazer responses to algal toxins. In this study, the acute toxicities of five aldehydes to the rotifer Brachionus plicatilis and nauplii of the brine shrimp Artemia salina are examined using immersion assays. In addition, the effect of a representative of these aldehydes in the presence of sub-lethal levels of heavy metals was examined. B. plicatilis generally showed greater sensitivity to the aldehydes than A. salina. The polyunsaturated 2-trans,4-trans-decadienal was the most toxic to both species having 24 h LD{sub 50} values of 7 and 20 {mu}M for B. plicatilis and A. salina, respectively. The remaining aldehydes had different orders of toxicity for the two species with a stronger relationship observed between mortality and aldehyde carbon-chain length for A. salina whereas B. plicatilis mortality showed a stronger dependence on the presence of carbon-carbon double bonds in the aldehydes. The presence of 1 {mu}M of copper sulphate in solutions of decadienal resulted in the reduction of the 24 h LD{sub 50} of decadienal by approximately a third for both species. 1 {mu}M of copper chloride in solutions of decadienal reduced the 24 h LD{sub 50} of decadienal to A. salina nauplii by approximately 11% and 1 {mu}M zinc sulphate caused a reduction of only 3%. Pre-exposure of the organisms to 1 {mu}M copper sulphate had no significant impact on their subsequent mortality in decadienal. The ecological implications and the possible mechanisms for the action of copper sulphate on the response of organisms to decadienal are discussed.

  12. Effect of dietary Spirulina on reduction of copper toxicity and improvement of growth, blood parameters and phosphatases activities in carp, Cirrhinus mrigala (Hamilton, 1822).

    Science.gov (United States)

    James, R; Sampath, K; Nagarajan, R; Vellaisamy, P; Manikandan, M Maripandi

    2009-09-01

    The effect of Spirulina supplementation on reduction of copper toxicity based on food utilization, phosphatases activities and selected haematological parameters was studied in a freshwater cultivable fish C. mrigala. Metal concentration in medium, body tissues and fecal matter was also analysed. Sublethal exposure of C. mrigala fed Spirulina-free diet significantly reduced the consumption and growth rates, phosphatases activities and haematological parameters. However, the above parameters enhanced in the copper exposed fish fed with Spirulina supplemented diets. A significant positive correlation was obtained for the relationship between supplementation of dietary Spirulina and copper defecation through feces. Among the doses of Spirulina supplementation, 6% addition has been considered optimum for C. mrigala since this dose produces maximum elimination of copper from the body and feces and better improvement on growth, phosphatases activities and haematological parameters.

  13. Toxic effects on survival and reproduction, a process oriented approach

    Energy Technology Data Exchange (ETDEWEB)

    Bedaux, J.J.M.; Kooijman, S.A.L.M. [Vrije Univ., Amsterdam (Netherlands). Dept. of Theoretical Biology

    1995-12-31

    The authors present a new analysis of survival and reproduction data from toxicity tests. The analysis is based on the Dynamic Energy Budget theory for feeding, growth and reproduction, and a one-compartment kinetics for the toxic compound. The toxic effect size depends on the internal concentration. Effects on survival occur via the hazard rate, which is set equal to the killing rate times the internal concentration that exceeds a threshold value. Effects on reproduction depend on the mode of action of the toxicant: direct effects (mortality during oogenesis or energy costs per egg), or indirect effects (via growth, maintenance or assimilation). The effects on energetic parameters are quantified by the ratio between the internal concentration that exceeds a threshold value, and the tolerance concentration. The process-based models quantify effects as functions of exposure time and (external) concentration on a mechanistic basis. The parameters (no effect concentration, killing rate, tolerance concentration and elimination rate) are independent from the chosen exposure time of the toxicity test. The standard log-logistic models are purely descriptive, have more parameters and are sensitive to the chosen exposure time. The estimation of no-effect concentrations (NOEC`s as well as parametric NEC`S) in standard statistical analyses is problematic. Application to ring test data for chronic tests on Daphnia magna and other toxicity data reveals that these problems do not occur with the analysis, due to the absence of free gradient parameters. It is possible to obtain estimates for the standard model parameters from the new parameters, but not vice versa. The authors believe that the analysis provides a better basis for risk assessment and QSAR studies than the standard one.

  14. Development and application of long-term sublethal whole sediment tests with Arenicola marina and Corophium volutator using Ivermectin as the test compound.

    Science.gov (United States)

    Allen, Yvonne T; Thain, John E; Haworth, Sarah; Barry, Jon

    2007-03-01

    Short-term whole sediment tests using the amphipod Corophium volutator and the polychaete Arenicola marina are now routinely used in Europe to assess the acute toxicity of marine sediments. However, there is still a need to develop longer-term assays which measure effects on sublethal endpoints that are more relevant to predicting impacts at the population level. The effect of increasing exposure times and measuring additional endpoints such as growth, on the sensitivity of these assays was investigated. The test compound used was the chemotherapeutant Ivermectin (IVM), used in aquaculture to treat sea lice infestations. IVM was found to be acutely toxic to both test organisms. Extending the lugworm test to 100 days increased sensitivity of survival by a factor of three; a significant reduction in casting rate was observed at concentrations an order of magnitude lower. This assay shows potential for detecting the sublethal effects of low concentrations of sediment contaminants. Increasing the exposure time did not seem to affect the sensitivity of the amphipod, but further method development is required.

  15. A fluorescence-based hydrolytic enzyme activity assay for quantifying toxic effects of Roundup® to Daphnia magna

    DEFF Research Database (Denmark)

    Ørsted, Michael; Roslev, Peter

    2015-01-01

    Daphnia magna is a widely used model organism for aquatic toxicity testing. In the present study, we investigated the hydrolytic enzyme activity of D. magna after exposure to toxicant stress. In vivo enzyme activity was quantified using 15 fluorogenic enzyme probes based on 4-methylumbelliferyl...... showed that hydrolytic enzyme activity was quantifiable as a combination of whole body fluorescence of D. magna, and fluorescence of the surrounding water. Exposure of D. magna to lethal and sublethal concentrations of Roundup® resulted in loss of whole body enzyme activity, and release of cell...

  16. Locomotion Inhibition of Cimex lectularius L. Following Topical, Sublethal Dose Application of the Chitin Synthesis Inhibitor Lufenuron

    Directory of Open Access Journals (Sweden)

    Brittany Campbell

    2017-09-01

    Full Text Available To date, few studies have evaluated chitin synthesis inhibitors against bed bugs, although they would provide an alternative mode of action to circumvent insecticide resistance. Acute and sublethal effects of lufenuron were evaluated against two strains of the common bed bug. Combined acute and sublethal effects were used to calculate effective doses. The dose that was effective against 50% of Harlan strain bed bugs was 0.0081% (w/v, and was much higher against Bradenton strain bed bugs (1.11% w/v. Sublethal doses were chosen to determine the effect that leg abnormalities had on pulling force. Both Harlan and Bradenton strain bed bugs had significantly lower locomotion ability (p < 0.0001 following topical application of lufenuron. The observed sublethal effects that limit locomotion could prevent bed bugs from moving within a domicile and taking a blood meal, subsequently reducing a bed bug population over time.

  17. Inhibition of acetylcholinesterase in guppies (Poecilia reticulata) by chlorpyrifos at sublethal concentrations: Methodological aspects

    Energy Technology Data Exchange (ETDEWEB)

    van der Wel, H.; Welling, W.

    1989-04-01

    Acetylcholinesterase activity is a potential biochemical indicator of toxic stress in fish and a sensitive parameter for testing water for the presence of organophosphates. A number of methodological aspects regarding the determination of the in vivo effect of chlorpyrifos on acetylcholinesterase in guppies have been investigated. It was found that with acetylthiocholine as a substrate, the contribution of pseudocholinesterase to the total cholinesterase activity can be neglected. Protection of acetylcholinesterase of guppies exposed to chlorpyrifos from additional, artifactual in vitro enzyme inhibition during homogenization is necessary. Very low concentrations of acetone in the exposure medium, resulting from dilution of the stock solution of chlorpyrifos in acetone, can result in large decreases in the oxygen content of this medium. This may affect the uptake rate of the toxic compound and, thereby, cholinesterase inhibition. Very low, sublethal concentrations of chlorpyrifos result in high inhibition levels of acetylcholinesterase (80-90%) in guppies within 2 weeks of continuous exposure. Recovery of the enzyme activity occurs after the exposed animals are kept in clean medium for 4 days, but the rate of recovery is considerably lower than the rate of inhibition.

  18. Impacts of Sublethal Mercury Exposure on Birds: A Detailed Review.

    Science.gov (United States)

    Whitney, Margaret C; Cristol, Daniel A

    Mercury is a ubiquitous environmental contaminant known to accumulate in, and negatively affect, fish-eating and oceanic bird species, and recently demonstrated to impact some terrestrial songbirds to a comparable extent. It can bioaccumulate to concentrations of >1 μg/g in tissues of prey organisms such as fish and insects. At high enough concentrations, exposure to mercury is lethal to birds. However, environmental exposures are usually far below the lethal concentrations established by dosing studies.The objective of this review is to better understand the effects of sublethal exposure to mercury in birds. We restricted our survey of the literature to studies with at least some exposures >5 μg/g. The majority of sublethal effects were subtle and some studies of similar endpoints reached different conclusions. Strong support exists in the literature for the conclusion that mercury exposure reduces reproductive output, compromises immune function, and causes avoidance of high-energy behaviors. For some endpoints, notably certain measures of reproductive success, endocrine and neurological function, and body condition, there is weak or contradictory evidence of adverse effects and further study is required. There was no evidence that environmentally relevant mercury exposure affects longevity, but several of the sublethal effects identified likely do result in fitness reductions that could adversely impact populations. Overall, 72% of field studies and 91% of laboratory studies found evidence of deleterious effects of mercury on some endpoint, and thus we can conclude that mercury is harmful to birds, and the many effects on reproduction indicate that bird population declines may already be resulting from environmental mercury pollution.

  19. Effect of cypermethrin toxicity on enzyme activities in the freshwater ...

    African Journals Online (AJOL)

    Cyprinus carpio a freshwater fish, was exposed to lethal concentration (7.5 μg/L) for one, three, five, seven and nine days and, sublethal concentration (1.5 μg/L) for 1, 7, 14, 21 and 28 days of cypermethrin, respectively to observe the enzyme activity in functionally three different tissues; that is, muscle, gill and liver.

  20. Dose–response tests and semi-field evaluation of lethal and sub-lethal effects of slow release pyriproxyfen granules (Sumilarv®0.5G) for the control of the malaria vectors Anopheles gambiae sensu lato

    Science.gov (United States)

    2013-01-01

    Background Recently research has shown that larviciding can be an effective tool for integrated malaria vector control. Nevertheless, the uptake of this intervention has been hampered by the need to re-apply larvicides frequently. There is a need to explore persistent, environmentally friendly larvicides for malaria vector control to reduce intervention efforts and costs by reducing the frequency of application. In this study, the efficacy of a 0.5% pyriproxyfen granule (Surmilarv®0.5G, Sumitomo Chemicals) was assessed for the control of Anopheles gambiae sensu stricto and Anopheles arabiensis, the major malaria vectors in sub-Saharan Africa. Methods Dose–response and standardized field tests were implemented following standard procedures of the World Health Organization’s Pesticide Evaluation Scheme to determine: (i) the susceptibility of vectors to this formulation; (ii) the residual activity and appropriate retreatment schedule for field application; and, (iii) sub-lethal impacts on the number and viability of eggs laid by adults after exposure to Sumilarv®0.5G during larval development. Results Anopheles gambiae s.s. and An. arabiensis were highly susceptible to Sumilarv®0.5G. Estimated emergence inhibition (EI) values were very low and similar for both species. The minimum dosage that completely inhibited adult emergence was between 0.01-0.03 parts per million (ppm) active ingredient (ai). Compared to the untreated control, an application of 0.018 ppm ai prevented 85% (95% confidence interval (CI) 82%-88%) of adult emergence over six weeks under standardized field conditions. A fivefold increase in dosage of 0.09 ppm ai prevented 97% (95% CI 94%-98%) emergence. Significant sub-lethal effects were observed in the standardized field tests. Female An. gambiae s.s. that were exposed to 0.018 ppm ai as larvae laid 47% less eggs, and females exposed to 0.09 ppm ai laid 74% less eggs than females that were unexposed to the treatment. Furthermore, 77

  1. Toxicity effects of ethanol extract of Simarouba versicolor on ...

    African Journals Online (AJOL)

    Toxicity effects of ethanol extract of Simarouba versicolor on reproductive parameters in female Wistar rats. ... The effects of ethanolic extract of the bark of S. versicolor (Sv-EtOH) on the reproductive system of rats were investigated; also the influence of estrogenic and/or antiestrogenic activity, estrous cycle, pregnancy, ...

  2. Toxic effects of the administration of Mikania glomerata Sprengel ...

    African Journals Online (AJOL)

    Herbal medicine is an ancient practice that has been gaining acceptance of the medical class through scientific studies that prove its effectiveness. However, its use should still be cautious. Medicinal plants have potential toxic effects not yet discovered, and may have unproven interactions with other medications. The use of ...

  3. Chronic toxicity of verapamil on juvenile rainbow trout (Oncorhynchus mykiss): effects on morphological indices, hematological parameters and antioxidant responses.

    Science.gov (United States)

    Li, Zhi-Hua; Velisek, Josef; Zlabek, Vladimir; Grabic, Roman; Machova, Jana; Kolarova, Jitka; Li, Ping; Randak, Tomas

    2011-01-30

    In this study, the toxic effects of verapamil (VRP) were studied on juvenile rainbow trout, Oncorhynchus mykiss, by chronic semi-static bioassay. Fish were exposed to sublethal concentrations of VRP (0.5, 27 and 270 μg/L) for 0, 21 and 42 d. Multiple biomarkers were measured, including morphological indices, hematological parameters and antioxidant responses of different tissues (brain, gill, liver, muscle and intestine). Based on the results, there was no significant change in all parameters measured in fish exposed to VRP at environmental related concentration, but VRP-induced stress in fish exposed to higher concentrations reflected the significant changes of physiological and biochemical responses. Through principal component analysis and integrated biomarker response assessment, effects induced by VRP-stress in each test group were distinguished. Additionally, all parameters measured in this study displayed various dependent patterns to VRP concentrations and exposure time using two-way ANOVA statistic analysis. In short, the multiple responses in fish indicated that VRP induced physiological stress and could be used as potential biomarkers for monitoring residual VRP in aquatic environment; but molecular and genetic mechanisms of these physiological responses in fish are not clear and need to be further studied. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Toxic effects of Cadmium on the garden snail (Helix aspersa)

    Energy Technology Data Exchange (ETDEWEB)

    Russell, L.K. (Northrop Services Inc., Corvallis, OR); DeHaven, J.I.; Botts, R.P.

    1981-05-01

    Spreading treated municipal wastes on agricultural and forest lands is becoming an established method of disposal. However, there is concern about the deleterious effects of toxicants, particularly cadmium, in the sludges. Cadmium concentrations in sewage sludge have been reported as high as 1500 ppM. The work reported here is a part of a larger project to investigate the ecological effects of municipal wastes on forest lands. Snails, Helix aspersa, were chosen to examine the entrance of cadmium into terrestrial food chains. This experiment was designed to determine cadmium accumulation, acute toxicity, and behavioral, reproductive and growth responses with increasing levels of cadmium.

  5. Sublethal exposure to crude oil during embryonic development alters cardiac morphology and reduces aerobic capacity in adult fish.

    Science.gov (United States)

    Hicken, Corinne E; Linbo, Tiffany L; Baldwin, David H; Willis, Maryjean L; Myers, Mark S; Holland, Larry; Larsen, Marie; Stekoll, Michael S; Rice, Stanley D; Collier, Tracy K; Scholz, Nathaniel L; Incardona, John P

    2011-04-26

    Exposure to high concentrations of crude oil produces a lethal syndrome of heart failure in fish embryos. Mortality is caused by cardiotoxic polycyclic aromatic hydrocarbons (PAHs), ubiquitous components of petroleum. Here, we show that transient embryonic exposure to very low concentrations of oil causes toxicity that is sublethal, delayed, and not counteracted by the protective effects of cytochrome P450 induction. Nearly a year after embryonic oil exposure, adult zebrafish showed subtle changes in heart shape and a significant reduction in swimming performance, indicative of reduced cardiac output. These delayed physiological impacts on cardiovascular performance at later life stages provide a potential mechanism linking reduced individual survival to population-level ecosystem responses of fish species to chronic, low-level oil pollution.

  6. Effect of temperature on heavy metal toxicity to earthworm Lumbricus terrestris (Annelida: Oligochaeta).

    Science.gov (United States)

    Khan, M A Q; Ahmed, S A; Salazar, A; Gurumendi, J; Khan, A; Vargas, M; von Catalin, B

    2007-10-01

    Earthworms (Lumbricus terrestris) acclimated at 2 degrees C above their habitat temperature (10-12 degrees C) showed about 5% increase in basal rate of oxygen consumption, which increased to about 38% in 14-16 degrees C- and 40% in 16-18 degrees C-, but decreased by 84% in 20-22 degrees C-acclimated worms. Temperature also increased the blood hemoglobin (Hb) concentration, which decreased slightly in 20-22 degrees C-acclimated worms. The worms acclimated at 20-22 degrees C showed their blood to be hypovolemic than that of 10-12 degrees C worms indicating dehydration. Pre-exposure of 10-14 degrees C-acclimated worms to sublethal concentrations of zinc, copper, and lead did not significantly affect the rate of respiration. However, at higher temperatures all these metals inhibited oxygen consumption; zinc, lead, and cadmium by approximately 11% and copper by approximately 18% of that at 14-16 degrees C. At 20-22 degrees C, the respiration was further inhibited, 36% by copper, 18% by cadmium, and approximately 10% by lead and zinc. Copper, lead, and zinc decreased the temperature-enhanced increase in blood Hb concentration at all temperatures. In 20-22 degrees C-acclimated worms heavy metal exposure slightly lowered the oxygen affinity of Hb as well as caused shifts in carbon monoxide difference spectra. The acute toxicity of these metals was not affected by a 2 degrees C rise in acclimation temperature but increased by 17% (lead), 33% (copper), and 5% (zinc) in 14-16 degrees C- and by 40% (lead), 149% (copper), and 132% (zinc) in 20-22 degrees C-acclimated worms. The increase in toxicity of metals caused by high temperatures may be due to limiting the scope of aerobic metabolism (oxygen extraction, transport, and utilization) via quantitative and qualitative effects on Hb. This terrestrial species appears to be tolerant of slight increases in habitat temperature, such as that expected with current global climate change. 2007 Wiley Periodicals, Inc.

  7. Real-time monitoring of cell viability and cell density on the basis of a three dimensional optical reflectance method (3D-ORM): investigation of the effect of sub-lethal and lethal injuries.

    Science.gov (United States)

    Brognaux, Alison; Bugge, Jörg; Schwartz, Friedel H; Thonart, Philippe; Telek, Samuel; Delvigne, Frank

    2013-07-01

    Cell density and cell viability have been followed on-line by using a three-dimensional optical reflectance method (3D-ORM) probe. This method has allowed to highlight the differences between a well-mixed and a scale-down bioreactor configured in order to reproduce mixing deficiencies during a fed-batch culture of Escherichia coli. These differences have been observed both for the obscuration factor (OBF) and the coincidence probability delivered by the probe. These parameters are correlated to flow cytometry measurement based on the PI-uptake test and cell density based on optical density measurement. This first set of results has pointed out the fact that the 3D-ORM probe is sensitive to sub-lethal injuries encountered by microbial cells in process-related conditions. The effect of lethal injuries has been further investigated on the basis of additional experiments involving heat stress and a sharp increase of the OBF has been observed indicating that cells are effectively injured by the increase of temperature. However, further improvement of the probe are needed in order to give access to single-cell measurements.

  8. The effects of weathering and chemical dispersion on Deepwater Horizon crude oil toxicity to mahi-mahi (Coryphaena hippurus) early life stages.

    Science.gov (United States)

    Esbaugh, Andrew J; Mager, Edward M; Stieglitz, John D; Hoenig, Ronald; Brown, Tanya L; French, Barbara L; Linbo, Tiffany L; Lay, Claire; Forth, Heather; Scholz, Nathaniel L; Incardona, John P; Morris, Jeffrey M; Benetti, Daniel D; Grosell, Martin

    2016-02-01

    To better understand the impact of the Deepwater Horizon (DWH) incident on commercially and ecologically important pelagic fish species, a mahi-mahi spawning program was developed to assess the effect of embryonic exposure to DWH crude oil with particular emphasis on the effects of weathering and dispersant on the magnitude of toxicity. Acute lethality (96 h LC50) ranged from 45.8 (28.4-63.1) μg l(-1) ΣPAH for wellhead (source) oil to 8.8 (7.4-10.3) μg l(-1) ΣPAH for samples collected from the surface slick, reinforcing previous work that weathered oil is more toxic on a ΣPAH basis. Differences in toxicity appear related to the amount of dissolved 3 ringed PAHs. The dispersant Corexit 9500 did not influence acute lethality of oil preparations. Embryonic oil exposure resulted in cardiotoxicity after 48 h, as evident from pericardial edema and reduced atrial contractility. Whereas pericardial edema appeared to correlate well with acute lethality at 96 h, atrial contractility did not. However, sub-lethal cardiotoxicity may impact long-term performance and survival. Dispersant did not affect the occurrence of pericardial edema; however, there was an apparent reduction in atrial contractility at 48 h of exposure. Pericardial edema at 48 h and lethality at 96 h were equally sensitive endpoints in mahi-mahi. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Toxicity, mechanism and health effects of some heavy metals

    Directory of Open Access Journals (Sweden)

    Jaishankar Monisha

    2014-06-01

    Full Text Available Heavy metal toxicity has proven to be a major threat and there are several health risks associated with it. The toxic effects of these metals, even though they do not have any biological role, remain present in some or the other form harmful for the human body and its proper functioning. They sometimes act as a pseudo element of the body while at certain times they may even interfere with metabolic processes. Few metals, such as aluminium, can be removed through elimination activities, while some metals get accumulated in the body and food chain, exhibiting a chronic nature. Various public health measures have been undertaken to control, prevent and treat metal toxicity occurring at various levels, such as occupational exposure, accidents and environmental factors. Metal toxicity depends upon the absorbed dose, the route of exposure and duration of exposure, i.e. acute or chronic. This can lead to various disorders and can also result in excessive damage due to oxidative stress induced by free radical formation. This review gives details about some heavy metals and their toxicity mechanisms, along with their health effects

  10. Effects of using synthetic sea salts when measuring and modeling copper toxicity in saltwater toxicity tests.

    Science.gov (United States)

    Arnold, W Ray; Cotsifas, Jeffrey S; Winter, Anna R; Klinck, Joel S; Smith, D Scott; Playle, Richard C

    2007-05-01

    Synthetic sea salts are often used to adjust the salinity of effluent, ambient, and laboratory water samples to perform toxicity tests with marine and estuarine species. The U.S. Environmental Protection Agency (U.S. EPA) provides guidance on salinity adjustment in its saltwater test guidelines. The U.S. EPA suggests using commercial sea salt brands, such as Forty Fathoms (now named Crystal Sea Marinemix, Bioassay Grade), HW Marinemix, or equivalent salts to adjust sample salinity. Toxicity testing laboratories in Canada and the United States were surveyed to determine synthetic sea salt brand preference. The laboratories (n = 27) reported using four brands: Crystal Sea Marinemix (56%), HW Marinemix (22%), Instant Ocean (11%), and Tropic Marin (11%). Saline solutions (30 g/L) of seven synthetic sea salts were analyzed for dissolved copper and dissolved organic carbon (DOC) content. Brands included those listed above plus modified general-purpose salt (modified GP2), Kent Marine, and Red Sea Salt. The synthetic sea salts added from analysis of variance, Tukey, alpha = 0.05, p copper toxicity. However, the measured dissolved copper effective concentration 50% (EC50) for Crystal Sea Marinemix was 9.7 microg Cu/L, similar to other tested sea salts. Analysis indicates that the organic matter in Crystal Sea Marinemix differs considerably from that of natural organic matter. On the basis of consistently adding little DOC and little dissolved copper, GP2 and Kent Marine are the best salts to use.

  11. Lithium Toxicity and Neurologic Effects: Probable Neuroleptic Malignant Syndrome Resulting from Lithium Toxicity

    Directory of Open Access Journals (Sweden)

    Osamede Edokpolo

    2012-01-01

    Full Text Available Introduction. We present the case of a patient who developed lithium toxicity with normal therapeutic levels, as a result of pharmacokinetic interaction with Valsartan, and probable Neuroleptic Malignant Syndrome from the ensuing lithium toxicity. Case Presentation. A 59-year old black male with bipolar disorder maintained on lithium and fluphenazine therapy presented with a 2 week history of worsening confusion, tremor, and gait abnormality. He recently had his dose of Valsartan increased. At presentation, patient had signs of autonomic instability, he was confused, dehydrated, and had rigidity of upper extremities. Significant labs on admission were lithium level-1.2, elevated CK-6008, leukocytosis WBC-22, and renal impairment; Creatinine-4.1, BUN-35, HCO3-20.1, and blood glucose 145. CT/MRI brain showed old cerebral infarcts, and there was no evidence of an infective process. Lithium and fluphenazine were discontinued, his lithium levels gradually decreased, and he improved with supportive treatment including rehydration and correction of electrolyte imbalance. Conclusions. This case illustrates that lithium toxicity can occur within therapeutic levels, and the neurotoxic effect of lithium can include Neuroleptic Malignant Syndrome. Clinicians should be aware of the risk associated with drug interactions with lithium.

  12. Immunotoxicological and histopathological effects of exposure to sublethal concentrations of mercuric chloride (HgCl^sub 2^) in red-bellied pacu (Piaractus brachypomus) ¤/Efectos inmunotoxicológicos e histopatológicos de la exposición a concentraciones subletales de cloruro de mercurio (HgCl^sub 2^) en cachama blanca (Piaractus brachypomus)/Avaliação imunotoxicológica e histopatológica da exposição a concentrações subletais de cloreto de mercúrio (HgCl^sub 2^) em Pirapitinga branca (Piaractus brachypomus)

    National Research Council Canada - National Science Library

    Juan S Naranjo-Gómez; Roberto Chacón-Novoa; Fabián Zambrano-Cardona; Fabián Uribe-García; Karol Ramírez; Julieth A Vargas-Morales; Iang S Rondón-Barragán

    2014-01-01

    ... between its content in water sources and mercury bioaccumulation in living organisms. This work assessed the immune and histopathological effects of exposure to sublethal concentrations of mercury chloride (HgCl^sub 2^) in Pacu...

  13. Toxic effects of polyethylene terephthalate microparticles and Di(2-ethylhexyl)phthalate on the calanoid copepod, Parvocalanus crassirostris.

    Science.gov (United States)

    Heindler, Franz M; Alajmi, Fahad; Huerlimann, Roger; Zeng, Chaoshu; Newman, Stephen J; Vamvounis, George; van Herwerden, Lynne

    2017-07-01

    Large amounts of plastic end up in the oceans every year where they fragment into microplastics over time. During this process, microplastics and their associated plasticizers become available for ingestion by different organisms. This study assessed the effects of microplastics (Polyethylene terephthalate; PET) and one plasticizer (Di(2-ethylhexyl)phthalate; DEHP) on mortality, productivity, population sizes and gene expression of the calanoid copepod Parvocalanus crassirostris. Copepods were exposed to DEHP for 48h to assess toxicity. Adults were very healthy following chemical exposure (up to 5120µg L-1), whereas nauplii were severely affected at very low concentrations (48h LC50value of 1.04 ng L-1). Adults exposed to sub-lethal concentrations of DEHP (0.1-0.3µg L-1) or microplastics (10,000-80,000 particles mL-1) exhibited substantial reductions in egg production. Populations were exposed to either microplastics or DEHP for 6 days with 18 days of recovery or for 24 days. Populations exposed to microplastics for 24 days significantly depleted in population size (60±4.1%, pplastic and DEHP treatments after 6 days of exposure, but not after 18 days of recovery. Hsp70-like expression showed to be unresponsive to either DEHP or microplastic exposure. Clearly, microplastics and plasticizers pose a serious threat to zooplankton and potentially to higher trophic levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Acute toxicity of cadmium in Anisops sardeus (Heteroptera:Notonectidae): Effects on adult and nymphal survival and swimming behavior.

    Science.gov (United States)

    Memtombi Chanu, Chongtham; Gupta, Susmita; Gupta, Abhik

    2017-11-01

    Adult female and male, and final instar nymph of Anisops sardeus (Heteroptera: Notonectidae) were exposed to graded concentrations of cadmium in 96h static-with-renewal acute toxicity tests, which were conducted in dry (March) and wet (May-June) seasons. The 96h LC50 values for instar V nymph, adult female and male were found to be 0.9, 0.59 and 0.51mgL-1 Cd, respectively, in wet season, while these were 26.7 and 20.2mgL-1 Cd for adult female and male, respectively, in dry season. Adult males were most sensitive to Cd, followed by females in both seasons, while highest tolerance in wet season was observed in instar V nymph. There was a steep decline in LC50 values from 24 to 96h in wet season. Besides mortality at higher concentrations of Cd, sublethal effects in terms of reduced 'velocity magnitude' (swimming speed) and mostly increased 'rotation angle' (turning angle) could be discerned at concentrations as low as 0.03mgL-1. The swimming pattern of Cd-exposed nymph and adults were also affected. Based on the bioaccumulation factor (BAF) values, A. sardeus could be designated as a macroconcentrator of Cd (BAF > 2), with highest Cd accumulation in instar V nymph, followed by that in female, and with lowest Cd accumulation in male. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Toxicity and life expectancy effects of Moringa oleifera seed extracts ...

    African Journals Online (AJOL)

    The toxicity and growth regulatory effects of Moringa oleifera seed extracts were assessed on third larval instars of Anopheles gambiae, under laboratory conditions. Mortality at different concentrations varied but increased as concentration level increased. Mortality progressed on daily bases throughout the period of ...

  16. Toxicity potentials and novelty-induced behavior effects of JEDDY ...

    African Journals Online (AJOL)

    Hence, the main objective of the research was to carry out scientific studies on its toxicity potentials as well as possible central effects. Twenty four albino rats of both sexes were obtained and divided into four groups (n=6 per group) for the administration of three dose levels of JEDDY decoction and the vehicle.

  17. Toxic Effects of Pollutants on Methane Production of River Sediment

    NARCIS (Netherlands)

    van Vlaardingen PLA; van Beelen P

    1992-01-01

    The effects of five compounds on the endogenous methane production of sediment samples of the river Rhine were examined. The concentrations of a toxicant that inhibited the methane production for 10% and 50% are called EC10 and EC50. Benzene, 1,2- dichloroethane, pentachlorophenol and chloroform

  18. Investigation of monocrotophos toxic effects on human lymphocytes ...

    African Journals Online (AJOL)

    Investigation of monocrotophos toxic effects on human lymphocytes at cytogenetic level. ... The analysis revealed that more satellite associations, breaks and gaps were found which were statistically significant (P < 0.05) when compared to controls. Comet assay was used to assess the possibility of monocrotophos ...

  19. The toxic effects of prolonged administration of chloramphenicol on ...

    African Journals Online (AJOL)

    The toxic effect of chloramphenicol on the liver and kidney was studied in laboratory Wistar rats. 16 adult rats of both sexes randomly divided into two groups were used. 10 animals in the test group were administered with chloramphenicol orally using rat cannula at human infant recommended dosage of 25mg/kg body ...

  20. Effect of Nitrogen Fertilizer on Micronutrients, Antinutrients and Toxic ...

    African Journals Online (AJOL)

    Pot experiments were conducted to study the effect of soil nitrogen levels on the antinutrient (oxalate), toxic substances (cyanide and nitrate) and some micronutrients (vitamin C, â-carotene) and mineral elements (Na, K, Mg, Ca, Zn, Fe,and Cu) in Vernonia amygdalina. Leaves of the vegetable were harvested at market ...

  1. Evaluation of toxic effects of metformin hydrochloride and ...

    African Journals Online (AJOL)

    Evaluation of toxic effects of metformin hydrochloride and glibenclamide on some organs of male rats. ... Twenty one rats were divided into three groups of seven rats each; group 1 served as control, groups 2 and 3 received GB and MET at doses of 5 and 30 mg/kg, respectively, for 21 days by oral gavage. Results indicate ...

  2. Health effects of toxicants: Online knowledge support

    Science.gov (United States)

    Judson, Richard; de Marcellus, Sally; de Knecht, Joop; Leinala, Eeva

    2016-01-01

    Research in toxicology generates vast quantities of data which reside on the Web and are subsequently appropriated and utilized to support further research. This data includes a broad spectrum of information about chemical, biological and radiological agents which can affect health, the nature of the effects, treatment, regulatory measures, and more. Information is structured in a variety of formats, including traditional databases, portals, prediction models, and decision making support tools. Online resources are created and housed by a variety of institutions, including libraries and government agencies. This paper focuses on three such institutions and the tools they offer to the public: the National Library of Medicine (NLM) and its Toxicology and Environmental Health Information Program, the United States Environmental Protection Agency (EPA), and the Organisation for Economic Co-operation and Development (OECD). Reference is also made to other relevant organizations. PMID:26506572

  3. Mercury and its toxic effects on fish

    Directory of Open Access Journals (Sweden)

    Patricia Morcillo

    2017-04-01

    Full Text Available Mercury (Hg and its derivative compounds have been parts of widespread pollutants of the aquatic environment. Since Hg is absorbed by fish and passed up the food chain to other fish-eating species, it does not only affect aquatic ecosystems but also humans through bioaccumulation. Thus, the knowledge of toxicological effects of Hg on fish has become one of the aims in research applied to fish aquaculture. Moreover, the use of alternative methods to animal testing has gained great interest in the field of Toxicology. This review addresses the systemic pathophysiology of individual organ systems associated with Hg poisoning on fish. Such data are extremely useful to the scientific community and public officials involved in health risk assessment and management of environmental contaminants as a guide to the best course of action to restore ecosystems and, in turn, to preserve human health.

  4. TOXIC EFFECTS OF CYPERMETHRIN IN FEMALE RABBITS

    Directory of Open Access Journals (Sweden)

    M. S. ULLAH, M. AHMAD, N. AHMAD, M. Z. KHAN1 AND I. AHMAD

    2006-10-01

    Full Text Available The aim of the present study was to explore the fetotoxic effects of cypermethrin (CY in female rabbits with low and high doses. For this purpose, 32 adult female rabbits were divided in to four equal groups A, B, C and D. Rabbits of groups A, B and C were treated with different levels of CY at the dose rate of 25, 50 and 75 mg/kg body weight intraperitoneally, while the group D served as a control and was given equal volume of normal saline intraperitoneally. The clinical signs exhibited by the rabbits treated with CY included salivation, licking of different body parts, muscular tremors, ataxia and convulsions. There was a significant difference in the numbers of CL and number of fetuses which mean the early embryonic death and post implantation loses at the high dose. There were microscopic changes in the ovaries and uteri of animals treated with CY.

  5. Sublethal and Reproductive Effects of Acute and Chronic Exposure to Flowback and Produced Water from Hydraulic Fracturing on the Water Flea Daphnia magna.

    Science.gov (United States)

    Blewett, Tamzin A; Delompré, Perrine L M; He, Yuhe; Folkerts, Erik J; Flynn, Shannon L; Alessi, Daniel S; Goss, Greg G

    2017-03-07

    Hydraulic fracturing is an industrial process allowing for the extraction of gas or oil. To fracture the rocks, a proprietary mix of chemicals is injected under high pressure, which later returns to the surface as flowback and produced water (FPW). FPW is a complex chemical mixture consisting of trace metals, organic compounds, and often, high levels of salts. FPW toxicity to the model freshwater crustacean Daphnia magna was characterized utilizing acute (48 h median lethal concentrations; LC50) and chronic (21 day) exposures. A decrease in reproduction was observed, with a mean value of 18.5 neonates produced per replicate over a 21 day chronic exposure to 0.04% FPW, which was a significant decrease from the average of 64 neonates produced in the controls. The time to first brood was delayed in the highest FPW (0.04%) treatment. Neonates exhibited an LC50 of 0.19% of full-strength FPW, making them more sensitive than adults, which displayed an LC50 value of 0.75%. Quantitative PCR highlighted significant changes in expression of genes encoding xenobiotic metabolism (cyp4) and moulting (cut). This study is the first to characterize chronic FPW toxicity and will help with the development of environmental monitoring and risk assessment of FPW spills.

  6. Effects of elevated temperature on the toxicity of copper and oxytetracycline in the marine model, Euplotes crassus: a climate change perspective.

    Science.gov (United States)

    Gomiero, A; Viarengo, A

    2014-11-01

    Trace metals and broad-spectrum antibiotic drugs are common environmental contaminants, the importance of which is increasing due to global climate change-related effects. In the present study, the biological model organism E. crassus was first acclimated to five temperatures, from 25 °C to 33 °C, followed by exposure to nominal concentrations of copper, the antibiotic model compound oxytetracycline and mixtures of both, at increasing thermal conditions. Variations of temperature-related toxicity were assessed by two high-level endpoint tests, survival and replication rates, and two sublethal parameters: endocytosis rate and lysosomal membrane stability. The selected toxicants presented opposite behaviours as the protozoa's survival rates increased following an increasing thermal gradient in the oxytetracycline-related treatments, and a decline of tolerance in metal-related treatments was observed. Results of tests combining binary mixtures of tested toxicants showed a complex pattern of responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Is folklore use of Euphorbia helioscopia devoid of toxic effects?

    Science.gov (United States)

    Saleem, Uzma; Ahmad, Bashir; Ahmad, Mobasher; Erum, Alia; Hussain, Khalid; Irfan Bukhari, Nadeem

    2016-01-01

    To evaluate acute toxic effects of Euphorbia helioscopia in order to assure the safety and usefulness of herbal remedy. The Organization for Economic Cooperation and Development (OECD) for chemical testing guidelines No. 425 for acute oral toxicity testing were followed in this study. Mice were divided into three groups (n = 5). Group I served as control. Groups II and III were administered methanol extract of E. helioscopia leaves and latex orally at dose of 2000 mg/kg, respectively. Then, all the animals were observed for two weeks. Blood sampling was done by cardiac puncture after 14 days from each group for biochemical analysis. Histopathology was performed to find out any microscopic lesion in vital organs. LD50 was found greater than 2000 mg/kg. There was decrease in cholesterol, triglycerides, LDL and VLDL levels of latex and leaves with methanol extract-treated animals, with respect to control indicating plant's hypolipidemic effect. On macroscopic examination, no lesions were found on vital organs, such as liver, heart and kidney; and normal architecture was observed on microscopic examination. On the basis of results, it was concluded that methanol extract of E. helioscopia leaves and latex were devoid of toxic effects in acute toxicity study.

  8. Sublethal Dosage of Imidacloprid Reduces the Microglomerular Density of Honey Bee Mushroom Bodies

    Science.gov (United States)

    Peng, Yi-Chan; Yang, En-Cheng

    2016-01-01

    The dramatic loss of honey bees is a major concern worldwide. Previous studies have indicated that neonicotinoid insecticides cause behavioural abnormalities and have proven that exposure to sublethal doses of imidacloprid during the larval stage decreases the olfactory learning ability of adults. The present study shows the effect of sublethal doses of imidacloprid on the neural development of the honey bee brain by immunolabelling synaptic units in the calyces of mushroom bodies. We found that the density of the synaptic units in the region of the calyces, which are responsible for olfactory and visual functions, decreased after being exposed to a sublethal dose of imidacloprid. This not only links a decrease in olfactory learning ability to abnormal neural connectivity but also provides evidence that imidacloprid damages the development of the nervous system in regions responsible for both olfaction and vision during the larval stage of the honey bee. PMID:26757950

  9. Sub-lethal antibiotic treatment leads to multidrug resistance via radical-induced mutagenesis

    Science.gov (United States)

    Kohanski, Michael A.; DePristo, Mark A.; Collins, James J.

    2010-01-01

    Summary Antibiotic resistance arises through mechanisms such as selection of naturally occurring resistant mutants and horizontal gene transfer. Recently, oxidative stress has been implicated as one of the mechanisms whereby bactericidal antibiotics kill bacteria. Here we show that sub-lethal levels of bactericidal antibiotics induce mutagenesis, resulting in heterogeneous increases in the minimum inhibitory concentration for a range of antibiotics, irrespective of the drug target. This increase in mutagenesis correlates with an increase in ROS, and is prevented by the ROS scavenger thiourea and by anaerobic conditions, indicating that sub-lethal concentrations of antibiotics induce mutagenesis by stimulating the production of ROS. We demonstrate that these effects can lead to mutant strains that are sensitive to the applied antibiotic but resistant to other antibiotics. This work establishes a radical-based molecular mechanism whereby sub-lethal levels of antibiotics can lead to multidrug resistance, which has important implications for the widespread use and misuse of antibiotics. PMID:20159551

  10. POTENTIAL PATHOPHYSIOLOGICAL MECHANISMS OF ULTRAFINE PARTICLE TOXIC EFFECTS IN HUMANS

    Directory of Open Access Journals (Sweden)

    JASMINA JOVIĆ-STOŠIĆ

    2008-03-01

    Full Text Available Epidemiological and clinical studies suggested the association of the particulate matter ambient air pollution and the increased morbidity and mortality, mainly from respiratory and cardiovascular diseases. The size of particles has great influence on their toxicity, because it determines the site in the respiratory tract where they deposit. The most well established theory explaining the mechanisms behind the increased toxicity of ultrafine particles (UFP, < 0.1 µm is that it has to do with the increased surface area and/or the combination with the increased number of particles. Biological effects of UFP are also determined by their shape and chemical composition, so it is not possible to estimate their toxicity in a general way. General hypothesis suggested that exposure to inhaled particles induces pulmonary alveolar inflammation as a basic pathophysiological event, triggering release of various proinflammatory cytokines. Chronic inflammation is a very important underlying mechanism in the genesis of atherosclerosis and cardiovascular diseases. UFP can freely move through the circulation, but their effects on the secondary organs are not known yet, so more studies on recognizing toxicological endpoints of UFP are needed. Determination of UFP toxicity and the estimation of their internal and biologically active dose are necessary for the evidence based conclusions connecting air pollution by UFP and human diseases.

  11. The fungicide mancozeb induces toxic effects on mammalian granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Paro, Rita [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Tiboni, Gian Mario [Department of Medicine and Aging, Section of Reproductive Sciences, University “G. D' Annunzio”, Chieti-Pescara (Italy); Buccione, Roberto [Tumor Cell Invasion Laboratory, Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti (Italy); Rossi, Gianna; Cellini, Valerio [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Canipari, Rita [Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Section of Histology and Embryology, School of Pharmacy and Medicine, “Sapienza” University of Rome, Rome (Italy); Cecconi, Sandra, E-mail: sandra.cecconi@cc.univaq.it [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy)

    2012-04-15

    The ethylene-bis-dithiocarbamate mancozeb is a widely used fungicide with low reported toxicity in mammals. In mice, mancozeb induces embryo apoptosis, affects oocyte meiotic spindle morphology and impairs fertilization rate even when used at very low concentrations. We evaluated the toxic effects of mancozeb on the mouse and human ovarian somatic granulosa cells. We examined parameters such as cell morphology, induction of apoptosis, and p53 expression levels. Mouse granulosa cells exposed to mancozeb underwent a time- and dose-dependent modification of their morphology, and acquired the ability to migrate but not to proliferate. The expression level of p53, in terms of mRNA and protein content, decreased significantly in comparison with unexposed cells, but no change in apoptosis was recorded. Toxic effects could be attributed, at least in part, to the presence of ethylenthiourea (ETU), the main mancozeb catabolite, which was found in culture medium. Human granulosa cells also showed dose-dependent morphological changes and reduced p53 expression levels after exposure to mancozeb. Altogether, these results indicate that mancozeb affects the somatic cells of the mammalian ovarian follicles by inducing a premalignant-like status, and that such damage occurs to the same extent in both mouse and human GC. These results further substantiate the concept that mancozeb should be regarded as a reproductive toxicant. Highlights: ► The fungicide mancozeb affects oocyte spindle morphology and fertilization rate. ► We investigated the toxic effects of mancozeb on mouse and human granulosa cells. ► Granulosa cells modify their morphology and expression level of p53. ► Mancozeb induces a premalignant-like status in exposed cells.

  12. Toxic effects of ethanol on bovine serum albumin.

    Science.gov (United States)

    Liu, Rutao; Qin, Pengfei; Wang, Li; Zhao, Xingchen; Liu, Yihong; Hao, Xiaopeng

    2010-01-01

    The toxic effects of ethanol on bovine serum albumin (BSA) were measured by resonance light scattering (RLS), fluorescence spectroscopy, ultraviolet spectrophotometry (UV), circular dichroism (CD), and transmission electron microscopy (TEM). The results indicated that ethanol had toxic effects on BSA, which led to protein denaturation and the effects increased with the ethanol dose. By means of RLS, BSA was found to aggregate in the presence of ethanol and particles smaller than 100 nm were observed from TEM. The fluorescence spectra showed that the intensity of the characteristic peak of BSA decreased and blue shifted, because of changes in the BSA skeleton structure, as well as alteration of the microenvironment of tryptophan (Trp) residues. The conformation changes of BSA were also shown by UV and CD spectrometry.

  13. Functional modifications of macrophage activity after sublethal irradiation. [Toxoplasma gondii

    Energy Technology Data Exchange (ETDEWEB)

    Swartz, R.P.

    1982-01-01

    The modifications of macrophage activity following sublethal irradiation, both in vivo and in vitro, were studied using spreading and C3b-receptor-mediated ingestion assays. Nonelicited peritoneal washout cells were examined for changes in activity and selected population characteristics. The cells from irradiated mice were from a resident peritoneal population and not immigrating cells. The macrophage population showed enhanced activity early with a refractory period (24-48) when the macrophages were unresponsive to stimulation by irradiated lymphocytes. The enhanced activity was inversely dose dependent on macrophage. The lymphocytes showed a regulatory function(s) on the time post irradiation at which they were examined. Early lymphocytes exhibited the ability to enhance the activity of normal macrophages while lymphocytes removed 24 hours post irradiation could suppress the activity of already activated macrophages. The effect(s) of the various lymphocyte populations were reproduced with cell-free supernatants which was indicative of the production of lymphokines. Separation on nylon wool columns indicated that the activity resided primarily in the T-cell population of lymphocytes. In vitro irradiation indicated that stimulation of the lymphocytes is macrophage dependent. Additional work indicated that sublethally irradiated macrophages did not inhibit replication of the coccidian protozoon Toxoplasma gondii although they did show increased phagocytosis. Examination of the serum from whole body irradiated mice showed the presence of a postirradiation substance which enhanced the phagocytosis of normal macrophages. It was not present in the serum of normal mice and was not endotoxin.

  14. [Acute Toxic Effects of Bromate on Aquatic Organisms].

    Science.gov (United States)

    Wang, Zhi-wei; Liu, Dong-mei; Zhang, Wen-juan; Cui, Fu-yi

    2016-02-15

    Acute toxic effects of potassium bromate, sodium bromate and potassium bromide on luminescent bacteria, water flea, green alga and zebrafish were studied using standard toxic testing methods. The results showed that the pollutants had no effect on the luminous intensity of luminescent bacteria. The 96 h EC5. of potassium bromate on Scenedesmus obliquus was 738.18 mg x L(-1), 48 h EC50 on Daphnia magna and Moina was 154.01 mg x L(-1) was 161.80 mg x L(-1), while 48 h LC50 was 198 52 mg x L(-1), 175.68 mg x L(-1), and 96 h LC50 on zebrafish was 931.4 mg x L(-1). The 96 h EC50 of sodium bromate on Scenedesmus obliquus was 540.26 mg x L(-1), 48 h EC50 Daphnia magna and Moina was 127.90 mg x L(-1), 111.07 mg x L(-1), while 48 h LC50 was 161.80 mg x L(-1), 123.47 mg x L(-1), and 96 h LC50 on zebrafish was 1065.6 mg x L(-1). But the effects of potassium bromide on the above several kinds of aquatic organisms were far smaller than those of potassium bromate and sodium bromate. The toxic effects on test organisms were due to the impacts of bromate after the comparison of different pollutants, and the effects were more obvious with the increase of exposure time. The order of sensitivity to the toxic effects of bromate was Daphnia magna, Moina > Scenedesmus obliquus > zebrafish > Chlorella vulgaris, luminescent bacteria.

  15. Effect of Shodhana Treatment on Chronic Toxicity and Recovery of Aconite

    Science.gov (United States)

    Sarkar, P.K.; Prajapati, P.K.; Shukla, V.J.; Ravishankar, B.

    2012-01-01

    Aconite is one of the poisonous plants used therapeutically in practice of Ayurveda after proper treatment called as ‘Shodhana’. To determine the effect of Shodhana treatment on chronic toxicity and to assess the effect of recovery period after chronic toxicity of aconite. Raw aconite (RV), urine treated aconite (SM), and milk treated aconite (SD) were administered in 6.25 mg/kg dose in Charles Foster strain albino rats for 90 days for chronic toxicity. Six rats from each were kept for another 30 days without test drugs treatment to observe recovery from chronic toxicity. RV was found to be highly toxic in chronic exposure, SM had no apparent toxicity, but SD had mild toxicity in kidney. The toxicities of RV and SD were reversible, but sudden withdrawal of SM caused adverse effects, suggestive of tapering withdrawal. Shodhana treatments remove toxic effects from raw aconite. Chronic toxicity of aconite is reversible. Confirmed the arrangement of abstract PMID:22736901

  16. Toxic effects of systemic cisplatin on rat eyes and the protective effect of hesperidin against this toxicity.

    Science.gov (United States)

    Polat, Nihat; Ciftci, Osman; Cetin, Aslı; Yılmaz, Turgut

    2016-03-01

    In the present study, cisplatin (CP) induced eye toxicity and the beneficial effect of hesperidin (HP) was investigated. Twenty-eight rats were equally divided into four groups; the first group was kept as control. In the second and third group, CP and HP were given at the doses of 7 mg/kg and 50 mg/kg/d, respectively. In the fourth group, CP and HP were given together at the same doses. Tissue samples were collected on day 14 of CP treatment. The results demonstrated that CP caused a significant increase in thiobarbituric acid reactive substances (TBARS) levels and decrease of glutathione levels and antioxidant enzyme activity (catalase, superoxide dismutase and glutathione peroxidase) in eye tissues compared to other groups, HP prevented these effects of CP. Besides, CP led to histopathological damage in the retina and cornea. On the other hand, HP treatment prevented histopathological effects of CP. CP had severe dose-limiting toxic effects and HP treatment can be beneficial against the toxic ocular effects of CP. Thus, it appears that co-administration of HP with CP may be a useful approach to attenuate the negative effects of CP on the eye.

  17. Toxic effect of carica papaya bark on body weight, haematology

    African Journals Online (AJOL)

    Chibuike

    Toxic effect of carica papaya bark on body weight, haematology, and some biochemical parameters. M.K.C. Duru*1, B. A.Amadi2, C.T.Amadi3, K.C.Lele2, J. C.Anudike4, O.R.Chima-Ezika1, K. Osuocha1. 1Department of Biochemistry, Abia State University, Uturu, Abia State, Nigeria; 2Department of Biochemistry, Imo State ...

  18. The toxicity effect of selected drugs in animals

    OpenAIRE

    HUNCHAK V.M.; HUFRIY D.F.; MASLIANKO R.P.; HUTІY B.V.; LEVKIVSKY D.M.; LEVKIVSKA N.D.; STORCHAK Y.G.

    2014-01-01

    Therapeutic products quite often are causes of poisoning in both small and large animals. Drug poisonings in animals occur commonly due to off-label use of medicines, wrong dosage, negligence, accidental ingestion and deliberate poisonings. Toxicity of veterinary drugs may become evident also in therapeutic doses when adverse effects may occur. The aim of this review is to inform veterinary specialists about both veterinary and human drugs, specifically antiparasitics, non-steroidal anti-infl...

  19. EFFECTS OF SILICON ON ALLEVIATING ARSENIC TOXICITY IN MAIZE PLANTS

    Directory of Open Access Journals (Sweden)

    Airon José da Silva

    2015-02-01

    Full Text Available Arsenic is a metalloid highly toxic to plants and animals, causing reduced plant growth and various health problems for humans and animals. Silicon, however, has excelled in alleviating stress caused by toxic elements in plants. The aim of this study was to investigate the effects of Si in alleviating As stress in maize plants grown in a nutrient solution and evaluate the potential of the spectral emission parameters and the red fluorescence (Fr and far-red fluorescence (FFr ratio obtained in analysis of chlorophyll fluorescence in determination of this interaction. An experiment was carried out in a nutrient solution containing a toxic rate of As (68 μmol L-1 and six increasing rates of Si (0, 0.25, 0.5, 1.0, 1.5, and 2.0 mmol L-1. Dry matter production and concentrations of As, Si, and photosynthetic pigments were then evaluated. Chlorophyll fluorescence was also measured throughout plant growth. Si has positive effects in alleviating As stress in maize plants, evidenced by the increase in photosynthetic pigments. Silicon application resulted in higher As levels in plant tissue; therefore, using Si for soil phytoremediation may be a promising choice. Chlorophyll fluorescence analysis proved to be a sensitive tool, and it can be successfully used in the study of the ameliorating effects of Si in plant protection, with the Fr/FFr ratio as the variable recommended for identification of temporal changes in plants.

  20. Protective Effect of Silybin in Rats Liver Toxicity

    Directory of Open Access Journals (Sweden)

    Roxana Popescu

    2010-05-01

    Full Text Available Silybin is a flavonoid extracted from the herb Armurariu (Silybum marianum and has the potential efficacy in the treatment of liver disease. The aims of this study were to investigate the effect of alcohol and CCl4 on liver histology and the capacity of silybin to ameliorate the hepatotoxicity. Thirty adult male Wistar rats were used in the study. Liver toxicity was induced by dietary alcohol administration and CCl4 intra-peritoneal injection. The protective effect of silibin was investigated by co-administration of silybin with these toxic agents. Hepatocellular and extracellular matrix integrity was determined by histopathological and immunohistochemical study. Hematoxylin- Eosin and trichrome stains sections were studied in each case. For immunohistochemistry we used monoclonal anticollagen IV primary antibody. Light microscopic evaluation of liver tissues shows that control and silibin treated groups has normal liver structure. In the toxicity groups, HE and trichromic staining showed hepatocellular necrosis, inflammatory infiltrate and proliferating collagen fibers. Immunoexpression of collagen IV was variable. In the control group, we found negative expression. Collagen IV displays positive immunoreaction in hepatotoxicity groups, at the level of the areas rich in inflammatory infiltrate and with degenerative aspect. After this study, we can conclude that silybin, in rats, has protective effects.

  1. Aquatic toxicity of PAHs and PAH mixtures at saturation to benthic amphipods: Linking toxic effects to chemical activity

    Energy Technology Data Exchange (ETDEWEB)

    Engraff, Maria [Department of Marine Ecology, National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, 4000 Roskilde (Denmark); Solere, Clementine; Smith, Kilian E.C.; Mayer, Philipp [Department of Environmental Chemistry and Microbiology, National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, 4000 Roskilde (Denmark); Dahlloef, Ingela, E-mail: ind@dmu.dk [Department of Marine Ecology, National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, 4000 Roskilde (Denmark)

    2011-04-15

    Organisms in marine sediments are usually exposed to mixtures of polycyclic aromatic hydrocarbons (PAHs), whereas risk assessment and management typically focus on the effects of single PAHs. This can lead to an underestimation of risk if the effects of single compounds are additive or synergistic. Because of the virtually infinite number of mixture-combinations, and the many different targeted organisms, it would be advantageous to have a model for the assessment of mixture effects. In this study we tested whether chemical activity, which drives the partitioning of PAHs into organisms, can be used to model the baseline toxicity of mixtures. Experiments were performed with two benthic amphipod species (Orchomonella pinguis and Corophium volutator), using passive dosing to control the external exposure of single PAHs and mixtures of three and four PAHs. The baseline toxicity of individual PAHs at water saturation generally increased with increasing chemical activity of the PAHs. For O. pinguis, the baseline toxicity of PAH mixtures was successfully described by the sum of chemical activities. Some compounds and mixtures showed a delayed expression of toxicity, highlighting the need to adjust the length of the experiment depending on the organism. On the other hand, some of the single compounds had a higher toxicity than expected, possibly due to the toxicity of PAH metabolites. We suggest that chemical activity of mixtures can, and should, be used in addition to toxicity data for single compounds in environmental risk assessment.

  2. Aquatic toxicity of PAHs and PAH mixtures at saturation to benthic amphipods: linking toxic effects to chemical activity.

    Science.gov (United States)

    Engraff, Maria; Solere, Clémentine; Smith, Kilian E C; Mayer, Philipp; Dahllöf, Ingela

    2011-04-01

    Organisms in marine sediments are usually exposed to mixtures of polycyclic aromatic hydrocarbons (PAHs), whereas risk assessment and management typically focus on the effects of single PAHs. This can lead to an underestimation of risk if the effects of single compounds are additive or synergistic. Because of the virtually infinite number of mixture-combinations, and the many different targeted organisms, it would be advantageous to have a model for the assessment of mixture effects. In this study we tested whether chemical activity, which drives the partitioning of PAHs into organisms, can be used to model the baseline toxicity of mixtures. Experiments were performed with two benthic amphipod species (Orchomonella pinguis and Corophium volutator), using passive dosing to control the external exposure of single PAHs and mixtures of three and four PAHs. The baseline toxicity of individual PAHs at water saturation generally increased with increasing chemical activity of the PAHs. For O. pinguis, the baseline toxicity of PAH mixtures was successfully described by the sum of chemical activities. Some compounds and mixtures showed a delayed expression of toxicity, highlighting the need to adjust the length of the experiment depending on the organism. On the other hand, some of the single compounds had a higher toxicity than expected, possibly due to the toxicity of PAH metabolites. We suggest that chemical activity of mixtures can, and should, be used in addition to toxicity data for single compounds in environmental risk assessment. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. The effects of carbamate pesticide on fish in freshwater ecosystems ...

    African Journals Online (AJOL)

    Vetox 85R is also applied on ponds and stagnant water purposely to control aquatic insects. Research reports reveal chronic and acute toxic effects of this chemical on fish and fish food. The deleterious effects of sublethal concentrations of carbaryl on fish during spawning period include rupture of blood vessels supplying ...

  4. Lima bean lady beetle interactions: spider mite mediates sublethal effects of its host plant on growth and development of its predator

    Science.gov (United States)

    Cultivated plants can have negative effects on natural enemies that attack spider mites. In this study, we tested the hypothesis that spider mites mediate effects of a lima bean, Phaseolus lunatus L., cultivar on the life history of a lady beetle Stethorus punctillum Weise. We provisioned laborato...

  5. Effects of calcium at toxic concentrations of cadmium in plants.

    Science.gov (United States)

    Huang, Danlian; Gong, Xiaomin; Liu, Yunguo; Zeng, Guangming; Lai, Cui; Bashir, Hassan; Zhou, Lu; Wang, Dafei; Xu, Piao; Cheng, Min; Wan, Jia

    2017-05-01

    This review provides new insight that calcium plays important roles in plant growth, heavy metal accumulation and translocation, photosynthesis, oxidative damage and signal transduction under cadmium stress. Increasing heavy metal pollution problems have raised word-wide concerns. Cadmium (Cd), being a highly toxic metal, poses potential risks both to ecosystems and human health. Compared with conventional technologies, phytoremediation, being cost-efficient, highly stable and environment-friendly, is believed to be a promising green technology for Cd decontamination. However, Cd can be easily taken up by plants and may cause severe phytotoxicity to plants, thus limiting the efficiency of phytoremediation. Various researches are being done to investigate the effects of exogenous substances on the mitigation of Cd toxicity to plants. Calcium (Ca) is an essential plant macronutrient that involved in various plant physiological processes, such as plant growth and development, cell division, cytoplasmic streaming, photosynthesis and intracellular signaling transduction. Due to the chemical similarity between Ca and Cd, Ca may mediate Cd-induced physiological or metabolic changes in plants. Recent studies have shown that Ca could be used as an exogenous substance to protect plants against Cd stress by the alleviation of growth inhibition, regulation of metal uptake and translocation, improvement of photosynthesis, mitigation of oxidative damages and the control of signal transduction in the plants. The effects of Ca on toxic concentrations of Cd in plants are reviewed. This review also provides new insight that plants with enhanced Ca level have improved resistance to Cd stress.

  6. Effects of physicochemical properties of nanomaterials on their toxicity.

    Science.gov (United States)

    Li, Xiaoming; Liu, Wei; Sun, Lianwen; Aifantis, Katerina E; Yu, Bo; Fan, Yubo; Feng, Qingling; Cui, Fuzhai; Watari, Fumio

    2015-07-01

    Due to their unique size and properties, nanomaterials have numerous applications, which range from electronics, cosmetics, household appliances, energy storage, and semiconductor devices, to medical products such as biological sensors, drug carriers, bioprobes, and implants. Many of the promising properties of nanomaterials arise from their large surface to volume ratio and, therefore, nanobiomaterials that are implantable have a large contact area with the human body. Before, therefore, we can fully exploit nanomaterials, in medicine and bioengineering; it is necessary to understand how they can affect the human body. As a step in this direction, this review paper provides a comprehensive summary of the effects that the physicochemical properties of commonly used nanobiomaterials have on their toxicity. Furthermore, the possible mechanisms of toxicity are described with the aim to provide guidance concerning the design of the nanobiomaterials with desirable properties. © 2014 Wiley Periodicals, Inc.

  7. Chlorpyrifos chronic toxicity in broilers and effect of vitamin C

    Directory of Open Access Journals (Sweden)

    A.M. Kammon

    2011-02-01

    Full Text Available An experiment was conducted to study chlorpyrifos chronic toxicity in broilers and the protective effect of vitamin C. Oral administration of 0.8 mg/kg body weight (bw (1/50 LD50 chlorpyrifos (Radar®, produced mild diarrhea and gross lesions comprised of paleness, flaccid consistency and slightly enlargement of liver. Histopathologically, chlorpyrifos produced degenerative changes in various organs. Oral administration of 100 mg/kg bw vitamin C partially ameliorated the degenerative changes in kidney and heart. There was insignificant alteration in biochemical and haematological profiles. It is concluded that supplementation of vitamin C reduced the severity of lesions induced by chronic chlorpyrifos toxicity in broilers.

  8. (1)H NMR-based metabolomics of Daphnia magna responses after sub-lethal exposure to triclosan, carbamazepine and ibuprofen.

    Science.gov (United States)

    Kovacevic, Vera; Simpson, André J; Simpson, Myrna J

    2016-09-01

    Pharmaceuticals and personal care products are a class of emerging contaminants that are present in wastewater effluents, surface water, and groundwater around the world. There is a need to determine rapid and reliable bioindicators of exposure and the toxic mode of action of these contaminants to aquatic organisms. (1)H nuclear magnetic resonance (NMR)-based metabolomics in combination with multivariate statistical analysis was used to determine the metabolic profile of Daphnia magna after exposure to a range of sub-lethal concentrations of triclosan (6.25-100μg/L), carbamazepine (1.75-14mg/L) and ibuprofen (1.75-14mg/L) for 48h. Sub-lethal triclosan exposure suggested a general oxidative stress condition and the branched-chain amino acids, glutamine, glutamate, and methionine emerged as potential bioindicators. The aromatic amino acids, serine, glycine and alanine are potential bioindicators for sub-lethal carbamazepine exposure that may have altered energy metabolism. The potential bioindicators for sub-lethal ibuprofen exposure are serine, methionine, lysine, arginine and leucine, which showed a concentration-dependent response. The differences in the metabolic changes were related to the dissimilar modes of toxicity of triclosan, carbamazepine and ibuprofen. (1)H NMR-based metabolomics gave an improved understanding of how these emerging contaminants impact the keystone species D. magna. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Sublethal red tide toxin exposure in free-ranging manatees (Trichechus manatus) affects the immune system through reduced lymphocyte proliferation responses, inflammation, and oxidative stress.

    Science.gov (United States)

    Walsh, Catherine J; Butawan, Matthew; Yordy, Jennifer; Ball, Ray; Flewelling, Leanne; de Wit, Martine; Bonde, Robert K

    2015-04-01

    The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected by exposure to blooms of the toxic dinoflagellate, Karenia brevis. K. brevis blooms are common in manatee habitats of Florida's southwestern coast and produce a group of cyclic polyether toxins collectively referred to as red tide toxins, or brevetoxins. Although a large number of manatees exposed to significant levels of red tide toxins die, several manatees are rescued from sublethal exposure and are successfully treated and returned to the wild. Sublethal brevetoxin exposure may potentially impact the manatee immune system. Lymphocyte proliferative responses and a suite of immune function parameters in the plasma were used to evaluate effects of brevetoxin exposure on health of manatees rescued from natural exposure to red tide toxins in their habitat. Blood samples were collected from rescued manatees at Lowry Park Zoo in Tampa, FL and from healthy, unexposed manatees in Crystal River, FL. Peripheral blood leukocytes (PBL) isolated from whole blood were stimulated with T-cell mitogens, ConA and PHA. A suite of plasma parameters, including plasma protein electrophoresis profiles, lysozyme activity, superoxide dismutase (SOD) activity, and reactive oxygen/nitrogen (ROS/RNS) species, was also used to assess manatee health. Significant decreases (p<0.05) in lymphocyte proliferation were observed in ConA and PHA stimulated lymphocytes from rescued animals compared to non-exposed animals. Significant correlations were observed between oxidative stress markers (SOD, ROS/RNS) and plasma brevetoxin concentrations. Sublethal exposure to brevetoxins in the wild impacts some immune function components, and thus, overall health, in the Florida manatee. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. The effects of sublethal and lethal doses of ivermectin on the reproductive physiology and larval development of the dung beetle Euoniticellus intermedius (Coleoptera: Scarabaeidae)

    National Research Council Canada - National Science Library

    Imelda Martínez M; Jean-Pierre Lumaret; Rosario Ortiz Zayas; Nassera Kadiri

    2017-01-01

    This study assesses the effects of the veterinary medical product ivermectin (IVM) in a range of concentrations on adult reproductive physiology and larval mortality of the dung beetle Euoniticellus intermedius...

  11. Effects of benzoic acid and cadmium toxicity on wheat seedlings

    Directory of Open Access Journals (Sweden)

    Kavita Yadav

    2013-06-01

    Full Text Available Benzoic acid (BA and Cd exhibit cumulative effects on plants due to their accumulation in the soil. The present study reports the effects of BA an allelochemical, Cd and their combinations on seed germination, seedling growth, biochemical parameters, and response of antioxidant enzymes in Triticum aestivum L. The experiment was conducted in sand supplemented with Hoagland nutrient solution. Benzoic acid was applied at concentrations of 0.5, 1.0, and 1.5 mM with or without Cd (7 mg L-1 to observe effects of allelochemical and Cd alone and in combination on wheat. Both stresses exhibited inhibitory effect on growth and metabolism of wheat seedlings. The allelochemical in single and combined treatments with Cd decreased seedling growth as compared to Cd stress. The two stresses significantly enhanced malondialdehyde content of wheat seedlings. The activity of other antioxidant enzymes, viz. superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX, and guaiacol peroxidase (POX were also recorded. SOD increased in seedlings under the two stresses. CAT more prominently ameliorates the toxic effects of H2O2 as compared with APX and POX and protected wheat seedlings from oxidative stress. Allelochemical buttressed the toxic effect of Cd on wheat seedlings.

  12. Effects of Short-Term Exposure to Sublethal Concentrations of Silver Nanoparticles on Histopathology and Electron Microscope Ultrastructure of Zebrafish (Danio Rerio Gills

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    Borhan Mansouri

    2015-11-01

    Full Text Available Background: The increasing use of nanomaterials and nanoproducts has increased the possibility of contamination of the environment, which may have adverse effects on different organisms. The aim of this study was to evaluate the effects of silver nanoparticles on histopathology and gill ultrastructure of zebrafish (Danio rerio under laboratory conditions. Methods: Zebrafish were exposed to four concentrations of silver nanoparticles (0.0015, 0.00375, 0.0075, and 0.015 mg/l for a period of 4 days. Gill ultrastructure and histopathological changes were studied using scanning electron microscope and haematoxylin - eosin staining. Results: Exposure to silver nanoparticles significantly (P < 0.001 increased the diameter of gill filaments and secondary lamellae, while silver nanoparticles significantly reduced the length of the secondary gills in zebrafish. Moreover, other changes such as vacuolization, dilated and clubbed tips, hyperplasia, edema, fusion, swelling of mucocytes, hypertrophy, and necrosis were observed. The effects of silver nanoparticles in zebrafish gills were dose dependent. Conclusion: Based on the adverse effects of AgNPs on zebrafish gills, silver nanoparticle solutions can be hazardous pollutants for the environment.

  13. Toxic effects of nanomaterial-adsorbed cadmium on Daphnia magna.

    Science.gov (United States)

    Gao, Minling; Zhang, Ze; Lv, Mengting; Song, Wenhua; Lv, Yuhua

    2018-02-01

    Chemical immobilization technologies involving the use of chemical absorbents such as nanomaterials have been recommended for the remediation of Cd-contaminated water and soil. The impact of nanomaterials or nanomaterials coexisting with other contaminants on aquatic organisms has been reported, but information on the toxic effects of nanomaterial-adsorbed cadmium (Nano-Cd) on aquatic organisms is lacking. This study aimed to investigate the acute and sub-acute toxicity of Nano-Cd on Daphnia magna by using a method developed based on the standard Organisation for Economic Co-operation and Development (OECD) 202 guidelines. The toxicity of cadmium chloride (Cd 2+ ), nano-manganese dioxide-cadmium (nMnO 2 -Cd), 20nm nano-hydroxyapatite-cadmium (nHAP 20 -Cd), and 40nm nano-hydroxyapatite-cadmium (nHAP 40 -Cd) to D. magna was in the following order: Cd 2+ > nMnO 2 -Cd > nHAP 20 -Cd > nHAP 40 -Cd. Further, nMnO 2 -Cd, nHAP 20 -Cd, and nHAP 40 -Cd showed acute toxicity to D. magna of level II grade according to the Commission of the European Communities and OECD standards. Exposure to low and medium, but not high, Nano-Cd concentrations increased the activities of peroxidase, superoxide dismutase, catalase, and anti-superoxide anion. Thus, Nano-Cd, particularly at high concentrations, could exert oxidative damage in D. magna. An increase in Cd 2+ and Nano-Cd concentrations gradually increased the malondialdehyde content, indicating cell membrane damage caused by the production of excessive O 2 - . Thus, the use of nanomaterials after adsorption of Cd is associated with a potential risk to aquatic organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Toxicity of the Herbicide Atrazine: Effects on Lipid Peroxidation and Activities of Antioxidant Enzymes in the Freshwater Fish Channa Punctatus (Bloch

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    Satish Kumar Srivastava

    2010-08-01

    Full Text Available The present study was undertaken to evaluate the toxicity and effects of a commercial formulation of the herbicide atrazine (Rasayanzine on lipid peroxidation and antioxidant enzyme system in the freshwater air breathing fish Channa punctatus. The 12, 24, 48, 72 and 96 h LC50 of atrazine, calculated by probit analysis, were determined to be 77.091, 64.053, 49.100, 44.412 and 42.381 mg·L-1, respectively, in a semi static system with significant difference (p < 0.05 in LC10-90 values obtained for different times of exposure. In addition to concentration and time dependent decrease in mortality rate, stress signs in the form of behavioral changes were also observed in response to the test chemical. In fish exposed for 15 days to different sublethal concentrations of the herbicide (1/4 LC50 = ~10.600 mg·L-1, 1/8 LC50 = ~5.300 mg·L-1 and 1/10 LC50 = ~4.238 mg·L-1 induction of oxidative stress in the liver was evidence by increased lipid peroxidation levels. The antioxidants superoxide dismutase (SOD, catalase (CAT and glutathione reductase (GR responded positively in a concentration dependent pattern, thus, suggesting the use of these antioxidants as potential biomarkers of toxicity associated with contaminations exposure in freshwater fishes.

  15. Sublethal Photothermal Stimulation with a Micropulse Laser Induces Heat Shock Protein Expression in ARPE-19 Cells

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    Keiji Inagaki

    2015-01-01

    Full Text Available Purpose/Aim of the Study. Subthreshold micropulse diode laser photocoagulation is an effective treatment for macular edema. The molecular mechanisms underlying treatment success are poorly understood. Therefore, we investigated the effects of sublethal laser energy doses on a single layer of densely cultured ARPE-19 cells as a model of the human retinal pigment epithelium (RPE. Materials and Methods. A single layer of densely cultured human ARPE-19 cells was perpendicularly irradiated with a micropulse diode laser. Nonirradiated cells served as controls. Sublethal laser energy was applied to form a photocoagulation-like area in the cultured cell layers. Hsp70 expression was evaluated using quantitative polymerase chain reaction and immunocytochemistry. Results. Photocoagulation-like areas were successfully created in cultured ARPE-19 cell layers using sublethal laser energy with our laser irradiation system. Hsp70 mRNA expression in cell layers was induced within 30 min of laser irradiation, peaking at 3 h after irradiation. This increase was dependent on the number of laser pulses. Hsp70 upregulation was not observed in untreated cell layers. Immunostaining indicated that Hsp70 expression occurred concentrically around laser irradiation sites and persisted for 24 h following irradiation. Conclusion. Sublethal photothermal stimulation with a micropulse laser may facilitate Hsp70 expression in the RPE without inducing cellular damage.

  16. [Toxicity effects of phthalate substitute plasticizers used in toys].

    Science.gov (United States)

    Hirata-Koizumi, Mutsuko; Takahashi, Mika; Matsumoto, Mariko; Kawamura, Tomoko; Ono, Atsushi; Hirose, Akihiko

    2012-01-01

    Phthalate esters are widely used as plasticizers in polyvinyl chloride products. Because of human health concerns, regulatory authorities in Japan, US, Europe and other countries control the use of di(2-ethylhexyl) phthalate, diisononyl phthalate, di-n-butyl phthalate, butylbenzyl phthalate, diisodecyl phthalate and di-n-octyl phthalate for the toys that can be put directly in infants' mouths. While these regulatory actions will likely reduce the usage of phthalate esters, there is concern that other plasticizers that have not been sufficiently evaluated for safety will be used more frequently. We therefore collected and evaluated the toxicological information on di(2-ethylhexyl) terephthalate (DEHT), 1,2-cyclohexanedicarboxylic acid, diisononyl ester (DINCH), diisononyl adipate (DINA), 2,2,4-trimetyl-1,3-pentanediol diisobutyrate (TXIB), tri-n-butyl citrate (TBC) and acetyl tri-n-butyl citrate (ATBC) which were detected at a relatively high frequency in toys. The collected data have shown that chronic exposure to DEHT affects the eye and nasal turbinate, and DINCH exerts effects on the thyroid and kidney in rats. DINA and TXIB have been reported to have hepatic and renal effects in dogs or rats, and ATBC slightly affected the liver in rats. The NOAELs for repeated dose toxicity are relatively low for DINCH (40 mg/kg bw/day) and TXIB (30 mg/kg bw/day) compared with DEHT, DINA and ATBC. DEHT, TXIB and ATBC have been reported to have reproductive/developmental effects at relatively high doses in rats. For DINA and TBC, available data are insufficient for assessing the hazards, and therefore, adequate toxicity studies should be conducted. In the present review, the toxicity information on 6 alternatives to phthalate plasticizers is summarized, focusing on the effects after oral exposure, which is the route of most concern.

  17. Effects of sub-lethal concentrations of thyme and oregano essential oils, carvacrol, thymol, citral and trans-2-hexenal on membrane fatty acid composition and volatile molecule profile of Listeria monocytogenes, Escherichia coli and Salmonella enteritidis.

    Science.gov (United States)

    Siroli, Lorenzo; Patrignani, Francesca; Gardini, Fausto; Lanciotti, Rosalba

    2015-09-01

    The aim of this work was to investigate the modifications of cell membrane fatty acid composition and volatile molecule profiles of Listeria monocytogenes, Salmonella enteritidis, Escherichia coli, during growth in the presence of different sub-lethal concentrations of thyme and oregano essential oils as well as carvacrol, thymol, trans-2-hexenal and citral. The results evidenced that the tested molecules induced noticeable modifications of membrane fatty acid profiles and volatile compounds produced during the growth. Although specific differences in relation to the species considered were identified, the tested compounds induced a marked increase of some membrane associated fatty acids, particularly unsaturated fatty acids, trans-isomers, and specific released free fatty acids. These findings can contribute to the comprehension of the stress response mechanisms used by different pathogenic microorganisms often involved in food-borne diseases in relation to the exposure to sub-lethal concentrations of natural antimicrobials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Sublethal effect of concentrations of Metarhizium anisopliae (metsch. sorok on the larval stage and immunologic characteristics of Diatraea flavipennella (box (lepidoptera: crambidae

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    JENNIFER GUIMARÃES

    2014-12-01

    Full Text Available This work aimed to evaluate the effects of Metarhizium anisopliae on Diatraea flavipennella and investigate their immune response. Was observed the effect of M. anisopliae against larvae of D. flavipennella sprayed at concentrations of 103, 104, 105 conidia / mL, in which showed differences relative the larval period, extending up to 72.0 days in treatment and 25.0 days in the control. The results for hemocytes revealed that the most frequent cells when sprayed at the concentrations of 103, 105, 107 conidia / mL were the prohemocytes, spherulocytes, plasmatocytes and granulocytes in relation to adipohemocytes and oenocytoids. The level of nitric oxide was different between the control and the concentration 107 spores / mL (24, while the activity of phenoloxidase was similar among treatments in 24 and higher concentration 107 spores / mL (60h. In biochemical profile of hemocytes was a change in carbohydrates, lipids and proteins in response to the fungus. The results indicate that the fungus M. anisopliae can be used in the Integrated Management of D. flavipennella by presenting pathogenicity and interfere with their development even when exposed to small concentrations.

  19. Relationship between Sublethal Injury and Inactivation of Yeast Cells by the Combination of Sorbic Acid and Pulsed Electric Fields▿

    Science.gov (United States)

    Somolinos, M.; García, D.; Condón, S.; Mañas, P.; Pagán, R.

    2007-01-01

    The objective of this study was to investigate the occurrence of sublethal injury after the pulsed-electric-field (PEF) treatment of two yeasts, Dekkera bruxellensis and Saccharomyces cerevisiae, as well as the relation of sublethal injury to the inactivating effect of the combination of PEF and sorbic acid. PEF caused sublethal injury in both yeasts: more than 90% of surviving D. bruxellensis cells and 99% of surviving S. cerevisiae cells were sublethally injured after 50 pulses at 12 kV/cm in buffer at pHs of both 7.0 and 4.0. The proportion of sublethally injured cells reached a maximum after 50 pulses at 12.0 kV/cm (S. cerevisiae) or 16.5 kV/cm (D. bruxellensis), and it kept constant or progressively decreased at greater electric field strengths and with longer PEF treatments. Sublethally PEF-injured cells showed sensitivity to the presence of sorbic acid at a concentration of 2,000 ppm. A synergistic inactivating effect of the combination of PEF and sorbic acid was observed. Survivors of the PEF treatment were progressively inactivated in the presence of 2,000 ppm of sorbic acid at pH 3.8, with the combined treatments achieving more than log10 5 cycles of dead cells under the conditions investigated. This study has demonstrated the occurrence of sublethal injury after exposure to PEF, so yeast inactivation by PEF is not an all-or-nothing event. The combination of PEF and sorbic acid has proven to be an effective method to achieve a higher level of yeast inactivation. This work contributes to the knowledge of the mechanism of microbial inactivation by PEF, and it may be useful for improving food preservation by PEF technology. PMID:17468278

  20. Relationship between sublethal injury and inactivation of yeast cells by the combination of sorbic acid and pulsed electric fields.

    Science.gov (United States)

    Somolinos, M; García, D; Condón, S; Mañas, P; Pagán, R

    2007-06-01

    The objective of this study was to investigate the occurrence of sublethal injury after the pulsed-electric-field (PEF) treatment of two yeasts, Dekkera bruxellensis and Saccharomyces cerevisiae, as well as the relation of sublethal injury to the inactivating effect of the combination of PEF and sorbic acid. PEF caused sublethal injury in both yeasts: more than 90% of surviving D. bruxellensis cells and 99% of surviving S. cerevisiae cells were sublethally injured after 50 pulses at 12 kV/cm in buffer at pHs of both 7.0 and 4.0. The proportion of sublethally injured cells reached a maximum after 50 pulses at 12.0 kV/cm (S. cerevisiae) or 16.5 kV/cm (D. bruxellensis), and it kept constant or progressively decreased at greater electric field strengths and with longer PEF treatments. Sublethally PEF-injured cells showed sensitivity to the presence of sorbic acid at a concentration of 2,000 ppm. A synergistic inactivating effect of the combination of PEF and sorbic acid was observed. Survivors of the PEF treatment were progressively inactivated in the presence of 2,000 ppm of sorbic acid at pH 3.8, with the combined treatments achieving more than log10 5 cycles of dead cells under the conditions investigated. This study has demonstrated the occurrence of sublethal injury after exposure to PEF, so yeast inactivation by PEF is not an all-or-nothing event. The combination of PEF and sorbic acid has proven to be an effective method to achieve a higher level of yeast inactivation. This work contributes to the knowledge of the mechanism of microbial inactivation by PEF, and it may be useful for improving food preservation by PEF technology.

  1. Sublethal Effects of vATPase-A and Snf7 dsRNAs on Biology of Southern Corn Rootworm, Diabrotica undecimpunctata howardi Barber.

    Science.gov (United States)

    Pereira, Adriano E; Vélez, Ana M; Meinke, Lance J; Siegfried, Blair D

    2017-10-16

    RNA interference is a powerful tool against corn rootworm. Adults and neonates of southern corn rootworm, Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae), were exposed to the LC50 of vATPase-A and Snf7 double-stranded RNAs (dsRNAs), and the effects on female fecundity, egg viability, male fitness as measured by sperm viability and mating capacity, larval recovery along with dry weight, and instar determination 10 d after exposure to dsRNA, were determined. Significant reductions were observed for a number of parameters in dsRNA-exposed rootworms relative to control treatments. Female fecundity and larval recovery were significantly reduced after exposure to both dsRNAs. In addition, larval dry weight and recovery of 2nd and 3rd instars along with dry weight for 3rd instars were significantly reduced after neonate exposure to vATPase-A dsRNA. Neither dsRNA affected male capacity to mate or sperm viability after exposure to the respective LC50s. After 10 d of feeding on untreated corn roots, neonates that survived exposure for 2 d to the vATPase-A dsRNA LC50 exhibited lower dry weight than the control. There was significant gene knockdown in adult males and females after exposure for 5 d to LC50 of vATPase-A and Snf7 dsRNAs. The parameters are discussed in terms of fitness and possible outcomes after deployment of corn hybrids expressing dsRNAs. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Effect of sorption kinetics on nickel toxicity in methanogenic granular sludge

    NARCIS (Netherlands)

    Bartacek, J.; Fermoso, F.G.; Catena, A.B.; Lens, P.N.L.

    2010-01-01

    This study investigates the effect of nickel speciation and its equilibrium kinetics on the nickel toxicity to methylotrophic methanogenic activity. Toxicity tests were done with anaerobic granular sludge in three different media containing variable concentrations of complexing ligands. A

  3. Cytoprotective effects of dietary flavonoids against cadmium-induced toxicity.

    Science.gov (United States)

    Li, Xia; Jiang, Xinwei; Sun, Jianxia; Zhu, Cuijuan; Li, Xiaoling; Tian, Lingmin; Liu, Liu; Bai, Weibin

    2017-06-01

    Cadmium (Cd) damages the liver, kidney, bones, reproductive system, and other organs. Flavonoids, such as anthocyanins and flavonols, which are commonly found in plant foods, have shown protective effects against Cd-induced damage. The cytoprotective effects of flavonoids against Cd-induced diseases are mainly attributable to three mechanisms. First, flavonoids clear reactive oxygen species, thereby reducing lipid peroxide production and improving the activity of antioxidation enzymes. Second, flavonoids chelate Cd, thus reducing the accumulation of Cd and altering the levels of other essential metal ions in vivo. Third, flavonoids reduce DNA damage and inhibit apoptosis. In addition, flavonoids were found to inhibit inflammation and fibrosis and improve glycometabolism and the secretion of reproductive hormones. We introduce the daily dosage and absorption rate of flavonoids and then focus on their bioactive effects against Cd-induced toxicity and reveal the underlying metabolic pathway, which provides a basis for further study of the nutritional prevention of Cd-induced injury. In particular, a better understanding is needed of the structure-activity relationship of flavonoids against Cd toxicity, which has not yet been reported. © 2017 New York Academy of Sciences.

  4. Toxicity Effect of Silver Nanoparticles in Brine Shrimp Artemia

    Directory of Open Access Journals (Sweden)

    Chinnasamy Arulvasu

    2014-01-01

    Full Text Available The present study revealed the toxic effect of silver nanoparticles (AgNPs in Artemia nauplii and evaluated the mortality rate, hatching percentage, and genotoxic effect in Artemia nauplii/cysts. The AgNPs were commercially purchased and characterized using field emission scanning electron microscope with energy dispersive X-ray spectroscopy. Nanoparticles were spherical in nature and with size range of 30–40 nm. Artemia cysts were collected from salt pan, processed, and hatched in sea water. Artemia nauplii (II instar were treated using silver nanoparticles of various nanomolar concentrations and LC50 value (10 nM and mortality rate (24 and 48 hours was evaluated. Hatching percentage of decapsulated cysts treated with AgNPs was examined. Aggregation of AgNPs in the gut region of nauplii was studied using phase contrast microscope and apoptotic cells in nauplii stained with acridine orange were observed using fluorescence microscope. DNA damage of single cell of nauplii was determined by comet assay. This study showed that as the concentration of AgNPs increased, the mortality rate, aggregation in gut region, apoptotic cells, and DNA damage increased in nauplii, whereas the percentage of hatching in Artemia cysts decreased. Thus this study revealed that the nanomolar concentrations of AgNPs have toxic effect on both Artemia nauplii and cysts.

  5. Toxicity effect of silver nanoparticles in brine shrimp Artemia.

    Science.gov (United States)

    Arulvasu, Chinnasamy; Jennifer, Samou Michael; Prabhu, Durai; Chandhirasekar, Devakumar

    2014-01-01

    The present study revealed the toxic effect of silver nanoparticles (AgNPs) in Artemia nauplii and evaluated the mortality rate, hatching percentage, and genotoxic effect in Artemia nauplii/cysts. The AgNPs were commercially purchased and characterized using field emission scanning electron microscope with energy dispersive X-ray spectroscopy. Nanoparticles were spherical in nature and with size range of 30-40 nm. Artemia cysts were collected from salt pan, processed, and hatched in sea water. Artemia nauplii (II instar) were treated using silver nanoparticles of various nanomolar concentrations and LC50 value (10 nM) and mortality rate (24 and 48 hours) was evaluated. Hatching percentage of decapsulated cysts treated with AgNPs was examined. Aggregation of AgNPs in the gut region of nauplii was studied using phase contrast microscope and apoptotic cells in nauplii stained with acridine orange were observed using fluorescence microscope. DNA damage of single cell of nauplii was determined by comet assay. This study showed that as the concentration of AgNPs increased, the mortality rate, aggregation in gut region, apoptotic cells, and DNA damage increased in nauplii, whereas the percentage of hatching in Artemia cysts decreased. Thus this study revealed that the nanomolar concentrations of AgNPs have toxic effect on both Artemia nauplii and cysts.

  6. Effect of trifluoperazine on toxicity, HIF-1α induction and hepatocyte regeneration in acetaminophen toxicity in mice

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, Shubhra, E-mail: SCHAUDHURI@uams.edu [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); McCullough, Sandra S., E-mail: mcculloughsandras@uams.edu [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); Hennings, Leah, E-mail: lhennings@uams.edu [Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); Brown, Aliza T., E-mail: brownalizat@uams.edu [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); Li, Shun-Hwa [Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI (United States); Simpson, Pippa M., E-mail: psimpson@mcw.edu [Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI (United States); Hinson, Jack A., E-mail: hinsonjacka@uams.edu [Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); James, Laura P., E-mail: jameslaurap@uams.edu [Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States); Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, Arkansas Children' s Hospital Research Institute, Little Rock, AR (United States)

    2012-10-15

    Oxidative stress and mitochondrial permeability transition (MPT) are important mechanisms in acetaminophen (APAP) toxicity. The MPT inhibitor trifluoperazine (TFP) reduced MPT, oxidative stress, and toxicity in freshly isolated hepatocytes treated with APAP. Since hypoxia inducible factor-one alpha (HIF-1α) is induced very early in APAP toxicity, a role for oxidative stress in the induction has been postulated. In the present study, the effect of TFP on toxicity and HIF-1α induction in B6C3F1 male mice treated with APAP was examined. Mice received TFP (10 mg/kg, oral gavage) prior to APAP (200 mg/kg IP) and at 7 and 36 h after APAP. Measures of metabolism (hepatic glutathione and APAP protein adducts) were comparable in the two groups of mice. Toxicity was decreased in the APAP/TFP mice at 2, 4, and 8 h, compared to the APAP mice. At 24 and 48 h, there were no significant differences in toxicity between the two groups. TFP lowered HIF-1α induction but also reduced the expression of proliferating cell nuclear antigen, a marker of hepatocyte regeneration. TFP can also inhibit phospholipase A{sub 2}, and cytosolic and secretory PLA{sub 2} activity levels were reduced in the APAP/TFP mice compared to the APAP mice. TFP also lowered prostaglandin E{sub 2} expression, a known mechanism of cytoprotection. In summary, the MPT inhibitor TFP delayed the onset of toxicity and lowered HIF-1α induction in APAP treated mice. TFP also reduced PGE{sub 2} expression and hepatocyte regeneration, likely through a mechanism involving PLA{sub 2}. -- Highlights: ► Trifluoperazine reduced acetaminophen toxicity and lowered HIF-1α induction. ► Trifluoperazine had no effect on the metabolism of acetaminophen. ► Trifluoperazine reduced hepatocyte regeneration. ► Trifluoperazine reduced phospholipase A{sub 2} activity and prostaglandin E{sub 2} levels.

  7. Behavioral effects of ketamine and toxic interactions with psychostimulants

    Directory of Open Access Journals (Sweden)

    Yamamoto Keiichi

    2006-03-01

    Full Text Available Abstract Background The anesthetic drug ketamine (KT has been reported to be an abused drug and fatal cases have been observed in polydrug users. In the present study, considering the possibility of KT-enhanced toxic effects of other drugs, and KT-induced promotion of an overdose without making the subject aware of the danger due to the attenuation of several painful subjective symptoms, the intraperitoneal (i.p. KT-induced alterations in behaviors and toxic interactions with popular co-abused drugs, the psychostimulants cocaine (COC and methamphetamine (MA, were examined in ICR mice. Results A single dose of KT caused hyperlocomotion in a low (30 mg/kg, i.p. dose group, and hypolocomotion followed by hyperlocomotion in a high (100 mg/kg, i.p. dose group. However, no behavioral alterations derived from enhanced stress-related depression or anxiety were observed in the forced swimming or the elevated plus-maze test. A single non-fatal dose of COC (30 mg/kg, i.p. or MA (4 mg/kg, i.p. caused hyperlocomotion, stress-related depression in swimming behaviors in the forced swimming test, and anxiety-related behavioral changes (preference for closed arms in the elevated plus-maze test. For the COC (30 mg/kg or MA (4 mg/kg groups of mice simultaneously co-treated with KT, the psychostimulant-induced hyperlocomotion was suppressed by the high dose KT, and the psychostimulant-induced behavioral alterations in the above tests were reversed by both low and high doses of KT. For the toxic dose COC (70 mg/kg, i.p.- or MA (15 mg/kg, i.p.-only group, mortality and severe seizures were observed in some animals. In the toxic dose psychostimulant-KT groups, KT attenuated the severity of seizures dose-dependently. Nevertheless, the mortality rate was significantly increased by co-treatment with the high dose KT. Conclusion Our results demonstrated that, in spite of the absence of stress-related depressive and anxiety-related behavioral alterations following a single

  8. STUDY OF THE TOXIC EFFECTS OF CYPERMETHRIN IN EXPERIMENTAL ANIMALS

    Directory of Open Access Journals (Sweden)

    Syed Mehmood Hasan

    2016-06-01

    Full Text Available This study focuses on the toxic effects of a commercially available pesticide, cypermethrin (CM, on animals. This pesticide was administered in the form of aerosol spray through a nebulizer. The study was performed in four different groups and a constant dose of the pesticide was administered once, twice, thrice and four times a day to the respective group for a period of 30 days. The animals were then dissected to study the pesticide effects on different organs. The organs were preserved in 10% formalin. The tissues were processed by basic histopathological method and the slides were prepared for observation. The results were recorded on a performa and were quantified by a unique scoring system. It is concluded that the injurious effects to the mentioned organs were dose and frequency dependent.

  9. Contaminated marine sediments: Water column and interstitial toxic effects

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, R.M.; Schweitzer, K.A.; McKinney, R.A.; Phelps, D.K.

    1993-01-01

    The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentrations of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial waters did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

  10. Contaminated marine sediments: Water column and interstitial toxic effects

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, R.M.; McKinney, R.A. (Science Applications International Corp., Narragansett, RI (United States)); Schweitzer, K.A. (Chemical Waste Management, Inc., Dartmouth, MA (United States)); Phelps, D.K. (Environmental Protection Agency, Narragansett, RI (United States))

    1993-01-01

    The toxicity that contaminated sediments may introduce into the water column has not been measured extensively. In order to quantify this potential toxicity, the seawater overlying two uncontaminated and three contaminated marine sediments was evaluated in the laboratory with the sea urchin Arbacia punctulata fertilization test. Concentration of polychlorinated biphenyls (PCBs) and copper, as representative contaminants, were also measured. To characterize sources of toxicity, samples were chemically manipulated using reversed-phase chromatography, cation exchange, and chelation. Water column toxicity and contaminant concentrations were higher in the suspended exposures than in bedded exposures. Interstitial water toxicity and contaminant concentrations were generally greater than either bedded or suspended exposures. Chemical manipulation indicated that the observed toxicity in water column exposures was probably caused by metallic and/or nonionic organic contaminants. Conversely, manipulation of interstitial water did not result in significantly reduced toxicity, suggesting that other toxicants such as ammonia and hydrogen sulfide may be active.

  11. Larval Red Drum (Sciaenops ocellatus) Sublethal Exposure to Weathered Deepwater Horizon Crude Oil: Developmental and Transcriptomic Consequences.

    Science.gov (United States)

    Xu, Elvis Genbo; Khursigara, Alex J; Magnuson, Jason; Hazard, E Starr; Hardiman, Gary; Esbaugh, Andrew J; Roberts, Aaron P; Schlenk, Daniel

    2017-09-05

    The Deepwater Horizon (DWH) incident resulted in extensive oiling of the pelagic zone and shoreline habitats of many commercially important fish species. Exposure to the water-accommodated fraction (WAF) of oil from the spill causes developmental toxicity through cardiac defects in pelagic fish species. However, few studies have evaluated the effects of the oil on near-shore estuarine fish species such as red drum (Sciaenops ocellatus). Following exposure to a certified weathered slick oil (4.74 μg/L ∑PAH50) from the DWH event, significant sublethal impacts were observed ranging from impaired nervous system development [average 17 and 22% reductions in brain and eye area at 48 h postfertilization (hpf), respectively] to abnormal cardiac morphology (100% incidence at 24, 48, and 72 hpf) in red drum larvae. Consistent with the phenotypic responses, significantly differentially expressed transcripts, enriched gene ontology, and altered functions and canonical pathways predicted adverse outcomes in nervous and cardiovascular systems, with more pronounced changes at later larval stages. Our study demonstrated that the WAF of weathered slick oil of DWH caused morphological abnormalities predicted by a suite of advanced bioinformatic tools in early developing red drum and also provided the basis for a better understanding of molecular mechanisms of crude oil toxicity in fish.

  12. Influence of biorhythms on sensitivity of Nerita to pollutants at Sublethal levels

    Energy Technology Data Exchange (ETDEWEB)

    Battershill, C.N.; Bergquist, P.R.

    1984-01-01

    Intrinsic rhythmic activity of Nerita (Melanerita) atramentosa melanotragus was assessed under constant laboratory conditions. Activity proved to be a sensitive indicator of toxicity, and was affected by low levels of a relatively new oil dispersing agent, Shell SD LTX. How the state of activity influenced animal sensitivity to Shell SD LTX and to an oil, Maui Condensate, was investigated using short-term recovery experiments. Nerita were most sensitive during their active phase, and results during this period differed significantly from tests carried out during the inactive phase of the animal. Dispersant/oil mixture proved to be highly toxic. These findings have ecological implications and permit comment relating to the design of sublethal toxicity tests. These subjects are discussed. 37 references, 3 figures, 2 tables.

  13. Aloe vera: A review of toxicity and adverse clinical effects.

    Science.gov (United States)

    Guo, Xiaoqing; Mei, Nan

    2016-04-02

    The Aloe plant is employed as a dietary supplement in a variety of foods and as an ingredient in cosmetic products. The widespread human exposure and its potential toxic and carcinogenic activities raise safety concerns. Chemical analysis reveals that the Aloe plant contains various polysaccharides and phenolic chemicals, notably anthraquinones. Ingestion of Aloe preparations is associated with diarrhea, hypokalemia, pseudomelanosis coli, kidney failure, as well as phototoxicity and hypersensitive reactions. Recently, Aloe vera whole leaf extract showed clear evidence of carcinogenic activity in rats, and was classified by the International Agency for Research on Cancer as a possible human carcinogen (Group 2B). This review presents updated information on the toxicological effects, including the cytotoxicity, genotoxicity, carcinogenicity, and adverse clinical effects of Aloe vera whole leaf extract, gel, and latex.

  14. Critical evaluation of toxic versus beneficial effects of methylglyoxal.

    Science.gov (United States)

    Talukdar, D; Chaudhuri, B S; Ray, M; Ray, S

    2009-10-01

    In various organisms, an array of enzymes is involved in the synthesis and breakdown of methylglyoxal. Through these enzymes, it is intimately linked to several other physiologically important metabolites, suggesting that methylglyoxal has some important role to play in the host organism. Several in vitro and in vivo studies showed that methylglyoxal acts specifically against different types of malignant cells. These studies culminated in a recent investigation to evaluate a methylglyoxal-based formulation in treating a small group of cancer patients, and the results were promising. Methylglyoxal acts against a number of pathogenic microorganisms. However, recent literature abounds with the toxic effects of methylglyoxal, which are supposed to be mediated through methylglyoxal-derived advanced glycation end products (AGE). Many diseases such as diabetes, cataract formation, hypertension, and uremia are proposed to be intimately linked with methylglyoxal-derived AGE. However methylglyoxal-derived AGE formation and subsequent pathogenesis might be a very minor event because AGE are nonspecific reaction products that are derived through the reactions of carbonyl groups of reducing sugars with amino groups present in the side chains of lysine and arginine and in terminal amino groups of proteins. Moreover, the results of some in vitro experiments with methylglyoxal under non-physiological conditions were extrapolated to the in vivo situation. Some experiments even showed contradictory results and were differently interpreted. For this reason conclusions about the potential beneficial effects of methylglyoxal have often been neglected, thus hindering the advancement of medical science and causing some confusion in fundamental understanding. Overall, the potential beneficial effects of methylglyoxal far outweigh its possible toxic role in vivo, and it should be utilized for the benefit of suffering humanity.

  15. Teratogenic and toxic effects of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.:Fr.) P. Karst. (higher Basidiomycetes), on zebrafish embryo as model.

    Science.gov (United States)

    Dulay, Rich Milton R; Kalaw, Sofronio P; Reyes, Renato G; Alfonso, Noel F; Eguchi, Fumio

    2012-01-01

    This paper highlights the teratogenic and toxic effects of Ganoderma lucidum (Lingzhi or Reishi mushroom) extract on zebrafish embryos. Hatchability, malformations, and lethality rate of zebrafish embryos were assessed to provide valuable information regarding the potential teratogenic activity of G. lucidum. Hatching was completed 48 h post treatment application (hpta) at 1% or lower concentrations of extract and embryo water. The hatching rate of embryos treated with 5% or higher concentrations was significantly lower (p> 0.05) than the control. Tail malformation was the most marked morphological abnormality in embryos at 72 hpta, which was obviously caused by 1% extract (55.56% tail malformation) and was observed in all embryos exposed to 5% of extract. Growth retardation was evident in embryos exposed to 5%, 10%, and 20%. However, lethal effect of extract of G. lucidum was dependent on dose and time of exposure. Mortality rates of embryos treated with 5% (44.44%) or higher concentrations of the extract was significantly higher (p > 0.05) than that of the control embryos at 72 hpta. These results suggest that G. lucidum extract has lethal and sub-lethal effects on zebrafish embryos.

  16. Lethal and sub-lethal evaluation of Indigo Carmine dye and byproducts after TiO2 photocatalysis in the immune system of Eisenia andrei earthworms.

    Science.gov (United States)

    Genázio Pereira, Patrícia Christina; Reimão, Roberta Valoura; Pavesi, Thelma; Saggioro, Enrico Mendes; Moreira, Josino Costa; Veríssimo Correia, Fábio

    2017-09-01

    The Indigo carmine (IC) dye has been widely used in textile industries, even though it has been considered toxic for rats, pigs and humans. Owing to its toxicity, wastes containing this compound should be treated to minimize or eliminate their toxic effects on the biota. As an alternative to wastewater treatment, advanced oxidative processes (AOPs) have been highlighted due to their high capacity to destruct organic molecules. In this context, this study aimed to evaluate Indigo Carmine toxicity to soil organisms using the earthworm Eisenia andrei as a model-organism and also verify the efficiency of AOP in reducing its toxicity to these organisms. To this end, lethal (mortality) and sub-lethal (loss or gain of biomass, reproduction, behavior, morphological changes and immune system cells) effects caused by this substance and its degradation products in these annelids were evaluated. Morphological changes were observed even in organisms exposed to low concentrations, while mortality was the major effect observed in individuals exposed to high levels of indigo carmine dye. The organisms exposed to the IC during the contact test showed mortality after 72h of exposure (LC50 = 75.79mgcm-2), while those exposed to photoproducts showed mortality after 48h (LC50 = 243min). In the chronic study, the organisms displayed a mortality rate of 14%, while those exposed to the photoproduct reached up to 32.7%. A negative influence of the dye on the reproduction rate was observed, while by-products affected juvenile survival. A loss of viability and alterations in the cellular proportion was verified during the chronic test. However, the compounds did not alter the behavior of the annelids in the leak test (RL ranged from 20% to 30%). Although photocatalysis has been presented as an alternative technology for the treatment of waste containing the indigo carmine dye, this process produced byproducts even more toxic than the original compounds to E. andrei. Copyright © 2017

  17. Pyrethroid toxicity in silver catfish, Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Francisco P. Montanha

    2012-12-01

    Full Text Available This study aimed to determine both the lethal and sublethal concentrations of Cypermethrin in young Silver Catfish (Brazilian "Jundiá", Rhamdia quelen on aquatic environment during 96 hours, as well as to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development period of Rhamdia quelen, and to verify their respective rates of fertilization, hatching and survival. Pyrethroid nowadays is a widely used insecticide, which presents a high toxicity to fish. In order to determine lethal and sublethal concentrations, 120 silver catfish were used; each one had an average weight of 59.58±4.50g and an average size of 20.33±2.34cm. Concentrations used were 0, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0 and 20.0mg of Cypermethrin per liter of water (mg/L. Fish were exposed to the product in 30-liter fish tanks. In each fish tank there were four fishes and the product was applied three times, i.e., a total of twelve fish were exposed to the product at each application, and a total of 120 fish during the entire experiment (n=120. In order to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development, ovulation induction was performed on female fishes using hormones, and then and egg collection was performed. The eggs were then hydrated and fertilized in Cypermethrin and Deltamethrin in different concentrations: 0.001, 0.01, 0.1, 1.0 and 10.0mg/L of Cypermethrin and 0.001, 0.01, 0.1, 0.5 and 1.0mg/L of Deltamethrin, in addition to the control group (0mg/L. After fertilization, the eggs were kept in containers with the respective pesticides of Cypermethrin and Deltamethrin until hatching, when hatching rate was verified. Then the alevins, from the hatching, were kept on their respective concentrations of Cypermethrin and Deltamethrin so that the survival rate could be analyzed regarding the tested insecticides, during both 12-hour and 24-hour periods

  18. Can’t take the heat: Temperature-enhanced toxicity in the mayfly Isonychia bicolor exposed to the neonicotinoid insecticide imidacloprid

    Energy Technology Data Exchange (ETDEWEB)

    Camp, A.A., E-mail: aacamp@ncsu.edu; Buchwalter, D.B., E-mail: dbbuchwa@ncsu.edu

    2016-09-15

    Highlights: • Temperature has a strong modulating influence on toxicity in aquatic insects. • Increasing temperature decreased the time to onset of imidacloprid toxicity. • Increasing temperature increased the uptake rates of imidacloprid in different taxa. • Sublethal behavioral effects of contaminants are important to assess in toxicology. - Abstract: Neonicotinoid insecticide usage has increased globally in recent decades. Neonicotinoids, such as imidacloprid, are potent insect neurotoxicants that may pose a threat to non-target aquatic organisms, such as aquatic insects. In nature, insects typically live in thermally fluctuating conditions, which may significantly alter both contaminant exposures and affects. Here we investigate the relationship between temperature and time-to-effect for imidacloprid toxicity with the aquatic insect Isonychia bicolor, a lotic mayfly. Additionally, we examined the mechanisms driving temperature-enhanced toxicity including metabolic rate, imidacloprid uptake rate, and tissue bioconcentration. Experiments included acute toxicity tests utilizing sublethal endpoints and mortality, as well as respirometry and radiotracer assays with [{sup 14}C] imidacloprid. Further, we conducted additional uptake experiments with a suite of aquatic invertebrates (including I. bicolor, Neocloeon triangulifer, Macaffertium modestum, Pteronarcys proteus, Acroneuria carolinensis, and Pleuroceridae sp) to confirm and contextualize our findings from initial experiments. The 96 h EC{sub 50} (immobility) for I. bicolor at 15 °C was 5.81 μg/L which was approximately 3.2 fold lower than concentrations associated with 50% mortality. Assays examining the impact of temperature were conducted at 15, 18, 21, and 24 °C and demonstrated that time-to-effect for sublethal impairment and immobility was significantly decreased with increasing temperature. Uptake experiments with [{sup 14}C] imidacloprid revealed that initial uptake rates were significantly

  19. Toxicity of silica nanoparticles and the effect of protein corona

    DEFF Research Database (Denmark)

    Foldbjerg, Rasmus; Jespersen, Lars Vesterby; Wang, Jing

    2010-01-01

      The cytotoxicity of silica nanoparticles (NPs) was investigated in the human lung cell line, A549. Silica NPs of different sizes (DLS size; 16-42 nm) were used to determine appropriate dose metrics whereas the effect of the NP corona was tested by coating the NPs with bovine serum albumin (BSA...... upon silica NP exposure. The silica NP surface area was found to be the best dose metric for predicting cytotoxicity and IL-8 release. Generally, the NPs were only cytotoxic at high concentrations and BSA-coating of the NPs significantly decreased the cytotoxicity and cellular IL-8 secretion. All...... the NPs were found to cause increased cellular ROS production which could not be reduced by antioxidant treatment. In conclusion, our data suggest that surface area is an appropriate dose metric to predict cytotoxicity and inflammation induced by silica nanoparticles. Furthermore, the reduced toxicity...

  20. Toxic effects of skin-lightening products in Canadian immigrants.

    Science.gov (United States)

    Mistry, Nisha; Shapero, Jonathan; Kundu, Roopal V; Shapero, Harvey

    2011-01-01

    The cultural practice of skin bleaching is highly prevalent in Africa. Most reported cases of toxic effects of skin-lightening products occur in this region. To describe cases of misuse of over-the-counter (OTC) cosmetic skin-lightening products occurring in Canadian immigrants. Two cases of Canadian immigrants with severe complications from OTC skin-bleaching agents were identified in a community-based dermatology practice in Toronto. The case histories were reviewed and analyzed. A 28-year-old African-Canadian woman developed extensive striae from long-term use of a topical cream containing clobetasol that she had purchased in a Caribbean health food store. A 55-year-old African-Canadian woman developed exogenous ochronosis from the use of a topical bleaching agent she had purchased in Ghana. Cosmetic skin lightening with unregulated topical products occurs in Canada. Dermatologists working in Canada need to be aware of this practice to provide appropriate directive care.

  1. Effects of Heavy Metal Toxicity on Human Health

    OpenAIRE

    Guluzar Ozbolat; Abdullah Tuli

    2016-01-01

    Heavy metals are the elements that can be toxic even at low concentrations. It is often used as a group name for metals and semimetals (metalloids) that have been associated with contamination and potential toxicity or ecotoxicity. Heavy metals are toxic to human health. Because it cannot be discarded with (kidney, liver intestine, skin, lung) without special support from most of the body's normal excretion routes Therefore, a large part of the heavy metals accumulate in biological organisms...

  2. Sublethal consequences of urban life for wild vertebrates

    National Research Council Canada - National Science Library

    Gallagher, Austin J; Peiman, Kathryn S; de Bruijn, Robert; Cooke, Steven J; Birnie-Gauvin, Kim

    2016-01-01

    ... — while others have not. Here we present a review of the sublethal consequences of life in the city for wild vertebrates, and demonstrate that urban animals face an almost completely different set of physiological...

  3. Cytokines reduce toxic effects of ethanol on oligodendroglia.

    Science.gov (United States)

    Benjamins, Joyce A; Nedelkoska, Liljana; Lisak, Robert P; Hannigan, John H; Sokol, Robert J

    2011-09-01

    To characterize immunomodulatory mechanisms that affect oligodendroglia (OL) and white matter following ethanol exposure during early CNS development, we investigated the direct effects of ethanol and cytokines on glia. Mixed glial cultures from newborn rat brain were exposed to 6.5-130 mM ethanol for 1-3 days. OL were sensitive to ethanol, with death ranging from 32 to 88% with increasing time and ethanol concentrations. Little cell death occurred in astroglia or microglia. Mixtures of cytokines representative of those produced by pro-inflammatory Th1 and monocyte/macrophage (M/M) cells as well as those produced by anti-inflammatory Th2 cells were all protective. Three of the cytokines in the Th1 mixture, IL-2, TNF-α and IFN-γ, were protective individually, although no single cytokine was as effective as the mixture. The protective effects of the Th1 mixture and of IL-2 were reversed by inhibition of both MAP kinase and PI-3 kinase signaling pathways. We conclude that cytokines can act either directly on OL or indirectly through effects on astroglia or microglia to protect OL from ethanol toxicity.

  4. Impaired ecosystem process despite little effects on populations: modeling combined effects of warming and toxicants.

    Science.gov (United States)

    Galic, Nika; Grimm, Volker; Forbes, Valery E

    2017-08-01

    Freshwater ecosystems are exposed to many stressors, including toxic chemicals and global warming, which can impair, separately or in combination, important processes in organisms and hence higher levels of organization. Investigating combined effects of warming and toxicants has been a topic of little research, but neglecting their combined effects may seriously misguide management efforts. To explore how toxic chemicals and warming, alone and in combination, propagate across levels of biological organization, including a key ecosystem process, we developed an individual-based model (IBM) of a freshwater amphipod detritivore, Gammarus pseudolimnaeus, feeding on leaf litter. In this IBM, life history emerges from the individuals' energy budgets. We quantified, in different warming scenarios (+1-+4 °C), the effects of hypothetical toxicants on suborganismal processes, including feeding, somatic and maturity maintenance, growth, and reproduction. Warming reduced mean adult body sizes and population abundance and biomass, but only in the warmest scenarios. Leaf litter processing, a key contributor to ecosystem functioning and service delivery in streams, was consistently enhanced by warming, through strengthened interaction between the detritivorous consumer and its resource. Toxicant effects on feeding and maintenance resulted in initially small adverse effects on consumers, but ultimately led to population extinction and loss of ecosystem process. Warming in combination with toxicants had little effect at the individual and population levels, but ecosystem process was impaired in the warmer scenarios. Our results suggest that exposure to the same amount of toxicants can disproportionately compromise ecosystem processing depending on global warming scenarios; for example, reducing organismal feeding rates by 50% will reduce resource processing by 50% in current temperature conditions, but by up to 200% with warming of 4 °C. Our study has implications for

  5. Environmental levels of Zn do not protect embryos from Cu toxicity in three species of amphibians.

    Science.gov (United States)

    Weir, Scott M; Flynn, R Wesley; Scott, David E; Yu, Shuangying; Lance, Stacey L

    2016-07-01

    Contaminants often occur as mixtures in the environment, but investigations into toxicity usually employ a single chemical. Metal contaminant mixtures from anthropogenic activities such as mining and coal combustion energy are widespread, yet relatively little research has been performed on effects of these mixtures on amphibians. Considering that amphibians tend to be highly sensitive to copper (Cu) and that metal contaminants often occur as mixtures in the environment, it is important to understand the interactive effects that may result from multiple metals. Interactive effects of Cu and zinc (Zn) on amphibians have been reported as antagonistic and, conversely, synergistic. The goal of our study was to investigate the role of Zn in Cu toxicity to amphibians throughout the embryonic developmental period. We also considered maternal effects and population differences by collecting multiple egg masses from contaminated and reference areas for use in four experiments across three species. We performed acute toxicity experiments with Cu concentrations that cause toxicity (10-200 μg/L) in the absence of other contaminants combined with sublethal concentrations of Zn (100 and 1000 μg/L). Our results suggest very few effects of Zn on Cu toxicity at these concentrations of Zn. As has been previously reported, we found that maternal effects and population history had significant influence on Cu toxicity. The explanation for a lack of interaction between Cu and Zn in this experiment is unknown but may be due to the use of sublethal Zn concentrations when previous experiments have used Zn concentrations associated with acute toxicity. Understanding the inconsistency of amphibian Cu/Zn mixture toxicity studies is an important research direction in order to create generalities that can be used to understand risk of contaminant mixtures in the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Toxic effects of chromium on tannery workers at Sialkot (Pakistan).

    Science.gov (United States)

    Khan, Dilshad Ahmed; Mushtaq, Shahida; Khan, Farooq Ahmad; Khan, Muhammad Qaiser Alam

    2013-03-01

    Chromium is widely used in the leather industry, and tannery workers are under constant threat of adverse health effects due to its excessive exposure. Our objective was to find out the toxic effects of chromium on tannery workers at Sialkot, Pakistan. A total of 240 males consisting of 120 workers from tanneries at Sialkot and equal number of controls were included. Blood complete counts, high-sensitive C-reactive protein, malondialdehyde and routine biochemical tests were carried out by routine procedures. Chromium levels in blood (BCr) and urine were analyzed using graphite furnace atomic absorption spectrophotometer Perkin Elmer analyst-200. Results revealed that all the workers were male with average age of 33 years and 15 (13%) had skin rashes, 14 (12%) had chronic bronchitis, 10 (8%) had gastritis and 4 (3%) conjunctivitis. The tannery workers had significantly raised median (interquartile range) of BCr 569 (377-726) nmol/L as compared to 318 (245-397) nmol/L in the control (p tanneries at Sialkot. They had significantly raised chromium levels in their biological fluids and adverse health effects due to enhanced oxidative stress and inflammatory changes.

  7. Sublethal doses of imidacloprid disrupt sexual communication and host finding in a parasitoid wasp

    Science.gov (United States)

    Tappert, Lars; Pokorny, Tamara; Hofferberth, John; Ruther, Joachim

    2017-02-01

    Neonicotinoids are widely used insecticides, but their use is subject of debate because of their detrimental effects on pollinators. Little is known about the effect of neonicotinoids on other beneficial insects such as parasitoid wasps, which serve as natural enemies and are crucial for ecosystem functioning. Here we show that sublethal doses of the neonicotinoid imidacloprid impair sexual communication and host finding in the parasitoid wasp Nasonia vitripennis. Depending on the dose, treated females were less responsive to the male sex pheromone or unable to use it as a cue at all. Courtship behaviour of treated couples was also impeded resulting in a reduction of mating rates by up to 80%. Moreover, treated females were no longer able to locate hosts by using olfactory cues. Olfaction is crucial for the reproductive success of parasitoid wasps. Hence, sublethal doses of neonicotinoids might compromise the function of parasitoid wasps as natural enemies with potentially dire consequences for ecosystem services.

  8. Fate and toxic effects of environmental stressors: environmental control.

    Science.gov (United States)

    Zhuang, Jie; Yu, Han-Qing; Henry, Theodore B; Sayler, Gary S

    2015-12-01

    The potential for toxicants to harm organisms in the environment is influenced by the physicochemistry of the substances and their environmental behaviors and transformation within ecosystems. This special issue is composed of 20 papers that report on studies which have investigated the fate and toxicity of various toxicants including engineered nanoparticles, pharmaceuticals and personal care products, antibiotics, pathogens, heavy metals, and agricultural nutrients. The environmental transformations of these substances and how these processes affect their toxicity are emphasized. This paper highlights the important findings and perspectives of the selected papers in this special edition, with an aim of providing insights into full-scale evaluation on the toxicity of various contaminants that exist in ecosystems. General suggestions are provided for the future directions of toxicological research.

  9. Both genome and cytosol dynamics change in E. coli challenged with sublethal rifampicin

    Science.gov (United States)

    Wlodarski, Michal; Raciti, Bianca; Kotar, Jurij; Cosentino Lagomarsino, Marco; Fraser, Gillian M.; Cicuta, Pietro

    2017-02-01

    While the action of many antimicrobial drugs is well understood at the molecular level, a systems-level physiological response to antibiotics remains largely unexplored. This work considers fluctuation dynamics of both the chromosome and cytosol in Escherichia coli, and their response to sublethal treatments of a clinically important antibiotic, rifampicin. We precisely quantify the changes in dynamics of chromosomal loci and cytosolic aggregates (a rheovirus nonstructural protein known as μNS-GFP), measuring short time-scale displacements across several hours of drug exposure. To achieve this we develop an empirical method correcting for photo-bleaching and loci size effects. This procedure allows us to characterize the dynamic response to rifampicin in different growth conditions, including a customised microfluidic device. We find that sub-lethal doses of rifampicin cause a small but consistent increase in motility of both the chromosomal loci and cytosolic aggregates. Chromosomal and cytosolic responses are consistent with each other and between different growth conditions.

  10. Effect of low-purity Fenton reagents on toxicity of textile dyeing effluent to Daphnia magna.

    Science.gov (United States)

    Na, Joorim; Yoo, Jisu; Nam, Gwiwoong; Jung, Jinho

    2017-09-20

    This study aimed to identify the source of toxicity in textile dyeing effluent collected from February to July 2016, using Daphnia magna as a test organism. Toxicity identification evaluation (TIE) procedures were used to identify the toxicants in textile dyeing effluent, and Jar testing to simulate the Fenton process was conducted to identify the source of toxicants. Textile dyeing effluent was acutely toxic to D. magna [from 1.5 to 9.7 toxic units (TU)] during the study period. TIE results showed that Zn derived from the Fenton process was a key toxicant in textile dyeing effluent. Additionally, Jar testing revealed that low-purity Fenton reagents (FeCl2 and FeSO4), which contained large amounts of Zn (89 838 and 610 mg L-1, respectively), were the source of toxicity. Although we were unable to conclusively identify the residual toxicity (approx. 1.4 TU of 9.71 TU) attributable to unknown toxicants in textile dyeing effluent, the findings of this study suggest that careful operation of the Fenton treatment process could contribute to eliminating its unintended toxic effects on aquatic organisms.

  11. Effects of nanomaterial physicochemical properties on in vivo toxicity.

    Science.gov (United States)

    Aillon, Kristin L; Xie, Yumei; El-Gendy, Nashwa; Berkland, Cory J; Forrest, M Laird

    2009-06-21

    It is well recognized that physical and chemical properties of materials can alter dramatically at nanoscopic scale, and the growing use of nanotechnologies requires careful assessment of unexpected toxicities and biological interactions. However, most in vivo toxicity concerns focus primarily on pulmonary, oral, and dermal exposures to ultrafine particles. As nanomaterials expand as therapeutics and as diagnostic tools, parenteral administration of engineered nanomaterials should also be recognized as a critical aspect for toxicity consideration. Due to the complex nature of nanomaterials, conflicting studies have led to different views of their safety. Here, the physicochemical properties of four representative nanomaterials (dendrimers, carbon nanotubes, quantum dots, and gold nanoparticles) as it relates to their toxicity after systemic exposure is discussed.

  12. Toxic effects of the easily avoidable phthalates and parabens.

    Science.gov (United States)

    Crinnion, Walter J

    2010-09-01

    Some environmental toxins like DDT and other chlorinated compounds accumulate in the body because of their fat-soluble nature. Other compounds do not stay long in the body, but still cause toxic effects during the time they are present. For serious health problems to arise, exposure to these rapidly-clearing compounds must occur on a daily basis. Two such classes of compounds are the phthalate plasticizers and parabens, both of which are used in many personal care products, some medications, and even foods and food preservation. The phthalates are commonly found in foods and household dust. Even though they have relatively short half-lives in humans, phthalates have been associated with a number of serious health problems, including infertility, testicular dysgenesis, obesity, asthma, and allergies, as well as leiomyomas and breast cancer. Parabens, which can be dermally absorbed, are present in many cosmetic products, including antiperspirants. Their estrogenicity and tissue presence are a cause for concern regarding breast cancer. Fortunately, these compounds are relatively easy to avoid and such steps can result in dramatic reductions of urinary levels of these compounds.

  13. Effect of heating rate on toxicity of pyrolysis gases from some synthetic polymers

    Science.gov (United States)

    Hilado, C. J.; Soriano, J. A.; Kosola, K. L.

    1977-01-01

    The effect of heating rate on the toxicity of the pyrolysis gases from some synthetic polymers was investigate, using a screening test method. The synthetic polymers were polyethylene, polystyrene, polymethyl methacrylate, polycarbonate, ABS, polyaryl sulfone, polyether sulfone, and polyphenylene sulfide. The toxicants from the sulfur-containing polymers appeared to act more rapidly than the toxicants from the other polymers. It is not known whether this effect is due primarily to differences in concentration or in the nature of the toxicants. The carbon monoxide concentrations found do not account for the observed results.

  14. Consensus definitions of 14 severe acute toxic effects for childhood lymphoblastic leukaemia treatment

    DEFF Research Database (Denmark)

    Schmiegelow, K.; Attarbaschi, Andishe; Barzilai, Shlomit

    2016-01-01

    Although there are high survival rates for children with acute lymphoblastic leukaemia, their outcome is often counterbalanced by the burden of toxic effects. This is because reported frequencies vary widely across studies, partly because of diverse definitions of toxic effects. Using the Delphi ...

  15. 40 CFR 159.184 - Toxic or adverse effect incident reports.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Toxic or adverse effect incident reports. 159.184 Section 159.184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Information § 159.184 Toxic or adverse effect incident reports. (a) General. Information about incidents...

  16. Lethal and sub-lethal responses of native freshwater mussels exposed to granular Bayluscide®, a sea lamprey larvicide

    Science.gov (United States)

    Newton, Teresa; Boogaard, Michael A.; Gray, Brian R.; Hubert, Terrance D.; Schloesser, Nicholas

    2017-01-01

    The invasive sea lamprey (Petromyzon marinus) poses a substantial threat to fish communities in the Great Lakes. Efforts to control sea lamprey populations typically involve treating tributary streams with lampricides on a recurring cycle. The presence of a substantial population of larval sea lampreys in the aquatic corridor between Lakes Huron and Erie prompted managers to propose a treatment using the granular formulation of Bayluscide® that targets larval sea lampreys that reside in sediments. However, these treatments could cause adverse effects on native freshwater mussels—imperiled animals that also reside in sediments. We estimated the risk of mortality and sub-lethal effects among eight species of adult and sub-adult mussels exposed to Bayluscide® for durations up to 8 h to mimic field applications. Mortality was appreciable in some species, especially in sub-adults (range, 23–51%). The lethal and sub-lethal effects were positively associated with the duration of exposure in most species and life stage combinations. Estimates of the median time of exposure that resulted in lethal and sub-lethal effects suggest that sub-adults were often affected by Bayluscide® earlier than adults. Siphoning activity and burrowing position of mussels during exposure may have moderated the uptake of Bayluscide® and may have influenced lethal and sub-lethal responses. Given that the various species and life stages were differentially affected, it will be difficult to predict the effects of Bayluscide® treatments on mussels.

  17. Effect of Microbial inoculation in combating the aluminium toxicity effect on growth of Zea mays.

    Science.gov (United States)

    Arora, P; Singh, G; Tiwari, A

    2017-07-31

    The present study is aimed at improving the aluminium tolerance in maize crop employing the potential of microbial inoculants in conferring resistance to these toxicities via production of certain chelating compounds like siderophores, exopolysachharides and organic acids. Acid soils have now-a-days become one of the key factors for limiting growth of many agriculturally important crops. Aluminium  is one of the major elements present in acid soils and is mainly responsible for toxicity in the soil. This aluminium is rapidly soluble in soil water and hence absorbed by plant roots under conditions where soil pH is below 5. This toxicity leads to severe root growth inhibition, thereby limiting the production of maize crops. It was observed that use of microbial inoculums can be helpful in elimination of these toxic compounds and prevent the inhibition of root growth . It was found that the soils contaminated with aluminium toxicity decreased the root length of maize plant significantly by 65% but Bacillus and Burkholderia inoculation increased this root length significantly by 1.4- folds and 2- folds respectively thereby combating the effect of aluminium toxicity. Aluminium concentration was found maximum in roots of plants which were grown under aluminium stress condition. But this aluminium accumulation decreased ̴ 2-folds when Burkholderia was used as seed inoculants under aluminium stress conditions. Also, at 60mM aluminium accumulation, phosphorus solubilisation in roots was found to be increased upto 30% on Burkholderia inoculation. However, Bacillus inoculation didn't show any significant difference in either of the case. Thus, the inoculation of seeds with Burkholderia isolates could prove to be a boon in sequestering aluminium toxicity in Zea mays.

  18. Effectiveness of Radioiodine Treatment for Toxic Nodular Goiter

    Directory of Open Access Journals (Sweden)

    Hatice Şakı

    2015-10-01

    Full Text Available Objective: The aim of this retrospective study is to evaluate the treatment outcomes in patients with toxic nodular goiter (TNG that received radioiodine treatment (RAIT and to determine the influence of age, gender, nodule size, I-131 dose, underlying etiology and antithyroid drugs on the outcomes of RAIT. Methods: Two hundred thirty three patients (mean 64±10 years old with TNG that received RAIT were included in the study. Treatment success was analyzed according to demographic (age and gender and clinical data (thyroid function tests before and after RAIT, thyroid sonography and scintigraphy, I-131 dose, antithyroid drugs. A fixed dose of 555 MBq was administered to patients with nodules smaller than 2 cm in diameter and of 740 MBq to patients with nodules larger than 2 cm. Hyperthyroidism treatment success was defined as achieving hypothyroidism or euthyroidism six months after RAIT. Results: In our study, the cure rate was 93.9% six months after RAIT. Hypothyroidism was observed in 74 (31.7% patients, and euthyroidism was achieved in 145 (62.2% patients while 14 (6% patients remained in hyperthyroid state. Age and gender did not affect treatment outcomes. No correlation was found between underlying etiology or antithyroid drugs and therapeutic effectiveness. The effectiveness of RAIT was better in patients with nodules smaller than 2 cm. Conclusion: We observed that high cure rates were obtained in patients with TNG with 555 MBq and 740 MBq doses of I-131. While nodule diameter and RAI dose are important factors for treatment efficacy; age, gender, underlying etiology and antithyroid drugs do not affect the outcome of RAIT.

  19. Methods of analysis in terms of effects and their application to toxic organic constituents of industrial waste water; Methoden und Anwendung der wirkungsbezogenen Analytik auf toxische organische Inhaltsstoffe in industriellen Abwaessern

    Energy Technology Data Exchange (ETDEWEB)

    Reemtsma, T.; Putschew, A.; Jekel, M. [Technische Univ. Berlin (Germany). Fachgebiet Wasserreinhaltung

    1999-07-01

    Coupling biological action detection with chemical sewage analysis opens up a broad spectrum of methods involving diverse amounts of effort, whose results can range from hints to ways of eliminating a toxic effect to the identification and quantification of individual toxic constituents even in complex waste water. These methods help recognizing problems with effluent quality and enhancing treatment concepts. As possible biological effects of sewage discharges into receiving bodies of water (including sublethal effects) are meeting with increasing attention, the importance of sewage analysis in terms of effects will acquire even greater weight. Automated and miniaturized processes can cut down the involved effort substantially in the future. (orig.) [German] Die Kopplung der biologischen Wirkungsdetektion mit chemischer Abwasseranalytik eroeffnet ein breites Spektrum unterschiedlich aufwendiger Methoden, deren Ergebnisse von Hinweisen auf Methoden zur Entfernung einer toxischen Wirkung bis zur Identifizierung und Quantifizierung einzelner toxischer Inhaltsstoffe auch in komplexer Abwaessern reichten koennen. Diese Methoden helfen beim Erkennen von Problemen in der Ablaufqualitaet und unterstuetzen bei der Verbesserung von Behandlungskonzepten. Mit steigender Beachtung moeglicher biologischer Wirkungen von Abwassereinleitungen im Vorfluter (unter Einbeziehung sublethaler Effekte) wird die Bedeutung der wirkungsbezogenen Abwasseranalytik noch zunehmen. Automatisierte und miniaturisierte Verfahren koennen zukuenftig den dabei zu treibenden Aufwand wesentlich vermindern. (orig.)

  20. Boron Toxicity Causes Multiple Effects on Malus domestica Pollen Tube Growth

    OpenAIRE

    Kefeng eFang; Weiwei eZhang; Yu eXing; Qing eZhang; Liu eYang; Qingqin eCao; Ling eQin

    2016-01-01

    Boron is an important micronutrient for plants. However, boron is also toxic to cells at high concentrations, although the mechanism of this toxicity is not known. This study aimed to evaluate the effect of boron toxicity on Malus domestica pollen tube growth and its possible regulatory pathway. Our results showed that a high concentration of boron inhibited pollen germination and tube growth and led to the morphological abnormality of pollen tubes. Fluorescent labeling coupled with a scannin...

  1. Sublethal triclosan exposure decreases susceptibility to gentamicin and other aminoglycosides in Listeria monocytogenes.

    Science.gov (United States)

    Christensen, Ellen G; Gram, Lone; Kastbjerg, Vicky G

    2011-09-01

    The human food-borne pathogen Listeria monocytogenes is capable of persisting in food processing plants despite cleaning and sanitation and is likely exposed to sublethal biocide concentrations. This could potentially affect susceptibility of the bacterium to biocides and other antimicrobial agents. The purpose of the present study was to determine if sublethal biocide concentrations affected antibiotic susceptibility in L. monocytogenes. Exposure of L. monocytogenes strains EGD and N53-1 to sublethal concentrations of Incimaxx DES (containing peroxy acids and hydrogen peroxide) and Triquart Super (containing quaternary ammonium compound) in four consecutive cultures did not alter the frequency of antibiotic-tolerant isolates, as determined by plating on 2× the MIC for a range of antibiotics. Exposure of eight strains of L. monocytogenes to 1 and 4 μg/ml triclosan did not alter triclosan sensitivity. However, all eight strains became resistant to gentamicin (up to 16-fold increase in MIC) after exposure to sublethal triclosan concentrations. Gentamicin-resistant isolates of strains N53-1 and 4446 were also resistant to other aminoglycosides, such as kanamycin, streptomycin, and tobramycin. Gentamicin resistance remained at a high level also after five subcultures without triclosan or gentamicin. Aminoglycoside resistance can be caused by mutations in the target site, the 16S rRNA gene. However, such mutations were not detected in the N53-1-resistant isolates. A combination of gentamicin and ampicillin is commonly used in listeriosis treatment. The triclosan-induced resistance is, hence, of great concern. Further investigations are needed to determine the molecular mechanisms underlying the effect of triclosan.

  2. Sublethal Triclosan Exposure Decreases Susceptibility to Gentamicin and Other Aminoglycosides in Listeria monocytogenes▿

    Science.gov (United States)

    Christensen, Ellen G.; Gram, Lone; Kastbjerg, Vicky G.

    2011-01-01

    The human food-borne pathogen Listeria monocytogenes is capable of persisting in food processing plants despite cleaning and sanitation and is likely exposed to sublethal biocide concentrations. This could potentially affect susceptibility of the bacterium to biocides and other antimicrobial agents. The purpose of the present study was to determine if sublethal biocide concentrations affected antibiotic susceptibility in L. monocytogenes. Exposure of L. monocytogenes strains EGD and N53-1 to sublethal concentrations of Incimaxx DES (containing peroxy acids and hydrogen peroxide) and Triquart Super (containing quaternary ammonium compound) in four consecutive cultures did not alter the frequency of antibiotic-tolerant isolates, as determined by plating on 2× the MIC for a range of antibiotics. Exposure of eight strains of L. monocytogenes to 1 and 4 μg/ml triclosan did not alter triclosan sensitivity. However, all eight strains became resistant to gentamicin (up to 16-fold increase in MIC) after exposure to sublethal triclosan concentrations. Gentamicin-resistant isolates of strains N53-1 and 4446 were also resistant to other aminoglycosides, such as kanamycin, streptomycin, and tobramycin. Gentamicin resistance remained at a high level also after five subcultures without triclosan or gentamicin. Aminoglycoside resistance can be caused by mutations in the target site, the 16S rRNA gene. However, such mutations were not detected in the N53-1-resistant isolates. A combination of gentamicin and ampicillin is commonly used in listeriosis treatment. The triclosan-induced resistance is, hence, of great concern. Further investigations are needed to determine the molecular mechanisms underlying the effect of triclosan. PMID:21746948

  3. Towards the prevention of potential aluminum toxic effects and an effective treatment for Alzheimer's disease.

    Science.gov (United States)

    Percy, Maire E; Kruck, Theo P A; Pogue, Aileen I; Lukiw, Walter J

    2011-11-01

    In 1991, treatment with low dose intramuscular desferrioxamine (DFO), a trivalent chelator that can remove excessive iron and/or aluminum from the body, was reported to slow the progression of Alzheimer's disease (AD) by a factor of two. Twenty years later this promising trial has not been followed up and why this treatment worked still is not clear. In this critical interdisciplinary review, we provide an overview of the complexities of AD and involvement of metal ions, and revisit the neglected DFO trial. We discuss research done by us and others that is helping to explain involvement of metal ion catalyzed production of reactive oxygen species in the pathogenesis of AD, and emerging strategies for inhibition of metal-ion toxicity. Highlighted are insights to be considered in the quests to prevent potentially toxic effects of aluminum toxicity and prevention and intervention in AD. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Effect of Acute Toxicity of Cadmium in Mice Kidney Cells

    Directory of Open Access Journals (Sweden)

    Masoomeh Masoomi Karimi

    2012-11-01

    Full Text Available Background: Cadmium is one of the most toxic heavy metals in our environment having a very strong ability to accumulate in body organs, especially in kidney. The present study was done to determine the genotoxicity and cytotoxicity in kidneys of rats exposed to cadmium. Methods: Male rats (n=30, kept in standard conditions were used in this study. The animals were randomly divided into 2 groups (control and treatment. The treatment group was intraperitoneally injected with Cd (300µm/kg at hours 0, 6, 12, 24, 48. Twenty four hours after the last injection, the rats were sacrificed and their kidneys were obtained. Then oxidative stress markers, malondialdehide (MDA, glutathione (GSH, and superoxide dismutase (SOD, were assayed in homogenized kidney for studying their cytotoxicity. For genotoxicity and DNA damage studies, Comet assay was run on isolated kidney cells. Data analysis was done by t-test and ANOVA using SPSS software version 15. Results: MDA and GSH concentrations in normal and Cd exposed kidney cells were 287.01±37.30nmol/g.pr and 15.61±3.89µmol/g.pr and 609.24±87.87nmol/g.pr and 28.52±5.22µmol/g.pr, respectively. In addition, SOD activity in normal and Cd exposed kidney cells were 77.75±4.12 and 218.91±5.40 U/mg.pr, respectively. Comet assay results (content comet length, tail length, and head diameter showed DNA breakage in the treatment group that was stimulated by Cd which was not seen in the control group. Conclusion: The results demonstrated the genotoxicity effect of Cd on kidney cells as well as the ability of Cd to producing cytotoxicity.

  5. Sublethal RNA Oxidation as a Mechanism for Neurodegenerative Disease

    Directory of Open Access Journals (Sweden)

    Mark A. Smith

    2008-05-01

    Full Text Available Although cellular RNA is subjected to the same oxidative insults as DNA and other cellular macromolecules, oxidative damage to RNA has not been a major focus in investigations of the biological consequences of free radical damage. In fact, because it is largely single-stranded and its bases lack the protection of hydrogen bonding and binding by specific proteins, RNA may be more susceptible to oxidative insults than is DNA. Oxidative damage to protein-coding RNA or non-coding RNA will, in turn, potentially cause errors in proteins and/or dysregulation of gene expression. While less lethal than mutations in the genome, such sublethal insults to cells might be associated with underlying mechanisms of several chronic diseases, including neurodegenerative disease. Recently, oxidative RNA damage has been described in several neurodegenerative diseases including Alzheimer disease, Parkinson disease, dementia with Lewy bodies, and prion diseases. Of particular interest, oxidative RNA damage can be demonstrated in vulnerable neurons early in disease, suggesting that RNA oxidation may actively contribute to the onset of the disease. An increasing body of evidence suggests that, mechanistically speaking, the detrimental effects of oxidative RNA damage to protein synthesis are attenuated, at least in part, by the existence of protective mechanisms that prevent the incorporation of the damaged ribonucleotides into the translational machinery. Further investigations aimed at understanding the processing mechanisms related to oxidative RNA damage and its consequences may provide significant insights into the pathogenesis of neurodegenerative and other degenerative diseases and lead to better therapeutic strategies.

  6. Toxicity of copper and zinc to Puntius parrah (Day, 1865).

    Science.gov (United States)

    Ciji, P P; Bijoy Nandan, S

    2014-02-01

    The toxicities of the trace metals copper and zinc on the fish Puntius parrah were assessed based on standard renewal bioassay methods, and the 96 h LC50 values for copper and zinc were 0.5 mg/L and 9 mg/L, respectively. The zinc and copper concentrations in water and sediment were high in a highly industrialized area compared with those in non-industrialized zones of the Periyar River. The fish exposed to a sublethal concentration of 0.05 mg/L of Cu and 0.9 mg/L of Zn showed a higher accumulation of both of the metals in the liver than in the kidneys, gills, and muscles. The histological changes induced by copper and zinc on the test organism under sublethal concentrations on the 3rd, 7th, 14th, and 28th -days of exposure were also studied. There was a significant decrease (p water bodies and aquatic organisms from trace metal pollution and its toxic effects. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Toxic Effects of a Whole-Body Inhalation Sarin (GR) Vapor Exposure in the Gottingen Minipig

    National Research Council Canada - National Science Library

    Hulet, S. W; Jakubowski, E. M; Dabisch, P. A; Foster, J. S; Miller, D. B; Benton, B. J; Muse, W. T; Way, R. A; Edwards, J. L; McGuire, J.M

    2004-01-01

    ...; from the first noticeable effect (miosis) to potentially fatal effects of inhalation exposure. Although there are numerous published works investigating the progression of toxic signs elicited by sarin (GB...

  8. Toxicity assessment in marine sediment for the Terra Nova environmental effects monitoring program (1997-2010)

    Science.gov (United States)

    Whiteway, Sandra A.; Paine, Michael D.; Wells, Trudy A.; DeBlois, Elisabeth M.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Janes, G. Gregory

    2014-12-01

    This paper discusses toxicity test results on sediments from the Terra Nova offshore oil development. The Terra Nova Field is located on the Grand Banks approximately 350 km southeast of Newfoundland (Canada). The amphipod (Rhepoxynius abronius) survival and solid phase luminescent bacteria (Vibrio fischeri, or Microtox) assays were conducted on sediment samples collected from approximately 50 stations per program year around Terra Nova during baseline (1997), prior to drilling, and in 2000, 2001, 2002, 2004, 2006, 2008 and 2010 after drilling began. The frequency of toxic responses in the amphipod toxicity test was low. Of the ten stations that were toxic in environmental effects monitoring (EEM) years, only one (station 30(FE)) was toxic in more than one year and could be directly attributed to Terra Nova project activities. In contrast, 65 (18%) of 364 EEM samples were toxic to Microtox. Microtox toxicity in EEM years was not related to distance from Terra Nova drill centres or concentrations of >C10-C21 hydrocarbons or barium, the primary constituents of the synthetic-based drill muds used at Terra Nova. Of the variables tested, fines and strontium levels showed the strongest (positive) correlations with toxicity. Neither fines nor strontium levels were affected by drill cuttings discharge at Terra Nova, except at station 30(FE) (and that station was not toxic to Microtox). Benthic macro-invertebrate abundance, richness and diversity were greater in toxic than in non-toxic sediments. Therefore, Microtox responses indicating toxicity were associated with positive biological responses in the field. This result may have been an indirect function of the increased abundance of most invertebrate taxa in less sandy sediments with higher gravel content, where fines and strontium levels and, consequently, toxicity to Microtox were high; or chemical substances released by biodegradation of organic matter, where invertebrates are abundant, may be toxic to Microtox. Given

  9. Lethal and sub-lethal selectivity of fenbutatin oxide and sulfur to the predator Iphiseiodes zuluagai (Acari: Phytoseiidae) and its prey, Oligonychus ilicis (Acari: Tetranychidae), in Brazilian coffee plantations.

    Science.gov (United States)

    Teodoro, Adenir V; Fadini, Marcos A M; Lemos, Walkymário P; Guedes, Raul Narciso C; Pallini, Angelo

    2005-01-01

    Lethal concentration (LC) has been widely used to estimate pesticide toxicity. However, it does not consider the sub-lethal effects. Therefore we included the instantaneous rate of increase in association with LC to estimate population-level effects of the acaricides fenbutatin oxide and sulfur on the predator Iphiseiodes zuluagai and its prey, the phytophagous southern red mite, Oligonychus ilicis. The predator was 32.84x and 17.20x more tolerant to fenbutatin oxide and sulfur, respectively, than its prey, based on LC50 estimates obtained from acute concentration-mortality bioassays. The instantaneous rate of population growth in both mite species decreased with increasing acaricide concentration. Both acaricides provided effective control of O. ilicis at their recommended concentrations, but sulfur drastically compromised the predator populations quickly leading them to extinction due to the low reproductive potential of this species compared with its prey.

  10. acute toxicity and effect of fenitrothion on liver esterase of fish

    African Journals Online (AJOL)

    Preferred Customer

    ACUTE TOXICITY AND EFFECT OF FENITROTHION ON LIVER ESTERASE OF FISH. Solomon Sorsa. Department of Biology, Awassa College of Teacher Education. PO Box 115, Awassa, E-mail: solomonsorsa@yahoo.com. ABSTRACT: The acute toxicity of fenitrothion (FNT) alone and combined with piperonyl butoxide.

  11. Acute-lethal toxicity (LC50) effect of Moringa oleifera (Lam.) Fresh ...

    African Journals Online (AJOL)

    SH

    aquaculture. This study assessed the acute-lethal toxicity (LC50) effect of Moringa oleifera fresh root-bark extract on fresh water fish, Oreochromis niloticus juveniles for 96-h under renewal toxicity exposure. Median. Lethal Concentration (LC50) for O. niloticus juvenile was 97.61 mgl-1 and high mortality was obtained at 200.

  12. Effect of age and body weight on toxicity and survival in pediatric acute myeloid leukemia

    DEFF Research Database (Denmark)

    Løhmann, Ditte J A; Abrahamsson, Jonas; Ha, Shau-Yin

    2016-01-01

    Treatment for pediatric acute myeloid leukemia is very toxic and the association between outcome and age and Body Mass Index is unclear. We investigated effect of age and Body Mass Index on toxicity and survival in pediatric acute myeloid leukemia. We studied all patients who completed first...

  13. Toxicity of Methylcyclohexane and Its Effect on the Reproductive System in SD Rats

    Directory of Open Access Journals (Sweden)

    Hyeon-Yeong Kim

    2011-09-01

    Conclusion: When injected repeatedly for 13 weeks, methylcyclohexane proved to be toxic for the liver, heart, and kidney at a high dose. The absolute toxic dose was 1,000 mg/kg/day, while the no observed adverse effect level was less than 100 mg/kg/day. The substance exerted little influence on the reproductive system.

  14. Toxic effects of formalin-treated cadaver on medical students, staff ...

    African Journals Online (AJOL)

    Background: Formaldehyde can be toxic, allergenic and carcinogenic. Evaporation of formaldehyde from formalin-treated cadavers in the anatomy dissection rooms can produce high exposure. This study was conducted to assess acute and chronic toxic effects of formalin-treated cadavers on medical students, staff ...

  15. How might selenium moderate the toxic effects of mercury in stream fish of the Western USA?

    Science.gov (United States)

    The ability of selenium (Se) to moderate mercury (Hg) toxicity is well established in the literature. Mercury exposures that might otherwise produce toxic effects are counteracted by Se, particularly when Se:Hg molar ratios approach or exceed 1. We analyzed whole body Se and Hg c...

  16. Toxic effects of formalin-treated cadaver on medical students, staff ...

    African Journals Online (AJOL)

    Noha Selim Mohamed Elshaer

    2017-01-02

    Jan 2, 2017 ... Background: Formaldehyde can be toxic, allergenic and carcinogenic. Evaporation of formaldehyde from formalin-treated cadavers in the anatomy dissection rooms can produce high exposure. This study was conducted to assess acute and chronic toxic effects of formalin-treated cadavers on medical ...

  17. Do diosgenin ameliorate urinary bladder toxic effect of ...

    African Journals Online (AJOL)

    SWEET

    2012-01-26

    Jan 26, 2012 ... Aqueous extract of walnut (Juglans regia L) protects mice against cyclophosphamide-induced biochemical toxicity. Hum. Exp. Toxicol. 22: 473-480. Hengstler JG, Hengst A, Fuchs J, Tanner B, Phol J, Oesch F (1997). Induction of DNA crosslinks and DNA strand lesions by cyclophosphamide after activation ...

  18. Effect of fruiting on micronutrients, antinutrients and toxic substances ...

    African Journals Online (AJOL)

    use

    of T. occidentalis at vegetative phase (market maturity) reduces the levels of most of the plant toxins and still retain most of the ... Key words: Telfairia occidentalis, anti-nutrients, toxic substances, micronutrients, market maturity and fruiting, soil nitrogen levels. ..... nitrate in baby food: Collaborative study. J. AOAC Int., 77(2): ...

  19. Acute toxicity effects of the aqueous leaf extract of Anogeissus ...

    African Journals Online (AJOL)

    Using the intraperitoneal route, the rats showed dose-dependent signs of toxicity ranging from inappetence, depression, unsteady gait, tremors, and respiratory distress to death. The I/P LD50 was 1400 mg/kg body weight. No gross changes were observed in the organs of rats that died following extract administration.

  20. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors...... to human exposure. The occurrence of each element in food classes from different regions is presented. Some of the current toxicological risk assessments on toxic elements, the human health effect of each toxic element, and their contents in the food legislations are presented. An overview of analytical...... techniques and challenges for determination of toxic elements in food is also given....

  1. Effectiveness of selenium on acrylamide toxicity to retina

    Directory of Open Access Journals (Sweden)

    Mervat Ahmed Ali

    2014-08-01

    of the retina didn’t change compared to control due to Se treatment.CONCLUSION: This study provides evidence for the protective effect of Se on acrylamide induced toxicity by reducing oxidative stress.

  2. Nuclear morphology and lysosomal stability of molluskan hemocytes as possible biomarkers of arsenic toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Sudipta [Post Graduate Department of Zoology, Parasitology and Medical Entomology Laboratory, Darjeeling Government College, Darjeeling (India); Ray, Sajal [Department of Zoology, Aquatic Toxicology Laboratory, University of Calcutta, Kolkata (India)

    2009-10-15

    The frequency of nuclear aberrations and neutral red retention time of hemocytes in the mollusk Lamellidens marginalis were recorded under exposure to sublethal concentrations of sodium arsenite in order to examine the sensitivity and effectiveness of these inexpensive assays for screening the toxicity of As{sup 3+}in a freshwater ecosystem. A dose and time dependent increase in the density of micronucleated and binucleated hemocytes and gill cells was indicative of the pronounced genotoxic effect of arsenic on this animal. The disruption of intrahemocyte homeostasis imposed by this natural toxicant was evident from a dose and time dependent reduction in the lysosomal stability of the hemocytes of the animal. The tested parameters are indicative of arsenic toxicity in L. marginalis in the freshwater systems of the arsenic affected geographical areas of West Bengal, India. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  3. {sup 1}H NMR metabolomics of earthworm exposure to sub-lethal concentrations of phenanthrene in soil

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Sarah A.E.; McKelvie, Jennifer R.; Simpson, Andre J. [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, Ontario, M1C 1A4 (Canada); Simpson, Myrna J., E-mail: myrna.simpson@utoronto.c [Department of Physical and Environmental Sciences, University of Toronto, 1265 Military Trail Toronto, Ontario, M1C 1A4 (Canada)

    2010-06-15

    {sup 1}H NMR metabolomics was used to monitor earthworm responses to sub-lethal (50-1500 mg/kg) phenanthrene exposure in soil. Total phenanthrene was analyzed via soxhlet extraction, bioavailable phenanthrene was estimated by hydroxypropyl-beta-cyclodextrin (HPCD) and 1-butanol extractions and sorption to soil was assessed by batch equilibration. Bioavailable phenanthrene (HPCD-extracted) comprised approx65-97% of total phenanthrene added to the soil. Principal component analysis (PCA) showed differences in responses between exposed earthworms and controls after 48 h exposure. The metabolites that varied with exposure included amino acids (isoleucine, alanine and glutamine) and maltose. PLS models indicated that earthworm response is positively correlated to both total phenanthrene concentration and bioavailable (HPCD-extracted) phenanthrene in a freshly spiked, unaged soil. These results show that metabolomics is a powerful, direct technique that may be used to monitor contaminant bioavailability and toxicity of sub-lethal concentrations of contaminants in the environment. These initial findings warrant further metabolomic studies with aged contaminated soils. - {sup 1}H NMR metabolomics is used to directly monitor metabolic responses of Eisenia fetida after 48 h of exposure to sub-lethal concentrations of phenanthrene in soil.

  4. Decreased Dissolution of ZnO by Iron Doping Yields Nanoparticles with Reduced Toxicity in the Rodent Lung and Zebrafish Embryos

    OpenAIRE

    Xia, Tian; Zhao, Yan; Sager, Tina; George, Saji; Pokhrel, Suman; Li, Ning; Schoenfeld, David; Meng, Huan; Lin, Sijie; Wang, Xiang; Wang, Meiying; Ji, Zhaoxia; Zink, Jeffrey I.; Mädler, Lutz; Castranova, Vincent

    2011-01-01

    We have recently shown that the dissolution of ZnO nanoparticles and Zn2+ shedding leads to a series of sub-lethal and lethal toxicological responses at cellular level that can be alleviated by iron-doping. Iron-doping changes the particle matrix and slows the rate of particle dissolution. To determine whether iron doping of ZnO also leads to lesser toxic effects in vivo, toxicity studies were performed in rodent and zebrafish models. First, we synthesized a fresh batch of ZnO nanoparticles d...

  5. Metal and pharmaceutical mixtures: Is ion loss the mechanism underlying acute toxicity and widespread additive toxicity in zebrafish?

    Energy Technology Data Exchange (ETDEWEB)

    Alsop, Derek, E-mail: alsopde@mcmaster.ca; Wood, Chris M.

    2013-09-15

    Highlights: •Zebrafish larvae were used to test the acute toxicity of contaminant mixtures. •Interactions were observed between metals, ammonia and pharmaceuticals. •Larval Na{sup +} loss was observed with exposure to all acutely toxic contaminants tested. •Water quality criteria should recognize the toxic interactions between contaminants. -- Abstract: The acute toxicities and mechanisms of action of a variety of environmental contaminants were examined using zebrafish larvae (Danio rerio; 4–8 days post fertilization). Toxic interactions were observed between metals. For example, the addition of a sublethal level of nickel (15% of the LC{sub 50}, one third of the LC{sub 01}) to all copper treatments decreased the copper 96 h LC{sub 50} by 58%, while sublethal copper exposure (6% of the copper LC{sub 50}, 13% of the LC{sub 01}) decreased the cadmium 96 h LC{sub 50} by 47%. Two predictive models were assessed, the concentration addition (CA) model, which assumes similar mechanisms of action, and the independent action (IA) model, which assumes different mechanisms of action. Quantitative comparisons indicated the CA model performed better than the IA model; the latter tended to underestimate combined toxicity to a greater extent. The effects of mixtures with nickel or ammonia were typically additive, while mixtures with copper or cadmium were typically greater than additive. Larvae exposed to cadmium, copper or nickel experienced whole body ion loss. Decreases were greatest for Na{sup +} followed by K{sup +} (as high as 19% and 9%, respectively, in 24 h). Additive toxicity between copper and other pharmaceutical compounds such as fluoxetine (Prozac™), β-naphthoflavone, estrogen and 17α-ethinylestradiol were also observed. Similar to metals, acutely toxic concentrations of fluoxetine, β-naphthoflavone and ammonia all decreased whole body Na{sup +} and K{sup +}. Overall, whole body Na{sup +} loss showed the greatest correlation with mortality across a

  6. Effects of calcium, magnesium, and sodium on alleviating cadmium toxicity to Hyalella azteca

    Science.gov (United States)

    Jackson, B.P.; Lasier, P.J.; Miller, W.P.; Winger, P.V.

    2000-01-01

    Toxicity of trace metal ions to aquatic organisms, arising through either anthropogenic inputs or acidification of surface waters, continues to be both a regulatory and environmental problem. It is generally accepted that the free metal ion is the major toxic species (Florence et a1.,1992) and that inorganic or organic complexation renders the metal ion non-bioavailable (Meador, 1991, Galvez and Wood, 1997). However, water chemistry parameters such as alkalinity, hardness, dissolved organic carbon and pH influence metal ion toxicity either directly by lowering free metal ion concentration or indirectly through synergistic or antagonistic effects. Alkalinity and salinity can affect the speciation of metal ions by increasing ion-pair formation, thus decreasing free metal ion concentration. For example, Cu was found to be less toxic to rainbow trout in waters of high alkalinity (Miller and Mackay, 1980), due to formation of CuCO3 ion pair, and corresponding reduction in free Cu2+ concentration. The influence of salinity on the toxicity of cadmium to various organisms has been demonstrated in a number of studies (Bervoets et al., 1995, Hall et al., 1995, Lin and Dunson, 1993, Blust et al., 1992). In all these studies the apparent toxicity of cadmium was lowered as salinity was increased due to increased formation of CdC1+ and CDCl2 aqueous complexes that are non-toxic or of much lower toxicity than the free Cd2+ ion. Changes in pH exert both a biological and chemical effect on metal ion toxicity (Campbell and Stokes, 1985). Low pH favors greater metal ion solubility, and, in the absence of complexing ions, reduced speciation of the metal ion, which tends to increase toxicity compared to higher pH. However, Iow pH also enhances competition between H+ and metal ion for cell surface binding sites, which tends to decrease metal ion toxicity.

  7. Toxic effects of combined effects of anthracene and UV radiation on Brachionus plicatilis

    Science.gov (United States)

    Gao, Ceng; Zhang, Xinxin; Xu, Ningning; Tang, Xuexi

    2017-05-01

    Anthracene is a typical polycyclic aromatic hydrocarbon, with photo activity, can absorb ultraviolet light a series of chemical reactions, aquatic organisms in the ecosystem has a potential light induced toxicity. In this paper, the effects of anthracene and UV radiation on the light-induced toxicity of Brachionus plicatilis were studied. The main methods and experimental results were as follows: (1) The semi-lethal concentration of anthracene in UV light was much lower than that in normal light, The rotifers have significant light-induced acute toxicity. (2) Under UV irradiation, anthracene could induce the increase of ROS and MDA content in B. plicatilis, and the activity of antioxidant enzymes in B. plicatilis significantly changed, Where SOD, GPx activity was induced within 24 hours of the beginning of the experiment. And the content of GPX and CAT was inhibited after 48 hours. Therefore, the anthracite stress induced by UV radiation could more strongly interfere with the ant oxidative metabolism of B. plicatilis, and more seriously cause oxidative damage, significant light-induced toxicity.

  8. Effects of toxic and non-toxic blue mussel meal on health and product quality of laying hens.

    Science.gov (United States)

    Jönsson, L; Holm, L

    2010-06-01

    Blue mussels (Mytilus edulis) are a potential protein source in poultry feeds because of their high methionine and cysteine content. However, mussels may temporarily be contaminated with the toxin, okadaic acid. The aim of this small scale study was to evaluate the effects on animal health and morphology of the digestive tract of laying hens fed three different diets; a commercial feed and diets containing 15% normal or 15% toxic mussel meal, i.e. a concentration of 198.6 microg toxin per kg feed. Twelve laying hens were divided into six groups and fed the experimental diets for 8 weeks. Animal health, production performance and egg quality were recorded. At sacrifice, tissue samples were prepared for histological evaluation using light microscopy. Okadaic acid did not have any adverse effects on animal health or production parameters and no histological changes indicating disturbances in the digestive tract was observed. Internal egg quality was improved as eggs from hens fed either of the two mussel meal diets had an increased yolk colour. These results show that mussel meal functions as a novel protein source for laying hens and those toxic mussels at this level may be included in the feed without negative effects on parameters evaluated in this study.

  9. Artificial saliva effect on toxic substances release from acrylic resins

    OpenAIRE

    Kostić Milena; Krunić Nebojša; Najman Stevo; Nikolić Ljubiša; Nikolić Vesna; Rajković Jelena; Petrović Milica; Igić Marko; Ignjatović Aleksandra

    2015-01-01

    Background/Aim. Acrylic-based resins are intensively used in dentistry practice as restorative or denture-base materials. The purpose of this study was to analyze the surface structure of denture base resins and the amount of released potentially toxic substances (PTS) immediately upon polymerization and incubation in different types of artificial saliva. Methods. Storage of acrylic samples in two models of artificial saliva were performed in a water bath a...

  10. Glioprotective Effects of Ashwagandha Leaf Extract against Lead Induced Toxicity

    OpenAIRE

    Praveen Kumar; Raghavendra Singh; Arshed Nazmi; Dinesh Lakhanpal; Hardeep Kataria; Gurcharan Kaur

    2014-01-01

    Withania somnifera (Ashwagandha), also known as Indian Ginseng, is a well-known Indian medicinal plant due to its antioxidative, antistress, antigenotoxic, and immunomodulatory properties. The present study was designed to assess and establish the cytoprotective potential of Ashwagandha leaf aqueous extract against lead induced toxicity. Pretreatment of C6 cells with 0.1% Ashwagandha extract showed cytoprotection against 25  μ M to 400 μ M concentration of lead nitrate. Further pretreatment w...

  11. Toxic effect of carbon tetrachloride on the liver of chicken

    Directory of Open Access Journals (Sweden)

    M. G. Saeed

    2009-01-01

    Full Text Available The aim of the present study was assessment of gross and microscopic pathological changes resulting from sub acute and sub chronic toxicity of carbon tetrachloride CCl4 (99.5% in the liver of chicken and its relation with serum alanine aminotransferase (ALT and aspartate aminotransferase (AST levels. The approximate lethal dose in three weeks old chickens was equal to (994 mg/kg i.p.. In the sub acute toxicity experiment the given dose was (497 mg/kg i.p. twice a week for one week, the liver of treated animals with CCl4 grossly appeared pale and mottled with white yellowish color patches represent the necrotic tissue, the histopathological changes was severe hepatitis with infiltration of inflammatory cells specially heterophiles and diffused coagulative necrosis. In sub chronic toxicity experiment the dose was given (248.5 mg/kg i.p. twice a week for eight weeks, in gross appearance the liver was severely congested, the histopathological changes was hypertrophy of hepatocytes, hyperplasia of lining epithelium of bile ducts and chronic venous congestion, growth depression and significant decreased in the body weight of the treated animals also noticed at this experiment in compared with control group, a significant increased in (ALT and (AST activities also recorded. The results suggests that pathological changes and response of the chicken’s liver to the CCl4 toxicity relatively differs from other laboratory animal models like rats and mice when used approximate dose in the same duration of exposure, so it didn’t appear fibrosis or cirrhosis of the liver of chickens, therefore it can't use chickens as a model to induce experimental fibrosis or liver cirrhosis when treated with CCl4 according to the dose and duration of exposure of this study.

  12. The Toxic Effects and Mechanisms of CuO and ZnO Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ya-Nan Chang

    2012-12-01

    Full Text Available Recent nanotechnological advances suggest that metal oxide nanoparticles (NPs have been expected to be used in various fields, ranging from catalysis and opto-electronic materials to sensors, environmental remediation, and biomedicine. However, the growing use of NPs has led to their release into environment and the toxicity of metal oxide NPs on organisms has become a concern to both the public and scientists. Unfortunately, there are still widespread controversies and ambiguities with respect to the toxic effects and mechanisms of metal oxide NPs. Comprehensive understanding of their toxic effect is necessary to safely expand their use. In this review, we use CuO and ZnO NPs as examples to discuss how key factors such as size, surface characteristics, dissolution, and exposure routes mediate toxic effects, and we describe corresponding mechanisms, including oxidative stress, coordination effects and non-homeostasis effects.

  13. Toxic effect of metal cation binary mixtures to the seaweed Gracilaria domingensis (Gracilariales, Rhodophyta).

    Science.gov (United States)

    Mendes, Luiz Fernando; Stevani, Cassius Vinicius; Zambotti-Villela, Leonardo; Yokoya, Nair Sumie; Colepicolo, Pio

    2014-01-01

    The macroalga Gracilaria domingensis is an important resource for the food, pharmaceutical, cosmetic, and biotechnology industries. G. domingensis is at a part of the food web foundation, providing nutrients and microelements to upper levels. As seaweed storage metals in the vacuoles, they are considered the main vectors to magnify these toxic elements. This work describes the evaluation of the toxicity of binary mixtures of available metal cations based on the growth rates of G. domingensis over a 48-h exposure. The interactive effects of each binary mixture were determined using a toxic unit (TU) concept that was the sum of the relative contribution of each toxicant and calculated using the ratio between the toxicant concentration and its endpoint. Mixtures of Cd(II)/Cu(II) and Zn(II)/Ca(II) demonstrated to be additive; Cu(II)/Zn(II), Cu(II)/Mg(II), Cu(II)/Ca(II), Zn(II)/Mg(II), and Ca(II)/Mg(II) mixtures were synergistic, and all interactions studied with Cd(II) were antagonistic. Hypotheses that explain the toxicity of binary mixtures at the molecular level are also suggested. These results represent the first effort to characterize the combined effect of available metal cations, based on the TU concept on seaweed in a total controlled medium. The results presented here are invaluable to the understanding of seaweed metal cation toxicity in the marine environment, the mechanism of toxicity action and how the tolerance of the organism.

  14. Toxicity of CeO2 nanoparticles - the effect of nanoparticle properties.

    Science.gov (United States)

    Leung, Yu Hang; Yung, Mana M N; Ng, Alan M C; Ma, Angel P Y; Wong, Stella W Y; Chan, Charis M N; Ng, Yip Hang; Djurišić, Aleksandra B; Guo, Muyao; Wong, Mabel Ting; Leung, Frederick C C; Chan, Wai Kin; Leung, Kenneth M Y; Lee, Hung Kay

    2015-04-01

    Conflicting reports on the toxicity of CeO2 nanomaterials have been published in recent years, with some studies finding CeO2 nanoparticles to be toxic, while others found it to have protective effects against oxidative stress. To investigate the possible reasons for this, we have performed a comprehensive study on the physical and chemical properties of nanosized CeO2 from three different suppliers as well as CeO2 synthesized by us, and tested their toxicity. For toxicity tests, we have studied the effects of CeO2 nanoparticles on a Gram-negative bacterium Escherichia coli in the dark, under ambient and UV illuminations. We have also performed toxicity tests on the marine diatom Skeletonema costatum under ambient and UV illuminations. We found that the CeO2 nanoparticle samples exhibited significantly different toxicity, which could likely be attributed to the differences in interactions with cells, and possibly to differences in nanoparticle compositions. Our results also suggest that toxicity tests on bacteria may not be suitable for predicting the ecotoxicity of nanomaterials. The relationship between the toxicity and physicochemical properties of the nanoparticles is explicitly discussed in the light of the current results. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Effect of culture medium on toxic effect of ZnO nanoparticles to freshwater microalgae

    Science.gov (United States)

    Aravantinou, Andriana F.; Tsarpali, Vasiliki; Dailianis, Stefanos; Manariotis, Ioannis D.

    2014-05-01

    The widely use of nanoparticles (NPs) in many products, is increasing over time. The release of NPs into the environment may affect ecosystems, and therefore it is essential to study their impact on aquatic organisms. The aim of this work was to investigate the effect of zinc oxide (ZnO) NPs on microalgae, cultured in different mediums. Chlorococcum sp. and Scenedesmus rubescens were used as freshwater microalgae model species in order to investigate the toxic effects of ZnO NPs. Microalgae species exposed to ZnO NPs concentrations varying from 0.081 to 810 mg/L for different periods of time (24 to 96 h) and two different culture mediums. The aggregation level and particle size distribution of NPs were also determined during the experiments. The experimental results revealed significant differences on algae growth rates depending on the selected culture medium. Specifically, the toxic effect of ZnO NPs in Chlorococcum sp. was higher in cultures with 1/3N BG-11 medium than in BBM medium, despite the fact that the dissolved zinc concentration was higher in BBM medium. On the other hand, Scenedesmus rubescens exhibited the exact opposite behavior, with the highest toxic effect in cultures with BBM medium. Both species growth was significantly affected by the exposure time, the NPs concentrations, and mainly the culture medium.

  16. Chronic and acute ammonia toxicity in mudskippers, Periophthalmodon schlosseri and Boleophthalmus boddaerti: brain ammonia and glutamine contents, and effects of methionine sulfoximine and MK801.

    Science.gov (United States)

    Ip, Yuen K; Leong, Mavis W F; Sim, Mei Y; Goh, Gillian S; Wong, Wai P; Chew, Shit F

    2005-05-01

    .9 micromol g(-1), respectively), while the glutamine level remained relatively low (3.93 and 2.67 micromol g(-1), respectively). Thus, glutamine synthesis and accumulation in the brain was not the major cause of death in these two mudskippers confronted with acute ammonia toxicity. Indeed, MSO, at a dosage (100 microg g(-1) fish) protective for rats, did not protect B. boddaerti against acute ammonia toxicity, although it was an inhibitor of GS activities from the brains of both mudskippers. In the case of P. schlosseri, MSO only prolonged the time to death but did not reduce the mortality rate (100%). In addition, MK801 (2 microg g(-1) fish) had no protective effect on P. schlosseri and B. boddaerti injected with a lethal dose of CH3COONH4, indicating that activation of NMDA receptors was not the major cause of death during acute ammonia intoxication. Thus, it can be concluded that there are major differences in mechanisms of chronic and acute ammonia toxicity between brains of these two mudskippers and mammalian brains.

  17. Toxicity and health effects of vehicle emissions in Shanghai

    Science.gov (United States)

    Ye, Shun-Hua; Zhou, Wei; Song, Jian; Peng, Bao-Cheng; Yuan, Dong; Lu, Yuan-Ming; Qi, Ping-Ping

    In China, the number of vehicles is increasing rapidly with the continuous development of economy, and vehicle emission pollution in major cities is more serious than ever. In this article, we summarized the results of a series of short-term assays, animal experiments and epidemiology investigations on the genotoxicity, immunotoxicity, respiratory toxicity and health effects of vehicle emissions in Shanghai, including gasoline exhausts (gas condensate and particles), diesel exhaust particles (DEP) and scooter exhaust particles (SEP). The results showed that: (1) Both gases and particulate phases of the exhausts of different kinds of vehicles showed strong mutagenicity in Ames test (TA98 and TA100 strains), rat hepatocyte unscheduled DNA synthesis (UDS) assay, and mouse micronucleus assay, and vehicle emissions could induce the transformation of Syrian hamster embryo (SHE) cells. DEP and SEP could induce the transformation of human diploid cell strain (KMB-13) cells, immunohistochemistry assay showed that c-myc and p21 proteins were highly expressed in the transformed cells. DEP and SEP could also inhibit the gap junctional intercellular communication (GJIC) of BALB/C3T3 cells (2) Vehicle emissions could decrease the number of macrophages in the lung (bronchial alveolar lavage fluid) (BALF) of male SD rats. Vehicle emissions could also increase the proportion of polymorphonuclear leukocytes (PMN), the content of cetyneuraminic acid (NA), the activity of lactate dehydrogenase (LDH), alkali phosphate (AKP), acid phosphate (ACP) in the lung BALF of the animals. (3) In epidemiology investigation, the proportion of those who have respiratory symptoms and chronic obstructive pulmonary diseases (COPD) in the workers who were exposed to DEP ( n=806) were much higher than those of the controls ( n=413). The OR (odd ratio) values of angina, nasal obstruction, phlegm, short of breath and COPD were 2.27, 3.08, 3.00, 3.19 and 2.32, respectively, and the proportion of those who

  18. Toxicity and health effects of vehicle emissions in Shanghai

    Energy Technology Data Exchange (ETDEWEB)

    Shunhua Ye; Wei Zhou; Jian Song; Baocheng Peng; Dong Yuan; Yuanming Lu; Pingping Qi [Shanghai Medical University (China). Dept. of Environmental Health

    2000-07-01

    In China, the number of vehicles is increasing rapidly with the continuous development of economy, and vehicle emission pollution in major cities is more serious than ever. In this article, we summarized the results of a series of short-term assays, animal experiments and epidemiology investigations on the genotoxicity, immunotoxicity, respiratory toxicity and health effects of vehicle emissions in Shanghai, including gasoline exhausts (gas condensate and particles), diesel exhaust particles (DEP) and scooter exhaust particles (SEP). The results showed that: (1) Both gases and particulate phases of the exhausts of different kinds of vehicles showed strong mutagenicity in Ames test (TA98 and TA100 strains), rat hepatocyte unscheduled DNA synthesis (UDS) assay, and mouse micronucleus assay, and vehicle emissions could induce the transformation of Syrian hamster embryo (SHE) cells. DEP and SEP could induce the transformation of human diploid cell strain (KMB-13) cells, immunohistochemistry assay showed that c-myc and p21 proteins were highly expressed in the transformed cells. DEP and SEP could also inhibit the gap junctional intercellular communication (GJIC) of BALB/C3T3 cells (2) Vehicle emissions could decrease the number of macrophages in the lung (bronchial alveolar lavage fluid) (BALF) of male SD rats. Vehicle emissions could also increase the proportion of polymorphonuclear leukocytes (PMN), the content of cetyneuraminic acid (NA), the activity of lactate dehydrogenase (LDH), alkali phosphate (AKP), acid phosphate (ACP) in the lung BALF of the animals. (3) In epidemiology investigation, the proportion of those who have respiratory symptoms and chronic obstructive pulmonary diseases (COPD) in the workers who were exposed to DEP (n = 806) were much higher than those of the controls (n = 413). The OR (odd ratio) values of angina, nasal obstruction, phlegm, short of breath and COPD were 2.27, 3.08, 3.00, 3.19 and 2.32, respectively, and the proportion of those who

  19. Effects of water quality parameters on boron toxicity to Ceriodaphnia dubia.

    Science.gov (United States)

    Dethloff, Gail M; Stubblefield, William A; Schlekat, Christian E

    2009-07-01

    The potential modifying effects of certain water quality parameters (e.g., hardness, alkalinity, pH) on the acute toxicity of boron were tested using a freshwater cladoceran, Ceriodaphnia dubia. By comparison, boron acute toxicity was less affected by water quality characteristics than some metals (e.g., copper and silver). Increases in alkalinity over the range tested did not alter toxicity. Increases in water hardness appeared to have an effect with very hard waters (>500 mg/L as CaCO(3)). Decreased pH had a limited influence on boron acute toxicity in laboratory waters. Increasing chloride concentration did not provide a protective effect. Boron acute toxicity was unaffected by sodium concentrations. Median acute lethal concentrations (LC(50)) in natural water samples collected from three field sites were all greater than in reconstituted laboratory waters that matched natural waters in all respects except for dissolved organic carbon. Water effect ratios in these waters ranged from 1.4 to 1.8. In subsequent studies using a commercially available source of natural organic matter, acute toxicity decreased with increased dissolved organic carbon, suggesting, along with the natural water studies, that dissolved organic carbon should be considered further as a modifier of boron toxicity in natural waters where it exceeds 2 mg/L.

  20. Response of larval fish, Leiostomus xanthurus, to environmental stress following sublethal cadmium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Middaugh, D.P.; Davis, W.R.; Yoakum, R.L.

    1975-08-01

    The toxicity of cadmium to larval fish, Leiostomus xanthurus, was studied. An incipient LC/sub 50/ concentration of approximately 0.2 to 0.3 mg/l cadmium was first estimated. Subsequent short-term sublethal tests were conducted to determine the relationship of cadmium exposure and accumulated whole body residues of the metal on the response of larvae to thermal stress and low dissolved oxygen. Results of this study indicated a significant decrease (..cap alpha.. = 0.05, t-Test) in the critical thermal maximum (CTM) for larvae exposed to 0.5 and 0.8 mg/l cadmium for 96 hours at 20/sup 0/C. Significant decreases (..cap alpha.. = 0.05, chi/sup 2/) in survival of larvae subjected to a dissolved oxygen (DO) level of 1.6 mg/l after exposure to 0.5 and 0.8 mg/l cadmium were also observed.

  1. Impact of sublethal concentration of triazophos on regulation of ...

    African Journals Online (AJOL)

    Exposure to sublethal doses of triazophos extract caused significant (p < 0.05) time and dose dependent reduction in the levels of total protein, acetylcholinesterase (AchE) and significant enhancement in the levels of total free amino acids, glutamine, adenosine monophosphate (AMP) deaminases, adenosine deaminases, ...

  2. Cardiovascular and Hepatic Toxicity of Cocaine: Potential Beneficial Effects of Modulators of Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Manuela Graziani

    2016-01-01

    Full Text Available Oxidative stress (OS is thought to play an important role in the pharmacological and toxic effects of various drugs of abuse. Herein we review the literature on the mechanisms responsible for the cardiovascular and hepatic toxicity of cocaine with special focus on OS-related mechanisms. We also review the preclinical and clinical literature concerning the putative therapeutic effects of OS modulators (such as N-acetylcysteine, superoxide dismutase mimetics, nitroxides and nitrones, NADPH oxidase inhibitors, xanthine oxidase inhibitors, and mitochondriotropic antioxidants for the treatment of cocaine toxicity. We conclude that available OS modulators do not appear to have clinical efficacy.

  3. How toxic is oil? Investigating specific receptor-mediated toxic effects of crude and refined oils

    NARCIS (Netherlands)

    Vrabie, C.M.|info:eu-repo/dai/nl/304836109

    2011-01-01

    Crude oils and refined oil products are major pollutants of the environment. Large oil spills, such as the recent blowout of the Deepwater Horizon in the Gulf of Mexico, raise concerns about the long term health effects of petroleum hydrocarbon exposure on wildlife and humans. In the environmental

  4. Assessment of acute and subacute toxic effects of the Saudi folk herb Retama raetam in rats

    Directory of Open Access Journals (Sweden)

    Mardi M. Algandaby

    2015-12-01

    Conclusion: Repeated administration of methanolic extract of RR (250 mg/kg has a low nephrotoxic subacute toxicity potential, while it might have hepatotoxic, nephrotoxic, and mutagenic effects at higher doses.

  5. Acute toxicity and effect of some petroleum hydrocarbon on the metabolic index in Etroplus suratensis

    Digital Repository Service at National Institute of Oceanography (India)

    Ansari, Z.A.; Farshchi, P.

    Acute toxicity (LC sub(50)) and effect of some petroleum hydrocarbons (Toluene, Quinoline, Pyridine and Naphthalene) on the metabolic index (oxygen consumption rate) of an estuarine fish. Etroplus suratensis is reported. The LC sub(50) values were...

  6. Webinar Presentation: Epidemiologic Studies of the Effects of Toxic Exposures on Brain and Behavior: Neuropsychological Assessment

    Science.gov (United States)

    This presentation, Epidemiologic Studies of the Effects of Toxic Exposures on Brain and Behavior: Neuropsychological Assessment, was given at the NIEHS/EPA Children's Centers 2015 Webinar Series: Interdisciplinary Approaches to Neurodevelopment.

  7. Webinar Presentation: Vitamins, Minerals and Metals: Do Healthy Diets Counteract Health Effects of Toxicants?

    Science.gov (United States)

    This presentation, Vitamins, Minerals and Metals: Do Healthy Diets Counteract Health Effects of Toxicants?, was given at the NIEHS/EPA Children's Centers 2015 Webinar Series: Food and Children's Health held on Dec. 9, 2015.

  8. Discourses on the Toxic Effects of Internal Chemical Contamination in Catalonia, Spain.

    Science.gov (United States)

    Larrea-Killinger, Cristina; Muñoz, Araceli; Mascaró, Jaume; Zafra, Eva; Porta, Miquel

    2017-01-01

    Human exposure to and contamination by environmental toxic compounds generates discourses and practices that merit greater attention. In this article, we assess internal chemical contamination and the risk of toxic effects as an experience related to the production of meaning in everyday life. Drawing on the analysis of semantic networks of narratives from semi-structured interviews conducted with 43 informants in Catalonia, Spain, we consider participants' perceptions of the health risks of toxic compounds, including social discourses on exposure, toxicity, and internal chemical contamination, and on responsibilities, consequences, and proposed strategies for controlling toxic compounds. Informants' narratives on the relationships between nature and nurture suggest that they no longer perceive rigid boundaries separating the human body from the external environment and its chemical pollutants.

  9. Joint Toxicity of Lead, Chromium, Cobalt and Nickel to Photobacterium phosphoreum at No Observed Effect Concentration.

    Science.gov (United States)

    Zeng, Yaling; Wang, Lan; Jiang, Long; Cai, Xiaoyu; Li, Yu

    2015-08-01

    Joint toxicity of Pb2+, Cr3+, Co2+ and Ni2+ toward Photobacterium phosphoreum (Ph. phosphoreum) at the no observed effect concentration (NOEC) was determined through a factorial experiment. A neural network model was designed according to experimental results and employed for toxicity prediction of unary, binary, ternary and quaternary combinations. The mechanism and trends of joint toxicity were interpreted by quantitative structure-activity relationship, Michaelis-Menten kinetic model, and concentration addition (CA) theory. Toxicity was directly related to the covalent index (Xm2r), covalent binding reaction presented a first and zero order reaction at low and high concentration, respectively, and CA accurately predicted toxicity. Additionally, the results showed that low concentrations of heavy metals should be considered when conducting environment risk assessment.

  10. Potential toxic effects of glyphosate and its commercial formulations below regulatory limits.

    Science.gov (United States)

    Mesnage, R; Defarge, N; Spiroux de Vendômois, J; Séralini, G E

    2015-10-01

    Glyphosate-based herbicides (GlyBH), including Roundup, are the most widely used pesticides worldwide. Their uses have increased exponentially since their introduction on the market. Residue levels in food or water, as well as human exposures, are escalating. We have reviewed the toxic effects of GlyBH measured below regulatory limits by evaluating the published literature and regulatory reports. We reveal a coherent body of evidence indicating that GlyBH could be toxic below the regulatory lowest observed adverse effect level for chronic toxic effects. It includes teratogenic, tumorigenic and hepatorenal effects. They could be explained by endocrine disruption and oxidative stress, causing metabolic alterations, depending on dose and exposure time. Some effects were detected in the range of the recommended acceptable daily intake. Toxic effects of commercial formulations can also be explained by GlyBH adjuvants, which have their own toxicity, but also enhance glyphosate toxicity. These challenge the assumption of safety of GlyBH at the levels at which they contaminate food and the environment, albeit these levels may fall below regulatory thresholds. Neurodevelopmental, reproductive, and transgenerational effects of GlyBH must be revisited, since a growing body of knowledge suggests the predominance of endocrine disrupting mechanisms caused by environmentally relevant levels of exposure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Effect of toxic components on microbial fuel cell-polarization curves and estimation of the type of toxic inhibition

    NARCIS (Netherlands)

    Stein, N.E.; Hamelers, H.V.M.; Straten, G. van; Keesman, K.J.

    2012-01-01

    Polarization curves are of paramount importance for the detection of toxic components in microbial fuel cell (MFC) based biosensors. In this study, polarization curves were made under non-toxic conditions and under toxic conditions after the addition of various concentrations of nickel, bentazon,

  12. Effects of Condensed Tannins on the Toxicity of Fireweed (Senecio madagascariensis) to Cattle

    OpenAIRE

    Wong, Carolyn L.

    2014-01-01

    Fireweed (Senecio madagascariensis) is a noxious and invasive weed affecting pastures in Hawaii, Australia, and South America. Fireweed contains compounds called pyrrolizidine alkaloids that are toxic to most grazing mammals. Toxic effects to cattle include irreversible damage to liver cells, hardening of the liver, and loss of liver function, which may lead to jaundice, swelling, and the accumulation of fluids in the stomach and other physiological malfunctions. External effects include roug...

  13. Synergistic effect of piperonyl butoxide on acute toxicity of pyrethrins to Hyalella azteca.

    Science.gov (United States)

    Giddings, Jeffrey; Gagne, James; Sharp, Janice

    2016-08-01

    A series of acute toxicity tests with the amphipod Hyalella azteca was performed to quantify the synergistic effect of piperonyl butoxide (PBO) on pyrethrin toxicity. Concentrations of PBO <4 µg/L caused no toxicity enhancement, whereas toxicity increased with PBO concentrations between 4 µg/L and 15 µg/L. Additive toxicity calculations showed that true synergism accounted for an increase in pyrethrin toxicity (decrease in median lethal concentration) of 1.4-fold to 1.6-fold and varied only slightly between 4 µg/L and 15 µg/L PBO, whereas direct toxicity of PBO accounted for an additional increase in mixture toxicity (up to 3.2-fold) that was proportional to PBO concentration. The results can be used to assess the risk of measured or predicted co-occurring concentrations of PBO and pyrethrins in surface waters. Environ Toxicol Chem 2016;35:2111-2116. © 2016 SETAC. © 2016 SETAC.

  14. Effects of extracts of toxic fescue given orally to rats.

    OpenAIRE

    Daniels, L B; Nelson, T S; Beasley, J. N.

    1981-01-01

    Fresh fescue (Festuca arundinacea) was obtained from farms where toxicity was encountered in cattle grazing the fescue. The fescue was dried in a forced draft oven at 60 degrees C and then ground. The dry ground fescue was extracted with ether and then re-extracted with either 1% sodium bicarbonate (NaHCO3), sodium hydroxide or hydrochloric acid. The residual ether was evaporated and the residue resuspended in ethyl alcohol diluted with water 1% (control) and 1 mL of the above extracts of fes...

  15. Sublethal gamma irradiation affects reproductive impairment and elevates antioxidant enzyme and DNA repair activities in the monogonont rotifer Brachionus koreanus

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jeonghoon; Won, Eun-Ji [Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Il-Chan; Yim, Joung Han [Division of Life Sciences, Korea Polar Research Institute, Incheon 406-840 (Korea, Republic of); Lee, Su-Jae [Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 133-791 (Korea, Republic of); Lee, Jae-Seong, E-mail: jslee2@skku.edu [Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-10-15

    Highlights: • No mortality within 96 h even at a high intensity (1200 Gy). • A reduced fecundity of Brachionus koreanus at over 150 Gy with a decrease in lifespan. • Dose-dependent ROS increase with GST enzyme activity at sub-lethal doses. • Significant impact on life table parameters, particularly fecundity. • Significant up-regulation of DNA repair-associated genes at sublethal doses. - Abstract: To examine the effects of gamma radiation on marine organisms, we irradiated several doses of gamma ray to the microzooplankton Brachionus koreanus, and measured in vivo and in vitro endpoints including the survival rate, lifespan, fecundity, population growth, gamma ray-induced oxidative stress, and modulated patterns of enzyme activities and gene expressions after DNA damage. After gamma radiation, no individuals showed any mortality within 96 h even at a high intensity (1200 Gy). However, a reduced fecundity (e.g. cumulated number of offspring) of B. koreanus at over 150 Gy was observed along with a slight decrease in lifespan. At 150 Gy and 200 Gy, the reduced fecundity of the rotifers led to a significant decrease in population growth, although in the second generation the population growth pattern was not affected even at 200 Gy when compared to the control group. At sub-lethal doses, reactive oxygen species (ROS) levels dose-dependently increased with GST enzyme activity. In addition, up-regulations of the antioxidant and chaperoning genes in response to gamma radiation were able to recover cellular damages, and life table parameters were significantly influenced, particularly with regard to fecundity. DNA repair-associated genes showed significantly up-regulated expression patterns in response to sublethal doses (150 and 200 Gy), as shown in the expression of the gamma-irradiated B. koreanus p53 gene, suggesting that these sublethal doses were not significantly fatal to B. koreanus but induced DNA damages leading to a decrease of the population size.

  16. Glioprotective Effects of Ashwagandha Leaf Extract against Lead Induced Toxicity

    Directory of Open Access Journals (Sweden)

    Praveen Kumar

    2014-01-01

    Full Text Available Withania somnifera (Ashwagandha, also known as Indian Ginseng, is a well-known Indian medicinal plant due to its antioxidative, antistress, antigenotoxic, and immunomodulatory properties. The present study was designed to assess and establish the cytoprotective potential of Ashwagandha leaf aqueous extract against lead induced toxicity. Pretreatment of C6 cells with 0.1% Ashwagandha extract showed cytoprotection against 25 μM to 400 μM concentration of lead nitrate. Further pretreatment with Ashwagandha extract to lead nitrate exposed cells (200 μM resulted in normalization of glial fibrillary acidic protein (GFAP expression as well as heat shock protein (HSP70, mortalin, and neural cell adhesion molecule (NCAM expression. Further, the cytoprotective efficacy of Ashwagandha extract was studied in vivo. Administration of Ashwagandha extract provided significant protection to lead induced altered antioxidant defense that may significantly compromise normal cellular function. Ashwagandha also provided a significant protection to lipid peroxidation (LPx levels, catalase, and superoxide dismutase (SOD but not reduced glutathione (GSH contents in brain tissue as well as peripheral organs, liver and kidney, suggesting its ability to act as a free radical scavenger protecting cells against toxic insult. These results, thus, suggest that Ashwagandha water extract may have the potential therapeutic implication against lead poisoning.

  17. Glioprotective effects of Ashwagandha leaf extract against lead induced toxicity.

    Science.gov (United States)

    Kumar, Praveen; Singh, Raghavendra; Nazmi, Arshed; Lakhanpal, Dinesh; Kataria, Hardeep; Kaur, Gurcharan

    2014-01-01

    Withania somnifera (Ashwagandha), also known as Indian Ginseng, is a well-known Indian medicinal plant due to its antioxidative, antistress, antigenotoxic, and immunomodulatory properties. The present study was designed to assess and establish the cytoprotective potential of Ashwagandha leaf aqueous extract against lead induced toxicity. Pretreatment of C6 cells with 0.1% Ashwagandha extract showed cytoprotection against 25  μM to 400 μM concentration of lead nitrate. Further pretreatment with Ashwagandha extract to lead nitrate exposed cells (200  μM) resulted in normalization of glial fibrillary acidic protein (GFAP) expression as well as heat shock protein (HSP70), mortalin, and neural cell adhesion molecule (NCAM) expression. Further, the cytoprotective efficacy of Ashwagandha extract was studied in vivo. Administration of Ashwagandha extract provided significant protection to lead induced altered antioxidant defense that may significantly compromise normal cellular function. Ashwagandha also provided a significant protection to lipid peroxidation (LPx) levels, catalase, and superoxide dismutase (SOD) but not reduced glutathione (GSH) contents in brain tissue as well as peripheral organs, liver and kidney, suggesting its ability to act as a free radical scavenger protecting cells against toxic insult. These results, thus, suggest that Ashwagandha water extract may have the potential therapeutic implication against lead poisoning.

  18. Developmental Toxic Effects of Exposure to Chemical Warfare Nerve Agents in Rats: Effects on Brain and Behavior

    Science.gov (United States)

    2015-03-01

    Yourick D (2009) Analyzing large data sets acquired through telemetry from rats exposed to organophosphorus compounds: an EEG study. J Neurosci Methods...AWARD NUMBER: W81XWH-13-2-0082 TITLE: Developmental Toxic Effects of Exposure to Chemical Warfare Nerve Agents in Rats : Effects on Brain and...2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Developmental Toxic Effects of Exposure to Chemical Warfare Nerve Agents in Rats : Effects on Brain

  19. Classification of toxicity effects of biotransformed hepatic drugs using whale optimized support vector machines.

    Science.gov (United States)

    Tharwat, Alaa; Moemen, Yasmine S; Hassanien, Aboul Ella

    2017-04-01

    Measuring toxicity is an important step in drug development. Nevertheless, the current experimental methods used to estimate the drug toxicity are expensive and time-consuming, indicating that they are not suitable for large-scale evaluation of drug toxicity in the early stage of drug development. Hence, there is a high demand to develop computational models that can predict the drug toxicity risks. In this study, we used a dataset that consists of 553 drugs that biotransformed in liver. The toxic effects were calculated for the current data, namely, mutagenic, tumorigenic, irritant and reproductive effect. Each drug is represented by 31 chemical descriptors (features). The proposed model consists of three phases. In the first phase, the most discriminative subset of features is selected using rough set-based methods to reduce the classification time while improving the classification performance. In the second phase, different sampling methods such as Random Under-Sampling, Random Over-Sampling and Synthetic Minority Oversampling Technique (SMOTE), BorderLine SMOTE and Safe Level SMOTE are used to solve the problem of imbalanced dataset. In the third phase, the Support Vector Machines (SVM) classifier is used to classify an unknown drug into toxic or non-toxic. SVM parameters such as the penalty parameter and kernel parameter have a great impact on the classification accuracy of the model. In this paper, Whale Optimization Algorithm (WOA) has been proposed to optimize the parameters of SVM, so that the classification error can be reduced. The experimental results proved that the proposed model achieved high sensitivity to all toxic effects. Overall, the high sensitivity of the WOA+SVM model indicates that it could be used for the prediction of drug toxicity in the early stage of drug development. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Toxic effects of decabromodiphenyl ether (BDE-209 on human embryonic kidney cells

    Directory of Open Access Journals (Sweden)

    Min eLi

    2014-05-01

    Full Text Available Polybrominated diphenyl ethers (PBDEs are widely used as flame-retardant additives in consumer and household products and can escape into the environment over time. PBDEs have become a global environmental organic pollutant due to the properties of persistence, toxicity, and bioaccumulation. The well-studied toxic effects of PBDEs mainly include thyroid hormone disruption and neurotoxicity. There is no consistent conclusions on the carcinogenic potential of PBDEs to date. Here, we explored the toxic effects of BDE-209 on human embryonic kidney cells (HEK293T. The comparison of the gene expression profiles of HEK293T cells with BDE-209 treatment and the negative control found that BDE-209 exposure may alter nucleosome organization through significantly changing the expression of histone gene clusters. The remodeled chromatin structure could further disturb systemic lupus erythematosus as one of the toxic effects of BDE-209. Additionally, gene sets of different cancer modules are positively correlated with BDE-209 exposure. This suggests that BDE-209 has carcinogenic potential for a variety of tumors. Collectively, BDE-209 has a broader toxicity not limited to disruption of thyroid hormone-related biological processes. Notably, the toxic effects of BDE-209 dissolved in dimethyl sulfoxide (DMSO is not the simply additive effects of BDE-209 and DMSO alone.

  1. Light induced toxicity reduction of silver nanoparticles to Tetrahymena Pyriformis: Effect of particle size

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Junpeng; Xu, Bin; Sun, Xia; Ma, Chunyan; Yu, Changping [Institute of Urban Environment, Chinese Academy of Sciences, Jimei Road 1799, Xiamen 361021 (China); Zhang, Hongwu, E-mail: hwzhang@iue.ac.cn [Institute of Urban Environment, Chinese Academy of Sciences, Jimei Road 1799, Xiamen 361021 (China)

    2013-05-15

    Highlights: ► Small AgNPs had higher toxicity than large to Tetrahymena pyriformis under dark. ► AgNPs toxicity was decreased by light. ► The decrease of small AgNP toxicity induced by light was more notable than that of large AGNPs. ► Light can influence Ag{sup +} release from, particle size of, and aggregation of AgNPs. -- Abstract: As a result of the extensive application of silver nanoparticles (AgNPs), their potential hazards, once they are released into the natural environment, are of great concern to people. Since silver is very sensitive to light, the toxicity of AgNPs released into the natural environment will be inevitably affected by light. The aim of this study was to investigate the relationship between light, toxicity, and particle size of AgNPs and deduce the possible mechanism of any interaction. Our study revealed that there was negative correlation between the particle size and the toxicity: small AgNPs (5–10 nm) had higher toxicity than large AgNPs (15–25 nm) to Tetrahymena pyriformis (T. pyriformis) under dark condition. Comparing the size dependent AgNPs toxicity under dark and light conditions, the effect of light to size dependent AgNPs toxicity was ascertained. The results indicated that AgNPs toxicity was decreased by light and the most important discovery was that the change of size dependent AgNPs toxicity had significant difference under light irradiation. The decrease of small AgNPs toxicity induced by light was more notable than large AgNPs. The decreased level of cell toxicity for small AgNPs was 32 ± 0.7%, whereas it was only 10.6 ± 5.2% for large AgNPs kept 24 h under light irradiation. The further investigation indicated that the above changes induced by light can be attributed to the decrease of released silver ions, particle growth and aggregation of AgNPs under light irradiation. The obtained results showed that the light irradiation can promote the rapid growth of small AgNPs and result in the obvious increase of

  2. Is A/A/O process effective in toxicity removal? Case study with coking wastewater.

    Science.gov (United States)

    Shi, Liu; Wang, Dong; Cao, Di; Na, Chunhong; Quan, Xie; Zhang, Ying

    2017-08-01

    The anaerobic-anoxic-oxic (A/A/O) process is the commonly used biological wastewater treatment process, especially for the coking wastewater. However, limit is known about its ability in bio-toxicity removal from wastewater. In this study, we evaluated the performance of A/A/O process in bio-toxicity removal from the coking wastewater, using two test species (i.e. crustacean (Daphnia magna) and zebra fish (Danio rerio)) in respect of acute toxicity, oxidative damage and genotoxicity. Our results showed that the acute toxicity of raw influent was reduced gradually along with A/A/O process and the effluent presented no acute toxicity to Daphnia magna (D. magna) and zebra fish. The reactive oxygen species (ROS) level in D. magna and zebra fish was promoted by the effluent from each tank of A/A/O process, showing that coking wastewater induced oxidative damage. Herein, the oxidative damage to D. magna was mitigated in the oxic tank, while the toxicity to zebra fish was reduced in the anoxic tank. The comet assays showed that genotoxicity to zebra fish was removed stepwise by A/A/O process, although the final effluent still presented genotoxicity to zebra fish. Our results indicated that the A/A/O process was efficient in acute toxicity removal, but not so effective in the removal of other toxicity (e.g. oxidative damage and genotoxicity). Considering the potential risks of wastewater discharge, further advanced toxicity mitigation technology should be applied in the conventional biological treatment process, and the toxicity index should be introduced in the regulation system of wastewater discharge. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The effect of seasonality and body size on the sensitivity of marine amphipods to toxicants.

    Science.gov (United States)

    Pérez-Landa, Víctor; Belzunce, María Jesús; Franco, Javier

    2008-12-01

    Two factors, seasonality and body size, were studied to determine their influence on the sensitivity of the amphipods Corophium urdaibaiense and Corophium multisetosum to toxicants. Seasonality was studied by comparing LC50 values for cadmium and ammonia toxicity to both species over a year. Body size effect was studied by comparing LC50 values of ammonia in three size categories of C. urdaibaiense. Except for the case of C. urdaibaiense with ammonia as a toxicant, the sensitivity was maximum during summer and minimum during winter. Furthermore, differences in sensitivities were found among the three body size groups studied.

  4. Radiolysis of selected antibiotics and their toxic effects on various aquatic organisms

    Science.gov (United States)

    Kim, Hyun Y.; Yu, Seung H.; Lee, Myun J.; Kim, Tae H.; Kim, Sang D.

    2009-04-01

    This study was conducted to investigate the decomposition of three γ-irradiated antibiotics (e.g., tetracycline, sulfamethazine, and lincomycin) and to compare the toxic effects on Daphnia magna, Vibrio fischeri, and Pseudokirchneriella subcapitata. The median cell growth inhibition concentrations (IC 50) of tetracycline, lincomycin, and sulfamethazine for P. subcapitata dramatically increased (e.g., toxicity decreased) after radiolysis. The results demonstrated that γ-radiation treatment was efficient to decompose antibiotics and thereby their toxicity on P. subcaptitata remarkably decreased due to reduced parent compounds.

  5. Radiolysis of selected antibiotics and their toxic effects on various aquatic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Y. [Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Yu, Seung H.; Lee, Myun J.; Kim, Tae H. [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk 580-185 (Korea, Republic of); Kim, Sang D. [Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of)], E-mail: sdkim@gist.ac.kr

    2009-04-15

    This study was conducted to investigate the decomposition of three {gamma}-irradiated antibiotics (e.g., tetracycline, sulfamethazine, and lincomycin) and to compare the toxic effects on Daphnia magna, Vibrio fischeri, and Pseudokirchneriella subcapitata. The median cell growth inhibition concentrations (IC{sub 50}) of tetracycline, lincomycin, and sulfamethazine for P. subcapitata dramatically increased (e.g., toxicity decreased) after radiolysis. The results demonstrated that {gamma}-radiation treatment was efficient to decompose antibiotics and thereby their toxicity on P. subcaptitata remarkably decreased due to reduced parent compounds.

  6. Altered hematological and immunological parameters in silver catfish (Rhamdia quelen) following short term exposure to sublethal concentration of glyphosate.

    Science.gov (United States)

    Kreutz, Luiz Carlos; Gil Barcellos, Leonardo José; de Faria Valle, Stella; de Oliveira Silva, Tális; Anziliero, Deniz; Davi dos Santos, Ezequiel; Pivato, Mateus; Zanatta, Rafael

    2011-01-01

    Using agrichemicals to control unwanted species has become a necessary and common worldwide practice to improve crop production. Although most currently used agrichemicals are considered relatively safe, continuous usage contributes for soil and water contamination and collateral toxic effects on aquatic species. Few studies correlated the presence of agrichemicals on fish blood cells and natural immune system. Thus, in this study, silver catfish (Rhamdia quelen) were exposed to sublethal concentrations (10% of the LC(50-96 h)) of a glyphosate based herbicide and hematological and natural immune system parameters were evaluated. Silver catfish fingerlings exposed to glyphosate for 96 h had a significant reduction on blood erythrocytes, thrombocytes, lymphocytes and total leukocytes in contrast to a significant increase in the number of immature circulating cells. The effect of glyphosate on natural immune system was evaluated after 24h or 10 days exposure by measuring the phagocytic index of coelomic cells, and lysozyme, total peroxidase, bacteria agglutination, bactericidal activity and natural complement hemolytic activity in the serum of fingerlings. A significant reduction on phagocytic index, serum bacteria agglutination and total peroxidase was observed only after 24h exposure to glyphosate. In contrast, fingerlings exposed to glyphosate for 10 days had a significant lower serum bacteria agglutination and lysozyme activity. Glyphosate had no effect on serum bactericidal and complement natural hemolytic activity after 24h or 10 days exposure. Nonetheless, the information obtained in this study indicates that glyphosate contaminated water contributes to alter blood cells parameters and to reduce the activity of natural immune components important to mediate fish resistance to infecting microorganisms. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Concentration rather than dose defines the local brain toxicity of agents that are effectively distributed by convection-enhanced delivery.

    Science.gov (United States)

    Zhang, Rong; Saito, Ryuta; Mano, Yui; Kanamori, Masayuki; Sonoda, Yukihiko; Kumabe, Toshihiro; Tominaga, Teiji

    2014-01-30

    Convection-enhanced delivery (CED) has been developed as a potentially effective drug-delivery strategy into the central nervous system. In contrast to systemic intravenous administration, local delivery achieves high concentration and prolonged retention in the local tissue, with increased chance of local toxicity, especially with toxic agents such as chemotherapeutic agents. Therefore, the factors that affect local toxicity should be extensively studied. With the assumption that concentration-oriented evaluation of toxicity is important for local CED, we evaluated the appearance of local toxicity among different agents after delivery with CED and studied if it is dose dependent or concentration dependent. Local toxicity profile of chemotherapeutic agents delivered via CED indicates BCNU was dose-dependent, whereas that of ACNU was concentration-dependent. On the other hand, local toxicity for doxorubicin, which is not distributed effectively by CED, was dose-dependent. Local toxicity for PLD, which is extensively distributed by CED, was concentration-dependent. Traditional evaluation of drug induced toxicity was dose-oriented. This is true for systemic intravascular delivery. However, with local CED, toxicity of several drugs exacerbated in concentration-dependent manner. From our study, local toxicity of drugs that are likely to distribute effectively tended to be concentration-dependent. Concentration rather than dose may be more important for the toxicity of agents that are effectively distributed by CED. Concentration-oriented evaluation of toxicity is more important for CED. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Toxicity of benthic dinoflagellates on grazing, behavior and survival of the brine shrimp Artemia salina

    Science.gov (United States)

    Neves, Raquel A. F.; Fernandes, Tainá; dos Santos, Luciano Neves; Nascimento, Silvia M.

    2017-01-01

    Harmful algae may differently affect their primary grazers, causing sub-lethal effects and/or leading to their death. The present study aim to compare the effects of three toxic benthic dinoflagellates on clearance and grazing rates, behavioral changes, and survival of Artemia salina. Feeding assays consisted in 1-h incubations of brine shrimps with the to