Assessment of hemato-biochemical parameters on exposure to low level of deltamethrin in mouse model

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Anita Tewari

2014-03-01

Full Text Available Aim: In this study, sub-acute toxicity of deltamethrin on hematological and biochemical blood parameters of male albino Swiss mice was evaluated. Materials and Methods: Generally, the maximum permissible residue level (MRL of deltamethrin for food products lies between 0.01 to 0.5 mg/kg body weight. So the mice were exposed orally with two doses of pesticide i.e. 0.1 and 0.5 mg/kg body weight. The doses were given on a daily basis for a period of 15 days and 30 days respectively. Ground nut oil was used as control treatment. Samples of blood were collected at the end of the treatment. Hepatotoxicity was evaluated by quantitative analysis of the serum enzymes alanine transaminase (ALT, aspartate transaminase (AST, alkaline phosphatase (ALKP, total bilirubin (TBIL and serum urea. Alterations of hematological parameters were analysed by total leukocyte, differential leukocyte count and hemoglobin levels. Results: Significant increase in the levels of hepatic enzymes (ALT, AST, ALKP were observed for both doses, but no considerable differences were found by histological analysis. The hematological parameters showed significant alterations for 0.5 mg/kg body weight dose which is indicated by leukocytosis, lymphocytosis and neutropenia in long duration study. Conclusions: The results indicated that even very low dose of deltamethrin can promote hematological and hepatic alterations. Thus it is imperative to do further studies on the detrimental effect of the low levels of pyrethroid commonly present in our food, which further necessitate the reduction of maximum permissible levels of residual synthetic pyrethroid levels in foods and feed.

Xenopsylla cheopis (Siphonaptera: Pulicidae susceptibility to Deltamethrin in Madagascar.

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Sebastien Boyer

Full Text Available The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae, to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%: only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down and KD90 (90% Knock-Down times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar.

Effect of deltamethrin on transmission of gamma aminobutyric acid (GABA) and thyroid hormones in adult male albino rats

International Nuclear Information System (INIS)

Abdel-kader, S.M.; Abdel-Rahman, M.

2005-01-01

The oral administration of 1/5 LD 5 0 of deltamethrin for 15 days produced an increase in GABA content and a decrease in Cl - ions concentration in all tested brain areas (cerebellum, pons + medulla oblongata, striatum, cerebral cortex, hypothalamus, midbrain and hippocampus) of adult male albino rats, almost at most time intervals. Deltamethrin also resulted in a significant decrease in serum TSH and increase in T 3 and T 4 levels in the treated rats. From the present results, it was found that deltamethrin decreased the passage of Cl - ions in the cells which might be, in part, due to a decrease of the transmission of GABA and an increase of the circulating thyroid hormones (triiodothyronine and thyroxine). Accordingly, deltamethrin may act as GABA antagonist and may act on the hypothalamus pituitary thyroid axis. In conclusion the elevation of thyroid hormones as well as the decrease in both CL - ions and GABA transmission which could be all together responsible for the impairment of motor activity, hyper excitability and seizure that occurred in rats treated with the pyrethroid insecticide deltamethrin

Toxicological profile of deltamethrin in Triatoma brasiliensis (Hemiptera: Reduviidae) in State of Ceará, Northeastern Brazil.

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Pessoa, Grasielle Caldas D'Ávila; Trevizani, Nathália Abreu Borges; Dias, Letícia Sena; Bezerra, Claudia Mendonça de; Melo, Bernardino Vaz de; Diotaiut, Liléia

2015-01-01

Triatoma brasiliensis is the species of greatest epidemiological relevance in the semi-arid region of Brazil. This species is predominantly found in domestic environments, and it has the ability to build large colonies with high levels of natural infection via Trypanosoma cruzi. Thus, T. brasiliensis is one of the most efficient transmitters of Chagas disease (CD) to humans. Despite household spraying with residual insecticides, many areas report persistent reinfestations for reasons that remain poorly understood. Therefore, this study sought to characterize the toxicological profile of deltamethrin in T. brasiliensis from areas with persistent reinfestation in State of Ceará, Brazil. The susceptibility reference lineage (SRL) was derived from Umari. Serial dilutions of deltamethrin were prepared and applied to the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed mortality in response to a diagnostic dose of 1xLD99 (0.851 nanograms of active ingredient per treated nymph) of the SRL. The susceptibility profile characterization of the T. brasiliensis populations revealed 50% resistance ratios (RR50) that ranged from 0.32 to 1.21. The percentage of mortality in response to the diagnostic dose was 100%. We demonstrated that T. brasiliensis was highly susceptible to deltamethrin. The control difficulties found might be related to the recolonization of the triatomines originating from neighboring environments and the possible operational failures related to the process of spraying that enabled specimens less susceptible to deltamethrin to survive.

Developmental Deltamethrin Exposure Causes Persistent Changes in Dopaminergic Gene Expression, Neurochemistry, and Locomotor Activity in Zebrafish.

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Kung, Tiffany S; Richardson, Jason R; Cooper, Keith R; White, Lori A

2015-08-01

Pyrethroids are commonly used insecticides that are considered to pose little risk to human health. However, there is an increasing concern that children are more susceptible to the adverse effects of pesticides. We used the zebrafish model to test the hypothesis that developmental exposure to low doses of the pyrethroid deltamethrin results in persistent alterations in dopaminergic gene expression, neurochemistry, and locomotor activity. Zebrafish embryos were treated with deltamethrin (0.25-0.50 μg/l), at concentrations below the LOAEL, during the embryonic period [3-72 h postfertilization (hpf)], after which transferred to fresh water until the larval stage (2-weeks postfertilization). Deltamethrin exposure resulted in decreased transcript levels of the D1 dopamine (DA) receptor (drd1) and increased levels of tyrosine hydroxylase at 72 hpf. The reduction in drd1 transcripts persisted to the larval stage and was associated with decreased D2 dopamine receptor transcripts. Larval fish, exposed developmentally to deltamethrin, had increased levels of homovanillic acid, a DA metabolite. Since the DA system is involved in locomotor activity, we measured the swim activity of larval fish following a transition to darkness. Developmental exposure to deltamethrin significantly increased larval swim activity which was attenuated by concomitant knockdown of the DA transporter. Acute exposure to methylphenidate, a DA transporter inhibitor, increased swim activity in control larva, while reducing swim activity in larva developmentally exposed to deltamethrin. Developmental exposure to deltamethrin causes locomotor deficits in larval zebrafish, which is likely mediated by dopaminergic dysfunction. This highlights the need to understand the persistent effects of low-dose neurotoxicant exposure during development. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Toxicological profile of deltamethrin in Triatoma brasiliensis (Hemiptera: Reduviidae in State of Ceará, Northeastern Brazil

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Grasielle Caldas D'Ávila Pessoa

2015-02-01

Full Text Available INTRODUCTION: Triatoma brasiliensis is the species of greatest epidemiological relevance in the semi-arid region of Brazil. This species is predominantly found in domestic environments, and it has the ability to build large colonies with high levels of natural infection via Trypanosoma cruzi. Thus, T. brasiliensis is one of the most efficient transmitters of Chagas disease (CD to humans. Despite household spraying with residual insecticides, many areas report persistent reinfestations for reasons that remain poorly understood. Therefore, this study sought to characterize the toxicological profile of deltamethrin in T. brasiliensis from areas with persistent reinfestation in State of Ceará, Brazil. METHODS: The susceptibility reference lineage (SRL was derived from Umari. Serial dilutions of deltamethrin were prepared and applied to the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed mortality in response to a diagnostic dose of 1xLD99 (0.851 nanograms of active ingredient per treated nymph of the SRL. RESULTS: The susceptibility profile characterization of the T. brasiliensis populations revealed 50% resistance ratios (RR50 that ranged from 0.32 to 1.21. The percentage of mortality in response to the diagnostic dose was 100%. CONCLUSIONS: We demonstrated that T. brasiliensis was highly susceptible to deltamethrin. The control difficulties found might be related to the recolonization of the triatomines originating from neighboring environments and the possible operational failures related to the process of spraying that enabled specimens less susceptible to deltamethrin to survive.

Possibility of irradiation degradation of Fenpropathrin and Deltamethrin in green tea

International Nuclear Information System (INIS)

Hu Yifang; Wan Xiaochun; Hou Ruyan; Zhang Haiwei; Zhao Xiuxia; Wang Xiaohui

2011-01-01

The effects of 60 Co γ irradiation and green tea manufacturing processing on degradation of Fenpropathrin and Deltamethrin in green tea during its manufacturing processing were studied. The two pesticides were sprayed onto the tea bushes and fresh tea leaves were picked at the same day, respectively. Half of the fresh leaves were processed into green tea. The fresh tea leaves and green tea were irradiated at 5 kGy and the Fenpropathrin in fresh tea degraded 7.3% after irradiation, while Deltamethrin degraded 14.7%. In green tea, Fenpropathrin and Deltamethrin degraded 2.2% and 12.1% respectively after irradiation. Green tea manufacturing processes could reduce 16.4% of Fenpropathrin, and 4.4% of Deltamethrin. (authors)

Distribution of multiple pesticide residues in apple segments after home processing

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Rasmussen, Rie Romme; Poulsen, Mette Erecius; Hansen, H. C. B.

2003-01-01

The effects of washing, storing, boiling, peeling, coring and juicing on pesticide residue were investigated for field-sprayed Discovery and Jonagold apples. Residues of chlorpyrifos, cypermethrin, deltamethrin, diazinon, endosulfan, endosulfan sulfate, fenitrothion, fenpropathrin, iprodione, kre...

Synergistic effect of Eugenia jambolana Linn. and Solidago canadensis Linn. leaf extracts with deltamethrin against the dengue vector Aedes aegypti Linn. at Mysore.

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Raghavendra, B S; Prathibha, K P; Vijayan, V A

2013-06-01

With the goal in mind to minimize the application of environmentally hazardous chemical insecticides, the larvicidal activity of two plant extracts along with deltamethrin was studied at University of Mysore. The extracts of Solidago canadensis and Eugenia jambolana were employed for working out the synergistic efficacy against Aedes aegypti larvae, as the extracts of both the plants exhibited high efficacy when applied individually. The deltamethrin when analyzed separately, LC50 and LC90 values were 0.00045 and 0.00148 ppm, respectively. Synergistic studies with two plant extracts on deltamethrin revealed S. canadensis as more effective with synergistic factor(SF) of 4.090 for LC50 value and 4.781 for LC90 followed by E. jambolana with SF 1.80 for LC50 and 2.467 for LC90 at 1:1 ratio of the phytoextracts and deltamethrin. Thus, S. canadensis was found to be a better larvicidal and synergistic agent. Combination of phytochemical and insecticide were found to be more effective than insecticides or phytochemicals alone which could be a good ecofriendly and cost-effective approach to reduce the dose of chemicals with high residual effect to be applied in vector control programs.

Impact of Acute Deltamethrin Poisoning on Rat Adrenal Glands: Biochemical and Pathomorphological Study

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Eugene A. Chigrinski

2017-09-01

Full Text Available Background: Deltamethrin is known all over the world as an effective preparation for the control of insects. In connection with this, its role as a chemical stressor increases. The aim of the study was to determine the features of the functioning and structure of AG after a single administration of synthetic pyrethroid deltamethrin in experimental animals at a dose of 17.4 mg/kg (1/5 LD50. Material and Methods: For the experiment, 88 male Wistar rats with a body weight of 240±10 g were divided into 8 groups of 10–12 animals each. Groups 1, 3, 5, and 7 were control groups, which were administered physiological solution intragastrically. The animals in Groups 2, 4, 6, and 8 received a single dose (17.4mg/kg of deltamethrin, which corresponds to 1/5 LD50. In the serum of rats, the content of ACTH, progesterone, DHEA-sulfate, corticosterone and aldosterone was determined by EIA. Histological preparations of adrenal glands were stained with H&E, picrofuxin according to Van Gieson, and with Bismarck brown according to Shubich. On frozen sections, lipids were detected by Sudan Black B.\tResults: One day after intoxication, we identified an increase in adrenal mass, edema of the parenchyma and blood capillary overflow, and a large number of lipids in corticocytes. In the blood serum, the concentration of ACTH and corticosteroids increased, but their level decreased in the adrenal cortex. After 3 days, the concentration of corticosterone in the blood serum of the experimental animals remained above the control value, but the content of other hormones decreased. At the border of the cortex and the medulla of the adrenal glands, there were mast cells in a state of degranulation; the amount of lipids decreased with time. In the subsequent terms of the study, a decrease in the weight of AG with a decrease in the concentration of hormones in the blood serum and adrenal tissue was detected. Conclusion: The intoxication of rats with deltamethrin causes

Could humic acid relieve the biochemical toxicities and DNA damage caused by nickel and deltamethrin in earthworms (Eisenia foetida)?

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Shen, Chen-Chao; Shen, Dong-Sheng; Shentu, Jia-Li; Wang, Mei-Zhen; Wan, Ming-Yang

2015-12-01

The aim of the study was to determine whether humic acid (HA) prevented gene and biochemical toxic effects in earthworms (Eisenia foetida) exposed to nickel and deltamethrin (at 100 and 1 mg kg(-1), respectively) in soil. Cellular- and molecular-level toxic effects of nickel and deltamethrin in earthworms were evaluated by measuring damage to lipid membranes and DNA and the production of protein carbonyls over 42 days of exposure. Nickel and deltamethrin induced significant levels of oxidative stress in earthworms, increasing the production of peroxidation products (malondialdehyde and protein carbonyls) and increasing the comet assay tail DNA% (determined by single-cell gel electrophoresis). DNA damage was the most sensitive of the three indices because it gave a higher sample/control ratio than did the other indices. The presence of HA alleviated (in decreasing order of effectiveness) damage to DNA, proteins, and lipid membranes caused by nickel and deltamethrin. A low HA dose (0.5-1% HA in soil) prevented a great deal of lipid membrane damage, but the highest HA dose (3% HA in soil) prevented still more DNA damage. However, the malondialdehyde concentrations in earthworms were higher at the highest HA dose than at the lower HA doses. The amounts of protein carbonyls produced at different HA doses were not significantly different. The toxic effects to earthworms caused by increased oxidizable nickel concentrations could be relieved by adding HA.

Divergent actions of the pyrethroid insecticides S-bioallethrin, tefluthrin, and deltamethrin on rat Nav1.6 sodium channels

International Nuclear Information System (INIS)

Tan Jianguo; Soderlund, David M.

2010-01-01

We expressed rat Na v 1.6 sodium channels in combination with the rat β 1 and β 2 auxiliary subunits in Xenopus laevis oocytes and evaluated the effects of the pyrethroid insecticides S-bioallethrin, deltamethrin, and tefluthrin on expressed sodium currents using the two-electrode voltage clamp technique. S-Bioallethrin, a type I structure, produced transient modification evident in the induction of rapidly decaying sodium tail currents, weak resting modification (5.7% modification at 100 μM), and no further enhancement of modification upon repetitive activation by high-frequency trains of depolarizing pulses. By contrast deltamethrin, a type II structure, produced sodium tail currents that were ∼ 9-fold more persistent than those caused by S-bioallethrin, barely detectable resting modification (2.5% modification at 100 μM), and 3.7-fold enhancement of modification upon repetitive activation. Tefluthrin, a type I structure with high mammalian toxicity, exhibited properties intermediate between S-bioallethrin and deltamethrin: intermediate tail current decay kinetics, much greater resting modification (14.1% at 100 μM), and 2.8-fold enhancement of resting modification upon repetitive activation. Comparison of concentration-effect data showed that repetitive depolarization increased the potency of tefluthrin ∼ 15-fold and that tefluthrin was ∼ 10-fold more potent than deltamethrin as a use-dependent modifier of Na v 1.6 sodium channels. Concentration-effect data from parallel experiments with the rat Na v 1.2 sodium channel coexpressed with the rat β 1 and β 2 subunits in oocytes showed that the Na v 1.6 isoform was at least 15-fold more sensitive to tefluthrin and deltamethrin than the Na v 1.2 isoform. These results implicate sodium channels containing the Na v 1.6 isoform as potential targets for the central neurotoxic effects of pyrethroids.

Detoxification enzymes activities in deltamethrin and bendiocarb ...

African Journals Online (AJOL)

Detoxification enzymes activities in deltamethrin and bendiocarb resistant and susceptible malarial vectors ( Anopheles gambiae ) breeding in Bichi agricultural and residential sites, Kano state, Nigeria.

Photodegradation of bifenthrin and deltamethrin-effect of copper amendment and solvent system.

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Tariq, Saadia Rashid; Ahmed, Dildar; Farooq, Amna; Rasheed, Sonia; Mansoor, Mubarkah

2017-02-01

The photodegradation of bifenthrin and deltamethrin was studied in the presence of Cu salts and two different solvents, methanol and acetonitrile. Results of the study showed that in the absence of any metal salt, the two pesticides degraded more rapidly in acetonitrile than in methanol. After 24 h of UV irradiation, 70% of deltamethrin had degraded in acetonitrile, while only 41% bifenthrin degraded in this solvent. In methanol, bifenthrin degraded at a much enhanced rate than in acetonitrile while the rate of degradation of deltamethrin was comparable to that in acetonitrile. The photodegradation was further enhanced by the addition of copper to the solution of bifenthrin and deltamethrin in acetonitrile. The rate of photodegradation of deltamethrin increased from 2.4 × 10 -2 to 3.5 × 10 -2  h -1 in acetonitrile and 2.5 × 10 -2 to 3.4 × 10 -2  h -1 in methanol after the addition of copper. Similarly, the rate of photodegradation of bifenthrin was increased from 5.0 × 10 -3 to 9.0 × 10 -3  h -1 in acetonitrile and 7.0 × 10 -3 to 9.05 × 10 -3  h -1 in methanol with the addition of copper. Thus, copper has the potential to enhance the photodegradation of bifenthrin and deltamethrin in both the solvents.

The effect of deltamethrin-treated net fencing around cattle enclosures on outdoor-biting mosquitoes in Kumasi, Ghana.

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Marta Ferreira Maia

Full Text Available Classic vector control strategies target mosquitoes indoors as the main transmitters of malaria are indoor-biting and -resting mosquitoes. However, the intensive use of insecticide-treated bed-nets (ITNs and indoor residual spraying have put selective pressure on mosquitoes to adapt in order to obtain human blood meals. Thus, early-evening and outdoor vector activity is becoming an increasing concern. This study assessed the effect of a deltamethrin-treated net (100 mg/m(2 attached to a one-meter high fence around outdoor cattle enclosures on the number of mosquitoes landing on humans. Mosquitoes were collected from four cattle enclosures: Pen A - with cattle and no net; B - with cattle and protected by an untreated net; C - with cattle and protected by a deltamethrin-treated net; D - no cattle and no net. A total of 3217 culicines and 1017 anophelines were collected, of which 388 were Anopheles gambiae and 629 An. ziemanni. In the absence of cattle nearly 3 times more An. gambiae (p<0.0001 landed on humans. The deltamethrin-treated net significantly reduced (nearly three-fold, p<0.0001 culicine landings inside enclosures. The sporozoite rate of the zoophilic An. ziemanni, known to be a secondary malaria vector, was as high as that of the most competent vector An. gambiae; raising the potential of zoophilic species as secondary malaria vectors. After deployment of the ITNs a deltamethrin persistence of 9 months was observed despite exposure to African weather conditions. The outdoor use of ITNs resulted in a significant reduction of host-seeking culicines inside enclosures. Further studies investigating the effectiveness and spatial repellence of ITNs around other outdoor sites, such as bars and cooking areas, as well as their direct effect on vector-borne disease transmission are needed to evaluate its potential as an appropriate outdoor vector control tool for rural Africa.

Ocimum basilicum essential oil combined with deltamethrin to improve the management of Spodoptera frugiperda

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Sérgio Macedo Silva

Full Text Available ABSTRACT For an important and expensive crop such as corn, the resistance of Spodoptera frugiperda J.E. Smith to various pesticides has led to research throughout the world for a potential insecticide from a natural source. For the management of pest resistance, natural compounds associated with synthetic insecticides can be a promising tool because they can reduce the application of the synthetics molecules while maintaining their effectiveness and promoting the control of the pests. Linalool is a potential insecticide that is easily obtained because it is found in high concentrations in the essential oil of Ocimum basilicum L. Therefore, the present study aimed to evaluate the toxicity of this essential oil and its combination with deltamethrin to control S. frugiperda. Through dose response assays, the acute toxicities (LD50 of the essential oil and deltamethrin were estimated. Additionally, the combination of these materials was also assessed, attaining a reduction of 80% of the LD50 of deltamethrin while obtaining the same result as when the pyrethroid was administered alone. From these results, it is expected that the combination of natural compounds and synthetic insecticides will be a promising practice, helping to manage resistance while reducing the environmental impact of toxic compounds.

Study On The Procedures For Determining Of Pesticide Residues In Green Vegetables

International Nuclear Information System (INIS)

Le Tat Mua; Nguyen Tien Dat; Nguyen Van Minh; Nguyen Ngoc Tuan; Le Thi Ngoc Trinh; Ta Thi Tuyet Nhung; Truong Van Tai; Tran Thanh Nha; Nguyen Thi Hong Tham

2007-01-01

Researches presented in this work are divided into two main parts. One part embraces the residue analytical methods. The other part comprises applying of these residue analytical methods for analysis of plant material. Part I: Residue analytical methods (Analytical procedures): Determination of Endosulphan in plant material by GC/ECD; Determination of Methamidofos in plant material by GC/FTD; Determination of Deltamethrin, Cyhalothrin, Cyfluthrin in plant material by GC/ECD; Determination of Maneb in plant material by HPLC/UV; Determination of Zineb in plant material by F-AAS; Determination of Organo-Asenic and Mercury in plant material by RNAA; The limits of detection and determination (LOD, LOQ), Recovery, Efficiency, the Calibration curve are validated. Part II: Applying of Residue Analytical Methods for analysis of endosulphan, methamidofos, maneb, zineb, cyhalothrin, deltamethrin, cyfluthrin, metallo-organic compounds in Spinach, Cabbage, Pimento, Japanese Bean, Japanese Pumpkin, Tomato, Potato, Sweet Potato. The results and conclusion are present in this work. (author)

Differential state-dependent modification of rat Na{sub v}1.6 sodium channels expressed in human embryonic kidney (HEK293) cells by the pyrethroid insecticides tefluthrin and deltamethrin

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He, Bingjun [College of Life Sciences, Nankai University, Tianjin 300071 (China); Soderlund, David M., E-mail: dms6@cornell.edu [Department of Entomology, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456 (United States)

2011-12-15

We expressed rat Na{sub v}1.6 sodium channels in combination with the rat {beta}1 and {beta}2 auxiliary subunits in human embryonic kidney (HEK293) cells and evaluated the effects of the pyrethroid insecticides tefluthrin and deltamethrin on expressed sodium currents using the whole-cell patch clamp technique. Both pyrethroids produced concentration-dependent, resting modification of Na{sub v}1.6 channels, prolonging the kinetics of channel inactivation and deactivation to produce persistent 'late' currents during depolarization and tail currents following repolarization. Both pyrethroids also produced concentration dependent hyperpolarizing shifts in the voltage dependence of channel activation and steady-state inactivation. Maximal shifts in activation, determined from the voltage dependence of the pyrethroid-induced late and tail currents, were {approx} 25 mV for tefluthrin and {approx} 20 mV for deltamethrin. The highest attainable concentrations of these compounds also caused shifts of {approx} 5-10 mV in the voltage dependence of steady-state inactivation. In addition to their effects on the voltage dependence of inactivation, both compounds caused concentration-dependent increases in the fraction of sodium current that was resistant to inactivation following strong depolarizing prepulses. We assessed the use-dependent effects of tefluthrin and deltamethrin on Na{sub v}1.6 channels by determining the effect of trains of 1 to 100 5-ms depolarizing prepulses at frequencies of 20 or 66.7 Hz on the extent of channel modification. Repetitive depolarization at either frequency increased modification by deltamethrin by {approx} 2.3-fold but had no effect on modification by tefluthrin. Tefluthrin and deltamethrin were equally potent as modifiers of Na{sub v}1.6 channels in HEK293 cells using the conditions producing maximal modification as the basis for comparison. These findings show that the actions of tefluthrin and deltamethrin of Na{sub v}1.6 channels

Deltamethrin-induced testicular apoptosis in rats: the protective effect of nitric oxide synthase inhibitor.

Science.gov (United States)

El-Gohary, M; Awara, W M; Nassar, S; Hawas, S

1999-01-01

This study is the first to examine and characterize the testicular apoptosis which might be induced due to exposure of male rats to deltamethrin. Furthermore, the role which might be played by nitric oxide (NO), as well as the other reactive oxygen species (ROS) in controlling this testicular apoptosis was assessed. Apoptosis was evaluated by DNA fragmentation detected by agarose gel electrophoresis and cellular morphology on testicular tissue sections. It was found that administration of deltamethrin (1 mg/kg daily for 21 days) to animals resulted in characteristic DNA migration patterns (laddering), thereby providing evidence that apoptosis is the major mechanism of cell death in the testicular tissues. In addition, histopathological examination of testicular tissue sections showed that apoptosis was confined to the basal germ cells, primary and secondary spermatocytes. These changes, in addition to the appearance of Sertoli cell vacuoles in deltamethrin-intoxicated animals, indicates the suppression of spermatogenesis. At the same time, the plasma levels of both NO and lipid peroxides measured as malondialdehyde (MDA) were found to be significantly increased in deltamethrin-treated animals. Administration of NO synthase (NOS) inhibitors such as N(G)-nitro monomethyl L-arginine hydrochloride (L-NMMA, 1 mg/kg) to rats 2 h before exposure to deltamethrin was effective in the reduction of the typically testicular apoptotic DNA fragmentation pattern and the associated histopathological changes. These findings may suggest that deltamethrin-induced testicular apoptosis is mediated by NO. Therefore, the pharmacological manipulation of apoptosis by selective NOS inhibitors such as L-NMMA may offer new possibilities for the control of deltamethrin-induced testicular dysfunction and infertility in the future.

Determination of pesticide residue levels in omani and UAE vegetable farm soils

International Nuclear Information System (INIS)

Talukder, F.A.; Dahmani, J.H.A.; Kaakeh, W.; Deadman, M.L.

2008-01-01

In the investigation of 40 different vegetable growing farms of Al-Batinah (Oman) and Al - Ain (UAE) regions different pesticide residues were found to be present on all soil samples which varied in their types and levels according to the region. In Omani soil samples, cypermethrin was the most frequent pesticide, followed by chlorpyrifos, malathion, phenthoate, triazophos and deltamethrin. In UAE farm soil samples, chlorpyrifos, cypermethrin and deltamethrin were detected in all the regions, while phenthoate was detected in the Eastern and Northern regions only. (author)

Studies on the environmental chemistry and dissipation of 14C-labelled Deltamethrin and Amitraz in model dips

International Nuclear Information System (INIS)

Musumeci, M.R.; Coelho, P.V.; Luchini, L.C.

1997-01-01

The degradation of 14 C-labelled deltamethrin under variable conditions of pH and temperature, leaching of 14 C-labelled amitraz in soil columns and dissipation of these insecticides in model dipping vat was studied. Deltamethrin was stable for 28 d in buffer solutions at pH 4,7 and 8 and at temperature of 14, 28 and 35 deg. C, but degraded in a solution at pH 9. Metabolites identified by TLC corresponded to 3-phenoxybenzoic acid and 3-phenoxybenzyl alcohol. After 75 days of standing in a model dip, about 60% of the total radioactivity was found in the sediment and corresponded mainly to deltamethrin. When 14 C-Amitraz was applied to soil columns, placed under outdoor conditions, 4 months later all of the radiocarbon was found in the upper 10 cm section and about 90% of the recovered radioactivity corresponded with amitraz. A study of the dissipation of amitraz in a field vat showed that after 20 d of use the concentration of amitraz in a field dip decreased from 210 μg/mL to 155 μg/mL. (author)

Effects of Carbaryl and Deltamethrin Pesticides on Some Pituitary Hormones of Male Albino Rats

International Nuclear Information System (INIS)

Abdel-Kader, S.M.; Ezz El-Arab, A.; Aly, M.A.S.

2005-01-01

This investigation aims to study the effects of oral administrations of 1/10 LD 5 0 of both carbaryl and deltamethrin pesticides on some pituitary hormones of male rats namely; adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH), growth hormone (GH), beta-endorphin (b-end) and prolactin hormone (prol). At different time intervals of 1,3,7 and 10 days, blood samples were collected and sera were separated and analyzed for hormonal assessment using RIA technique. The data clarified that daily oral administrations of 1/10 LD 5 0 of both carbaryl (28.6 mg/kg body weight) and deltamethrin (12.8 mg/kg body weight) to male albino rats resulted in gradual and significant decreases in serum ACTH recording 70.60% and 71.75% as compared to control on the 1 0 ''th day of carbaryl and deltamethrin treatments, respectively. Similarly, serum TSH and GH levels were significantly decreased one day after treatment showing their maximum decreases on the 1 0t h day recording 30.09% and 40.25% for TSH and 43.84% and 41.47% for GH after treatment with carbaryl and deltamethrin, respectively. Moreover, serum b-endorphin level showed maximum and significant decreases of 29.47% and 33.28% on day 10 of treatment with carbaryl and deltamethrin, respectively. On the other hand, serum prolactin level was significantly increased one day after treatment showing its maximum increase at the end of the experimental period recording 92.06% and 84.52% for carbaryl and deltamethrin, respectively. From the present data, it could be suggested that the pituitary gland is a major target for the two pesticides carbaryl and deltamethrin which have the potential to influence the modulation of endocrine system via the hypothalamus pituitary axis

DDT-based indoor residual spraying suboptimal for visceral leishmaniasis elimination in India.

Science.gov (United States)

Coleman, Michael; Foster, Geraldine M; Deb, Rinki; Pratap Singh, Rudra; Ismail, Hanafy M; Shivam, Pushkar; Ghosh, Ayan Kumar; Dunkley, Sophie; Kumar, Vijay; Coleman, Marlize; Hemingway, Janet; Paine, Mark J I; Das, Pradeep

2015-07-14

Indoor residual spraying (IRS) is used to control visceral leishmaniasis (VL) in India, but it is poorly quality assured. Quality assurance was performed in eight VL endemic districts in Bihar State, India, in 2014. Residual dichlorodiphenyltrichloroethane (DDT) was sampled from walls using Bostik tape discs, and DDT concentrations [grams of active ingredient per square meter (g ai/m(2))] were determined using HPLC. Pre-IRS surveys were performed in three districts, and post-IRS surveys were performed in eight districts. A 20% threshold above and below the target spray of 1.0 g ai/m(2) was defined as "in range." The entomological assessments were made in four districts in IRS and non-IRS villages. Vector densities were measured: pre-IRS and 1 and 3 mo post-IRS. Insecticide susceptibility to 4% DDT and 0.05% deltamethrin WHO-impregnated papers was determined with wild-caught sand flies. The majority (329 of 360, 91.3%) of pre-IRS samples had residual DDT concentrations of DDT post-IRS was 0.37 g ai/m(2); 84.9% of walls were undersprayed, 7.4% were sprayed in range, and 7.6% were oversprayed. The abundance of sand flies in IRS and non-IRS villages was significantly different at 1 mo post-IRS only. Sand flies were highly resistant to DDT but susceptible to deltamethrin. The Stockholm Convention, ratified by India in 2006, calls for the complete phasing out of DDT as soon as practical, with limited use in the interim where no viable IRS alternatives exist. Given the poor quality of the DDT-based IRS, ready availability of pyrethroids, and susceptibility profile of Indian sand flies, the continued use of DDT in this IRS program is questionable.

Toxicity of several contact insecticides to Tribolium castaneum (Herbst populations after selection with pirimiphos-methyl and deltamethrin

Directory of Open Access Journals (Sweden)

Goran Andrić

2015-12-01

Full Text Available Laboratory bioassays were conducted to detect possible alteration in susceptibility of two field Tribolium castaneum (Herbst populations (sampled in a warehouse in Nikinci and a silo in Jakovo to dichlorvos, malathion, chlorpyrifos-methyl, pirimiphos-methyl, deltamethrin and bifenthrin after previous selection with the LD80 of pirimiphos-methyl and deltamethrin. Data from the topical application bioassays show that chlorpyrifos-methyl was the most toxic insecticide to T. castaneum adults of the Nikinci population selected with pirimiphosmethyl and deltamethrin, while malathion was the weakest, and both selection procedures changed/reduced significantly only the toxicity of deltamethrin and bifenthrin, increasing their resistance ratios (RR at the LD50 from 1.1 to 1.8 (bifenthrin and from 0.9 to 2.2 (deltamethrin. Deltamethrin was the most toxic insecticide for Jakovo adults selected with the LD80 of pirimiphosmethyl, while malathion was again the least toxic. Selection of that population had no effect on insecticide toxicity, except of malathion, which had a rise in RR at the LD50 from 26.0 to 29.8.

40 CFR 180.435 - Deltamethrin; tolerances for residues.

Science.gov (United States)

2010-07-01

... in food handling establishments, including food service, manufacturing and processing establishments.... Contamination of food/feed or food/feed contact surfaces shall be avoided. (B) To assure safe use of the...) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances...

Multistep bioassay to predict recolonization potential of emerging parasitoids after a pesticide treatment.

Science.gov (United States)

Desneux, Nicolas; Ramirez-Romero, Ricardo; Kaiser, Laure

2006-10-01

Neurotoxic pyrethroid insecticides are widely used for crop protection, and lethal and sublethal perturbations can be expected in beneficial insects. Under laboratory conditions, the lethal and sublethal effects of deltamethrin on the aphid parasitoid Diaeretiella rapae M'Intosh (Hymenoptera: Braconidae) were studied at the mummy stage and in emerging adults. Following a multistep bioassay, analyses were aimed at evaluating the effects of deltamethrin at various crucial steps in the recolonization process following a deltamethrin treatment: Parasitoid pupal development (emergence from the mummies), adult survival, and host-searching capacity. A four-armed olfactometer was used to investigate the effect of deltamethrin on host-searching behavior (a range of concentrations causing 0.4-79.4% mortality was tested), and a Potter tower was used to test the deltamethrin effect with a realistic application method (four concentrations were tested: 0.5, 5.0, 6.25, and 50 g active ingredient [a.i.]/ha). Deltamethrin reduced the percentage of emergence from mummies, but only when exposed to the 50 g a.i./ha concentration. However, for all concentrations tested, the insecticide induced a decrease in longevity after emergence from sprayed mummies and significant adult mortality when parasitoids walked on fresh residues on leaves. Indices were defined and predicted a high mortality and, thus, reduction of recolonization capacities. However, deltamethrin had no effect on orientation behavior toward aphid-infested plants for adults that survived a residual exposure to the insecticide. The impact of deltamethrin on recolonization via pupal emergence and interest in the methodology used are discussed.

Efficacy of granular deltamethrin against Ixodes scapularis and Amblyomma americanum (Acari: Ixodidade) nymphs.

Science.gov (United States)

Schulze, T L; Jordan, R A; Hung, R W; Taylor, R C; Markowski, D; Chomsky, M S

2001-03-01

A single barrier application of granular deltamethrin to the woodland edges of a forested residential community in late spring significantly reduced the abundance of Ixodes scapularis Say nymphs. The application also suppressed the population of Amblyomma americanum (L.) nymphs, which recently became established in the study area. The efficacy of deltamethrin is compared with other commonly used acaricides.

Effects of abamectin and deltamethrin to the foragers honeybee workers of Apis mellifera jemenatica (Hymenoptera: Apidae under laboratory conditions

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Dalal Musleh Aljedani

2017-07-01

Full Text Available This study aimed at evaluating the toxicity of some insecticides (abamectin and deltamethrin on the lethal time (LT50 and midgut of foragers honeybee workers of Apis mellifera jemenatica were studied under laboratory conditions. The bees were provided with water, food, natural protein and sugar solution with insecticide (concentration: 2.50 ppm deltamethrin and 0.1 ppm abamectin. The control group was not treated with any kind of insecticides. The mortality was assessed at 1, 2, 4, 6, 12, 24, 48, and 72 hour (h after insecticides treatment and period to calculate the value of lethal time (LT50. But the samples the histology study of midgut collected after 24 h were conducted by Scanning Electron Microscope. The results showed the effects of insecticides on the current results show that abamectin has an adverse effect on honeybees, there is a clear impact on the lethal time (LT50 was the abamectin faster in the death of honeybee workers compared to deltamethrin. Where have reached to abamectin (LT50 = 21.026 h, deltamethrin (LT50 = 72.011 h. However, abamectin also effects on cytotoxic midgut cells that may cause digestive disorders in the midgut, epithelial tissue is formed during morphological alterations when digestive cells die. The extends into the internal cavity, and at the top, there is epithelial cell striated border that has many holes and curves, abamectin seems to have crushed the layers of muscle. Through the current results can say abamectin most toxicity on honeybees colony health and vitality, especially foragers honeybee workers.

Assessing the effect of selection with deltamethrin on biological parameters and detoxifying enzymes in Aedes aegypti (L.).

Science.gov (United States)

Alvarez-Gonzalez, Leslie C; Briceño, Arelis; Ponce-Garcia, Gustavo; Villanueva-Segura, O Karina; Davila-Barboza, Jesus A; Lopez-Monroy, Beatriz; Gutierrez-Rodriguez, Selene M; Contreras-Perera, Yamili; Rodriguez-Sanchez, Iram P; Flores, Adriana E

2017-11-01

Resistance to insecticides through one or several mechanisms has a cost for an insect in various parameters of its biological cycle. The present study evaluated the effect of deltamethrin on detoxifying enzymes and biological parameters in a population of Aedes aegypti selected for 15 generations. The enzyme activities of alpha- and beta-esterases, mixed-function oxidases and glutathione-S-transferases were determined during selection, along with biological parameters. Overexpression of mixed-function oxidases as a mechanism of metabolic resistance to deltamethrin was found. There were decreases in percentages of eggs hatching, pupation and age-specific survival and in total survival at the end of the selection (F 16 ). Although age-specific fecundity was not affected by selection with deltamethrin, total fertility, together with lower survival, significantly affected gross reproduction rate, gradually decreasing due to deltamethrin selection. Similarly, net reproductive rate and intrinsic growth rate were affected by selection. Alterations in life parameters could be due to the accumulation of noxious effects or deleterious genes related to detoxifying enzymes, specifically those coding for mixed-function oxidases, along with the presence of recessive alleles of the V1016I and F1534C mutations, associating deltamethrin resistance with fitness cost in Ae. aegypti. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Analysis of deltamethrin's degradation products by irradiation

International Nuclear Information System (INIS)

Wu Ling; Huang Min; Chen Chun; Lei Qing; Du Xiaoying; Xie Yan; Wang Yan; Gao Peng; He Jiang

2012-01-01

Deltamethrin were dissolved in ethanol and water; acetone and water; dimethylsulfoxide and water, irradiating these liquors by 60 Co-γ under the dose of 5∼50 kGy. The irradiation system were analyzed by GC/MS, result shows: there were some differences under different irradiation doses; the main degradation products are: α-cyano-3-phenoxy benzyl alcohol, 3-Phenoxybenzaldehyde, 3-Phenoxybenzacetonitrile and bromomethane. (authors)

Sub-acute deltamethrin and fluoride toxicity induced hepatic oxidative stress and biochemical alterations in rats.

Science.gov (United States)

Dubey, Nitin; Khan, Adil Mehraj; Raina, Rajinder

2013-09-01

The current study investigated the effects of deltamethrin, fluoride (F(-)) and their combination on the hepatic oxidative stress and consequent alterations in blood biochemical markers of hepatic damage in rats. Significant hepatic oxidative stress and hepatic damage were observed in the toxicant exposed groups. These changes were higher in the deltamethrin-F(-) co-exposure treatment group, depicting a positive interaction between the two chemicals.

Pesticide residues in nut-planted soils of China and their relationship between nut/soil.

Science.gov (United States)

Han, Yongxiang; Mo, Runhong; Yuan, Xinyue; Zhong, Donglian; Tang, Fubin; Ye, Caifen; Liu, Yihua

2017-08-01

Twenty-nine pesticide residues in nut-planted soils from China were investigated. One organophosphate (chlorpyrifos) was detected in 5.3% soils, and the residue levels of 7.2 μg/kg to 77.2 μg/kg. The concentrations of six organochlorines (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) detected in 78.9% soils were 0.6 μg/kg to 90.1 μg/kg. The residue levels of six pyrethroids (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) detected in 65.8% soils were 1.5 μg/kg to 884.3 μg/kg. Triadimefon and buprofezin were found in 71.1% and 52.6% samples, respectively, with the corresponding concentrations of 9.8 μg/kg to 193.7 μg/kg and 87.9 μg/kg to 807.4 μg/kg. The multiple residues were found in 76.3% soils. A significant correlation between pesticide residues in nuts and soils was observed, with the correlation coefficient (r) 0.83 (P < 0.001). In addition, the bioconcentration factor (BCF) values for the explanation of pesticides from soils into nuts were ranged from 0.8 to 16.5. The results showed that some pesticides could accumulate in nut by the uptake effect from soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative metabolism of the pyrethroids bifenthrin and deltamethrin in the bulb mite Rhizoglyphus robini

International Nuclear Information System (INIS)

Ruzo, L.O.; Cohen, E.; Capua, S.

1988-01-01

The fate of 14 C-radiolabeled bifenthrin and deltamethrin was studied in the mite, Rhizoglyphus robini. Administered either by ingestion or by contact, both pyrethroids were efficiently metabolized, but deltamethrin was degraded to a much greater extent. The identified metabolites arise from a combination of ester cleavage, oxidation, and conjugation reactions. With 14 C-acid- and 14 C-alcohol-labeled bifenthrin, the free metabolites detected were the 4'-hydroxy derivative of the ester, the primary ester cleavage products, the acid, and its 4'-hydroxy derivative from the alcohol moiety, as well as several unidentified metabolites. Using 14 C-alcohol-labeled deltamethrin, 3-phenoxybenzoic acid and its 4'-hydroxylated product and several unknown metabolites were detected. Conjugates comprised the bulk of total pyrethroid metabolites. In addition to ester cleavage products, the 4'-hydroxylated bifenthrin was also identified. For the first time in invertebrates, a conjugated pyrethroid ester was observed

Evaluation of pesticide residues in fruits and vegetables from Algeria.

Science.gov (United States)

Mebdoua, Samira; Lazali, Mohamed; Ounane, Sidi Mohamed; Tellah, Sihem; Nabi, Fahima; Ounane, Ghania

2017-06-01

A total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and import were analysed to detect the presence of pesticide residues. Analysis was performed by multi-residual extraction followed by gas chromatography-mass spectrometry. In 42.5% of the tested samples, no residues were found and 12.5% of samples contained pesticide residues above maximum residue limits. Risk assessment for long-term exposure was done for all pesticides detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment revealed that in seven pesticide/commodity combinations, including three pesticides (chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded.

The effect of insecticide Deltamethrin on development of chick embryos

International Nuclear Information System (INIS)

Al-Naal, R.; Bassal, M. Osman, M.

1997-04-01

This study was conducted to evaluate the cyto and the embryo toxicity of Deltamethrin and its commercial formulation DECIS 50 EC in chick embryo during its critical embryonic development period before and in the organogenesis. The embryos were incubated in well closed plastic caps containing the complete egg composition at 38 o. the Deltamethrin and DECIS were found to cause histological and morphological malformations, specially in the brain, also they reduced the majority of the synthetic activities of the DNA, RNA, and proteins in the embryonic and the vascular areas. The flow cytometric analysis showed alterations in frequency of cells in both embryonic and vascular areas in the treated embryo during the cell cycle phases. Our study also showed that the DECIS had greater cyto and embryo toxicity than the Seltamethrin for analysis (author). 149 refs., 36 figs., 16 tabs

Comparative metabolism of the pyrethroids bifenthrin and deltamethrin in the bulb mite Rhizoglyphus robini

Energy Technology Data Exchange (ETDEWEB)

Ruzo, L.O.; Cohen, E.; Capua, S. (The Hebrew Univ. of Jerusalem (Israel))

The fate of {sup 14}C-radiolabeled bifenthrin and deltamethrin was studied in the mite, Rhizoglyphus robini. Administered either by ingestion or by contact, both pyrethroids were efficiently metabolized, but deltamethrin was degraded to a much greater extent. The identified metabolites arise from a combination of ester cleavage, oxidation, and conjugation reactions. With {sup 14}C-acid- and {sup 14}C-alcohol-labeled bifenthrin, the free metabolites detected were the 4{prime}-hydroxy derivative of the ester, the primary ester cleavage products, the acid, and its 4{prime}-hydroxy derivative from the alcohol moiety, as well as several unidentified metabolites. Using {sup 14}C-alcohol-labeled deltamethrin, 3-phenoxybenzoic acid and its 4{prime}-hydroxylated product and several unknown metabolites were detected. Conjugates comprised the bulk of total pyrethroid metabolites. In addition to ester cleavage products, the 4{prime}-hydroxylated bifenthrin was also identified. For the first time in invertebrates, a conjugated pyrethroid ester was observed.

Determination of pesticide residues in fruits of Nawabshah district, Sindh, Pakistan

International Nuclear Information System (INIS)

Anwar, T.; Ahmad, I.; Tahir, S.

2011-01-01

Eight fruit samples of apple, guava, orange, grapes, pear, persimmon, banana and pear purchased from the local markets of Nawabshah district, Sindh and residues of pesticide of organophosphate (OP), pyrethroid and organochlorine (OC) (i.e., dichlorvos, fenvalerate, dimethoate, methyl parathion, fenitrothion, cypermethrin, endosulfan, deltamethrin, mevinphos, chlorpyriphos, profenofos and dicofol) were monitored in fruit samples by Gas Chromatography (GC). All the fruit samples were found contaminated except banana and among these only apple samples were found exceeding the maximum residue limits (MRL) of Codex Alimentarius Commission. (author)

Effects of the pyrethroid insecticide, deltamethrin, on respiratory modulated hypoglossal motoneurons in a brain stem slice from newborn mice

DEFF Research Database (Denmark)

Rekling, J C; Theophilidis, G

1995-01-01

We have studied the action of deltamethrin on respiratory modulated hypoglossal motoneurons in a brain stem slice from newborn mice. Deltamethrin depolarized the hypoglossal motoneurons, increased the background synaptic noise and reduced the frequency and amplitude of current elicited action...

Dual control of ticks and tsetse flies using deltamethrin through ...

African Journals Online (AJOL)

Dual control of ticks and tsetse flies using deltamethrin through community participatory methods. M Ocaido, C P Otim, N M Okuna, C Ssekitto, D Kakaire, J Erume, R Z O Wafula, J Walubengo, G Musisi, Okello Bwangamoi, S Okure, W Ebiaru, G Monrad ...

Assessment of the Efficacy of Deltamethrin Impregnated Bed Nets ...

African Journals Online (AJOL)

The impact of deltamethrin treated bednets and walls were assessed on school children aged 12-18 years, in a community secondary school in Ono, Nigeria. Children with body weights of 45-60kg were given 2 tablets of fansidar to clear parasites in their system while those with body weights of 60kg and above were given ...

Analysing deltamethrin susceptibility and pyrethroid esterase activity variations in sylvatic and domestic Triatoma infestans at the embryonic stage

Directory of Open Access Journals (Sweden)

Pablo Luis Santo-Orihuela

2013-12-01

Full Text Available The aim of the present work was to study the deltamethrin susceptibility of eggs from Triatoma infestans populations and the contribution of pyrethroid esterases to deltamethrin degradation. Insects were collected from sylvatic areas, including Veinte de Octubre and Kirus-Mayu (Bolivia and from domiciliary areas, including El Palmar (Bolivia and La Pista (Argentina. Deltamethrin susceptibility was determined by dose-response bioassays. Serial dilutions of deltamethrin (0.0005-1 mg/mL were topically applied to 12-day-old eggs. Samples from El Palmar had the highest lethal dose ratio (LDR value (44.90 compared to the susceptible reference strain (NFS, whereas the Veinte de Octubre samples had the lowest value (0.50. Pyrethroid esterases were evaluated using 7-coumaryl permethrate (7-CP on individually homogenised eggs from each population and from NFS. The El Palmar and La Pista samples contained 40.11 and 36.64 pmol/min/mg protein, respectively, and these values were statistically similar to NFS (34.92 pmol/min/mg protein and different from Kirus-Mayu and Veinte de Octubre (27.49 and 22.69 pmol/min/mg protein, respectively. The toxicological data indicate that the domestic populations were resistant to deltamethrin, but no statistical contribution of 7-CP esterases was observed. The sylvatic populations had similar LDR values to NFS, but lower 7-CP esterase activities. Moreover, this is the first study of the pyrethroid esterases on T. infestans eggs employing a specific substrate (7-CP.

In vitro and in vivo studies of Allium sativum extract against deltamethrin-induced oxidative stress in rats brain and kidney.

Science.gov (United States)

Ncir, Marwa; Saoudi, Mongi; Sellami, Hanen; Rahmouni, Fatma; Lahyani, Amina; Makni Ayadi, Fatma; El Feki, Abdelfattah; Allagui, Mohamed Salah

2017-09-18

The present study investigated the in vitro and the in vivo antioxidant capacities of Allium sativum (garlic) extract against deltamethrin-induced oxidative damage in rat's brain and kidney. The in vitro result showed that highest extraction yield was achieved with methanol (20.08%). Among the tested extracts, the methanol extract exhibited the highest total phenolic, flavonoids contents and antioxidant activity. The in vivo results showed that deltamethrin treatment caused an increase of the acetylcholinesterase level (AChE) in brain and plasma, the brain and kidney conjugated dienes and lipid peroxidation (LPO) levels as compared to control group. The antioxidant enzymes results showed that deltamethrin treatment induced a significantly decrease (p < 0.01) in brain and kidney antioxidant enzymes as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) to control group. The co-administration of garlic extract reduced the toxic effects in brain and kidney tissues induced by deltamethrin.

Variability of pesticide residues in cauliflower units collected from a field trial and market places in Greece.

Science.gov (United States)

Prodhan, M D H; Papadakis, Emmanouil-N; Papadopoulou-Mourkidou, Euphemia

2016-09-01

To estimate the variability of pesticide residue levels present in cauliflower units, a total of 142 samples were collected from a field trial of a cooperative farmer, and 120 samples were collected from different market places in Thessaloniki, Greece. The collected samples were extracted using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction technique, and the residues were determined by liquid chromatography-tandem mass spectrometry. The developed method was validated by evaluating the accuracy, precision, linearity, limit of detection (LOD), and limit of quantification (LOQ). The average recoveries for all the analytes, derived from the data of control samples fortified at 0.01, 0.05, 0.1, and 0.2 mg/kg, ranged from 74 to 110% with a relative standard deviation of ≤8%. The correlation coefficient (R(2)) was ≥0.997 for all the analytes using matrix-matched calibration standards. The LOD values ranged from 0.001 to 0.003 mg/kg, and the LOQ was determined at 0.01 mg/kg for all the sought analytes. The matrix effect was found to be at a considerable level, especially for cypermethrin and deltamethrin, amounting to +90% and +145%, respectively. For the field samples, the unit-to-unit variability factors (VFs) calculated for cypermethrin and deltamethrin were 2.38 and 2.32, respectively, while the average VF for the market basket samples was 5.11. In the market basket samples, residues of cypermethrin, deltamethrin, chlorpyrifos, and indoxacarb were found at levels ≥LOQ and their respective VFs were 7.12, 5.67, 5.28, and 2.40.

Analysis of deltamethrin's degradation products by irradiation

International Nuclear Information System (INIS)

Wu Ling; Huang Min; Chen Chun; Lei Qing; Du Xiaoying; Xie Yan; Wang Yan; Gao Peng; He Jiang

2011-01-01

Deltamethrin were dissolved in ethanol and water; acetone and water; dimethylsulfoxide and water, irradiating these liquors by 60 Co-γ under the dose of 5∼50 kGy. The irradiation system were analyzed by GC/MS, result shows: there were some differences under different irradiation doses; the main degradation products are: α-cyano-3-phenoxy benzyl alcohol, 3-Phenoxybenzaldehyde, 3-Phenoxybenzacetonitrile and bromomethane. (authors)

Histopathological, oxidative damage, biochemical, and genotoxicity alterations in hepatic rats exposed to deltamethrin: modulatory effects of garlic (Allium sativum).

Science.gov (United States)

Ncir, Marwa; Ben Salah, Ghada; Kamoun, Hassen; Makni Ayadi, Fatma; Khabir, Abdelmajid; El Feki, Abdelfattah; Saoudi, Mongi

2016-06-01

Deltamethrin is a pesticide widely used as a synthetic pyrethroid. The aim of this study was undertaken to investigate the effects of deltamethrin to induce oxidative stress and changes in biochemical parameters, hepatotoxicity and genotoxicity in female rats following a short-term (30 days) oral exposure and attenuation of these effects by Allium sativum extract. Indeed, Allium sativum is known to be a good antioxidant food resource which helps destroy free radical particles. Our results showed that deltamethrin treatment caused an increase in liver enzyme activities of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH); and hepatic lipid peroxidation (LPO) level. However, it induced a decrease in activities of hepatic catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) (p Allium sativum extract normalized significantly (p Allium sativum diminished the adverse effects induced by this synthetic pyrethroid insecticide.

Insecticide residues in stored grains in Sonora, Mexico: quantification and toxicity testing.

Science.gov (United States)

Aldana-Madrid, M L; Valdez-Hurtado, S; Vargas-Valdez, N D; Salazar-Lopez, N J; Silveira-Gramont, M I; Loarca-Piña, F G; Rodríguez-Olibarria, G; Wong-Corral, F J; Borboa-Flores, J; Burgos-Hernández, A

2008-02-01

Food safety has acquired great attention by food importer and exporters. Food rejection or acceptance across international borders is based on the compliance with international food regulations. Due to the lack of recent data on pesticide residues in Mexican grains, this study focused on detecting and quantifying insecticide residues in stored wheat, corn, chickpeas, and beans, as well as to determine their mutagenic potential. Grains were sampled from primary storage sites in Sonora, Mexico. Malathion, chlorpyrifos, deltamethrin, cypermethrin, 4,4-DDE, 4,4-DDD and 4,4-DDT were analyzed in 135 samples. Grain samples were not mutagenic and most pesticide levels were within regulation limits.

Deltamethrin-resistant German Cockroaches Are Less Sensitive to the Insect Repellents DEET and IR3535 than Non-resistant Individuals.

Science.gov (United States)

Mengoni, Sofía L; Alzogaray, Raúl A

2018-04-02

The German cockroach, Blattella germanica (L.) (Blattodea: Blattellidae), is a serious worldwide pest with a considerable economical and sanitary impact. It is mainly controlled by the application of synthetic insecticides, but repeated use of these substances has promoted the appearance of resistance in cockroach populations throughout the world. The aim of this study was to compare the behavior of deltamethrin-susceptible (CIPEIN colony) and deltamethrin-resistant (JUBA and VGBA colonies) first instar nymphs exposed to the repellents N,N-diethyl-3-methylbenzamide (DEET) and ethyl 3-[acetyl(butyl)amino]propanoate (IR3535). Firstly, the behavior of the nymphs was assessed in an experimental arena in the absence of repellents. The parameters Distance Traveled, Velocity, Mobility Time, and Time Spent (in each half of the arena) were quantified using an image analyser, and showed that the behavior elicited by the three colonies was similar. After this, the behavior of the nymphs was quantified in an arena, half of which had been treated with repellent. The repellency of DEET increased as a linear function of log concentration for the three colonies. DEET elicited repellency as from a concentration of 97.49 µg/cm2 for the CIPEIN and JUBA colonies and 194.98 µg/cm2 for the VGBA colony. The repellency of IR3535 was weaker and started at a concentration of 389.96 µg/cm2 for the CIPEIN colony, 779.92 μg/cm2 for JUBA, and 1559.84 μg/cm2 for VGBA . Finally, nymphs were exposed to 3:1, 1:1, and 1:3 DEET:IR3535 mixtures, and a synergistic effect was observed only in the CIPEIN colony.

Inductions of reproduction and population growth in the generalist predator Cyrtorhinus lividipennis (Hemiptera: Miridae) exposed to sub-lethal concentrations of insecticides.

Science.gov (United States)

Lu, Weiwei; Xu, Qiujing; Zhu, Jun; Liu, Chen; Ge, Linquan; Yang, Guoqing; Liu, Fang

2017-08-01

The miridbug, Cyrtorhinus lividipennis, is a significant predacious enemy of rice planthoppers. The effects of sub-lethal concentrations of triazophos, deltamethrin and imidacloprid on fecundity, egg hatchability, expression levels of genes associated with reproduction, and population growth in C. lividipennis were investigated. The fecundities for three pair combinations (♀ c × ♂ t , ♀ t × ♂ c and ♀ t × ♂ t ) treated with sub-lethal concentrations of the insecticides triazophos, deltamethrin and imidacloprid (LC 10 and LC 20 ) showed a significant increase compared to the untreated pairs (♀ c × ♂ c ). However, sub-lethal concentration treatments did not affect the egg hatchability. The ClVg expression levels of female adults exposed to triazophos, deltamethrin and imidacloprid (LC 20 ) increased by 52.6, 48.9 and 91.2%, respectively. The ClSPATA13 expression level of adult males exposed to triazophos, deltamethrim and imidacloprid (LC 20 ) increased by 80.7, 41.3 and 48.3%, respectively. Furthermore, sub-lethal concentrations of insecticides (LC 20 ) caused increased population numbers in C. lividipennis. Sub-lethal concentrations of triazophos, deltamethrin and imidacloprid stimulated reproduction and enhanced population growth of C. lividipennis. The reproductive stimulation might result from the up-regulation of ClVg or ClSPATA13. These findings may be useful in mediating populations of planthoppers. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Effect of Residue Nitrogen Concentration and Time Duration on Carbon Mineralization Rate of Alfalfa Residues in Regions with Different Climatic Conditions

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saeid shafiei

2017-08-01

Full Text Available Introduction Various factors like climatic conditions, vegetation, soil properties, topography, time, plant residue quality and crop management strategies affect the decomposition rate of organic carbon (OC and its residence time in soil. Plant residue management concerns nutrients recycling, carbon recycling in ecosystems and the increasing CO2 concentration in the atmosphere. Plant residue decomposition is a fundamental process in recycling of organic matter and elements in most ecosystems. Soil management, particularly plant residue management, changes soil organic matter both qualitatively and quantitatively. Soil respiration and carbon loss are affected by soil temperature, soil moisture, air temperature, solar radiation and precipitation. In natural agro-ecosystems, residue contains different concentrations of nitrogen. It is important to understand the rate and processes involved in plant residue decomposition, as these residues continue to be added to the soil under different weather conditions, especially in arid and semi-arid climates. Material and methods Organic carbon mineralization of alfalfa residue with different nitrogen concentrations was assessed in different climatic conditions using split-plot experiments over time and the effects of climate was determined using composite analysis. The climatic conditions were classified as warm-arid (Jiroft, temperate arid (Narab and cold semi-arid (Sardouiyeh using cluster analysis and the nitrogen (N concentrations of alfalfa residue were low, medium and high. The alfalfa residue incubated for four different time periods (2, 4, 6 and 8 months. The dynamics of organic carbon in different regions measured using litter bags (20×10 cm containing 20 g alfalfa residue of 2-10 mm length which were placed on the soil surface. Results and discussion The results of this study showed that in a warm-arid (Jiroft, carbon loss and the carbon decomposition rate constant were low in a cold semi

Effects of deltamethrin treated uniform on malaria prophylaxis in troops of Bahawalpur garrison

International Nuclear Information System (INIS)

Younis, M.; Murtaza, G.; Nasir

2017-01-01

Objective: To determine the efficacy of deltamethrin treated uniforms on repellant action against mosquitos in serving soldiers. Study Design: Randomized control trial. Place and Duration of Study: Bahawalpur Garrison, from 18 Aug to 24 Aug 2014. Patient and Methods: Two groups were selected for the study, one group comprising of 100 x soldiers wearing deltamethrin treated uniforms and other group comprising 100 x soldiers wearing non-treated (normal working) uniforms-control group. All soldiers were males, their age ranged from 20 years to 41 year. Uniforms were issued centrally with no group knowing which group has been issued treated uniforms, (double blind study was carried out to eliminate subject bias). Coding system was evolved while issuing the uniforms which were only known to the main researchers, president of the study board. Both the groups were made to sit for one hour in a large training ground of the formation in two separate groups at a distance of 50-60 feet between the groups and 10-15 feet between the individuals. All the individuals were asked to count the number of mosquitos attracted towards them, whether sitting/biting on their uniforms or on their bodies. Mosquito counting was also facilitated by the organizing/conducting staff. The study continued for a week from 18-24 Aug 2014. All soldiers were given 2 x tabs Chloroquine stat as prophylaxis for malaria prior to the study. Mean and SD of no of bites of both groups were compared and analyzed. Student t-test was applied to note the statistical significance among the study groups. Results: Out of the two groups the individuals wearing deltamethrin treated uniforms showed about overall 90 percent protection from mosquitos as compared to the control group. The average number of bites by mosquitoes in the control group was 7/person in one hour, whereas it was less than one bite/person in the case group. Conclusion: This study confirmed that the deltamethrin treated uniform is highly effective in

Pengaruh insektisida deltametrin terhadap perilaku orientasi parasitoid Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae

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Araz Meilin

2016-09-01

Full Text Available Host searching behaviour by a parasitoid includes orientation to the volatile compounds (odor relesead by host or host plant. The aim of this study was to determine the changes in the orientation behaviour of Anagrus nilaparvatae (Pang et Wang, the egg parasitoid of rice brown planthoppers (Nilaparvata lugens (Stål, after being exposed to sublethal concentrations of deltamethrin. The impact of residue on plants to the behaviour of parasitoid was also studied. The sublethal concentrations (LC10 and LC40 used were 0.023 ppm and 2.235 ppm, respectively. Deltamethrin applied to the rice plants were 12.5 ppm and 6.25 ppm, and its effect was observed at 3 hours, 1, 3 and 7 days after application. Orientation behavior was studied using Y-tube olfactometer. Application of deltamethrin at subletal concentration reduced the ability of surviving A. nilaparvatae to detect odors (volatile ompounds released by the host, N. lugens. The higher the concentration of deltamethrin applied to the parasitoid or to the rice plants, the more prominent effect observed in the changing in the parasitoid behavious, in particular disruption to the parasitoid’s orientation to find their host. As consequences, effects of deltamethrin may lead to reduce the effectiveness of A. nilaparvatae as biological control agents in the field as a result of declining their searching capacity. 

Determination of potassium concentration in salt water for residual beta radioactivity measurements

International Nuclear Information System (INIS)

Suarez-Navarro, J.A.; Pujol, Ll.

2004-01-01

High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method

Regional specificity in deltamethrin induced cytochrome P450 expression in rat brain

International Nuclear Information System (INIS)

Yadav, Sanjay; Johri, Ashu; Dhawan, Alok; Seth, Prahlad K.; Parmar, Devendra

2006-01-01

Oral administration of deltamethrin (5 mg/kg x 7 or 15 or 21 days) was found to produce a time-dependent increase in the mRNA expression of xenobiotic metabolizing cytochrome P450 1A1 (CYP1A1), 1A2 and CYP2B1, 2B2 isoenzymes in rat brain. RT-PCR studies further showed that increase in the mRNA expression of these CYP isoenzymes observed after 21 days of exposure was region specific. Hippocampus exhibited maximum increase in the mRNA expression of CYP1A1, which was followed by pons-medulla, cerebellum and hypothalamus. The mRNA expression of CYP2B1 also exhibited maximum increase in the hypothalamus and hippocampus followed by almost similar increase in midbrain and cerebellum. In contrast, mRNA expression of CYP1A2 and CYP2B2, the constitutive isoenzymes exhibited relatively higher increase in pons-medulla, cerebellum and frontal cortex. Immunoblotting studies carried out with polyclonal antibody raised against rat liver CYP1A1/1A2 or CYP2B1/2B2 isoenzymes also showed increase in immunoreactivity comigrating with CYP1A1/1A2 or 2B1/2B2 in the microsomal fractions isolated from hippocampus, hypothalamus and cerebellum of rat treated with deltamethrin. Though the exact relationship of the xenobiotic metabolizing CYPs with the physiological function of the brain is yet to be clearly understood, the increase in the mRNA expression of the CYPs in the brain regions that regulate specific brain functions affected by deltamethrin have further indicated that modulation of these CYPs could be associated with the various endogenous functions of the brain

Susceptibility to deltamethrin of wild and domestic populations of Triatoma infestans of the Gran Chaco and the Inter-Andean Valleys of Bolivia.

Science.gov (United States)

Gomez, Marinely Bustamante; D'Avila, Grasielle Caldas Pessoa; Orellana, Ana Lineth Garcia; Cortez, Mirko Rojas; Rosa, Aline Cristine Luiz; Noireau, François; Diotaiuti, Liléia Gonçalves

2014-11-14

The persistence of Triatoma infestans and the continuous transmission of Trypanosoma cruzi in the Inter-Andean Valleys and in the Gran Chaco of Bolivia are of great significance. Coincidentally, it is in these regions the reach of the vector control strategies is limited, and reports of T. infestans resistance to insecticides, including in wild populations, have been issued. This study aims to characterize the susceptibility to deltamethrin of wild and domestic populations of T. infestans from Bolivia, in order to better understand the extent of this relevant problem. Susceptibility to deltamethrin was assessed in nine, wild and domestic, populations of T. infestans from the Gran Chaco and the Inter-Andean Valleys of Bolivia. Serial dilutions of deltamethrin in acetone (0.2 μL) were topically applied in first instar nymphs (F1, five days old, fasting, weight 1.2 ± 0.2 mg). Dose response results were analyzed with PROBIT version 2, determining the lethal doses, slope and resistance ratios (RR). Qualitative tests were also performed. Three wild T. infestans dark morph samples of Chaco from the Santa Cruz Department were susceptible to deltamethrin with RR50 of Bolivia are less susceptible.

Temperature influences the toxicity of deltamethrin, chlorpyrifos and dimethoate to the predatory mite Hypoaspis aculeifer (Acari) and the springtail Folsomia candida (Collembola).

Science.gov (United States)

Jegede, O O; Owojori, O J; Römbke, J

2017-06-01

In order to assess the influence of temperature on pesticide toxicity to soil fauna, specimens of the predatory mite Hypoaspis aculeifer and the springtail Folsomia candida were exposed in artificial soil spiked with different concentrations of three pesticides (dimethoate, chlorpyrifos and deltamethrin) at 20°C vs 28°C for the mites and 20°C vs 26°C for the springtails. All tests were carried out according to OECD guidelines. In the mite tests, the toxic effects of dimethoate and chlorpyrifos on survival was about two orders of magnitude more at 28°C than at 20°C. Mite reproduction decreased in the tests with chlorpyrifos and deltamethrin by about four to five orders of magnitude at 28°C than at 20°C. (EC50 28 ° C =1.42 and 2.52mg/kg vs EC50 20 ° C =6.18 and 10.09mg/kg) In the collembolan tests, the toxicity of dimethoate on survival was higher at 26°C than at 20°C (LC50 26 ° C =0.17mg/kg vs LC50 20 ° C =0.36mg/kg), while the opposite was detected for deltamethrin (LC50 26 ° C =11.27mg/kg vs LC50 20 ° C =6.84mg/kg). No difference was found in the test with chlorpyrifos. Effects of dimethoate and chlorpyrifos on reproduction were higher at 26°C than at 20°C (EC50 26 ° C =0.11 and 0.018mg/kg vs EC50 20 ° C =0.29 and 0.031mg/kg respectively), but in the case of deltamethrin the opposite was observed (EC50 26 ° C =12.85mg/kg vs EC50 20 ° C =2.77mg/kg). A preliminary risk assessment of the three pesticides at the two temperature regimes based on the Toxicity Exposure Ratio (TER) approach of the European Union, shows that in general there are few different outcomes when comparing data gained at different temperatures. However, in the light of the few comparisons made data gained in temperate regions should be used with caution in the tropics. Copyright © 2017 Elsevier Inc. All rights reserved.

Residual effect of a micro-encapsulated formulation of organophosphates and piriproxifen on the mortality of deltamethrin resistant Triatoma infestans populations in rural houses of the Bolivian Chaco region

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Abraham Gemio Alarico

2010-09-01

Full Text Available The Bolivian Chaco is part of the endemic region of Chagas disease and an area where pyrethroid resistant Triatoma infestans (Hemiptera: Reduviidae populations has been reported. The World Health Organization identified these resistant populations as an important focus for research. The objective of this study was to evaluate the residual effect of a micro-encapsulated formulation containing organophosphate active ingredients and a juvenile hormone analogue (Inesfly 5A IGR on the mortality of T. infestans. Studies took place in rural houses of the Bolivian Chaco that were treated up to 34 months before and evaluated the susceptibility to pyrethroids of the offspring of field collected insects. Thirty houses were randomly selected within three communities to carry out wall bio-assays with T. infestans nymphs. Mortality was recorded 24, 48 and 72 h after wall contact. Eggs laid by females collected in the area were used to obtain first-instar nymphs and carry out pyrethroid susceptibility tests. The wall bio-assays showed that the micro-encapsulated insecticide eliminates T. infestans populations and produces detectable mortality of insects exposed to walls treated 34 months prior to the tests. The discriminant dose of deltamethrin (0.01 mg/mL showed 65% nymph survival, whereas at the highest tested dose (1.0 mg/mL 14% of the nymphs survived. These results show that Inesfly 5A IGR is an appropriate tool for the elimination of intradomestic and peridomestic populations of T. infestans resistant to pyrethroids.

Biogas from Agricultural Residues as Energy Source in Hybrid Concentrated Solar Power

NARCIS (Netherlands)

Corré, W.J.; Conijn, J.G.

2016-01-01

This paper explores the possibilities of sustainable biogas use for hybridisation of Concentrated Solar Power (HCSP) in Europe. The optimal system for the use of biogas from agricultural residues (manure and crop residues) in HCSP involves anaerobic digestion with upgrading of biogas to

Residual pyrethroids in fresh horticultural products in Sonora, Mexico.

Science.gov (United States)

Aldana-Madrid, Maria L; Valenzuela-Quintanar, Ana I; Silveira-Gramont, Maria I; Rodríguez-Olibarría, Guillermo; Grajeda-Cota, Patricia; Zuno-Floriano, Fabiola G; Miller, Marion G

2011-10-01

This study was conducted to evaluate the presence of cyhialothrin, cyfluthrin, cypermethrin, fenvalerate, and deltamethrin in vegetables produced and consumed in Sonora, Mexico. A total of 345 samples were collected from cluster sampling of markets and fields. Approximately 9% of the samples tested positive for pyrethroids (residue range 0.004-0.573 mg kg(-1)). Based on the results, the potential toxicological risk of human exposure to the pyrethroid insecticides measured in vegetables appears to be minimal, with the estimated exposure being 1,000 times lower than admissible levels. © Springer Science+Business Media, LLC 2011

Virgin olive oil ameliorates deltamethrin-induced nephrotoxicity in mice: A biochemical and immunohistochemical assessment

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Ali Reza khalatbary

Full Text Available Objective: A major class of synthetic pyrethroid insecticide, deltamethrin (DM, can elicit pathophysiological effects through oxidative stress in non-targeted organisms such as mammals. There is accumulating evidence that virgin olive oil (VOO, a rich source of polyphenolic components, have anti-oxidant, anti-inflammatory, and anti-apoptotic properties. This study aimed to determine the protective and ameliorative effects of VOO against DM-induced nephrotoxicity. Methods & materials: Mice were randomly divided into four equal groups: DM group, DM plus VOO group, VOO group, and vehicle group. Five weeks after gavaging, kidney samples were taken for biochemical assessment of malondialdehyde (MDA, glutathione (GSH and catalase (CAT, and for immunohistochemical assessment of caspase-3, cyclooxygenase-2 (cox-2 and poly (ADP-ribose polymerase (PARP. Results: The MDA level in kidney was increased in the DM group, which was significantly decreased after VOO administration in the DM plus VOO group. The GSH level and CAT activiy in kidney were decreased in the DM group, which were significantly increased after VOO administration in the DM plus VOO group. Greater expression of caspase-3, cox-2, and PARP could be detected in the DM group, which was significantly attenuated in the DM plus VOO group. Also, the histopathological changes which were detected in the DM group attenuated after VOO consumption. Conclusion: Virgin olive oil exerted protective effects against deltamethrin-induced nephrotoxicity, which might be associated with its anti-apoptotic, anti-inflammatory, and anti-oxidative properties. Keywords: Deltamethrin, Virgin olive oil, Antioxidant, Apoptosis, Inflammation, Nephrotoxicity

Changes in Plasma Corticosterone and Catecholamine Contents Induced by Low Doses of Deltamethrin in Rats

NARCIS (Netherlands)

Boer, Sietse F. de; Gugten, Jan van der; Slangen, Jef. L.; Hijzen, Theo H.

1988-01-01

The effects of low doses of (S)-α-cyano-3-phenoxybenzyl (1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate (Roussel UCLAF, Paris, France), (deltamethrin) upon sympathetic-adrenomedullary and pituitary-adrenocortical activity were investigated in rats by measuring plasma noradrenaline

Can fractal methods applied to video tracking detect the effects of deltamethrin pesticide or mercury on the locomotion behavior of shrimps?

Science.gov (United States)

Tenorio, Bruno Mendes; da Silva Filho, Eurípedes Alves; Neiva, Gentileza Santos Martins; da Silva, Valdemiro Amaro; Tenorio, Fernanda das Chagas Angelo Mendes; da Silva, Themis de Jesus; Silva, Emerson Carlos Soares E; Nogueira, Romildo de Albuquerque

2017-08-01

Shrimps can accumulate environmental toxicants and suffer behavioral changes. However, methods to quantitatively detect changes in the behavior of these shrimps are still needed. The present study aims to verify whether mathematical and fractal methods applied to video tracking can adequately describe changes in the locomotion behavior of shrimps exposed to low concentrations of toxic chemicals, such as 0.15µgL -1 deltamethrin pesticide or 10µgL -1 mercuric chloride. Results showed no change after 1min, 4, 24, and 48h of treatment. However, after 72 and 96h of treatment, both the linear methods describing the track length, mean speed, mean distance from the current to the previous track point, as well as the non-linear methods of fractal dimension (box counting or information entropy) and multifractal analysis were able to detect changes in the locomotion behavior of shrimps exposed to deltamethrin. Analysis of angular parameters of the track points vectors and lacunarity were not sensitive to those changes. None of the methods showed adverse effects to mercury exposure. These mathematical and fractal methods applicable to software represent low cost useful tools in the toxicological analyses of shrimps for quality of food, water and biomonitoring of ecosystems. Copyright © 2017 Elsevier Inc. All rights reserved.

Kemampuan Beberapa Jamur Tanah Dalam Menguraikan Pestisida Deltametrin Dan Senyawa Lignoselulosa [the Ability of Some Soil Fungi on Degradation of Deltamethrin and Lignocelluloses

OpenAIRE

Subowo, YB

2013-01-01

Some of soil fungi capable in degrading pesticide deltamethrin, therefore they can be used as fertilizer in organic farming. As a biofertilizer ,fungus also must be able to provide nutrients for plants. The purpose of the study was to obtain fungal isolates that have the ability to decompose pesticides deltamethrin and lignocellulose compounds, dissolved inorganic phosphate compounds and produce growth hormone IAA (Indole Acetic Acid) . The fungal isolates will then be used in the manufacture...

Age, Dose, and Time-Dependency of Plasma and Tissue Distribution of Deltamethrine in Immature Rats

Science.gov (United States)

The major objective of this project was to characterize the systemic disposition of the pyrethroid, deltamethrin (DLT), in immature rats, with emphasis on the age-dependence of target organ (brain) dosimetry. Postnatal day (PND) 10, 21, and 40 male Sprague-Dawley rats received 0...

Potential dermal exposure to deltamethrin and risk assessment for manual sprayers: Influence of crop type

Energy Technology Data Exchange (ETDEWEB)

Hughes, Enrique A.; Flores, Andrea P.; Ramos, Laura M.; Zalts, Anita [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, B1613GSX Los Polvorines, Prov. de Buenos Aires (Argentina); Richard Glass, C. [Department for Environment, Food and Rural Affairs, Central Science Laboratory, Sand Hutton, York Y041 1LZ (United Kingdom); Montserrat, Javier M. [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, B1613GSX Los Polvorines, Prov. de Buenos Aires (Argentina); Instituto de Investigaciones en Ingenieria Genetica y Biologia Molecular (CONICET), Vuelta de Obligado 2490, 2o piso, Buenos Aires (Argentina)], E-mail: jmontser@ungs.edu.ar

2008-02-25

A comparison of the Potential Dermal Exposure (PDE) of workers to the insecticide deltamethrin was made as a function of crop type, in small agricultural production units in Argentina. Seven experiments were done with two different crops (maize and broccoli, treated area between 600 and 1000 m{sup 2}) with three different operators under typical field conditions using a lever operated knapsack. The methodology is based on the whole body dosimetry technique, presenting separately the data for mixing/loading and application activities. These results indicate a higher concentration of pesticide in lower body sections for broccoli and a wider distribution for maize. The risk inherent in these agricultural procedures is estimated through Margin of Safety (MOS) values and was found to be generally safe. Preliminary results of a mass balance distribution of the pesticide between crop, soil and operator are also presented.

Potential dermal exposure to deltamethrin and risk assessment for manual sprayers: Influence of crop type

International Nuclear Information System (INIS)

Hughes, Enrique A.; Flores, Andrea P.; Ramos, Laura M.; Zalts, Anita; Richard Glass, C.; Montserrat, Javier M.

2008-01-01

A comparison of the Potential Dermal Exposure (PDE) of workers to the insecticide deltamethrin was made as a function of crop type, in small agricultural production units in Argentina. Seven experiments were done with two different crops (maize and broccoli, treated area between 600 and 1000 m 2 ) with three different operators under typical field conditions using a lever operated knapsack. The methodology is based on the whole body dosimetry technique, presenting separately the data for mixing/loading and application activities. These results indicate a higher concentration of pesticide in lower body sections for broccoli and a wider distribution for maize. The risk inherent in these agricultural procedures is estimated through Margin of Safety (MOS) values and was found to be generally safe. Preliminary results of a mass balance distribution of the pesticide between crop, soil and operator are also presented

Study on the pelletizing of sulfate residue with magnetite concentrate in grate-kiln system

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Shufeng Y.

2010-01-01

Full Text Available The experiment on the feasibility of pelletizing with magnetite concentrate and the wasted sulfate residue was carried out, to research the performance of pellet in grate-kiln system and simulate the grate-kiln pelletizing process in the micro-pellet roasting simulation system in laboratory, and the process experiments on preheating and roasting sections were conducted. The results show that in order to obtain pellet with good performance and the magnetite concentrate should be over 20 in mass percent, the suitable pelletizing time is about 10 min and moisture is around 12.5%. Also, according to the process parameters of drying and preheating sections obtained from experiment, it will be successful to use magnetite concentrate and the wasted sulfate residue for pelletizing, which exploits a new way for the use of sulfate residue.

Uncertainty of pesticide residue concentration determined from ordinary and weighted linear regression curve.

Science.gov (United States)

Yolci Omeroglu, Perihan; Ambrus, Árpad; Boyacioglu, Dilek

2018-03-28

Determination of pesticide residues is based on calibration curves constructed for each batch of analysis. Calibration standard solutions are prepared from a known amount of reference material at different concentration levels covering the concentration range of the analyte in the analysed samples. In the scope of this study, the applicability of both ordinary linear and weighted linear regression (OLR and WLR) for pesticide residue analysis was investigated. We used 782 multipoint calibration curves obtained for 72 different analytical batches with high-pressure liquid chromatography equipped with an ultraviolet detector, and gas chromatography with electron capture, nitrogen phosphorus or mass spectrophotometer detectors. Quality criteria of the linear curves including regression coefficient, standard deviation of relative residuals and deviation of back calculated concentrations were calculated both for WLR and OLR methods. Moreover, the relative uncertainty of the predicted analyte concentration was estimated for both methods. It was concluded that calibration curve based on WLR complies with all the quality criteria set by international guidelines compared to those calculated with OLR. It means that all the data fit well with WLR for pesticide residue analysis. It was estimated that, regardless of the actual concentration range of the calibration, relative uncertainty at the lowest calibrated level ranged between 0.3% and 113.7% for OLR and between 0.2% and 22.1% for WLR. At or above 1/3 of the calibrated range, uncertainty of calibration curve ranged between 0.1% and 16.3% for OLR and 0% and 12.2% for WLR, and therefore, the two methods gave comparable results.

Separation of thorium (IV) from lanthanide concentrate (LC) and water leach purification (WLP) residue

International Nuclear Information System (INIS)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-01-01

Thorium (IV) content in industrial residue produced from rare earth elements production industry is one of the challenges to Malaysian environment. Separation of thorium from the lanthanide concentrate (LC) and Water Leach Purification (WLP) residue from rare earth elements production plant is described. Both materials have been tested by sulphuric acid and alkaline digestions. Th concentrations in LC and WLP were determined to be 1289.7 ± 129 and 1952.9±17.6 ppm respectively. The results of separation show that the recovery of Th separation from rare earth in LC after concentrated sulphuric acid dissolution and reduction of acidity to precipitate Th was found 1.76-1.20% whereas Th recovery from WLP was less than 4% after concentrated acids and alkali digestion processes. Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) was used to determine Th concentrations in aqueous phase during separation stages. This study indicated that thorium maybe exists in refractory and insoluble form which is difficult to separate by these processes and stays in WLP residue as naturally occurring radioactive material (NORM)

Resistance to deltamethrine in two populations of Aedes aegypti (Diptera, Culicidae from Peru

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Julio Chávez

2013-05-01

Full Text Available The objective of the present work was to determine the resistance levels to deltamethrine in two populations of Aedes aegypti from Peru. Bioassays in adults were carried out following the methodology of the World Health Organization. We met resistance in the Sullana population with 70% of mortality and susceptibility in the population The Future El Porvenir with 99% of mortality.

Irritant and repellent responses of Anopheles harrisoni and Anopheles minimus upon exposure to bifenthrin or deltamethrin using an excito-repellency system and a live host.

Science.gov (United States)

Kongmee, Monthathip; Boonyuan, Wasana; Achee, Nicole L; Prabaripai, Atchariya; Lerdthusnee, Kriangkrai; Chareonviriyaphap, Theeraphap

2012-03-01

Feeding responses of Anopheles harrisoni and An. minimus were evaluated following exposure to 2 pyrethroid insecticides, bifenthrin or deltamethrin, using an excito-repellency test system in the presence and absence of live host cues. The results demonstrated that contact irritancy was the primary action of bifenthrin or deltamethrin in both mosquito species. There was no noncontact repellency effect elicited by either insecticide. Anopheles minimus showed rapid escape response with high mortality rates following direct contact with deltamethrin in the absence of a host and delayed escape responses when a host was present. Similarly, exposure of An. minimus to bifenthrin also elicited a delayed escape response in the presence of a host but with lower mortality rates. In experiments using An. harrisoni, the presence or absence of a host had no significant effect on behavioral responses to either insecticide (P > 0.05). We conclude that deltamethrin elicited stronger irritant chemical effects than bifenthrin but that behavioral responses in vector populations are dampened in the presence of an available host. This information is useful for estimating probability of pathogen transmission when using irritant chemicals in proximity to a blood-meal source.

The Effect of Kaffir Lime Leaves Distillation Residue Oleoresin Concentration on Active Paper Packaging Characteristics

Science.gov (United States)

Kawiji; Utami, R.; Ulum, S.; Khasanah, L. U.; Manuhara, G. J.; Atmaka, W.

2018-03-01

Oleoresin of kaffir lime leaves distillation residue still contains some active compounds such as Citronellal, β-Citronellol, and Linalool which potential to incorporated on the active paper packaging. The purposes of this study were to determine the effect of kaffir lime leaves distillation residue oleoresin concentration on the physical characteristics, sensory characteristics, and antimicrobial activity of the active paper packaging incorporated with kaffir lime leaves distillation residue oleoresin and to determine the functional groups of active paper packaging. The concentration of kaffir lime leaves distillation residue oleoresin were varied at 0%, 2%, 4% and 6%. The result showed that the addition of kaffir lime leaves distillation residue oleoresin increased the thickness and moisture content of the paper and decreased the tensile strengths and folding endurances of active paper packaging. The microbial inhibition tends to increase along with the higher oleoresin concentration addition. Aromatic CH group were found at a wavelength of 897.90 cm-1 of on paper packaging with 2% oleoresin indicated as functional aromatic functional group allegedly obtained from the kaffir lime leaves oleoresin.

Pesticide residue evaluation in major staple food items of Ethiopia using the QuEChERS method: a case study from the Jimma Zone.

Science.gov (United States)

Mekonen, Seblework; Ambelu, Argaw; Spanoghe, Pieter

2014-06-01

Samples of maize, teff, red pepper, and coffee (green bean and coffee bean with pulp) were collected from a local market in the Jimma Zone, Ethiopia. Samples were analyzed for the occurrence of cypermethrin, permethrin, deltamethrin, chlorpyrifos ethyl, DTT and its metabolites, and endosulfan (α, β). In the analytical procedure, the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction methodology with dispersive solid phase extraction clean up (d-SPE) technique was applied. Validation of the QuEChERS method was satisfactory. Recovery percentages of most pesticides were in the range of 70% to 120%, with good repeatability (%relative standard deviation coffee bean. Residues of DDT in coffee pulp significantly differed (p < 0.01) from other food items except for red pepper. The concentration of pesticides in the food items varied from 0.011 mg/kg to 1.115 mg/kg. All food items contained 1 or more pesticides. Two-thirds of the samples had residues below corresponding maximum residue limits, and the remaining one-third of samples were above the maximum residue limits. These results indicate the need for a good pesticide monitoring program to evaluate consumer risk for the Ethiopian people. © 2014 SETAC.

Resistance Status to the Insecticides Temephos, Deltamethrin, and Diflubenzuron in Brazilian Aedes aegypti Populations

Science.gov (United States)

Viana-Medeiros, Priscila Fernandes; Araújo, Simone Costa; Martins, Ademir J.; Lima, José Bento Pereira

2016-01-01

Insecticides are still largely applied in public health to control disease vectors. In Brazil, organophosphates (OP) and pyrethroids (PY) are used against Aedes aegypti for years. Since 2009 Insect Growth Regulators (IGR) are also employed in the control of larvae. We quantified resistance to temephos (OP), deltamethrin (PY), and diflubenzuron (IGR) of A. aegypti samples from 12 municipalities distributed throughout the country, collected between 2010 and 2012. High levels of resistance to neurotoxic insecticides were detected in almost all populations: RR95 to temephos varied between 4.0 and 27.1; the lowest RR95 to deltamethrin was 13.1, and values higher than 70.0 were found. In contrast, all samples were susceptible to diflubenzuron (RR95 < 2.3). Biochemical tests performed with larvae and adults discarded the participation of acetylcholinesterase, the OP target, and confirmed involvement of the detoxifying enzymes esterases, mixed function oxidases, and glutathione-S-transferases. The results obtained were discussed taking into account the public chemical control component and the increase in the domestic use of insecticides during dengue epidemic seasons in the evaluated municipalities. PMID:27419140

Pesticide Residues on Three Cut Flower Species and Potential Exposure of Florists in Belgium

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Khaoula Toumi

2016-09-01

Full Text Available In order to assess the prevalence of pesticide contamination and the risk of florists’ exposure when handling cut flowers, sampling and analysis of 90 bouquets of the most commonly sold cut flowers in Belgium (50 bouquets of roses; 20 of gerberas, and 20 of chrysanthemums were carried out. The bouquets were collected from 50 florists located in the seven largest cities of Belgium (Antwerp, Brussels, Charleroi, Ghent, Leuven, Liege, and Namur and from five supermarkets located in the different regions. To have a better understanding of the route of exposure and professional practices a questionnaire was also addressed to a group of 25 florists who volunteered to take part in the survey. All florists were interviewed individually when collecting the questionnaire. The residual pesticide deposit values on cut flowers were determined in an accredited laboratory using a multi-residue (QuEChERS Quick Easy Cheap Effective Rugged Safe method and a combination of gas chromatography (GC and liquid chormatograhphy (LC analysis. A total of 107 active substances were detected from all samples; i.e., an average of about 10 active substances per bouquet. The most severely contaminated bouquet accumulated a total concentration of residues up to 97 mg/kg. Results show that roses are the most contaminated cut flowers; with an average of 14 substances detected per sample and a total concentration per rose sample of 26 mg/kg. Some active substances present an acute toxicity (acephate, methiocarb, monocrotophos, methomyl, deltamethrin, etc. and exposure can generate a direct effect on the nervous system of florists. Nevertheless, fungicides (dodemorph, propamocarb, and procymidone were the most frequently detected in samples and had the highest maximum concentrations out of all the active substances analysed. Dodemorph was the most frequently detected substance with the highest maximum concentration (41.9 mg/kg measured in the rose samples. It appears from the

Susceptibility and resistance to deltamethrin of wild and domestic populations of Triatoma infestans (Reduviidae: Triatominae in Bolivia: new discoveries

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Stéphanie Depickère

2012-12-01

Full Text Available Bolivia is a high-endemic country for Chagas disease, for which the principal vector is Triatoma infestans (Triatominae. This is a mainly domestic species that is also found in the wild environment. Recently, an increasing number of studies have shown the importance of Triatominae resistance to insecticides, especially in Bolivia. Data regarding the susceptibility/resistance of wild and domestic populations of T. infestans to deltamethrin are presented. For the first time, domestic populations of the department of Santa Cruz were tested, showing low resistance. Although most of the wild populations were found to be susceptible to deltamethrin, three populations from three departments showed a mortality rate of less than 100%. This result is emphasised here.

DEVELOPMENT OF A PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR DELTAMETHRIN IN THE ADULT MALE SPRAGUE-DAWLEY RAT

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Deltamethrin (DLT) is a Type II pyrethroid insecticide widely used in agriculture and public health. DLT is a potent neurotoxin that is primarily cleared from the body by metabolism. To better understand the dosimetry of DLT in the central nervous system, a physiologically based ...

SEASON OF DELTAMETHRIN APPLICATION AFFECTS FLEA AND PLAGUE CONTROL IN WHITE-TAILED PRAIRIE DOG (CYNOMYS LEUCURUS) COLONIES, COLORADO, USA.

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Tripp, Daniel W; Streich, Sean P; Sack, Danielle A; Martin, Daniel J; Griffin, Karen A; Miller, Michael W

2016-07-01

In 2008 and 2009, we evaluated the duration of prophylactic deltamethrin treatments in white-tailed prairie dog ( Cynomys leucurus ) colonies and compared effects of autumn or spring dust application in suppressing flea numbers and plague. Plague occurred before and during our experiment. Overall, flea abundance tended to increase from May or June to September, but it was affected by deltamethrin treatment and plague dynamics. Success in trapping prairie dogs (animals caught/trap days) declined between June and September at all study sites. However, by September trap success on dusted sites (19%; 95% confidence interval [CI] 16-22%) was about 15-fold greater than on undusted control sites (1%; CI 0.3-4%; P≤0.0001). Applying deltamethrin dust as early as 12 mo prior seemed to afford some protection to prairie dogs. Our data showed that dusting even a portion of a prairie dog colony can prolong its persistence despite epizootic plague. Autumn dusting may offer advantages over spring in suppressing overwinter or early-spring flea activity, but timing should be adjusted to precede the annual decline in aboveground activity for hibernating prairie dog species. Large colony complexes or collections of occupied but fragmented habitat may benefit from dusting some sites in spring and others in autumn to maximize flea suppression in a portion of the complex or habitat year-round.

Combined acute ecotoxicity of malathion and deltamethrin to Daphnia magna (Crustacea, Cladocera): comparison of different data analysis approaches.

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Toumi, Héla; Boumaiza, Moncef; Millet, Maurice; Radetski, Claudemir Marcos; Camara, Baba Issa; Felten, Vincent; Masfaraud, Jean-François; Férard, Jean-François

2018-04-19

We studied the combined acute effect (i.e., after 48 h) of deltamethrin (a pyrethroid insecticide) and malathion (an organophosphate insecticide) on Daphnia magna. Two approaches were used to examine the potential interaction effects of eight mixtures of deltamethrin and malathion: (i) calculation of mixture toxicity index (MTI) and safety factor index (SFI) and (ii) response surface methodology coupled with isobole-based statistical model (using generalized linear model). According to the calculation of MTI and SFI, one tested mixture was found additive while the two other tested mixtures were found no additive (MTI) or antagonistic (SFI), but these differences between index responses are only due to differences in terminology related to these two indexes. Through the surface response approach and isobologram analysis, we concluded that there was a significant antagonistic effect of the binary mixtures of deltamethrin and malathion that occurs on D. magna immobilization, after 48 h of exposure. Index approaches and surface response approach with isobologram analysis are complementary. Calculation of mixture toxicity index and safety factor index allows identifying punctually the type of interaction for several tested mixtures, while the surface response approach with isobologram analysis integrates all the data providing a global outcome about the type of interactive effect. Only the surface response approach and isobologram analysis allowed the statistical assessment of the ecotoxicological interaction. Nevertheless, we recommend the use of both approaches (i) to identify the combined effects of contaminants and (ii) to improve risk assessment and environmental management.

Pesticides in persimmons, jujubes and soil from China: Residue levels, risk assessment and relationship between fruits and soils.

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Liu, Yihua; Li, Shiliang; Ni, Zhanglin; Qu, Minghua; Zhong, Donglian; Ye, Caifen; Tang, Fubin

2016-01-15

Extreme and uncontrolled usage of pesticides produces a number of problems for vegetation and human health. In this study, the existence of organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and fungicides (FUs) were investigated in persimmons/jujubes and their planted soils, which were collected from China. One OP (dimethoate), three OCs (DDT, quintozene and aldrin), six PYs (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) and two FUs (triadimefon and buprofezin) were found in 36.4% of persimmons and 70.8% of jujubes, with concentrations from 1.0 μg/kg to 2945.0 μg/kg. The most frequently detected pesticides in the two fruits were fenpropathrin in persimmons and cypermethrin in jujubes, with the detection frequencies of 30.0% and 22.7%, respectively. The residues of 4.5% (persimmon) and 25.0% (jujube) of samples were higher than the maximum residue limits (MRLs) of China. Compared with the fruits, more types of pesticides and higher residues were observed in their planted soils. The most frequently detected pesticides were HCH in persimmon soil and DDT in jujube soil, with the detection frequencies of 10.9% and 12.7%, respectively. For the tested samples, 39.1% of fruit samples and 63.0% of soil samples with multiple residues (containing more than two pesticides) were noted, even up to 8 residues in fruits and 14 residues in soils. Except for cyhalothrin, the other short-term risks for the tested pesticides in the fruits were below 10%, and the highest long-term risk was 14.13% for aldrin and dieldrin. There was no significant health risk for consumers via consumption of the two fruits. Copyright © 2015 Elsevier B.V. All rights reserved.

Combination of diatomaceous earth and powder deltamethrin for insect control in stored corn Combinação de terra de diatomácea e deltametrina em pó para o controle de insetos em milho armazenado

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Fabiane Cristina Ceruti

2005-12-01

Full Text Available The use of diatomaceous earth (DE is a very efficient insect control measure in stored grain IPM due to its low cost, easy application, reduction of active ingredient residues, lower environmental contamination and operator safety. The objective of this research was to evaluate the efficacy of different dosages of DE mixed with powder deltamethrin for controlling Sitophilus zeamais in stored corn. Samples of 100 g of clean and dry corn, in three replicates, were submitted to the following treatments: DE (Keepdry®, at the dosages of 500, 750 and 1000 g/t; powder deltamethrin (K-Obiol® at 0,5 g a.i. /t and 1,0 g a.i. /t; and combinations of the lowest and highest DE dosages with the two dosages of deltamethrin. Thirty adults of S. zeamais were placed in each vial with the treated grains and kept in environment chambers at 25ºC. Mortality was evaluated from the 1st to the 28th day. In the treatments mixing DE with deltamethrin or deltamethrin alone, the mortalyti was registered since the first day. In the treatments using only DE, the first dead insects were recorded after the 3rd day, especially in the highest dosages. After the 7th day, however, there was no statistical difference among all treatments, except for the lowest dosage of DE which reached a satisfactory control level only by the 14th day. It was concluded that treatments using DE combined with low dosages of powder deltamethrin represent an efficient control measure against S. zeamais in stored corn because insect mortality is faster than in treatments using DE alone and residues of active ingredients are much lower than using the insecticide in high dosages.O uso de terra de diatomácea (TD representa uma medida de controle importante em programas de MIP de armazenamento devido ao baixo custo, facilidade de aplicação, redução do nível de resíduos de ingrediente ativo e da contaminação ambiental e maior segurança para o operador. O objetivo desta pesquisa foi avaliar a

Effects of the β1 auxiliary subunit on modification of Rat Na{sub v}1.6 sodium channels expressed in HEK293 cells by the pyrethroid insecticides tefluthrin and deltamethrin

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He, Bingjun [College of Life Sciences, Nankai University, Tianjin 300071 (China); Soderlund, David M., E-mail: dms6@cornell.edu [Department of Entomology, Cornell University, Geneva, NY 14456 (United States)

2016-01-15

We expressed rat Na{sub v}1.6 sodium channels with or without the rat β1 subunit in human embryonic kidney (HEK293) cells and evaluated the effects of the pyrethroid insecticides tefluthrin and deltamethrin on whole-cell sodium currents. In assays with the Na{sub v}1.6 α subunit alone, both pyrethroids prolonged channel inactivation and deactivation and shifted the voltage dependence of channel activation and steady-state inactivation toward hyperpolarization. Maximal shifts in activation were ~ 18 mV for tefluthrin and ~ 24 mV for deltamethrin. These compounds also caused hyperpolarizing shifts of ~ 10–14 mV in the voltage dependence of steady-state inactivation and increased in the fraction of sodium current that was resistant to inactivation. The effects of pyrethroids on the voltage-dependent gating greatly increased the size of sodium window currents compared to unmodified channels; modified channels exhibited increased probability of spontaneous opening at membrane potentials more negative than the normal threshold for channel activation and incomplete channel inactivation. Coexpression of Na{sub v}1.6 with the β1 subunit had no effect on the kinetic behavior of pyrethroid-modified channels but had divergent effects on the voltage-dependent gating of tefluthrin- or deltamethrin-modified channels, increasing the size of tefluthrin-induced window currents but decreasing the size of corresponding deltamethrin-induced currents. Unexpectedly, the β1 subunit did not confer sensitivity to use-dependent channel modification by either tefluthrin or deltamethrin. We conclude from these results that functional reconstitution of channels in vitro requires careful attention to the subunit composition of channel complexes to ensure that channels in vitro are faithful functional and pharmacological models of channels in neurons. - Highlights: • We expressed Na{sub v}1.6 sodium channels with or without β1 subunits in HEK293 cells. • Tefluthrin and deltamethrin

Monitoring of Pesticide Residues in Commonly Used Fruits and Vegetables in Kuwait.

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Jallow, Mustapha F A; Awadh, Dawood G; Albaho, Mohammed S; Devi, Vimala Y; Ahmad, Nisar

2017-07-25

The presence of pesticide residues in primary and derived agricultural products raises serious health concerns for consumers. The aim of this study was to assess the level of pesticide residues in commonly consumed fruits and vegetables in Kuwait. A total of 150 samples of different fresh vegetables and fruits were analyzed for the presence of 34 pesticides using the quick easy cheap effective rugged and safe (QuEChERS) multi-residue extraction, followed by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC - MS / MS). Pesticide residues above the maximum residue limits (MRL) were detected in 21% of the samples and 79% of the samples had no residues of the pesticides surveyed or contained residues below the MRL. Multiple residues were present in 40% of the samples with two to four pesticides, and four samples were contaminated with more than four pesticide residues. Of the pesticides investigated, 16 were detected, of which imidacloprid, deltamethrin, cypermethrin, malathion, acetamiprid, monocrotophos, chlorpyrifos-methyl, and diazinon exceeded their MRLs. Aldrin, an organochlorine pesticide, was detected in one apple sample, with residues below the MRL. The results indicate the occurrence of pesticide residues in commonly consumed fruits and vegetables in Kuwait, and pointed to an urgent need to develop comprehensive intervention measures to reduce the potential health risk to consumers. The need for the regular monitoring of pesticide residues and the sensitization of farmers to better pesticide safety practices, especially the need to adhere to recommended pre-harvest intervals is recommended.

Monitoring of Pesticide Residues in Commonly Used Fruits and Vegetables in Kuwait

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Mustapha F. A. Jallow

2017-07-01

Full Text Available The presence of pesticide residues in primary and derived agricultural products raises serious health concerns for consumers. The aim of this study was to assess the level of pesticide residues in commonly consumed fruits and vegetables in Kuwait. A total of 150 samples of different fresh vegetables and fruits were analyzed for the presence of 34 pesticides using the quick easy cheap effective rugged and safe (QuEChERS multi-residue extraction, followed by gas chromatography-mass spectrometry (GC-MS or liquid chromatography-tandem mass spectrometry (LC-MS/MS. Pesticide residues above the maximum residue limits (MRL were detected in 21% of the samples and 79% of the samples had no residues of the pesticides surveyed or contained residues below the MRL. Multiple residues were present in 40% of the samples with two to four pesticides, and four samples were contaminated with more than four pesticide residues. Of the pesticides investigated, 16 were detected, of which imidacloprid, deltamethrin, cypermethrin, malathion, acetamiprid, monocrotophos, chlorpyrifos-methyl, and diazinon exceeded their MRLs. Aldrin, an organochlorine pesticide, was detected in one apple sample, with residues below the MRL. The results indicate the occurrence of pesticide residues in commonly consumed fruits and vegetables in Kuwait, and pointed to an urgent need to develop comprehensive intervention measures to reduce the potential health risk to consumers. The need for the regular monitoring of pesticide residues and the sensitization of farmers to better pesticide safety practices, especially the need to adhere to recommended pre-harvest intervals is recommended.

Microscopic analysis of Spodoptera frugiperda (Lepidoptera: Noctuidae) embryonic development before and after treatment with azadirachtin, lufenuron, and deltamethrin.

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Correia, Alicely A; Wanderley-Teixeira, Valéria; Teixeira, Alvaro A C; Oliveira, José V; Gonçalves, Gabriel G A; Cavalcanti, MaríIia G S; Brayner, Fábio A; Alves, Luiz C

2013-04-01

The botanical insecticides, growth regulators, and pyrethroids have an effect on the biology of Spodoptera frugiperda (Smith). However, no emphasis has been given to the effect of these insecticides on embryonic development of insects, in histological level. Thus, this research aimed to examine by light and scanning electron microscopy S. frugiperda eggs and to describe the embryonic development, before and after immersion treatment, using commercial concentrations and lower concentrations than commercial ones, of the compounds lufenuron (Match), azadirachtin (AzaMax), and deltamethrin (Decis-positive control). For light microscopy semithin sections of eggs were used, and for scanning electron microscopy, images of the surface of eggs, treated and untreated with insecticides. The morphological characteristics of S. frugiperda eggs, in general, were similar to those described in the literature for most of the insects in the order Lepidoptera. Spherical eggs slightly flattened at the poles, with chorion, yolk, vitelline membrane, and embryo formation. In both microscopic analysis, we observed that insecticides acted immediately and independent of concentration, resulting absence, or incomplete embryo, presented yolk granules widely dispersed, without vitellophage formation, chorion disintegration, disorganized blastoderm, presenting vacuoles, yolk region with amorphous cells, and formation of completely uncharacterized appendages. Thus, we conclude that the compounds lufenuron and azadirachtin interfere on S. frugiperda embryonic development.

Evaluation of Bifenthrin and Deltamethrin Barrier Sprays for Mosquito Control in Eastern North Carolina.

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Richards, Stephanie L; Volkan, Josh K; Balanay, Jo Anne G; Vandock, Kurt

2017-11-07

Mosquitoes are a nuisance and potentially transmit pathogens causing numerous diseases worldwide. Homeowners and others may hire private companies to alleviate mosquito-related issues. Here, two pyrethroids (Suspend Polyzone [deltamethrin] and Bifen Insecticide/Termiticide [bifenthrin]) were evaluated on properties in North Carolina for 23 wk from 18 May through 19 October 2015. Properties were treated using backpack mist blowers every 21 d. At 17 fixed sampling locations, Centers for Disease Control and Prevention carbon dioxide-baited traps were deployed overnight once/week for the duration of the experiment. Oviposition traps were deployed weekly at the same locations. Differences were observed in mosquito abundance between neighborhoods, treatments, and weeks and differences varied between species. Mosquito abundance was generally significantly higher in traps placed on control properties (no insecticide) compared to traps placed on treatment properties. Bifenthrin and deltamethrin showed differences from each other in efficacy, but this varied between neighborhoods and species. Future studies could test the efficacy of barrier sprays at different application frequencies and/or in conjunction with weather monitoring. Coupled with regular mosquito surveillance and using integrated pest management principles, barrier sprays can be an effective tool for suppression of mosquito populations. © The Authors 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.

Sorption of lambda-cyhalothrin, cypermethrin, deltamethrin and fenvalerate to quartz, corundum, kaolinite and montmorillonite.

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Oudou, H Chaaieri; Hansen, H C Bruun

2002-12-01

Sorption to mineral surfaces may be important for retention and degradation of hydrophobic pesticides in subsoils and aquifers poor in organic matter. In this work the title pyrethroids have been used to investigate selective interactions with the surfaces of four minerals. Sorption of the four pyrethroids was quantified in batch experiments with initial pyrethroid concentrations of 1-100 microg/l. Sorption to centrifuge tubes used in the batch experiments accounted for 25-60% of total sorption. Net sorption was obtained from total sorption after subtracting the amounts of pyrethroids sorbed to centrifuge tubes used. All isotherms could be fitted by the Freundlich equation with n ranging between 0.9 and 1.1. Bonding affinities per unit surface area decreased in the order: corundum > quartz > montmorillonite approximately equal kaolinite. A similar sequence as found for the total surface tension of the minerals. All minerals showed the same selectivity order with respect to sorption affinity of the four pyrethroids: lambda-cyhalothrin > deltamethrin > cypermethrin > fenvalerate, which shows that the most hydrophobic compound is sorbed most strongly. Stereochemical properties of the four pyrethroid formulations may also contribute to the selectivity pattern.

Virgin olive oil ameliorates deltamethrin-induced nephrotoxicity in mice: A biochemical and immunohistochemical assessment.

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Khalatbary, Ali Reza; Ahmadvand, Hassan; Ghabaee, Davood Nasiry Zarrin; Malekshah, Abbasali Karimpour; Navazesh, Azam

2016-01-01

A major class of synthetic pyrethroid insecticide, deltamethrin (DM), can elicit pathophysiological effects through oxidative stress in non-targeted organisms such as mammals. There is accumulating evidence that virgin olive oil (VOO), a rich source of polyphenolic components, have anti-oxidant, anti-inflammatory, and anti-apoptotic properties. This study aimed to determine the protective and ameliorative effects of VOO against DM-induced nephrotoxicity. Mice were randomly divided into four equal groups: DM group, DM plus VOO group, VOO group, and vehicle group. Five weeks after gavaging, kidney samples were taken for biochemical assessment of malondialdehyde (MDA), glutathione (GSH) and catalase (CAT), and for immunohistochemical assessment of caspase-3, cyclooxygenase-2 (cox-2) and poly (ADP-ribose) polymerase (PARP). The MDA level in kidney was increased in the DM group, which was significantly decreased after VOO administration in the DM plus VOO group. The GSH level and CAT activiy in kidney were decreased in the DM group, which were significantly increased after VOO administration in the DM plus VOO group. Greater expression of caspase-3, cox-2, and PARP could be detected in the DM group, which was significantly attenuated in the DM plus VOO group. Also, the histopathological changes which were detected in the DM group attenuated after VOO consumption. Virgin olive oil exerted protective effects against deltamethrin-induced nephrotoxicity, which might be associated with its anti-apoptotic, anti-inflammatory, and anti-oxidative properties.

The residual C concentration control for low temperature growth p-type GaN

International Nuclear Information System (INIS)

Liu Shuang-Tao; Zhao De-Gang; Yang Jing; Jiang De-Sheng; Liang Feng; Chen Ping; Zhu Jian-Jun; Liu Zong-Shun; Li Xiang; Liu Wei; Xing Yao; Zhang Li-Qun

2017-01-01

In this work, the influence of C concentration to the performance of low temperature growth p-GaN is studied. Through analyses, we have confirmed that the C impurity has a compensation effect to p-GaN. At the same time we have found that several growth and annealing parameters have influences on the residual C concentration: (i) the C concentration decreases with the increase of growth pressure; (ii) we have found there exists a Ga memory effect when changing the Cp 2 Mg flow which will lead the growth rate and C concentration increase along the increase of Cp 2 Mg flow; (iii) annealing outside of metal–organic chemical vapor deposition (MOCVD) could decrease the C concentration while in situ annealing in MOCVD has an immobilization role to C concentration. (paper)

Deltamethrin flea-control preserves genetic variability of black-tailed prairie dogs during a plague outbreak

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Jones, P.H.; Biggins, D.E.; Eads, D.A.; Eads, S.L.; Britten, H.B.

2012-01-01

Genetic variability and structure of nine black-tailed prairie dog (BTPD, Cynomys ludovicianus) colonies were estimated with 15 unlinked microsatellite markers. A plague epizootic occurred between the first and second years of sampling and our study colonies were nearly extirpated with the exception of three colonies in which prairie dog burrows were previously dusted with an insecticide, deltamethrin, used to control fleas (vectors of the causative agent of plague, Yersinia pestis). This situation provided context to compare genetic variability and structure among dusted and non-dusted colonies pre-epizootic, and among the three dusted colonies pre- and post-epizootic. We found no statistical difference in population genetic structures between dusted and non-dusted colonies pre-epizootic. On dusted colonies, gene flow and recent migration rates increased from the first (pre-epizootic) year to the second (post-epizootic) year which suggested dusted colonies were acting as refugia for prairie dogs from surrounding colonies impacted by plague. Indeed, in the dusted colonies, estimated densities of adult prairie dogs (including dispersers), but not juveniles (non-dispersers), increased from the first year to the second year. In addition to preserving BTPDs and many species that depend on them, protecting colonies with deltamethrin or a plague vaccine could be an effective method to preserve genetic variability of prairie dogs. ?? 2011 Springer Science+Business Media B.V.

Variability of pesticide residues in eggplant units collected from a field trial and marketplaces in Greece.

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Prodhan, Mohammad Dalower Hossain; Papadakis, Emmanouil-Nikolaos; Papadopoulou-Mourkidou, Euphemia

2018-04-01

Variability of pesticide residues among food items is very important when assessing the risks and food safety for the consumers. Therefore, the present study was undertaken to estimate the unit-to-unit residue variability factors for eggplant. In total, 120 samples from a trial field and 142 samples from different marketplaces in Thessaloniki, Greece, were collected to estimate the variability of pesticide residues in eggplant units. They were extracted by the QuEChERS method and the residues were determined by LC-MS/MS. For the field samples, the unit-to-unit variability factors (VFs) obtained for cypermethrin and deltamethrin residues were 2.54 and 2.51, respectively. The mean residue levels of both pesticides were higher in the composite samples than in the individual samples. The average VFs for the marketplace samples was 3.89. The eggplant units exposed to pesticides were higher in residues than the non-exposed units. The variability factors obtained in the marketplace samples were higher than those in the samples collected from the field trial. A default VF value of 3 for field trials is appropriate for use when assessing the acute dietary intake but a VF for the marketplace samples should be reconsidered with a larger data. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Estimation of the residual bromine concentration after disinfection of cooling water by statistical evaluation.

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Megalopoulos, Fivos A; Ochsenkuehn-Petropoulou, Maria T

2015-01-01

A statistical model based on multiple linear regression is developed, to estimate the bromine residual that can be expected after the bromination of cooling water. Make-up water sampled from a power plant in the Greek territory was used for the creation of the various cooling water matrices under investigation. The amount of bromine fed to the circuit, as well as other important operational parameters such as concentration at the cooling tower, temperature, organic load and contact time are taken as the independent variables. It is found that the highest contribution to the model's predictive ability comes from cooling water's organic load concentration, followed by the amount of bromine fed to the circuit, the water's mean temperature, the duration of the bromination period and finally its conductivity. Comparison of the model results with the experimental data confirms its ability to predict residual bromine given specific bromination conditions.

Residual antibiofilm effects of various concentrations of double antibiotic paste used during regenerative endodontics after different application times.

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Jenks, Daniel B; Ehrlich, Ygal; Spolnik, Kenneth; Gregory, Richard L; Yassen, Ghaeth H

2016-10-01

We investigated the residual antibiofilm effects of different concentrations of double antibiotic paste (DAP) applied on radicular dentin for 1 or 4 weeks. Dentin samples were prepared (n=120), sterilized and pretreated for 1 or 4 weeks with the clinically used concentration of DAP (500mg/mL), low concentrations of DAP (1, 5 or 50mg/mL) loaded into a methylcellulose system, calcium hydroxide (Ca(OH) 2 ), or placebo paste. After the assigned treatment time, treatment pastes were rinsed off and the samples were kept independently in phosphate buffered saline for 3 weeks. Pretreated dentin samples were then inoculated with Enterococcus faecalis and bacterial biofilms were allowed to grow for an additional 3 weeks. Biofilms were then retrieved from dentin using biofilm disruption assays, diluted, spiral plated, and quantified. Fisher's Exact and Wilcoxon rank sum tests were used for statistical comparisons (α=0.05). Dentin pretreatment for 4 weeks with 5, 50 or 500mg/mL of DAP demonstrated significantly higher residual antibiofilm effects and complete eradication of E. faecalis biofilms in comparison to a 1 week pretreatment with similar concentrations. However, dentin pretreated with 1mg/mL of DAP or Ca(OH) 2 did not provide a substantial residual antibiofilm effect regardless of the application time. Dentin pretreatment with 5mg/mL of DAP or higher for 4 weeks induced significantly higher residual antibiofilm effects in comparison to a 1 week pretreatment with the same concentrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Geographical Variation of Deltamethrin Susceptibility of Triatoma infestans (Hemiptera: Reduviidae) in Argentina With Emphasis on a Resistant Focus in the Gran Chaco.

Science.gov (United States)

Fronza, G; Toloza, A C; Picollo, M I; Spillmann, C; Mougabure-Cueto, G A

2016-07-01

Chagas disease is one of the most important parasitic infections in Latin America. The main vector of the protozoan Trypanosoma cruzi in America is Triatoma infestans, a blood-sucking triatomine bug who is widely distributed in the Gran Chaco ecoregion. Control programs in endemic countries are focused in the elimination of triatomine vectors with pyrethroid insecticides. However, chemical control has failed in the Gran Chaco over the last two decades because of several factors. Previous studies have reported the evolution of different levels of resistance to deltamethrin in Tri. infestans Recently, very high resistance has been found in the central area of the Argentine Gran Chaco. However, the origin and the extension of this remarkably resistant focus remain unknown. The aim of this study was to evaluate the geographical variation of deltamethrin susceptibility of Tri. infestans in different endemic provinces of Argentina, with emphasis in the center of the Argentine Gran Chaco ecoregion where this main vector has not been reduced. Populations of Mendoza, San Juan, Santiago del Estero, and Tucumán provinces were all susceptible. Resistant populations were only detected in the province of Chaco, where a mosaic resistant focus was described at the Güemes Department. It was characterized into three pyrethroid resistance categories: susceptible, low, and highly resistant populations. We found the populations with the highest resistance levels to deltamethrin, with resistant ratios over 1000. © 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.

The impact of pesticides use on surface water and groundwater: a case study in the Kadjebi District, Volta Region, Ghana

International Nuclear Information System (INIS)

Suraj, S. I.

2015-07-01

respondents reported clinical symptoms of pesticide poisoning such as nausea, headache, blurred vision, eye irritation, dizziness, vomiting and skin irritation. About 51% of water samples analyzed showed positive detections of pesticide residues while all sediments samples showed positive detections of pesticides residues varying from one to five different types of pesticides residues. The common pesticides residues found in the samples were Deltamethrine, Cyfluthrin, Cypermethrin, Dieldrin, Fenvaerate, Lambda-cyhal, p,p’ DDT. Synthetic pyrethroids (72%) were the dominant residues detected. Deltamethrine, Cyfluthrin, Cypermethrin, Dieldrin, Fenvaerate, were found in the sediments with concentration range of 0.001 mg/kg to 0.014 mg/kg. Deltamethrine, Cyfluthrin, Cypermethrin, Dieldrin and p,p’ DDT were detected in the surface water with concentration which varied from 0.001 μg/L to 0.007 μg/L. The waters in the study area were generally slightly acidic to alkaline, soft and fresh. The major ion concentration dominance patterns observed for surface water in the study were in the order Na + > Ca 2+ > Mg 2+ > K + > and SO4 2- > Cl - > NO 3 - > PO 4 3- indicating partial cationic and anionic characteristics of fresh water. (au)

Levels of insecticide resistance to deltamethrin, malathion, and temephos, and associated mechanisms in Aedes aegypti mosquitoes from the Guadeloupe and Saint Martin islands (French West Indies).

Science.gov (United States)

Goindin, Daniella; Delannay, Christelle; Gelasse, Andric; Ramdini, Cédric; Gaude, Thierry; Faucon, Frédéric; David, Jean-Philippe; Gustave, Joël; Vega-Rua, Anubis; Fouque, Florence

2017-02-10

In the Guadeloupe and Saint Martin islands, Aedes aegypti mosquitoes are the only recognized vectors of dengue, chikungunya, and Zika viruses. For around 40 years, malathion was used as a mosquito adulticide and temephos as a larvicide. Since the European Union banned the use of these two insecticide molecules in the first decade of the 21st century, deltamethrin and Bacillus thuringiensis var. israelensis are the remaining adulticide and larvicide, respectively, used in Guadeloupe. In order to improve the management of vector control activities in Guadeloupe and Saint Martin, we investigated Ae. aegypti resistance to and mechanisms associated with deltamethrin, malathion, and temephos. Ae. aegypti mosquitoes were collected from six different localities of Guadeloupe and Saint Martin. Larvae were used for malathion and temephos bioassays, and adult mosquitoes for deltamethrin bioassays, following World Health Organization recommendations. Knockdown resistance (Kdr) genotyping for V1016I and F1534C mutations, and expression levels of eight enzymes involved in detoxification mechanisms were examined in comparison with the susceptible reference Bora Bora strain. Resistance ratios (RR 50 ) calculated for Ae. aegypti larvae showed high resistance levels to temephos (from 8.9 to 33.1-fold) and low resistance levels to malathion (from 1.7 to 4.4-fold). Adult females displayed moderate resistance levels to deltamethrin regarding the time necessary to affect 50% of individuals, varying from 8.0 to 28.1-fold. Molecular investigations on adult mosquitoes showed high resistant allele frequencies for V1016I and F1534C (from 85 to 96% and from 90 to 98%, respectively), as well as an overexpression of the glutathione S-transferase gene, GSTe2, the carboxylesterase CCEae3a, and the cytochrome genes 014614, CYP6BB2, CYP6M11, and CYP9J23. Ae. aegypti populations from Guadeloupe and Saint Martin exhibit multiple resistance to organophosphates (temephos and malathion), and

Pre-concentration of pesticide residues in environmental water samples using Silica nanoparticles and identification of residues By GC-MS method

OpenAIRE

Tentu. Nageswara Rao; A. Muralidhar Reddy; SNVS. Murthy; Prathipati Revathi; K. Suneel Kumar

2016-01-01

The silica nanoparticles prepared by stober’s mechanism by reaction of tetraethylorthosilicate (TEOS) with ammonia was tested for their adsorption capacity in the pre-concentration of residues of pesticides in water. The synthesized nanoparticles were characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and X-Ray Diffraction (XRD). The size of the silica nanoparticles were 50 to 250 nm. The solid phase extraction (SPE) cartridges were prepared by filling...

Predicting the concentration of residual methanol in industrial formalin using machine learning

OpenAIRE

Heidkamp, William

2016-01-01

In this thesis, a machine learning approach was used to develop a predictive model for residual methanol concentration in industrial formalin produced at the Akzo Nobel factory in Kristinehamn, Sweden. The MATLABTM computational environment supplemented with the Statistics and Machine LearningTM toolbox from the MathWorks were used to test various machine learning algorithms on the formalin production data from Akzo Nobel. As a result, the Gaussian Process Regression algorithm was found to pr...

Detection of the V1016G mutation in the voltage-gated sodium channel gene of Aedes aegypti (Diptera: Culicidae) by allele-specific PCR assay, and its distribution and effect on deltamethrin resistance in Thailand.

Science.gov (United States)

Stenhouse, Steven A; Plernsub, Suriya; Yanola, Jintana; Lumjuan, Nongkran; Dantrakool, Anchalee; Choochote, Wej; Somboon, Pradya

2013-08-30

Resistance to pyrethroid insecticides is widespread among populations of Aedes aegypti, the main vector for the dengue virus. Several different point mutations within the voltage-gated sodium channel (VGSC) gene contribute to such resistance. A mutation at position 1016 in domain II, segment 6 of the VGSC gene in Ae. aegypti leads to a valine to glycine substitution (V1016G) that confers resistance to deltamethrin. This study developed and utilized an allele-specific PCR (AS-PCR) assay that could be used to detect the V1016G mutation. The assay was validated against a number of sequenced DNA samples of known genotype and was determined to be in complete agreement. Larvae and pupae were collected from various localities throughout Thailand. Samples were reared to adulthood and their resistance status against deltamethrin was determined by standard WHO susceptibility bioassays. Deltamethrin-resistant and susceptible insects were then genotyped for the V1016G mutation. Additionally, some samples were genotyped for a second mutation at position 1534 in domain III (F1534C) which is also known to confer pyrethroid resistance. The bioassay results revealed an overall mortality of 77.6%. Homozygous 1016G individuals survived at higher rates than either heterozygous or wild-type (1016 V) mosquitoes. The 1016G mutation was significantly and positively associated with deltamethrin resistance and was widely distributed throughout Thailand. Interestingly, wild-type 1016 V mosquitoes tested were homozygous for the 1534C mutation, and all heterozygous mosquitoes were also heterozygous for 1534C. Mutant homozygous (G/G) mosquitoes expressed the wild-type (F/F) at position 1534. However, the presence of the 1534C mutation was not associated with deltamethrin resistance. Our bioassay results indicate that all populations sampled display some degree of resistance to deltamethrin. Homozygous 1016G mosquitoes were far likelier to survive such exposure. However, resistance in some

Residual concentrations of micropollutants in benthic mussels in the coastal areas of Bohai Sea, North China

International Nuclear Information System (INIS)

Liu Wenxin; Chen Jianglin; Lin Xiumei; Fan Yongsheng; Tao Shu

2007-01-01

Studies of heavy metals and organic pollutants in different benthic mussel species from Bohai Sea show that concentrations of Cd in mussels commonly exceed national biological quality standards. In addition, a site located in Laizhou Bay exhibits higher average concentrations of As, Hg and Pb with respect to the other sites. Residual levels of petroleum hydrocarbons at several sites in Liaodong Bay also exceed quality guidelines. Contents and compositional characteristics of DDT and its metabolites in mussels suggest the probability of recent inputs and potential ecological risks to the local benthic environment. - Residual Cd contents of mussels at many sites in Bohai Sea exceed national marine biological quality standard and compositions of DDT metabolites indicate recent inputs and potential risk

[Research on Identification and Determination of Pesticides in Apples Using Raman Spectroscopy].

Science.gov (United States)

Zhai, Chen; Peng, Yan-kun; Li, Yong-yu; Dhakal, Sagar; Xu, Tian-feng; Guo, Lang-hua

2015-08-01

Raman spectroscopy combined with chemometric methods has been thought to an efficient method for identification and determination of pesticide residues in fruits and vegetables. In the present research, a rapid and nondestructive method was proposed and testified based on self-developed Raman system for the identification and determination of deltamethrin and acetamiprid remaining in apple. The peaks of Raman spectra at 574 and 843 cm(-1) can be used to identify deltamethrin and acetamiprid, respectively, the characteristic peaks of deltamethrin and acetamiprid were still visible when the concentrations of the two pesticides were 0.78 and 0.15 mg · kg(-1) in apples samples, respectively. Calibration models of pesticide content were developed by partial least square (PLS) algorithm with different spectra pretreatment methods (Savitzky-Golay smoothing, first derivative transformation, second derivative transformation, baseline calibration, standard normal variable transformation). The baseline calibration methods by 8th order polynomial fitting gave the best results. For deltamethrin, the obtained prediction coefficient (Rp) value from PLS model for the results of prediction and gas chromatography measurement was 0.94; and the root mean square error of prediction (RMSEP) was 0.55 mg · kg(-1). The values of Rp and RMSEP were respective 0.85 and 0.12 mg · kg(-1) for acetamiprid. According to the detect performance, applying Raman technology in the nondestructive determination of pesticide residuals in apples is feasible. In consideration of that it needs no pretreatment before spectra collection and causes no damage to sample, this technology can be used in detection department, fruit and vegetable processing enterprises, supermarket, and vegetable market. The result of this research is promising for development of industrially feasible technology for rapid, nondestructive and real time detection of different types of pesticide with its concentration in apples. This

Inheritance and heritability of deltamethrin resistance under laboratory conditions of Triatoma infestans from Bolivia.

Science.gov (United States)

Gomez, Marinely Bustamante; Pessoa, Grasielle D'Avila Caldas; Rosa, Aline Cristine Luiz; Echeverria, Jorge Espinoza; Diotaiuti, Liléia Gonçalves

2015-11-16

Over the last few decades, pyrethroid-resistant in Triatoma infestans populations have been reported, mainly on the border between Argentina and Bolivia. Understanding the genetic basis of inheritance mode and heritability of resistance to insecticides under laboratory conditions is crucial for vector management and monitoring of insecticide resistance. Currently, few studies have been performed to characterize the inheritance mode of resistance to pyrethroids in T. infestans; for this reason, the present study aims to characterize the inheritance and heritability of deltamethrin resistance in T. infestans populations from Bolivia with different toxicological profiles. Experimental crosses were performed between a susceptible (S) colony and resistant (R) and reduced susceptibility (RS) colonies in both directions (♀ x ♂ and ♂ x ♀), and inheritance mode was determined based on degree of dominance (DO) and effective dominance (D(ML)). In addition, realized heritability (h(2)) was estimated based on a resistant colony, and select pressure was performed for two generations based on the diagnostic dose (10 ng. i. a. /nymph). The F1 progeny of the experimental crosses and the selection were tested by a standard insecticide resistance bioassay. The result for DO and D(ML) (Bolivia. The lethal doses (LD50) increase from one generation to another rapidly after selection pressure with deltamethrin. This suggests that resistance is an additive and cumulative factor, mainly in highly structured populations with limited dispersal capacity, such as T. infestans. This phenomenon was demonstrated for the first time for T. infestans in the present study. These results are very important for vector control strategies in problematic areas where high resistance ratios of T. infestans have been reported.

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.

Estimation of polycyclic aromatic hydrocarbon concentrations in the water column based on tissue residues in mussels and salmon: An equilibrium partitioning approach

International Nuclear Information System (INIS)

Neff, J.M.; Burns, W.A.

1996-01-01

Equilibrium partitioning was used to estimate concentrations of dissolved polycyclic aromatic hydrocarbons (PAHs) in the water column from PAH residues in tissues of mussels and juvenile pink salmon collected from coastal marine waters affected by the Exxon Valdez oil spill. Estimated concentrations were within factors of 2 to 5 for fish and 5 to 10 for mussels of average total dissolved and particulate PAHs measured in concurrent water samples. Temporal trends of estimated and measured water-column PAH concentrations were comparable. Water-column PAH concentrations estimated from residues in tissues of mussels (Mytilus trossulus) were higher than estimates based on residues in tissues of juvenile pink salmon (Oncorhynchus gorbuscha). Possible reasons for this difference include seasonal variations in mussel lipid content, differences in PAH uptake and depuration rates between fish and mussels, differences in how fish and mussels interact with particulate oil, and possible short exposure times for juvenile pink salmon. All of these factors may play a role. In any event, estimates of dissolved PAHs in the water column, based on PAH residues in either fish or mussel tissue, confirm that PAH concentrations generally did not exceed water quality standards for protection of marine life

A method for assessing residual NAPL based on organic chemical concentrations in soil samples

International Nuclear Information System (INIS)

Feenstra, S.; Mackay, D.M.; Cherry, J.A.

1991-01-01

Ground water contamination by non-aqueous phase liquid (NAPL) chemicals is a serious concern at many industrial facilities and waste disposal sites. NAPL in the form of immobile residual contamination, or pools of mobile or potentially mobile NAPL, can represent continuing sources of ground water contamination. In order to develop rational and cost-effective plans for remediation of soil and ground water contamination at such sites, it is essential to determine if non-aqueous phase liquid (NAPL) chemicals are present in the subsurface and delineate the zones of NAPL contamination. Qualitatively, soil analyses that exhibit chemical concentrations in the percent range or >10,000 mg/kg would generally be considered to indicate the presence of NAPL. However, the results of soil analyses are seldom used in a quantitative manner to assess the possible presence of residual NAPL contamination when chemical concentrations are lower and the presence of NAPL is not obvious. The assessment of the presence of NAPL in soil samples is possible using the results of chemical and physical analyses of the soil, and the fundamental principles of chemical partitioning in unsaturated or saturated soil. The method requires information on the soil of the type typically considered in ground water contamination studies and provides a simple tool for the investigators of chemical spill and waste disposal sites to assess whether soil chemical analyses indicate the presence of residual NAPL in the subsurface

Effect of Household Coffee Processing on Pesticide Residues as a Means of Ensuring Consumers' Safety.

Science.gov (United States)

Mekonen, Seblework; Ambelu, Argaw; Spanoghe, Pieter

2015-09-30

Coffee is a highly consumed and popular beverage all over the world; however, coffee beans used for daily consumption may contain pesticide residues that may cause adverse health effects to consumers. In this monitoring study, the effect of household coffee processing on pesticide residues in coffee beans was investigated. Twelve pesticides, including metabolites and isomers (endosulfan α, endosulfan β, cypermethrin, permethrin, deltamethrin, chlorpyrifos ethyl, heptachlor epoxide, hexachlorobenzene, p'p-DDE, p'p-DDD, o'p-DDT, and p'p-DDT) were spiked in coffee beans collected from a local market in southwestern Ethiopia. The subsequent household coffee processing conditions (washing, roasting, and brewing) were established as closely as possible to the traditional household coffee processing in Ethiopia. Washing of coffee beans showed 14.63-57.69 percent reduction, while the roasting process reduced up to 99.8 percent. Chlorpyrifos ethyl, permethrin, cypermethrin, endosulfan α and β in roasting and all of the 12 pesticides in the coffee brewing processes were not detected. Kruskal-Wallis analysis indicated that the reduction of pesticide residues by washing is significantly different from roasting and brewing (P coffee roasting and brewing (P > 0.05). The processing factor (PF) was less than one (PF coffee beans. The cumulative effect of the three processing methods has a paramount importance in evaluating the risks associated with ingestion of pesticide residues, particularly in coffee beans.

[Discriminating concentrations for three insecticides used in public health in a Lutzomyia longipalpis experimental strain from Colombia].

Science.gov (United States)

Marceló, Catalina; Cabrera, Olga Lucía; Santamaría, Erika

2014-01-01

In Colombia, periurban populations of Lutzomyia longipalpis , vector of the causative agent of visceral leishmaniasis in the upper and middle valley of the Magdalena River, may be exposed to insecticide applications with different purposes. Thus, it is important to begin a susceptibility surveillance of this species to insecticides. To determine indicators of susceptibility to three insecticides habitually used in public health, such as malathion, deltamethrin and lambda-cyhalothrin in an experimental strain of L. longipalpis . We used the method proposed by the Centers for Disease Control and Prevention. Groups of 10 to 15 unfed females were exposed to different concentrations of the insecticides using 250 ml glass bottles as test chambers. Mortality was registered every five minutes for an hour. Diagnostic concentrations and lethal times for each insecticide were calculated. In the evaluated L. longipalpis strain, the diagnostic concentrations and times were 75 µg/ml and 25 minutes for malathion, 10 µg/ml and 35 minutes for deltamethrin, and 15 µg/ml during 30 minutes for lambda-cyhalothrin. Baseline data over mortality response to three insecticides were established in a susceptibility strain of L. longipalpis vector. These indicators will allow establishing comparisons with populations of L. longipalpis exposed regularly or sporadically to chemical control measures to detect changes in their resistance to these insecticides.

High hole mobility p-type GaN with low residual hydrogen concentration prepared by pulsed sputtering

Science.gov (United States)

Arakawa, Yasuaki; Ueno, Kohei; Kobayashi, Atsushi; Ohta, Jitsuo; Fujioka, Hiroshi

2016-08-01

We have grown Mg-doped GaN films with low residual hydrogen concentration using a low-temperature pulsed sputtering deposition (PSD) process. The growth system is inherently hydrogen-free, allowing us to obtain high-purity Mg-doped GaN films with residual hydrogen concentrations below 5 × 1016 cm-3, which is the detection limit of secondary ion mass spectroscopy. In the Mg profile, no memory effect or serious dopant diffusion was detected. The as-deposited Mg-doped GaN films showed clear p-type conductivity at room temperature (RT) without thermal activation. The GaN film doped with a low concentration of Mg (7.9 × 1017 cm-3) deposited by PSD showed hole mobilities of 34 and 62 cm2 V-1 s-1 at RT and 175 K, respectively, which are as high as those of films grown by a state-of-the-art metal-organic chemical vapor deposition apparatus. These results indicate that PSD is a powerful tool for the fabrication of GaN-based vertical power devices.

Effects of Starvation on Deltamethrin Tolerance in Bed Bugs, Cimex lectularius L. (Hemiptera: Cimicidae

Directory of Open Access Journals (Sweden)

Zachary C. DeVries

2015-01-01

Full Text Available Bed bugs, Cimex lectularius L., are a major pest in the urban environment. Their presence often results in physical, psychological, and financial distress of homeowners and apartment dwellers. Although many insecticide bioassays have been performed on this pest, little attention has been paid to bed bug feeding status, which is closely linked to metabolism, molting, and mass. Therefore, we evaluated the toxicity of topically applied deltamethrin on insecticide susceptible adult male bed bugs fed 2 d, 9 d, and 21 d prior to testing. When toxicity was evaluated on a “per-bug” basis, there was no difference between 2 d [LD50 = 0.498 (0.316 − 0.692 ng·bug−1] and 9 d [LD50 = 0.572 (0.436 − 0.724 ng·bug−1] starved bugs, while 21 d starved bugs had a significantly lower LD50 [0.221 (0.075 − 0.386 ng·bug−1]. When toxicity was evaluated in terms of body mass, 9 d starved bugs had the highest LD50 values [0.138 (0.102 − 0.176 ng·mg−1], followed by 2 d starved bugs [0.095 (0.060 − 0.134 ng·mg−1], and then 21 d starved bugs [0.058 (0.019–0.102 ng·mg−1]; the LD50 values of 2 d and 9 d starved bugs were significantly different from 21 d starved bugs. These results indicate that feeding status plays an important role in the toxicity of deltamethrin. In addition, the lack of differences between 2 d and 9 d starved bugs indicate that the blood meal itself has little impact on tolerance, but rather it is some physiological change following feeding that confers increased tolerance to bed bugs.

Effectiveness of dog collars impregnated with 4% deltamethrin in controlling visceral leishmaniasis in Lutzomyia longipalpis (Diptera: Psychodidade: Phlebotominae) populations.

Science.gov (United States)

Silva, Rafaella Albuquerque E; Andrade, Andrey José de; Quint, Bruno Beust; Raffoul, Gabriel Elias Salmen; Werneck, Guilherme Loureiro; Rangel, Elizabeth Ferreira; Romero, Gustavo Adolfo Sierra

2018-03-26

There is little information on the effect of using deltamethrin-impregnated dog collars for the control of canine visceral leishmaniasis. The objective of this study was to evaluate the effectiveness of the use of 4% deltamethrin-impregnated collars (Scalibor®) in controlling visceral leishmaniasis in Lutzomyia longipalpis by comparing populations in intervention and non-intervention areas. Phlebotomine flies were captured over 30 months in four neighbourhoods with intense visceral leishmaniasis transmission in Fortaleza and Montes Claros. We calculated the rates of domicile infestation, relative abundance of Lu. longipalpis, and Lu. longipalpis distribution in each site, capture location (intra- and peridomestic locations) and area (intervention and non-intervention areas). In the control area in Fortaleza, the relative abundance of Lu. longipalpis was 415 specimens at each capture site, whereas in the intervention area it was 159.25; in Montes Claros, the relative abundance was 5,660 specimens per capture site in the control area, whereas in the intervention area it was 2,499.4. The use of dog collars was associated with a reduction in captured insects of 15% (p = 0.004) and 60% (p < 0.001) in Montes Claros and Fortaleza, respectively. We observed a lower vector abundance in the intervention areas, suggesting an effect of the insecticide-impregnated collars.

Concentrations and dissipation of difenoconazole and fluxapyroxad residues in apples and soil, determined by ultrahigh-performance liquid chromatography electrospray ionization tandem mass spectrometry.

Science.gov (United States)

He, Min; Jia, Chunhong; Zhao, Ercheng; Chen, Li; Yu, Pingzhong; Jing, Junjie; Zheng, Yongquan

2016-03-01

A new combined difenoconazole and fluxapyroxad fungicide formulation, as an 11.7 % suspension concentrate (SC), has been introduced as part of a resistance management strategy. The dissipation of difenoconazole and fluxapyroxad applied to apples and the residues remaining in the apples were determined. The 11.7 % SC was sprayed onto apple trees and soil in Beijing, Shandong, and Anhui provinces, China, at an application rate of 118 g a.i. ha(-1), then the dissipation of difenoconazole and fluxapyroxad was monitored. The residual difenoconazole and fluxapyroxad concentrations were determined by ultrahigh-performance liquid chromatography tandem mass spectrometry. The difenoconazole half-lives in apples and soil were 6.2-9.5 and 21.0-27.7 days, respectively. The fluxapyroxad half-lives in apples and soil were 9.4-12.6 and 10.3-36.5 days, respectively. Difenoconazole and fluxapyroxad residues in apples and soil after the 11.7 % SC had been sprayed twice and three times, with 10 days between applications, at 78 and 118 g a.i. ha(-1) were measured. Representative apple and soil samples were collected after the last treatment, at preharvest intervals of 14, 21, and 28 days. The difenoconazole residue concentrations in apples and soil were 0.002-0.052 and 0.002-0.298 mg kg(-1), respectively. The fluxapyroxad residue concentrations in apples and soil were 0.002-0.093 and 0.008-1.219 mg kg(-1), respectively. The difenoconazole and fluxapyroxad residue concentrations in apples were lower than the maximum residue limits (0.5 and 0.8 mg kg(-1), respectively). An application rate of 78 g a.i. ha(-1) is therefore recommended to ensure that treated apples can be considered safe for humans to consume.

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

Science.gov (United States)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-02-01

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) & 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) &29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

International Nuclear Information System (INIS)

AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman

2014-01-01

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232 Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted

Thorium, Uranium and Rare Earth Elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas Advanced Materials Plant (LAMP)

International Nuclear Information System (INIS)

Al-Areqi, W.M.; Amran Abdul Majid; Sukiman Sarmani

2013-01-01

Full-text: Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6 Bq/ kg) whereas the Th and U concentrations in WLP were determined to be 1952.9 ± 17.6 ppm (7987.4 ± 71.9 Bq/ kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/ kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/ kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of 232 Th compared to Malaysian soil natural background (63 - 110 Bq/ kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6 % and 4.7 ± 0.1 % respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04 %, 1.6 %, 0.22 % and 0.06 % respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be re

Thorium, uranium and rare earth elements content in lanthanide concentrate (LC) and water leach purification (WLP) residue of Lynas advanced materials plant (LAMP)

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AL-Areqi, Wadeeah M., E-mail: walareqi@yahoo.com; Majid, Amran Ab., E-mail: walareqi@yahoo.com; Sarmani, Sukiman, E-mail: walareqi@yahoo.com [Nuclear Science Programme, School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi (Malaysia)

2014-02-12

Lynas Advanced Materials Plant (LAMP) has been licensed to produce the rare earths elements since early 2013 in Malaysia. LAMP processes lanthanide concentrate (LC) to extract rare earth elements and subsequently produce large volumes of water leach purification (WLP) residue containing naturally occurring radioactive material (NORM). This residue has been rising up the environmental issue because it was suspected to accumulate thorium with significant activity concentration and has been classified as radioactive residue. The aim of this study is to determine Th-232, U-238 and rare earth elements in lanthanide concentrate (LC) and water leach purification (WLP) residue collected from LAMP and to evaluate the potential radiological impacts of the WLP residue on the environment. Instrumental Neutron Activation Analysis and γ-spectrometry were used for determination of Th, U and rare earth elements concentrations. The results of this study found that the concentration of Th in LC was 1289.7 ± 129 ppm (5274.9 ± 527.6Bq/kg) whereas the Th and U concentrations in WLP were determined to be 1952.9±17.6 ppm (7987.4 ± 71.9 Bq/kg) and 17.2 ± 2.4 ppm respectively. The concentrations of Th and U in LC and WLP samples determined by γ- spectrometry were 1156 ppm (4728 ± 22 Bq/kg) and 18.8 ppm and 1763.2 ppm (7211.4 Bq/kg) and 29.97 ppm respectively. This study showed that thorium concentrations were higher in WLP compare to LC. This study also indicate that WLP residue has high radioactivity of {sup 232}Th compared to Malaysian soil natural background (63 - 110 Bq/kg) and come under preview of Act 304 and regulations. In LC, the Ce and Nd concentrations determined by INAA were 13.2 ± 0.6% and 4.7 ± 0.1% respectively whereas the concentrations of La, Ce, Nd and Sm in WLP were 0.36 ± 0.04%, 1.6%, 0.22% and 0.06% respectively. This result showed that some amount of rare earth had not been extracted and remained in the WLP and may be considered to be reextracted.

EVALUATION OF FERRIC CHLORIDE AND ALUM EFFICIENCIES IN ENHANCED COAGULATION FOR TOC REMOVAL AND RELATED RESIDUAL METAL CONCENTRATIONS

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A. Mesdaghinia, M. T. Rafiee, F. Vaezi and A. H. Mahvi

2005-07-01

Full Text Available Although the removal of colloidal particles continues to be an important reason for using coagulation, a newer objective, the removal of natural organic matter (NOM to reduce the formation of disinfection by-products (DBPs, is growing in importance. Enhanced coagulation is thus introduced to most water utilities treating surface water. Bench-scale experiments were conducted to compare the effectiveness of alum and ferric chloride in removing DBPs precursors from eight synthetic water samples, each representing a different element of the USEPA’s 3×3 enhanced coagulation matrix. The effect of enhanced coagulation on the residual metal (aluminum/iron concentration in the treated water was assessed as well. The removal of total organic carbon (TOC was dependent on the coagulant type and was enhanced with increasing coagulant dose, but the latter had no further considerable effect in case of increasing to high levels. For all the treated samples coagulation with ferric chloride proved to be more effective than alum at similar doses and the mean values of treatment efficiencies were 51% and 32% for ferric chloride and alum, respectively. Ferric chloride was therefore considered the better chemical for enhancing the coagulation process. Besides, due to less production of sludge by this coagulant, it would be predicted that treatment plants would be confronted to fewer problems with respect to final sludge disposal. Measurements of residual metal in treated water indicated that iron and aluminum concentrations had been increased as expected but the quality of water concerning the residual metal deteriorated much more in cases of under-dosing. Despite expecting high residual Al and Fe concentrations under enhanced coagulation, metal concentrations were frequently remained low and were not increased appreciably.

Access to residual carrier concentration in ZnO nanowires by calibrated scanning spreading resistance microscopy

Energy Technology Data Exchange (ETDEWEB)

Wang, L., E-mail: lin.wang@insa-lyon.fr; Brémond, G. [Institut des Nanotechnologies de Lyon (INL), Université de Lyon, CNRS UMR 5270, INSA Lyon, Bat. Blaise Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne (France); Chauveau, J. M. [Centre de Recherche sur l' Hétéro-Epitaxie et ses Applications (CRHEA), CNRS UPR10, rue Bernard Grégory 06560 Valbonne Sophia Antipolis (France); Physics Department, University of Nice Sophia Antipolis (UNS), Parc Valrose, 06103 Nice (France); Brenier, R. [Institut Lumière Matière (ILM), Université de Lyon, CNRS UMR 5306, Université Claude Bernard Lyon 1, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne (France); Sallet, V.; Jomard, F.; Sartel, C. [Groupe d' Étude de la Matière Condensée (GEMaC), CNRS-Université de Versailles St Quentin en Yvelines, Université Paris-Saclay, 45 Avenue des Etats-Unis, 78035 Versailles (France)

2016-03-28

Scanning spreading resistance microscopy (SSRM) was performed on non-intentionally doped (nid) ZnO nanowires (NWs) grown by metal-organic chemical vapor deposition in order to measure their residual carrier concentration. For this purpose, an SSRM calibration profile has been developed on homoepitaxial ZnO:Ga multilayer staircase structures grown by molecular beam epitaxy. The Ga density measured by SIMS varies in the 1.7 × 10{sup 17 }cm{sup −3} to 3 × 10{sup 20 }cm{sup −3} range. From measurements on such Ga doped multi-layers, a monotonic decrease in SSRM resistance with increasing Ga density was established, indicating SSRM being a well-adapted technique for two dimensional dopant/carrier profiling on ZnO at nanoscale. Finally, relevant SSRM signal contrasts were detected on nid ZnO NWs, and the residual carrier concentration is estimated in the 1–3 × 10{sup 18 }cm{sup −3} range, in agreement with the result from four-probe measurements.

Evaluation of deltamethrin kinetics and dosimetry in the maturing rat using a PBPK model

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Tornero-Velez, Rogelio; Mirfazaelian, Ahmad; Kim, Kyu-Bong; Anand, Sathanandam S.; Kim, Hyo J.; Haines, Wendy T.; Bruckner, James V.; Fisher, Jeffrey W.

2010-01-01

Immature rats are more susceptible than adults to the acute neurotoxicity of pyrethroid insecticides like deltamethrin (DLM). A companion kinetics study (Kim et al., in press) revealed that blood and brain levels of the neuroactive parent compound were inversely related to age in rats 10, 21, 40 and 90 days old. The objective of the current study was to modify a physiologically based pharmacokinetic (PBPK) model of DLM disposition in the adult male Sprague-Dawley rat (Mirfazaelian et al., 2006), so blood and target organ dosimetry could be accurately predicted during maturation. Age-specific organ weights and age-dependent changes in the oxidative and hydrolytic clearance of DLM were modeled with a generalized Michaelis-Menten model for growth and the summary equations incorporated into the PBPK model. The model's simulations compared favorably with empirical DLM time-courses in plasma, blood, brain and fat for the four age-groups evaluated (10, 21, 40 and 90 days old). PND 10 pups' area under the 24-h brain concentration time curve (AUC 0-24h ) was 3.8-fold higher than that of the PND 90 adults. Our maturing rat PBPK model allows for updating with age- and chemical-dependent parameters, so pyrethroid dosimetry can be forecast in young and aged individuals. Hence, this model provides a methodology for risk assessors to consider age-specific adjustments to oral Reference Doses on the basis of PK differences.

Optimization of elution salt concentration in stepwise elution of protein chromatography using linear gradient elution data. Reducing residual protein A by cation-exchange chromatography in monoclonal antibody purification.

Science.gov (United States)

Ishihara, Takashi; Kadoya, Toshihiko; Endo, Naomi; Yamamoto, Shuichi

2006-05-05

Our simple method for optimization of the elution salt concentration in stepwise elution was applied to the actual protein separation system, which involves several difficulties such as detection of the target. As a model separation system, reducing residual protein A by cation-exchange chromatography in human monoclonal antibody (hMab) purification was chosen. We carried out linear gradient elution experiments and obtained the data for the peak salt concentration of hMab and residual protein A, respectively. An enzyme-linked immunosorbent assay was applied to the measurement of the residual protein A. From these data, we calculated the distribution coefficient of the hMab and the residual protein A as a function of salt concentration. The optimal salt concentration of stepwise elution to reduce the residual protein A from the hMab was determined based on the relationship between the distribution coefficient and the salt concentration. Using the optimized condition, we successfully performed the separation, resulting in high recovery of hMab and the elimination of residual protein A.

Environmentally relevant pyrethroid mixtures: A study on the correlation of blood and brain concentrations of a mixture of pyrethroid insecticides to motor activity in the rat.

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Hughes, Michael F; Ross, David G; Starr, James M; Scollon, Edward J; Wolansky, Marcelo J; Crofton, Kevin M; DeVito, Michael J

2016-06-01

Human exposure to multiple pyrethroid insecticides may occur because of their broad use on crops and for residential pest control. To address the potential health risk from co-exposure to pyrethroids, it is important to understand their disposition and toxicity in target organs such as the brain, and surrogates such as the blood when administered as a mixture. The objective of this study was to assess the correlation between blood and brain concentrations of pyrethroids and neurobehavioral effects in the rat following an acute oral administration of the pyrethroids as a mixture. Male Long-Evans rats were administered a mixture of β-cyfluthrin, cypermethrin, deltamethrin, esfenvalerate and cis- and trans-permethrin in corn oil at seven dose levels. The pyrethroid with the highest percentage in the dosing solution was trans-permethrin (31% of total mixture dose) while deltamethrin and esfenvalerate had the lowest percentage (3%). Motor activity of the rats was then monitored for 1h. At 3.5h post-dosing, the animals were euthanized and blood and brain were collected. These tissues were extracted and analyzed for parent pyrethroid using HPLC-tandem mass spectrometry. Cypermethrin and cis-permethrin were the predominate pyrethroids detected in blood and brain, respectively, at all dosage levels. The relationship of total pyrethroid concentration between blood and brain was linear (r=0.93). The pyrethroids with the lowest fraction in blood were trans-permethrin and β-cyfluthrin and in brain were deltamethrin and esfenvalerate. The relationship between motor activity of the treated rats and summed pyrethroid blood and brain concentration was described using a sigmoidal Emax model with the Effective Concentration50 being more sensitive for brain than blood. The data suggests summed pyrethroid rat blood concentration could be used as a surrogate for brain concentration as an aid to study the neurotoxic effects of pyrethroids administered as a mixture under the conditions

Variation in susceptibility of laboratory and field strains of three stored-grain insect species to beta-cyfluthrin and chlorpyrifos-methyl plus deltamethrin applied to concrete surfaces

Science.gov (United States)

The efficacy of beta-cyfluthrin and chlorpyrifos-methyl plus deltamethrin applied to clean, concrete floors of empty bins prior to grain storage against field strains of stored-grain insects is unknown. We exposed adults of 16 strains of the red flour beetle, Tribolium castaneum (Herbst); 8 strains ...

Optimization of the protein concentration process from residual peanut oil-cake

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Gayol, M. F.

2013-12-01

Full Text Available The objective of this study was to find the best process conditions for preparing protein concentrate from residual peanut oil-cake (POC. The study was carried out on POC from industrial peanut oil extraction. Different protein extraction and precipitation conditions were used: water/ flour ratio (10:1, 20:1 and 30:1, pH (8, 9 and 10, NaCl concentration (0 and 0.5 M, extraction time (30, 60 and 120 min, temperature (25, 40 and 60 °C, extraction stages (1, 2 and 3, and precipitation pH (4, 4.5 and 5. The extraction and precipitation conditions which showed the highest protein yield were 10:1 water/flour ratio, extraction at pH 9, no NaCl, 2 extraction stages of 30 min at 40 °C and precipitation at pH 4.5. Under these conditions, the peanut protein concentrate (PC contained 86.22% protein, while the initial POC had 38.04% . POC is an alternative source of protein that can be used for human consumption or animal nutrition. Therefore, it adds value to an industry residue.El objetivo de este trabajo fue encontrar las mejores condiciones para obtener un concentrado de proteínas a partir de la torta residual de maní (POC. El estudio se llevó a cabo en POC provenientes de la extracción industrial de aceite de maní. Se utilizaron distintas condiciones para la extracción y precipitación de proteínas: relación agua / harina (10:1, 20:1 y 30:1, pH de extracción (8, 9 y 10, concentración de NaCl (0 y 0,5 M, tiempo de extracción (30, 60 y 120 min, temperatura (25, 40 y 60 °C, número de etapas de extracción (1, 2 y 3, y el pH de precipitación (4, 4,5 y 5. Las condiciones de extracción y de precipitación que mostraron mayor rendimiento de proteína fueron: relación de 10:1 en agua / harina, pH de extracción de 9, en ausencia de NaCl, 2 etapas de extracción de 30 min cada una a 40 °C y el pH de precipitación de 4,5. En estas condiciones, el concentrado de proteína de maní (PC fue de 86,22%, mientras que el porcentaje de proteínas de

Protective effects of L-glutamine against toxicity of deltamethrin in the cerebral tissue

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Varol S

2016-04-01

Full Text Available Sefer Varol, Hasan Hüseyin Özdemir, Mehmet Uğur Çevik, Yaşar Altun, Ibrahim Ibiloğlu, Aysun Ekinci, Aslıhan Okan Ibiloğlu, Metin Balduz, Demet Arslan, Recep Tekin, Fesih Aktar, Mehmet Ufuk Aluçlu Department of Neurology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey Background: Deltamethrin (DLM is a broad-spectrum synthetic dibromo-pyrethroid pesticide that is widely used for agricultural and veterinary purposes. However, human exposure to the pesticide leads to neurotoxicity. Glutamine is one of the principal, free intracellular amino acids and may also be an antioxidant. This study was undertaken in order to examine the neuroprotective and antioxidant potential of L-glutamine against DLM toxicity in female Wistar albino rats. Materials and methods: The rats were divided into the following groups (n=10: Group I: control (distilled water; 10 mL/kg, po one dose, Group II: L-glutamine (1.5 g/kg, po one dose, Group III: DLM (35 mg/kg, po one dose, and Group IV: DLM (35 mg/kg, po one dose and L-glutamine (1.5 g/kg, po one dose after 4 hours. Total oxidant status (TOS, total antioxidant status (TAS, tumor necrosis factor-α, interleukin (IL-1β, and IL-6 levels and apoptosis were evaluated in brain tissue. Results: DLM-treated animals had a significant increase in brain biochemical parameters, as well as TOS and TAS. Furthermore, the histopathological examination showed neuronal cell degeneration in the cerebral tissue. L-Glutamine treatment decreased the elevated brain levels of TOS and neuronal cell degeneration. There was no difference in tumor necrosis factor-α, IL-1β, and IL-6 levels between the groups. Conclusion: L-Glutamine may reduce the toxic effects of DLM in the cerebral tissue through antioxidant properties. Keywords: deltamethrin, L-glutamine, rat

Overexpression of multiple detoxification genes in deltamethrin resistant Laodelphax striatellus (Hemiptera: Delphacidae in China.

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Lu Xu

Full Text Available BACKGROUND: The small brown planthopper (SBPH, Laodelphax striatellus (Fallén, is one of the major rice pests in Asia and has developed resistance to multiple classes of insecticides. Understanding resistance mechanisms is essential to the management of this pest. Biochemical and molecular assays were performed in this study to systematically characterize deltamethrin resistance mechanisms with laboratory-selected resistant and susceptible strains of SBPH. METHODOLOGY/PRINCIPAL FINDINGS: Deltamethrin resistant strains of SBPH (JH-del were derived from a field population by continuously selections (up to 30 generations in the laboratory, while a susceptible strain (JHS was obtained from the same population by removing insecticide pressure for 30 generations. The role of detoxification enzymes in the resistance was investigated using synergism and enzyme activity assays with strains of different resistant levels. Furthermore, 71 cytochrome P450, 93 esterases and 12 glutathione-S-transferases cDNAs were cloned based on transcriptome data of a field collected population. Semi-quantitative RT-PCR screening analysis of 176 identified detoxification genes demonstrated that multiple P450 and esterase genes were overexpressed (>2-fold in JH-del strains (G4 and G30 when compared to that in JHS, and the results of quantitative PCR coincided with the semi-quantitative RT-PCR results. Target mutation at IIS3-IIS6 regions encoded by the voltage-gated sodium channel gene was ruled out for conferring the observed resistance. CONCLUSION/SIGNIFICANCE: As the first attempt to discover genes potentially involved in SBPH pyrethroid resistance, this study putatively identified several candidate genes of detoxification enzymes that were significantly overexpressed in the resistant strain, which matched the synergism and enzyme activity testing. The biochemical and molecular evidences suggest that the high level pyrethroid resistance in L. striatellus could be due to

Rapid detection of chlorpyrifos pesticide residue concentration in agro-product using Raman spectroscopy

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Dhakal, Sagar; Peng, Yankun; Li, Yongyu; Chao, Kuanglin; Qin, Jianwei; Zhang, Leilei; Xu, Tianfeng

2014-05-01

Different chemicals are sprayed in fruits and vegetables before and after harvest for better yield and longer shelf-life of crops. Cases of pesticide poisoning to human health are regularly reported due to excessive application of such chemicals for greater economic benefit. Different analytical technologies exist to detect trace amount of pesticides in fruits and vegetables, but are expensive, sample destructive, and require longer processing time. This study explores the application of Raman spectroscopy for rapid and non-destructive detection of pesticide residue in agricultural products. Raman spectroscopy with laser module of 785 nm was used to collect Raman spectral information from the surface of Gala apples contaminated with different concentrations of commercially available organophosphorous (48% chlorpyrifos) pesticide. Apples within 15 days of harvest from same orchard were used in this study. The Raman spectral signal was processed by Savitzky-Golay (SG) filter for noise removal, Multiplicative Scatter Correction (MSC) for drift removal and finally polynomial fitting was used to eliminate the fluorescence background. The Raman spectral peak at 677 cm-1 was recognized as Raman fingerprint of chlorpyrifos. Presence of Raman peak at 677 cm-1 after fluorescence background removal was used to develop classification model (presence and absence of pesticide). The peak intensity was correlated with actual pesticide concentration obtained using Gas Chromatography and MLR prediction model was developed with correlation coefficient of calibration and validation of 0.86 and 0.81 respectively. Result shows that Raman spectroscopy is a promising tool for rapid, real-time and non-destructive detection of pesticide residue in agro-products.

Evaluation of the effects of repeated hand washing, sunlight, smoke and dirt on the persistence of deltamethrin on insecticide-treated nets.

Science.gov (United States)

Kayedi, M H; Lines, J D; Haghdoost, A A; Vatandoost, M H; Rassi, Y; Khamisabady, K

2008-08-01

Field studies were carried out in Iran to evaluate the effect of various factors (washing, sun, smoke, dust and dirt) on the residual insecticidal activity of PermaNet (a brand of long-lasting insecticidal net), and on nets conventionally treated with deltamethrin (K-O Tab), using bioassay tests. Thirty-two nets were washed five or 15 times, and eight nets were not washed at all. Nets were washed vigorously in cold tap water (17 degrees C, pH 8.9) with a detergent. Hand rubbing continued for 3min. After washing, some nets were exposed to dense smoke from a dung-hay fire for 3min and were also left exposed to the dusty wind between washes. One group of nets was exposed to the sunlight for the full 3-d interval between washes; another was exposed to sunlight for just 3h after each wash; two other groups were kept in the shade. There was a significantly greater loss of activity in nets exposed to the sun throughout the 3-d interval between washes: that is, for a total of 15 to 45 d. However, short sunlight exposure (maximum 3h between washes) during drying did not have any effect. We did not find any significant effect of exposure to dirt, dust and smoke after washing. It is concluded that the effect of sun is much smaller than that of washing, and that drying nets for a few hours in the sun is not harmful.

Comparison of questionnaire-based estimation of pesticide residue intake from fruits and vegetables with urinary concentrations of pesticide biomarkers.

Science.gov (United States)

Chiu, Yu-Han; Williams, Paige L; Mínguez-Alarcón, Lidia; Gillman, Matthew; Sun, Qi; Ospina, Maria; Calafat, Antonia M; Hauser, Russ; Chavarro, Jorge E

2018-01-01

We developed a pesticide residue burden score (PRBS) based on a food frequency questionnaire and surveillance data on food pesticide residues to characterize dietary exposure over the past year. In the present study, we evaluated the association of the PRBS with urinary concentrations of pesticide biomarkers. Fruit and vegetable (FV) intake was classified as having high (PRBS≥4) or low (PRBSEARTH study. Two urine samples per man were analyzed for seven biomarkers of organophosphate and pyrethroid insecticides, and the herbicide 2,4-dichlorophenoxyacetic acid. We used generalized estimating equations to analyze the association of the PRBS with urinary concentrations of pesticide biomarkers. Urinary concentrations of pesticide biomarkers were positively related to high pesticide FV intake but inversely related to low pesticide FV intake. The molar sum of urinary concentrations of pesticide biomarkers was 21% (95% confidence interval (CI): 2%, 44%) higher for each one serving/day increase in high pesticide FV intake, and 10% (95% CI: 1%, 18%) lower for each one serving/day increase in low pesticide FV intake. Furthermore, intake of high pesticide FVs positively related to most individual urinary biomarkers. Our findings support the usefulness of the PRBS approach to characterize dietary exposure to select pesticides.

Effectiveness of control strategies against Botrytis cinerea in vineyard and evaluation of the residual fungicide concentrations.

Science.gov (United States)

Gabriolotto, Chiara; Monchiero, Matteo; Negre, Michele; Spadaro, Davide; Gullino, Maria Lodovica

2009-05-01

This investigation was undertaken to test different control strategies against Botrytis cinerea vineyards. Two commercial vineyards, "Barbera" and "Moscato," located in Piedmont (Northern Italy) were divided into seven plots and treated with different combinations of fungicides including fenhexamid, pyrimethanil, fludioxonil + cyprodinil, iprodione, and boscalid, a new carboxamide compound. An integrated strategy including a chemical (pyrimethanil) and a biocontrol agent (Trichoderma spp. t2/4ph1) was also included. At harvest, the percentage of bunches and berries attacked by B. cinerea and the concentration of the chemical fungicides were determined. All the pesticide residues at harvest were below the maximum residue level (MRL), except when two applications of pyrimethanil per season were applied. Boscalid was the most effective active ingredient against B. cinerea among the tested chemicals. When boscalid application was followed by a treatment with pyrimethanil, its efficacy was similar to that shown by two treatments of pyrimethanil. However, this second strategy was not feasible due to the risks of resistance development in the pathogen and to the residue accumulation as indicated by the analysis.

Contact toxicity and residual effects of selected insecticides against the adult Paederus fuscipes (Coleoptera: Staphylinidae).

Science.gov (United States)

Bong, Lee-Jin; Neoh, Kok-Boon; Jaal, Zairi; Lee, Chow-Yang

2013-12-01

The contact toxicity of four insecticide formulations (deltamethrin, fipronil, fenitrothion, and imidacloprid) applied on three different substrates (tile, plywood, and concrete) against the adult rove beetle, Paederus fuscipes Curtis, was evaluated. The relative order of speed of killing effects was as follows: deltamethrin > imidacloprid > fipronil > fenitrothion. Although deltamethrin showed the fastest action against P. fuscipes, the recovery rate of rove beetles at 48 h posttreatment was moderate (approximately 25%) on the tile surface to high (approximately 80%) on the plywood surface. Thus, it is likely that the insects did not pick up the lethal dose especially on porous surfaces. In contrast, fipronil demonstrated delayed toxicity that might promote maximal uptake by the insects. More than 80% mortality was registered for tile and plywood surfaces up to 4 wk after exposure. High mortality (almost 100%) was recorded for imidacloprid-exposed P. fuscipes at 48 h posttreatment, but only on the tile surface. Among the four insecticides tested, fenitrothion was the least effective against P. fuscipes because low percentage to no mortality was recorded in the fenitrothion treatment.

Food safety in Thailand 2: Pesticide residues found in Chinese kale (Brassica oleracea), a commonly consumed vegetable in Asian countries

International Nuclear Information System (INIS)

Wanwimolruk, Sompon; Kanchanamayoon, Onnicha; Phopin, Kamonrat; Prachayasittikul, Virapong

2015-01-01

There is increasing public concern over human health risks associated with extensive use of pesticides in agriculture. Regulation of pesticide maximum residue limits (MRLs) in food commodities is established in many developed countries. For Thailand, this regulation exists in law but is not fully enforced. Therefore, pesticide residues in vegetables and fruits have not been well monitored. This study investigated the pesticide residues in Chinese kale, a commonly eaten vegetable among Asians. The Chinese kale samples (N = 117) were purchased from markets in Nakhon Pathom Province, Thailand, and analyzed for the content of 28 pesticides. Analysis was performed by the multiresidual extraction followed by GC–MS/MS. Of pesticides investigated, 12 pesticides were detected in 85% of the Chinese kale samples. Although carbaryl, deltamethrin, diazinon, fenvalerate and malathion were found in some samples, their levels were lower than their MRLs. However, in 34 samples tested, either carbofuran, chlorpyrifos, chlorothalonil, cypermethrin, dimethoate, metalaxyl or profenofos was detected exceeding their MRLs. This represents a 29% rate of pesticide detection above the MRL; a rate much higher than in developed countries. Washing vegetables under running water significantly reduced (p < 0.05) profenofos residues by 55%. The running water method did not significantly decrease cypermethrin residues in the samples but washing with vinegar did. Our research suggests that routine monitoring of pesticide residues is necessary to reduce the public health risks associated with eating contaminated vegetables. Washing vegetables before consumption is advisable as this helps to reduce the level of pesticide residues in our daily intake. - Highlights: • Significant pesticide residues were detected in Chinese kale sold in Thailand. • MRL exceedance was found and this was higher than that seen in developed countries. • Washing vegetables under running water can remove pesticide

Food safety in Thailand 2: Pesticide residues found in Chinese kale (Brassica oleracea), a commonly consumed vegetable in Asian countries

Energy Technology Data Exchange (ETDEWEB)

Wanwimolruk, Sompon, E-mail: sompon-999@hotmail.com [Center for Innovation Development and Technology Transfer, Faculty of Medical Technology, Mahidol University, Bangkok 10700 (Thailand); Kanchanamayoon, Onnicha [Center for Innovation Development and Technology Transfer, Faculty of Medical Technology, Mahidol University, Bangkok 10700 (Thailand); Phopin, Kamonrat [Center for Innovation Development and Technology Transfer, Faculty of Medical Technology, Mahidol University, Bangkok 10700 (Thailand); Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok 10700 (Thailand); Prachayasittikul, Virapong [Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok 10700 (Thailand)

2015-11-01

There is increasing public concern over human health risks associated with extensive use of pesticides in agriculture. Regulation of pesticide maximum residue limits (MRLs) in food commodities is established in many developed countries. For Thailand, this regulation exists in law but is not fully enforced. Therefore, pesticide residues in vegetables and fruits have not been well monitored. This study investigated the pesticide residues in Chinese kale, a commonly eaten vegetable among Asians. The Chinese kale samples (N = 117) were purchased from markets in Nakhon Pathom Province, Thailand, and analyzed for the content of 28 pesticides. Analysis was performed by the multiresidual extraction followed by GC–MS/MS. Of pesticides investigated, 12 pesticides were detected in 85% of the Chinese kale samples. Although carbaryl, deltamethrin, diazinon, fenvalerate and malathion were found in some samples, their levels were lower than their MRLs. However, in 34 samples tested, either carbofuran, chlorpyrifos, chlorothalonil, cypermethrin, dimethoate, metalaxyl or profenofos was detected exceeding their MRLs. This represents a 29% rate of pesticide detection above the MRL; a rate much higher than in developed countries. Washing vegetables under running water significantly reduced (p < 0.05) profenofos residues by 55%. The running water method did not significantly decrease cypermethrin residues in the samples but washing with vinegar did. Our research suggests that routine monitoring of pesticide residues is necessary to reduce the public health risks associated with eating contaminated vegetables. Washing vegetables before consumption is advisable as this helps to reduce the level of pesticide residues in our daily intake. - Highlights: • Significant pesticide residues were detected in Chinese kale sold in Thailand. • MRL exceedance was found and this was higher than that seen in developed countries. • Washing vegetables under running water can remove pesticide

Variations of insecticide residual bio-efficacy on different types of walls: results from a community-based trial in south Cameroon

Directory of Open Access Journals (Sweden)

Etang Josiane

2011-11-01

Full Text Available Abstract Background Determination of residual activity of insecticides is essential information for the selection of appropriate indoor spraying operation. The present study was undertaken to evaluate the residual effect of three candidate insecticide formulations on different indoor surfaces in order to guide future interventions, in the context of Cameroon and other African countries. Methods The study was conducted in the Ntougou neighbourhood in Yaoundé (capital city of Cameroon. Bendiocarb WP, lambda-cyhalothrin CS and deltamethrin WG were sprayed on the indoor wall surfaces of local cement, wood and mud houses. Their effects on the knockdown and mortality of the Kisumu susceptible strain of Anopheles gambiae s.s were assessed each month from March to September 2009, using the WHO plastic cones test. Knockdown and mortality rates were compared between different surfaces using Chi-square test. A Kaplan-Meir model was used to estimate the time of treatment failure. Results With bendiocarb WP, the knockdown rates were frequently above 98% during 13 weeks after spraying, except on mud walls where it significantly decreased at the 13th week (P th (83% and the 20th (88% weeks respectively (P 98%; while it varied between 60 and 100% on wood or mud surfaces. The survival estimates of bendiocarb WP treatments remaining effective in killing An. gambiae s.s. (mortality rate ≥ 80% was > 13 weeks on cement and wood surfaces and 13 weeks on mud surfaces. Those of lambda-cyhalothrin CS were > 26 weeks on wood surfaces, and 20 weeks on concrete and mud surfaces. By contrast, those of deltamethrin WG were 26 weeks on concrete, 20 weeks on mud surfaces and 15 weeks on wood surfaces. Conclusion Current data suggest variable durations of spray cycles for each product, according to the type of wall surfaces, highlighting the importance of testing candidate products in local context before using them in large scale.

Laboratory investigations of insecticide impregnated materials for the control of New World screwworm flies

International Nuclear Information System (INIS)

Harris, E.G.; Brown, M.; Smith, S.

1992-01-01

In laboratory tests, New World screwworm flies were found to be at least three orders of magnitude less susceptible to the insecticides deltamethrin, alphacypermethrin and cyfluthrin than are tsetse flies. Deltamethrin was the most toxic of the three insecticides to screwworm flies. For topical application, the LD50s for deltamethrin 20% suspension concentrate were 33 ng and 25 ng for male and female screwworm flies respectively, compared with 0.04 ng for tsetse, G.m. morsitans. In various tests simulating contact of screwworm flies with cloth or netting targets impregnated with insecticide, 100% kill was only achieved with 3.2% deltamethrin and contact times of at least 10 sec, although 100% knockdown for up to 24 hours was obtained with lower concentrations. No repellent effect was observed at the higher concentrations. Cloth targets impregnated with a high dose of insecticide and baited with an attractant could be effective against NWS flies, especially if after ''knockdown'' flies are removed by predators. 1 fig., 9 tabs

Radiological Modeling for Determination of Derived Concentration Levels of an Area with Uranium Residual Material - 13533

Energy Technology Data Exchange (ETDEWEB)

Perez-Sanchez, Danyl [CIEMAT, Avenida Complutense 40, 28040, Madrid (Spain)

2013-07-01

As a result of a pilot project developed at the old Spanish 'Junta de Energia Nuclear' to extract uranium from ores, tailings materials were generated. Most of these residual materials were sent back to different uranium mines, but a small amount of it was mixed with conventional building materials and deposited near the old plant until the surrounding ground was flattened. The affected land is included in an area under institutional control and used as recreational area. At the time of processing, uranium isotopes were separated but other radionuclides of the uranium decay series as Th-230, Ra-226 and daughters remain in the residue. Recently, the analyses of samples taken at different ground's depths confirmed their presence. This paper presents the methodology used to calculate the derived concentration level to ensure that the reference dose level of 0.1 mSv y-1 used as radiological criteria. In this study, a radiological impact assessment was performed modeling the area as recreational scenario. The modelization study was carried out with the code RESRAD considering as exposure pathways, external irradiation, inadvertent ingestion of soil, inhalation of resuspended particles, and inhalation of radon (Rn-222). As result was concluded that, if the concentration of Ra-226 in the first 15 cm of soil is lower than, 0.34 Bq g{sup -1}, the dose would not exceed the reference dose. Applying this value as a derived concentration level and comparing with the results of measurements on the ground, some areas with a concentration of activity slightly higher than latter were found. In these zones the remediation proposal has been to cover with a layer of 15 cm of clean material. This action represents a reduction of 85% of the dose and ensures compliance with the reference dose. (authors)

Toxicidade residual de alguns agrotóxicos recomendado na agricultura sobre Neoseiulus californicus (McGregor (Acari: Phytoseiidae Residual toxicity of some pesticides recommended for citrus orchards on the predaceous mite Neoseiulus californicus (McGregor (Acari: phytoseiidae

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Marcos Zatti da Silva

2007-04-01

Full Text Available O objetivo do trabalho foi avaliar a toxicidade residual de alguns agrotóxicos utilizados em citros sobre Neoseiulus californicus (McGregor em condições de laboratório. O método de bioensaio adotado foi o de contato residual. Folhas de citros da variedade Pêra, acondicionadas em arenas, foram pulverizadas em torre de Potter. A toxicidade residual dos produtos foi avaliada duas horas e 1; 3; 5; 7; 10; 14 e 21 dias após a aplicação. Em cada arena, foram transferidas dez fêmeas adultas de N. californicus, juntamente com uma quantidade suficiente de Tetranychus urticae, como fonte de alimento. As avaliações de mortalidade foram realizadas 72 horas após a transferência dos ácaros para as arenas. Os agrotóxicos acrinathrin, deltamethrin, dinocap, enxofre, fenpropathrin, óxido de fenbutatin e propargite não causaram mortalidades significativas em adultos de N. californicus. Foram registradas mortalidades de 29,8; 24,0 e 34,1% para ácaros N. californicus expostos a resíduos de duas horas de idade de abamectim, azocyclotin e cyhexatin, respectivamente. Dicofol, pyridaben e chlorfenapyr causaram 100% de mortalidade aos ácaros predadores expostos aos resíduos tóxicos dos acaricidas, com duas horas de idade. Abamectin provocou mortalidade significativa por um período inferior a um dia. Resíduos dos acaricidas azocyclotin, cyhexatin, dicofol, pyridaben e chlorfenapyr provocaram mortalidades significativas por períodos de 1; 1; 10; 10 e 21dias, respectivamente. Os resultados obtidos no presente experimento servem de subsídio para a escolha adequada dos agrotóxicos a serem utilizados em pomares de citros nos quais N. californicus esteja presente ou naqueles em que o predador venha a ser liberado. Esses resultados também servem para a escolha do momento mais favorável para a liberação dos ácaros predadores dessa espécie no campo, após a aplicação de agrotóxicos nos pomares. Estudos conduzidos em condições de campo ainda s

Eco-toxicological risk and impact of pesticides on important parasitoids of cabbage butterflies in cruciferous ecosystem.

Science.gov (United States)

Firake, D M; Thubru, D P; Behere, G T

2017-02-01

Eco-toxicological risk and impact of pesticides was estimated on three important parasitoids of butterflies viz., Hyposoter ebeninus, Cotesia glomerata and Pteromalus puparum. Four commonly used pesticides were evaluated using standard protocol (of IOBC/WPRS-group). In laboratory tests, the survival of the female wasps decreased significantly on fresh contact and ingestion of deltamethrin, spinosad and azadirachtin; whereas Bacillus thuringiensis var kurstaki (Btk) was found harmless pesticide. Under semi-field conditions, parasitoid mortality decreased significantly on fresh contact with the pesticides. Although, at 72 h after treatment, spinosad and deltamethrin were found harmful (Class-IV) and azadirachtin was moderately harmful (Class-III), whereas Btk was harmless (Class-I). Furthermore, 15-day-old residues of pesticides (except deltamethrin) were harmless to all parasitoid species under semi-field conditions. Notably, adult emergence and pupal duration in pesticide-treated cocoons were not significantly affected; however, their survival decreased after emergence except in Btk. The contact and oral toxicity trends of the pesticides were almost similar for three species of parasitoid females and pupae; however little variability was observed in toxicity to the host caterpillars parasitized by H. ebeninus (HCPHE) and C. glomerata (HCPCG). In semi-field tests, fresh residues of all the pesticides were harmful to HCPHE and HCPCG. However, action of Btk was slightly delayed and toxicity was rather low for HCPCG. In 15-day-old residues, deltamethrin and azadirachtin were slightly harmful to the parasitized caterpillars, whereas those of Btk and spinosad were harmless. Since, Btk appeared to be safe for parasitoids; it could be used for managing cabbage butterflies in brassicaceous crops. Copyright © 2016 Elsevier Ltd. All rights reserved.

A negative charge in transmembrane segment 1 of domain II of the cockroach sodium channel is critical for channel gating and action of pyrethroid insecticides

International Nuclear Information System (INIS)

Du Yuzhe; Song Weizhong; Groome, James R.; Nomura, Yoshiko; Luo Ningguang; Dong Ke

2010-01-01

Voltage-gated sodium channels are the primary target of pyrethroids, an important class of synthetic insecticides. Pyrethroids bind to a distinct receptor site on sodium channels and prolong the open state by inhibiting channel deactivation and inactivation. Recent studies have begun to reveal sodium channel residues important for pyrethroid binding. However, how pyrethroid binding leads to inhibition of sodium channel deactivation and inactivation remains elusive. In this study, we show that a negatively charged aspartic acid residue at position 802 (D802) located in the extracellular end of transmembrane segment 1 of domain II (IIS1) is critical for both the action of pyrethroids and the voltage dependence of channel activation. Charge-reversing or -neutralizing substitutions (K, G, or A) of D802 shifted the voltage dependence of activation in the depolarizing direction and reduced channel sensitivity to deltamethrin, a pyrethroid insecticide. The charge-reversing mutation D802K also accelerated open-state deactivation, which may have counteracted the inhibition of sodium channel deactivation by deltamethrin. In contrast, the D802G substitution slowed open-state deactivation, suggesting an additional mechanism for neutralizing the action of deltamethrin. Importantly, Schild analysis showed that D802 is not involved in pyrethroid binding. Thus, we have identified a sodium channel residue that is critical for regulating the action of pyrethroids on the sodium channel without affecting the receptor site of pyrethroids.

Hanford tank residual waste - Contaminant source terms and release models

International Nuclear Information System (INIS)

Deutsch, William J.; Cantrell, Kirk J.; Krupka, Kenneth M.; Lindberg, Michael L.; Jeffery Serne, R.

2011-01-01

Highlights: → Residual waste from five Hanford spent fuel process storage tanks was evaluated. → Gibbsite is a common mineral in tanks with high Al concentrations. → Non-crystalline U-Na-C-O-P ± H phases are common in the U-rich residual. → Iron oxides/hydroxides have been identified in all residual waste samples. → Uranium release is highly dependent on waste and leachant compositions. - Abstract: Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy's Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2-29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low ( 2 -saturated solution, or a CaCO 3 -saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO 3 -saturated solution than with the Ca(OH) 2 -saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH) 2 -saturated solution than by the CaCO 3 -saturated solution. In general, Tc is much less leachable (<10 wt.% of the

Study on recovering directly the commercial cerium oxide and total of residue rare earths from Dongpao bastnasite concentrate

International Nuclear Information System (INIS)

Nguyen Trong Hung; Nguyen Thanh Chung; Luu Xuan Dinh

2003-01-01

A technology for decomposition roasting and sequential leaching processes of Dong Pao bastnasite concentrate to recover directly commercial cerium oxide and total of residue rare earth elements from the leaching solution of the roasted product have been investigated. The bastnasite concentrate is initially roasted at temperature range of 600 - 650 degC and for time of 4 hrs in order to decompose and convert the hardly soluble carbonate forms of ore into easily soluble oxide. The roasted solid is then leached with sulfuric acid solution of 6N at 60 degC for 4 hrs to convert rare earths in oxide and fluoride form into rare earth sulfate. The recovery yield of rare earths of these stages is more than 95%. The attention has especially been paid on recovering directly the commercial cerium oxide and total of residue rare earth element from the above leaching solution. Complex ions of CeSO 4 2+ , Ce(SO 4 ) 2 , Ce(SO 4 ) 3 2- and Ce(SO 4 ) 4 4- exist in aqueous solution of cerium (IV) sulfate. Based on the property, the method of ion - sieve with DOWEX cation resin column has been applied to estimating separation of the ceric complex anions from Ln(III). The survey showed that most of the ceric complex anions are separated from total of residue rare earths. The latter which are absorbed in the cation column are recovered by elution of HCl of 4N. The recovery yield of cerium can only be reached 20% but the purity of that is very high, can be reached 99.6%. About 5 kg of CeO 2 of high grade and 5 kg of TREO of commercial specification have been produced. (author)

Multi-country assessment of residual bio-efficacy of insecticides used for indoor residual spraying in malaria control on different surface types: results from program monitoring in 17 PMI/USAID-supported IRS countries.

Science.gov (United States)

Dengela, Dereje; Seyoum, Aklilu; Lucas, Bradford; Johns, Benjamin; George, Kristen; Belemvire, Allison; Caranci, Angela; Norris, Laura C; Fornadel, Christen M

2018-01-30

Indoor residual spraying (IRS) is the application of insecticide to the interior walls of household structures that often serve as resting sites for mosquito vectors of malaria. Human exposure to malaria vectors is reduced when IRS involves proper application of pre-determined concentrations of the active ingredient specific to the insecticide formulation of choice. The impact of IRS can be affected by the dosage of insecticide, spray coverage, vector behavior, vector susceptibility to insecticides, and the residual efficacy of the insecticide applied. This report compiles data on the residual efficacy of insecticides used in IRS campaigns implemented by the United States President's Malaria Initiative (PMI)/United States Agency for International Development (USAID) in 17 African countries and compares observed length of efficacy to ranges proposed in World Health Organization (WHO) guidelines. Additionally, this study provides initial analysis on variation of mosquito mortality depending on the surface material of sprayed structures, country spray program, year of implementation, source of tested mosquitoes, and type of insecticide. Residual efficacy of the insecticides used for PMI/USAID-supported IRS campaigns was measured in Benin, Burkina Faso, Ethiopia, Ghana, Kenya, Liberia, Madagascar, Malawi, Mali, Mozambique, Nigeria, Rwanda, Senegal, Tanzania, Uganda, Zambia and Zimbabwe. The WHO cone bioassay tests were used to assess the mortality rate of mosquitoes exposed to insecticide-treated mud, wood, cement, and other commonly used housing materials. Baseline tests were performed within weeks of IRS application and follow-up tests were continued until the mortality of exposed mosquitoes dropped below 80% or the program monitoring period ended. Residual efficacy in months was then evaluated with respect to WHO guidelines that provide suggested ranges of residual efficacy for insecticide formulations recommended for use in IRS. Where the data allowed, direct

Multi-Residue studies of pesticides in fermented dried cocoa beans and selected cocoa products produced in Ghana

International Nuclear Information System (INIS)

Frimpong, S. K

2011-01-01

Cocoa is a major cash crop and contributes significantly to Ghana's economy. Majority of this contribution is as a result of foreign earnings in foreign trade partnership. Cocoa products are consumed locally aside it generating foreign income for the country. Pesticide residues above allowable limits in cocoa beans have potential detrimental effects on human health, depending on the frequency of exposure and/or the potency or toxicity of the pesticide. Pesticide residues on cocoa also attract trade sanctions from international trading partners. The approved pesticides, which are used to control pests in the growing cocoa in Ghana, are: Diazinon, Cypermethrin, Deltamethrin, Acetamiprid, Imidicloprid and Pyrethrums; nevertheless some unapproved pesticides on cocoa such as Pirimiphos-methyl, Chlorpyrifos, Endosulfan, Fenitrotion, Fenvalerate, Permethrin and others find their way for use on cocoa in Ghana. The main objective of this study was to determine the levels of pesticide residues in fermented dried cocoa beans produced and ready for export in Ghana, using gas chromatography mass spectrometry. It also seeks to provide the baseline information on contamination levels of pesticide residues in semi-finished and selected finished fermented dried cocoa beans products. Fermented dried cocoa beans were sampled at random in the two main COCOBOD warehouses located in Tema and Takoradi. Semi-finished and finished cocoa products were obtained from processing industries in Tema. Two extraction methods were used. The second extraction method was as by the QuEChERS method for vegetable oils which was used for the cocoa butter samples only, after being liquefied in water bath at 40 degrees celsius. The investigated pesticides consisted of fifteen organochlorine pesticides, thirteen organophosphorous pesticides and nine synthetic pyrethroids pesticides. Percentage recoveries ranged from 70-110 percent, with instrumental detection limits of 0.3ug/kg, 0.15ug/g and 0.15ug/g for

Erythrocyte osmotic fragility and lipid peroxidation following chronic co-exposure of rats to chlorpyrifos and deltamethrin, and the beneficial effect of alpha-lipoic acid

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Chidiebere Uchendu

2014-01-01

Full Text Available The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF and deltamethrin (DLT on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil and II (ALA were given soya oil (2 ml/kg and ALA (60 mg/kg, respectively. Rats in group III (DLT and IV (CPF were exposed to DLT (6.25 mg/kg and CPF (4.75 mg/kg (1/20th of the previously determined LD50 of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h. Rats in group V (CPF + DLT were co-exposed to CPF (4.75 mg/kg and DLT (6.25 mg/kg, while those in group VI (ALA + CPF + DLT were pretreated with ALA (60 mg/kg and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

Forensic analysis of high explosives residues in post-blast water samples employing solid phase extraction for analyte pro-concentration

International Nuclear Information System (INIS)

Umi Kalsom Ahmad; Rajendran, Sumathy; Ling, Lee Woan

2008-01-01

Nitro aromatic, nitramine and nitrate ester compounds are a major group of high order explosive or better known as military explosives. Octahydro-1,3,5,7-tetrazocine (HMX), 1,3,5-hexahydro-1,3,5-trinitro triazine (RDX), 2,4,6-trinitro-toluene (TNT), pentaerythritol tetranitrate (PETN) and 2,4-dinitrotoluene (2,4-DNT) are secondary high explosives classified as most commonly used explosives components. There is an increasing demand for pre-concentration of these compounds in water samples as the sensitivity achieved by instrumental analytical methods for these high explosives residues are the main drawback in the application at trace levels for forensic analysis. Hence, a simple cartridge solid phase extraction (SPE) procedure was optimized as the off-line extraction and pre-concentration method to enhance the detection limit of high explosive residues using micellar electrokinetic chromatography (MEKC) and gas chromatography with electron-capture detection (GC-ECD) methods. The SPE cartridges utilized LiChrolut EN as the SPE adsorbent. By emplying pre-concentration using SPE, the detection limits of the target analytes in water sample were lowered by more than 1000 times with good percentage recovery (>87%) for MEKC method and lowered by 120 times with more than 2 % percentage recovery for GC-ECD methods. In order to test the feasibility of the developed method to real cases, post-blast water samples were analyzed. The post-blast water samples which were collected from Baling Bom training range, Ulu Kinta, Perak contained RDX and PETN in the range of 0.05 - 0.17 ppm and 0.0124 - 0.0390 ppm respectively. (author)

Multiclass pesticide determination in olives and their processing factors in olive oil: comparison of different olive oil extraction systems.

Science.gov (United States)

Amvrazi, Elpiniki G; Albanis, Triantafyllos A

2008-07-23

The processing factors (pesticide concentration found in olive oil/pesticide concentration found in olives) of azinphos methyl, chlorpyrifos, lambda-cyhalothrin, deltamethrin, diazinon, dimethoate, endosulfan, and fenthion were determined in olive oil production process in various laboratory-scale olive oil extractions based on three- or two-phase centrifugation systems in comparison with samples collected during olive oil extractions in conventional olive mills located at different olive oil production areas in Greece. Pesticide analyses were performed using a multiresidue method developed in our laboratory for the determination of different insecticides and herbicides in olive oil by solid-phase extraction techniques coupled to gas chromatography detection (electron capture detection and nitrogen phosphorus detection), optimized, and validated for olive fruits sample preparation. Processing factors were found to vary among the different pesticides studied. Water addition in the oil extraction procedure (as in a three-phase centrifugation system) was found to decrease the processing factors of dimethoate, alpha-endosulfan, diazinon, and chlorpyrifos, whereas those of fenthion, azinphos methyl, beta-endosulfan, lambda-cyhalothrin, and deltamethrin residues were not affected. The water content of olives processed was found to proportionally affect pesticide processing factors. Fenthion sulfoxide and endosulfan sulfate were the major metabolites of fenthion and endosulfan, respectively, that were detected in laboratory-produced olive oils, but only the concentration of fenthion sulfoxide was found to increase with the increase of water addition in the olive oil extraction process.

Pyrethroid toxicity in silver catfish, Rhamdia quelen

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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

Deltamethrin Binding to Triatoma infestans (Hemiptera: Reduviidae) Lipoproteins. Analysis by Solvent Bar Microextraction Coupled to Gas Chromatography.

Science.gov (United States)

Dulbecco, A B; Mijailovsky, S J; Girotti, J R; Juárez, M P

2015-11-01

The binding of deltamethrin (DLM) to the hemipteran Triatoma infestans (Klug) hemolymph lipoproteins was evaluated in vitro. After DLM incubation with the insect hemolymph, lipoproteins were fractioned by ultracentrifugation. DLM binding was analyzed by a microextractive technique-solvent bar microextraction-a solventless methodology to extract DLM from each lipoprotein fraction. This is a novel use of the technique applied to extract an insecticide from an insect fluid. Capillary gas chromatography with microelectron capture detection was used to detect DLM bound by the T. infestans hemolymph lipoproteins and to identify the preferred DLM carrier. We show that Lp and VHDLp I lipoproteins are mainly responsible for DLM transport in T. infestans, both in DLM-resistant and DLM-susceptible bugs. Our results also indicate that DLM amounts transported are not related to DLM susceptibility. © 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.

Arsenic Species in Chicken Breast: Temporal Variations of Metabolites, Elimination Kinetics, and Residual Concentrations.

Science.gov (United States)

Liu, Qingqing; Peng, Hanyong; Lu, Xiufen; Zuidhof, Martin J; Li, Xing-Fang; Le, X Chris

2016-08-01

Chicken meat has the highest per capita consumption among all meat types in North America. The practice of feeding 3-nitro-4-hydroxyphenylarsonic acid (Roxarsone, Rox) to chickens lasted for more than 60 years. However, the fate of Rox and arsenic metabolites remaining in chicken are poorly understood. We aimed to determine the elimination of Rox and metabolites from chickens and quantify the remaining arsenic species in chicken meat, providing necessary information for meaningful exposure assessment. We have conducted a 35-day feeding experiment involving 1,600 chickens, of which half were control and the other half were fed a Rox-supplemented diet for the first 28 days and then a Rox-free diet for the final 7 days. We quantified the concentrations of individual arsenic species in the breast meat of 229 chickens. Rox, arsenobetaine, arsenite, monomethylarsonic acid, dimethylarsinic acid, and a new arsenic metabolite, were detected in breast meat from chickens fed Rox. The concentrations of arsenic species, except arsenobetaine, were significantly higher in the Rox-fed than in the control chickens. The half-lives of elimination of these arsenic species were 0.4-1 day. Seven days after termination of Rox feeding, the concentrations of arsenite (3.1 μg/kg), Rox (0.4 μg/kg), and a new arsenic metabolite (0.8 μg/kg) were significantly higher in the Rox-fed chickens than in the control. Feeding of Rox to chickens increased the concentrations of five arsenic species in breast meat. Although most arsenic species were excreted rapidly when the feeding of Rox stopped, arsenic species remaining in the Rox-fed chickens were higher than the background levels. Liu Q, Peng H, Lu X, Zuidhof MJ, Li XF, Le XC. 2016. Arsenic species in chicken breast: temporal variations of metabolites, elimination kinetics, and residual concentrations. Environ Health Perspect 124:1174-1181; http://dx.doi.org/10.1289/ehp.1510530.

Decomposition of dilute residual active chlorine in sea-water

International Nuclear Information System (INIS)

Yoshinaga, Tetsutaro; Kawano, Kentaro; Yanagase, Kenjiro; Shiga, Akira

1985-01-01

Coastal industries such as power stations require enormous quantities of sea-water for cooling, but the marine organisms in it often result in fouling and/or blockade of the circulating water condenser and pipeworks. To prevent this, chlorine, or hypochlorite by the direct electrolysis of sea-water have been added. Environmental concerns, however, dictate that the residual chlorine concentration at the outlet should be less than the regulated value (0.02 ppm). Methods for decomposing dilute residual chlorine solutions were therefore studied. It was found that: 1) The addition of (raw) sea-water to the sea-water which passed through the condenser lowered the residual chlorine concentration to an greater extent than could be expected by dilution only. 2) Ozonation of the residual chlorine solution led to degradation of OCl - , but in solutions with a residual chlorine concentrations of less than 3 -- 4 ppm, ozonation had no effect. 3) Irradiation with ultra violet light (254 nm) decomposed the residual chlorine. Under the present work conditions (25 0 C: pH 8; depth 10 mm), nearly first order kinetics were to hold [da/dt = ksub((1)) (1-a)sup(n)]. There is a proportional relationship between the kinetic constant (k) and illuminous intensity (L), i.e., ksub((1))[C 0 sup(Cl 2 ): 10 ppm] = 6.56 x 10 -5 L (L = 0 -- 1000 lx). Thus, the use of both sea-water addition and UV irradiation provides a probable method for decomposing a residual chlorine to the expected concentration. (author)

The acaricidal efficacy of peracetic acid and deltamethrin against the fowl tick, Argas persicus, infesting laying hens.

Science.gov (United States)

Khater, Hanem F; Seddiek, Shaker A; El-Shorbagy, Mohamed M; Ali, Ali M

2013-01-01

The fowl tick, Argas persicus (Oken), is of veterinary importance as a parasite of poultry and wild birds. The antitick efficacy, in vitro and in vivo, of peracetic acid (PAA) and deltamethrin (DMT) was tested separately against A. persicus through the dipping technique. PAA (0.5 %) was highly efficient against soft tick larvae (A. persicus), resulting in 100 % mortality after 2 min. The lethal concentrations LC(50) and LC(95) were 0.310 and 0.503 %, respectively. The lethal time values LT(50) and LT(95) were 5.34 and 40.00 min, respectively, after treatment with PAA (0.25 %). Two minutes after exposure to DMT, LC(50) and LC(95) values were 0.033 and 0.052 % (33.204 and 51.527 mg/L), respectively. The LT(50) and LT(95) values were 27.03 and 305.46 min, respectively, after treatment with 0.025 % DMT (25 mg/L). After dipping in PAA (0.5 %), the chickens did not show respiratory signs or inflammation on the eyes and/or skin. By contrast, temporary coughing, sneezing, and ocular inflammations without dermatitis were observed in chickens dipped in DMT (0.05 % or 50 mg /L). Seven days posttreatment (PT), the reduction in the percentages of A. persicus infesting laying hens were 99.15 and 63.42 % after dipping in PAA and DMT, respectively. However, complete elimination of the number of ticks occurred after 28 days PT with DMT. PAA inhibits molting effectively (28 %) when compared with that of DMT (52 %). Results indicated that PAA is a more potent and promising acaricide against A. persicus (in vitro and in vivo) than DMT.

Americium recovery from reduction residues

Science.gov (United States)

Conner, W.V.; Proctor, S.G.

1973-12-25

A process for separation and recovery of americium values from container or bomb'' reduction residues comprising dissolving the residues in a suitable acid, adjusting the hydrogen ion concentration to a desired level by adding a base, precipitating the americium as americium oxalate by adding oxalic acid, digesting the solution, separating the precipitate, and thereafter calcining the americium oxalate precipitate to form americium oxide. (Official Gazette)

Alkali solution extraction of rice residue protein isolates: Influence of alkali concentration on protein functional, structural properties and lysinoalanine formation.

Science.gov (United States)

Hou, Furong; Ding, Wenhui; Qu, Wenjuan; Oladejo, Ayobami Olayemi; Xiong, Feng; Zhang, Weiwei; He, Ronghai; Ma, Haile

2017-03-01

This study evaluated the nutrient property and safety of the rice residue protein isolates (RRPI) product (extracted by different alkali concentrations) by exploring the protein functional, structural properties and lysinoalanine (LAL) formation. The results showed that with the rising of alkali concentration from 0.03M to 0.15M, the solubility, emulsifying and foaming properties of RRPI increased at first and then descended. When the alkali concentration was greater than 0.03M, the RRPI surface hydrophobicity decreased and the content of thiol and disulfide bond, Lys and Cys significantly reduced. By the analysis of HPLC, the content of LAL rose up from 276.08 to 15,198.07mg/kg and decreased to 1340.98mg/kg crude protein when the alkali concentration increased from 0.03 to 0.09M and until to 0.15M. These results indicated that RRPI alkaline extraction concentration above 0.03M may cause severe nutrient or safety problems of protein. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antibiotic Residues - A Global Health Hazard

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Nisha A.R.

Full Text Available Use of Antibiotic that might result in deposition of residues in meat, milk and eggs must not be permitted in food intended for human consumption. If use of antibiotics is necessary as in prevention and treatment of animal diseases, a withholding period must be observed until the residues are negligible or no longer detected. The use of antibiotics to bring about improved performance in growth and feed efficiency, to synchronize or control of reproductive cycle and breeding performance also often lead to harmful residual effects. Concern over antibiotic residues in food of animal origin occurs in two times; one which produces potential threat to direct toxicity in human, second is whether the low levels of antibiotic exposure would result in alteration of microflora, cause disease and the possible development of resistant strains which cause failure of antibiotic therapy in clinical situations. A withdrawal period is established to safeguard human from exposure of antibiotic added food. The withdrawal time is the time required for the residue of toxicological concern to reach safe concentration as defined by tolerance. It is the interval from the time an animal is removed from medication until permitted time of slaughter. Heavy responsibility is placed on the veterinarian and livestock producer to observe the period for a withdrawal of a drug prior to slaughter to assure that illegal concentration of drug residue in meat, milk and egg do not occur. Use of food additives may improve feed efficiency 17% in beef cattle, 10% in lambs, 15% in poultry and 15% in swine. But their indiscriminate use will produce toxicity in consumers. WHO and FAO establish tolerances for a drug, pesticide or other chemical in the relevant tissues of food producing animals. The tolerance is the tissue concentration below, which a marker residue for the drug or chemical must fall in the target tissue before that animal edible tissues are considered safe for human

Estimation of human body concentrations of DDT from indoor residual spraying for malaria control

International Nuclear Information System (INIS)

Gyalpo, Tenzing; Fritsche, Lukas; Bouwman, Henk; Bornman, Riana; Scheringer, Martin; Hungerbühler, Konrad

2012-01-01

Inhabitants of dwellings treated with DDT for indoor residual spraying show high DDT levels in blood and breast milk. This is of concern since mothers transfer lipid-soluble contaminants such as DDT via breastfeeding to their children. Focusing on DDT use in South Africa, we employ a pharmacokinetic model to estimate DDT levels in human lipid tissue over the lifetime of an individual to determine the amount of DDT transferred to children during breastfeeding, and to identify the dominant DDT uptake routes. In particular, the effects of breastfeeding duration, parity, and mother's age on DDT concentrations of mother and infant are investigated. Model results show that primiparous mothers have greater DDT concentrations than multiparous mothers, which causes higher DDT exposure of first-born children. DDT in the body mainly originates from diet. Generally, our modeled DDT levels reproduce levels found in South African biomonitoring data within a factor of 3. - Highlights: ► Comparison of one-compartment pharmacokinetic model with biomonitoring data. ► Pre- and postnatal exposure of infants depends on breastfeeding duration and parity. ► Dietary exposure of DDT is the dominant uptake route in South Africa. ► Elimination half-lives of DDT and DDE are shorter in children than in adults. - Model predictions of a one-compartment pharmacokinetic model confirm the trends of DDT found in human samples of inhabitants living in DDT-treated dwellings.

Deltamethrin-Induced Hepatotoxicity and Virgin Olive Oil Consumption: An Experimental Study.

Science.gov (United States)

Khalatbary, Ali Reza; Ghabaee, Davood Nasiry Zarrin; Ahmadvand, Hassan; Amiri, Fereshteh Talebpour; Lehi, Somaieh Tadayoni

2017-11-01

Deltamethrin (DM) is a synthetic pyrethroid insecticide which can lead to pathological effects in mammals through oxidative stress. On the other hand, virgin olive oil (VOO) is a rich source of phenolic compounds with antioxidants. The aim of the present study was to determine the protective effects of VOO against DM-induced hepatotoxicity. Thirty-six mice were randomly separated into 4 groups: vehicle group, VOO group, DM group, and DM plus VOO group. Immunohistochemistry of PARP, COX-2, and caspase-3 with the biochemical analysis of malondialdehyde and total antioxidant capacity levels were performed in the liver samples 5 weeks after gavaging. Statistical analysis was performed using SPSS, version 15. The data were compared between the groups using the Tukey multiple comparison tests and the analysis of the variance. A P value group (71.18±0.01), whereas it was significantly (P=0.001) decreased after VOO administration in the DM plus VOO group (39.59±2.43). While the total antioxidant capacity level in the liver was decreased in the DM group (3.05±0.05), it was significantly increased (P=0.03) after VOO administration in the DM plus VOO group (3.95±0.04). A greater expression of caspase-3 (P=0.008), COX-2 (P =0.004), and PARP (P 0.006) could be detected in the DM group, while it was significantly (P=0.009) attenuated in the DM plus VOO group. Also, the degeneration of hepatocytes, which was detected in the DM group, was attenuated after VOO consumption. VOO exerted protective effects against DM-induced hepatotoxicity, which might be associated with its anti-apoptotic, anti-inflammatory, and antioxidative properties.

Erratum to: the acaricidal efficacy of peracetic acid and deltamethrin against the fowl tick, Argas persicus, infesting laying hens.

Science.gov (United States)

Khater, Hanem F; Seddiek, Shaker A; El-Shorbagy, Mohamed M; Ali, Ali M

2013-10-01

The fowl tick, Argas persicus (Oken), is of veterinary importance as a parasite of poultry and wild birds. The antitick efficacy, in vitro and in vivo, of peracetic acid (PAA) and deltamethrin (DMT) was tested separately against A. persicus through the dipping technique. PAA (0.5%) was highly efficient against soft tick larvae (A. persicus), resulting in 100 % mortality after 2 min. The lethal concentrations LC₅₀ and LC₉₅ were 0.310 and 0.503 %, respectively. The lethal time values LT₅₀ and LT₉₅ were 5.34 and 40.00 min, respectively, after treatment with PAA (0.25%). Two minutes after exposure to DMT, LC₅₀ and LC₉₅ values were 0.0033 and 0.0052% (33.204 and 51.527 mg/L), respectively. The LT₅₀ and LT₉₅ values were 27.03 and 305.46 min, respectively, after treatment with 0.0025% DMT (25 mg/L). After dipping in PAA (0.5%), the chickens did not show respiratory signs or inflammation on the eyes and/or skin. By contrast, temporary coughing, sneezing, and ocular inflammations without dermatitis were observed in chickens dipped in DMT (0.005 % or 50 mg /L). Seven days posttreatment (PT), the reduction in the percentages of A. persicus infesting laying hens were 99.15 and 63.42% after dipping in PAA and DMT, respectively. However, complete elimination of the number of ticks occurred after 28 days PT with DMT. PAA inhibits molting effectively (28%) when compared with that of DMT (52%). Results indicated that PAA is a more potent and promising acaricide against A. persicus (in vitro and in vivo) than DMT.

Radionuclides in Bayer process residues: previous analysis for radiological protection

International Nuclear Information System (INIS)

Cuccia, Valeria; Rocha, Zildete; Oliveira, Arno H. de

2011-01-01

Natural occurring radionuclides are present in many natural resources. Human activities may enhance concentrations of radionuclides and/or enhance potential of exposure to naturally occurring radioactive material (NORM). The industrial residues containing radionuclides have been receiving a considerable global attention, because of the large amounts of NORM containing wastes and the potential long term risks of long-lived radionuclides. Included in this global concern, this work focuses on the characterization of radioactivity in the main residues of Bayer process for alumina production: red mud and sand samples. Usually, the residues of Bayer process are named red mud, in their totality. However, in the industry where the samples were collected, there is an additional residues separation: sand and red mud. The analytical techniques used were gamma spectrometry (HPGe detector) and neutron activation analysis. The concentrations of radionuclides are higher in the red mud than in the sand. These solid residues present activities concentrations enhanced, when compared to bauxite. Further uses for the residues as building material must be more evaluated from the radiological point of view, due to its potential of radiological exposure enhancement, specially caused by radon emission. (author)

Studies on influence of environmental factors on concentration on concentration of radionuclides

International Nuclear Information System (INIS)

Anon.

1974-01-01

Environmental factors which seemed to influence the concentration of radionuclides to marine organisms including illumination, water temperature, coexisting stable elements, salt concentration, suspended matters in sea water and residue were studied. The influence of illumination was examined by algae using 137 Cs, 60 Co, 85 Sr, and 106 Ru as tracers, within 24 hours of illumination. The concentration of 137 Cs and 60 Co revealed remarkable increase of uptake in accordance with increasing illumination intensity, and 24 hours illumination showed 2 times concentration of that by 4 hours'. 85 Sr and 106 Ru showed no effect of illumination, and suggested their concentration was depending on adsorption to the surface. As for water temperature, the concentration factor of 65 Zn, 137 Cs obtained from fishes and shells by 22 0 C breeding was 2 times of that by 12 0 C breeding. Concerning the influence of coexisting stable elements, fishes and shells were examined by 54 Mn, 60 Co, and 65 Zn as tracers. When the stable elements concentration in sea water became 10 times the normal, concentration factor depending on adsorption and metabolism became respective one tenth and one second of the normal value. The influence of salt concentration was examined using 85 Sr, 65 Zn, and 137 Cs, and revealed that 28 to 40 per cent changes of salt level gave slight influence on concentration factor. In order to study the influence of suspended matters and quality of residue, 3 kinds of 106 Ru complex species were added. Concentration factor of Hijiki (Hijikia fusiforme) showed no remarkable difference between breeding in filtrated and non-filtrated sea water. However, clams living in the sand should be taken care of the concentration by the residue in the sea bottom. (Kanao, N.)

Daily Intake of Protein from Cod Residual Material Lowers Serum Concentrations of Nonesterified Fatty Acids in Overweight Healthy Adults: A Randomized Double-Blind Pilot Study

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Iselin Vildmyren

2018-06-01

Full Text Available Improved process technologies have allowed fishing vessels to utilize residuals from cod fillet production (head, backbone, skin, cuttings, and entrails and convert this to high-quality protein powders for human consumption. In this double-blind pilot study, 42 healthy overweight or obese adults were randomized to three experimental groups consuming tablets corresponding to 6 g/day of proteins from cod residuals as presscake meal (Cod-PC, presscake and stickwater meal (Cod-PCW, or placebo tablets (control for eight weeks. The primary outcome of this study was changes in metabolites related to glucose regulation in overweight or obese healthy adults after intake of proteins from cod residuals. Cod-PC supplementation decreased postprandial serum nonesterified fatty acids (NEFA concentration and increased gene expressions of diglyceride acyltransferase 1 and 2 in subcutaneous adipose tissue compared with controls. Fasting insulin increased while fasting NEFA and 120-min postprandial glucose decreased within the Cod-PC group, but these changes did not differ from the other groups. In conclusion, supplementation with Cod-PC beneficially affected postprandial serum NEFA concentration compared with the other groups in overweight or obese adults. Supplementation with Cod-PCW, which contains a higher fraction of water-soluble protein compared to Cod-PC, did not affect serum markers of glucose regulation.

Characterisation and management of concrete grinding residuals.

Science.gov (United States)

Kluge, Matt; Gupta, Nautasha; Watts, Ben; Chadik, Paul A; Ferraro, Christopher; Townsend, Timothy G

2018-02-01

Concrete grinding residue is the waste product resulting from the grinding, cutting, and resurfacing of concrete pavement. Potential beneficial applications for concrete grinding residue include use as a soil amendment and as a construction material, including as an additive to Portland cement concrete. Concrete grinding residue exhibits a high pH, and though not hazardous, it is sufficiently elevated that precautions need to be taken around aquatic ecosystems. Best management practices and state regulations focus on reducing the impact on such aquatic environment. Heavy metals are present in concrete grinding residue, but concentrations are of the same magnitude as typically recycled concrete residuals. The chemical composition of concrete grinding residue makes it a useful product for some soil amendment purposes at appropriate land application rates. The presence of unreacted concrete in concrete grinding residue was examined for potential use as partial replacement of cement in new concrete. Testing of Florida concrete grinding residue revealed no dramatic reactivity or improvement in mortar strength.

Wet high-intensity magnetic separation for the concentration of Witwatersrand gold-uranium ores and residues

International Nuclear Information System (INIS)

Corrans, I.J.; Levin, J.

1979-01-01

Wet high-intensity magnetic separation (WHIMS) for the concentration of gold and uranium was tested on many Witwatersrand cyanidation residues, and on some ores and flotation tailings. The results varied, but many indicated recoveries of over 60 per cent of the gold and uranium. The main source of loss is the inefficiency of WHIMS for material of smaller particle size than 20μm. The recoveries in the continuous tests were lower than those in the batch tests. The continuous tests indicated an operational difficulty that could be experienced in practice, namely the tendency for wood chips and ferromagnetic particles to block the matrix of the separator. It was decided that a solution to the problem lies in the modification of the separator to allow continuous removal of the matrix for cleaning. A system has been developed for this purpose and is being demonstrated on a pilot-plant scale. Promising results were obtained in tests on a process that combines a coarse grind, gravity concentration, and WHIMS. In the gravity-concentration step, considerable recoveries, generally over 50 per cent, of high-grade pyrite were obtained, together with high recoveries of gold and moderate, but possibly important, recoveries of uranium. A simple model describing the operation of the WHIMS machine in terms of the operating parameters is described. This should reduce the amount of empirical testwork required for the optimization of operating conditions and should provide a basis for scale-up calculations. The economics of the WHIMS process is discussed [af

Evidence of carbamate resistance in urban populations of Anopheles gambiae s.s. mosquitoes resistant to DDT and deltamethrin insecticides in Lagos, South-Western Nigeria

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Oduola Adedayo O

2012-06-01

Full Text Available Abstract Background Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of Anopheles gambiae to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin. Methods Two – three day old adult female Anopheles mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the Anopheles gambiae population to bendiocarb insecticide. Members of the A. gambiae complex, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO synergist assays. The presence of kdr-w/e and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR. Results Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05 but was significantly higher (P A. gambiae s.s (M form. The kdr -w point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. Ace-1R point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted. Conclusion Evidence of carbamate resistance in A. gambiae populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of

Deltamethrin-Induced Hepatotoxicity and Virgin Olive Oil Consumption: An Experimental Study

Directory of Open Access Journals (Sweden)

Ali Reza Khalatbary

2017-11-01

Full Text Available Background: Deltamethrin (DM is a synthetic pyrethroid insecticide which can lead to pathological effects in mammals through oxidative stress. On the other hand, virgin olive oil (VOO is a rich source of phenolic compounds with antioxidants. The aim of the present study was to determine the protective effects of VOO against DM-induced hepatotoxicity. Methods: Thirty-six mice were randomly separated into 4 groups: vehicle group, VOO group, DM group, and DM plus VOO group. Immunohistochemistry of PARP, COX-2, and caspase-3 with the biochemical analysis of malondialdehyde and total antioxidant capacity levels were performed in the liver samples 5 weeks after gavaging. Statistical analysis was performed using SPSS, version 15. The data were compared between the groups using the Tukey multiple comparison tests and the analysis of the variance. A P value <0.05 was considered significant. Results: The malondialdehyde level in the liver was increased in the DM group (71.18±0.01, whereas it was significantly (P=0.001 decreased after VOO administration in the DM plus VOO group (39.59±2.43. While the total antioxidant capacity level in the liver was decreased in the DM group (3.05±0.05, it was significantly increased (P=0.03 after VOO administration in the DM plus VOO group (3.95±0.04. A greater expression of caspase-3 (P=0.008, COX-2 (P =0.004, and PARP (P 0.006 could be detected in the DM group, while it was significantly (P=0.009 attenuated in the DM plus VOO group. Also, the degeneration of hepatocytes, which was detected in the DM group, was attenuated after VOO consumption. Conclusions: VOO exerted protective effects against DM-induced hepatotoxicity, which might be associated with its anti-apoptotic, anti-inflammatory, and antioxidative properties.

Associação de deltametrina com Acarophenax lacunatus e seu impacto sobre o desenvolvimento de Rhyzopertha dominica Association of deltamethrin with Acarophenax lacunatus on development of Rhyzopertha dominica

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José Roberto Gonçalves

2006-08-01

Full Text Available O objetivo deste trabalho foi avaliar a associação do inseticida deltametrina, aplicado em grãos de trigo, com o ácaro parasita Acarophenax lacunatus e seu impacto sobre o desenvolvimento de Rhyzopertha dominica. Grãos de trigo (13% de teor de água foram tratados com diferentes doses de deltametrina (0,00, 0,125, 0,25, 0,375, 0,50, 0,625, 0,75, 0,875 e 1,00 mg i.a. kg-1. As unidades experimentais consistiram de placas de Petri contendo 30 g de grãos tratados, ou não, com o inseticida, infestados com 30 adultos de R. dominica. Cinco dias depois da infestação, foram inoculados cinco ácaros parasitas por unidade experimental, em sete repetições. As unidades experimentais foram armazenadas por 60 dias depois da infestação em câmara climatizada ajustada a 30±1°C, 60±5% UR e escotofase de 24 horas. A taxa instantânea de crescimento de R. dominica apresentou índices negativos para as doses de deltametrina maiores que 0,25 mg i.a. kg-1. A. lacunatus associado a doses de deltametrina menores que 0,5 mg i.a. kg-1 reduz as fases imaturas de R. dominica.The objective of this work was to evaluate the development of Rhyzopertha dominica on wheat grain treated with the insecticide deltamethrin and infested with the mite Acarophenax lacunatus. The experimental units were Petri dishes containing 30 g of wheat grain (13% moisture content sprayed with different doses of deltamethrin (0.00, 0.125, 0.25, 0.375, 0.50, 0.625, 0.75, 0.875 and 1.00 mg a.i. kg-1 infested with 30 adults of R. dominica. Five days after the infestation, five mites were inoculated on each experimental unit, in seven replicates. All treatments were maintained under controlled conditions (30±1°C, 60±5% r.h. and 24 hours scotophase for 60 days after the infestation. The instantaneous rate of increase of R. dominica was negative under doses higher than 0.25 mg a.i. kg-1. The lowest number of immature R. dominica was observed with the interaction between deltamethrin doses

Hazardous properties of paint residues from the furniture industry.

Science.gov (United States)

Vaajasaari, Kati; Kulovaara, Maaret; Joutti, Anneli; Schultz, Eija; Soljamo, Kari

2004-01-30

The objective of this study was to screen nine excess paint residues for environmental hazard and to evaluate their disposability in a non-hazardous or hazardous-waste landfill. These residues were produced in the process of spray-painting furniture. Residues were classified according to their leaching and ecotoxicological properties. Leaching properties were determined with the European standard SFS-EN 12457-2 leaching-test. The toxicity of the leaching-test eluates was measured with plant-, bacteria- and enzyme-inhibition bioassays. Total organic carbon, formaldehyde and solvent concentrations in the solid wastes and in the leaching-test eluates were analysed. It seemed likely that leached formaldehyde caused very high acute toxicity in leaching-test eluates of the dry-booth residues. This hypothesis was based on the fact that the formaldehyde concentrations in the leaching-test eluates of the dry-booth residues were 62-75 times higher than the EC50 value reported in the literature for formaldehyde. The results of the water-curtain booth residues showed that the samples with the highest TOC and aromatic solvent concentrations were also the most toxic. The studied excess paint residues were complex organic mixtures and contained large amounts of compounds not identifiable from chemical data. Therefore, the evaluation of the hazard based solely on available chemical data is unlikely to be sufficient, as evidenced by our study. Our results show that harmful compounds remain in the solid waste and the toxicity results of their leaching-test eluates show that toxicity may leach from residues in contact with water at landfill sites. They also confirm the benefit of combining chemical and ecotoxicological assays in assessing the potential environmental hazard of complex organic mixtures found in wastes. Copyright 2003 Elsevier B.V.

Determination of Residual Chlorine and Turbidity in Drinking Water. Instructor's Manual.

Science.gov (United States)

Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

This instructor's guide presents analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. This publication is intended…

Determination of Residual Chlorine and Turbidity in Drinking Water. Student Manual.

Science.gov (United States)

Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

This student's manual covers analytical methods for residual chlorine and turbidity. Topics include sample handling, permissable concentration levels, substitution of residual chlorine for bacteriological work, public notification, and the required analytical techniques to determine residual chlorine and turbidity. The publication is intended for…

Evaluation of droplet digital PCR for quantification of residual leucocytes in red blood cell concentrates.

Science.gov (United States)

Doescher, A; Loges, U; Petershofen, E K; Müller, T H

2017-11-01

Enumeration of residual white blood cells in leucoreduced blood components is essential part of quality control. Digital PCR has substantially facilitated quantitative PCR and was thus evaluated for measurements of leucocytes. Target for quantification of leucocytes by digital droplet PCR was the blood group gene RHCE. The SPEF1 gene was added as internal control for the entire assay starting with automated DNA extraction. The sensitivity of the method was determined by serial dilutions of standard samples. Quality control samples were analysed within 24 h, 7 days and 6 months after collection. Routine samples from leucodepleted red blood cell concentrates (n = 150) were evaluated in parallel by flow-cytometry (LeucoCount) and by digital PCR. Digital PCR reliably detected at least 0·4 leucocytes per assay. The mean difference between PCR and flow-cytometric results from 150 units was -0·01 (±1·0). DNA samples were stable for up to at least six months. PCR measurement of leucocytes in samples from plasma and platelet concentrates also provided valid results in a pilot study. Droplet digital PCR to enumerate leucocytes offers an alternative for quality control of leucoreduced blood products. Sensitivity, specificity and reproducibility are comparable to flow-cytometry. The option to collect samples over an extended period of time and the automatization introduce attractive features for routine quality control. © 2017 International Society of Blood Transfusion.

Assessing risks of pesticides targeting lepidopteran pests in cruciferous ecosystems to eggs parasitoid, Trichogramma brassicae (Bezdenko

Directory of Open Access Journals (Sweden)

D.P. Thubru

2018-05-01

Full Text Available Lethal and sub lethal effects of fresh and old residues of azadirachtin, spinosad, Bacillus thuringiensis var. kurstaki (Bt var. k, and deltamethrin, were evaluated at their recommended field doses against adult and immature stages of Trichogramma brassicae under in vitro conditions. The experiments were carried out at the Entomology section of Division of Crop Protection, ICAR Research Complex for NEH region, Umiam, Meghalaya, in 2012–2013. The effects of different pesticides were determined by bioassays using the residual film method, the diet contamination method, the pupal dip method and the topical application technique. The four pesticides were found harmful to adult T. brassicae after ingestion, however surface contact bioassays revealed that Bt var. k was the least toxic pesticide. Except Bt var. k, other three pesticides were found harmful also to the immature stages of T. brassicae and significantly affected parasitism potential, adult emergence, longevity of adults, and sex ratio of the progeny. Deltamethrin and azadirachtin were the most harmful, even after 15 days of application. Spinosad was found to be relatively safe to T. brassicae after 15 days of application. As Bt appeared to be the least toxic pesticide for T. brassicae, it could be used for the management of severe infestations of lepidopteran pests in cruciferous ecosystems.If essential, spinosad may be used 15 days after parasitoid release, thus minimizing the chances of parasitoid exposure. Keywords: Azadirachtin, Bacillus thuringiensis, Deltamethrin, Spinosad

Pesticide residue quantification analysis by hyperspectral imaging sensors

Science.gov (United States)

Liao, Yuan-Hsun; Lo, Wei-Sheng; Guo, Horng-Yuh; Kao, Ching-Hua; Chou, Tau-Meu; Chen, Junne-Jih; Wen, Chia-Hsien; Lin, Chinsu; Chen, Hsian-Min; Ouyang, Yen-Chieh; Wu, Chao-Cheng; Chen, Shih-Yu; Chang, Chein-I.

2015-05-01

Pesticide residue detection in agriculture crops is a challenging issue and is even more difficult to quantify pesticide residue resident in agriculture produces and fruits. This paper conducts a series of base-line experiments which are particularly designed for three specific pesticides commonly used in Taiwan. The materials used for experiments are single leaves of vegetable produces which are being contaminated by various amount of concentration of pesticides. Two sensors are used to collected data. One is Fourier Transform Infrared (FTIR) spectroscopy. The other is a hyperspectral sensor, called Geophysical and Environmental Research (GER) 2600 spectroradiometer which is a batteryoperated field portable spectroradiometer with full real-time data acquisition from 350 nm to 2500 nm. In order to quantify data with different levels of pesticide residue concentration, several measures for spectral discrimination are developed. Mores specifically, new measures for calculating relative power between two sensors are particularly designed to be able to evaluate effectiveness of each of sensors in quantifying the used pesticide residues. The experimental results show that the GER is a better sensor than FTIR in the sense of pesticide residue quantification.

Fermentative utilization of glycerol residue for the production of acetic acid

Science.gov (United States)

Irvan; Trisakti, B.; Hasibuan, R.; Joli, M.

2018-02-01

Glycerol residue, frequently known as pitch, is a waste produced from the downstream product of crude glycerine distillation. With the increasing need of pure glycerine in the world, the glycerol residue produced is also increasing. Glycerol residue is a solid waste at room temperature, highly alkaline (pH > 13), corrosive, and categorized as hazardous and poisonous waste. In this research, acetic acid was produced from glycerol residue through the anaerobic fermentation process by using purple non-sulphur photosynthetic bacteria. The purpose of this study was to find out the influence of concentration change of glycerol residue on time and to find out the possibility of glycerol residue to be utilized as acetic acid. In this research, at first 400 g of glycerol residue was diluted with 200 ml of distilled water to change the glycerine phase, from solid to liquid at room temperature, acidified by using hydrochloric acid until pH 2. The top layer formed was fatty acid and triglycerides that should be removed. Meanwhile, the bottom layer was diluted glycerol residue which was then neutralized with caustic soda. To produce acetic acid, glycerol residue with various concentrations, salt, and purple non-sulphur photosynthetic bacteria were put together into a 100 ml bottle which had been previously sterilized, then incubated for four weeks under the light of 40-watt bulb. The result showed that on the 28th day of fermentation, the produced acetic acid were 0.28, 1.85, and 0.2% (w/w) by using glycerine with the concentration of 0.5, 1.0, and 1.5% (w/w), respectively.

Pesticide residues in locally available cereals and vegetables

International Nuclear Information System (INIS)

Cunanan, S.A.; Santos, F.L.; Bonoan, L.S.

1976-03-01

Vegetable samples (pechay, cabbage, lettuce, green beans and tomatoes) bought from public markets in the Metro Manila area were analyzed for pesticide residues using gas chromatography. The samples analyzed in 1968-69 contained high levels of chlorinated pesticides such as DDT, Aldrin, Endrin, and Thiodan, while in the samples analyzed in January 1976, no chlorinated and organophosphate pesticides were detected. Cereal samples (rice, corn and sorghum) were obtained from the National Grains Authority and analyzed for pesticide residues and bromine residues. Total bromine residues was determined by neutron activation analysis. In most of the samples analyzed, the concentrations of pesticide residues were below the tolerance levels set by the FAO/WHO Committee on Pesticide Residues in Foods. An exception was one rice sample from Thailand, the bromine residue content (110ppm) of which exceeds the tolerance level of 50ppm

Effect of leaching residual methyl methacrylate concentrations on in vitro cytotoxicity of heat polymerized denture base acrylic resin processed with different polymerization cycles

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Canan Bural

2011-08-01

Full Text Available OBJECTIVES: Residual methyl methacrylate (MMA may leach from the acrylic resin denture bases and have adverse effects on the oral mucosa. This in vitro study evaluated and correlated the effect of the leaching residual MMA concentrations ([MMA]r on in vitro cytotoxicity of L-929 fibroblasts. MATERIAL AND METHODS: A total of 144 heat-polymerized acrylic resin specimens were fabricated using 4 different polymerization cycles: (1 at 74ºC for 9 h, (2 at 74ºC for 9 h and terminal boiling (at 100ºC for 30 min, (3 at 74ºC for 9 h and terminal boiling for 3 h, (4 at 74ºC for 30 min and terminal boiling for 30 min. Specimens were eluted in a complete cell culture medium at 37ºC for 1, 2, 5 and 7 days. [MMA]r in eluates was measured using high-performance liquid chromatography. In vitro cytotoxicity of eluates on L-929 fibroblasts was evaluated by means of cell proliferation using a tetrazolium salt XTT (sodium 3´-[1-phenyl-aminocarbonyl-3,4-tetrazolium]bis(4-methoxy-6-nitrobenzenesulphonic acid assay. Differences in [MMA]r of eluates and cell proliferation values between polymerization cycles were statistically analyzed by Kruskal-Wallis, Friedman and Dunn's multiple comparison tests. The correlation between [MMA]r of eluates and cell proliferation was analyzed by Pearson's correlation test (p<0.05. RESULTS: [MMA]r was significantly (p<0.001 higher in eluates of specimens polymerized with cycle without terminal boiling after elution of 1 and 2 days. Cell proliferation values for all cycles were significantly (p<0.01 lower in eluates of 1 day than those of 2 days. The correlation between [MMA]r and cell proliferation values was negative after all elution periods, showing significance (p<0.05 for elution of 1 and 2 days. MMA continued to leach from acrylic resin throughout 7 days and leaching concentrations markedly reduced after elution of 1 and 2 days. CONCLUSION: Due to reduction of leaching residual MMA concentrations, use of terminal boiling in

Residual stress in spin-cast polyurethane thin films

Energy Technology Data Exchange (ETDEWEB)

Zhang, Hong; Zhang, Li, E-mail: lizhang@mae.cuhk.edu.hk [Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin N.T., Hong Kong (China); Chow Yuk Ho Technology Centre for Innovative Medicine, The Chinese University of Hong Kong, Shatin N.T., Hong Kong (China)

2015-01-19

Residual stress is inevitable during spin-casting. Herein, we report a straightforward method to evaluate the residual stress in as-cast polyurethane thin films using area shrinkage measurement of films in floating state, which shows that the residual stress is independent of radial location on the substrate and decreased with decreasing film thickness below a critical value. We demonstrate that the residual stress is developed due to the solvent evaporation after vitrification during spin-casting and the polymer chains in thin films may undergo vitrification at an increased concentration. The buildup of residual stress in spin-cast polymer films provides an insight into the size effects on the nature of polymer thin films.

Release behavior of triazine residues in stabilised contaminated soils

International Nuclear Information System (INIS)

Ying, G.G.; Kookana, R.S.; Mallavarpu, M.

2005-01-01

This paper reports the release behavior of two triazines (atrazine and simazine) in stabilised soils from a pesticide-contaminated site in South Australia. The soils were contaminated with a range of pesticides, especially with triazine herbicides. With multiple extractions of each soil sample with deionised water (eight in total), 15% of atrazine and 4% of simazine residues were recovered, resulting in very high concentrations of the two herbicides in leachate. The presence of small fractions of surfactants was found to further enhance the release of the residues. Methanol content up to 10% did not substantially influence the concentration of simazine and atrazine released. The study demonstrated that while the stabilisation of contaminated soil with particulate activated carbon (5%) and cement mix (15%) was effective in locking the residues of some pesticides, it failed to immobilise triazine herbicides residues completely. Given the higher water solubility of these herbicides than other compounds more effective strategies to immobilise their residues is needed. - Stabilisation of contaminated soil with a mix of activated carbon and cement may fail to immobilise some contaminants like triazines

Endosulfan residues in fish from the MUDA rice agroecosystem

International Nuclear Information System (INIS)

Nashriyah Mat; Sabri Junoh; Nuriati Nurdin

2002-01-01

A study was carried out in the recycled and the non-recycled areas of the Muda rice agroecosystem to determine the residue level of endosulfan in rice field fish. Snakehead or haruan (Channa striata), climbing perch or puyu (Anabas testudineus), walking catfish or keli (Clariasspp.) and snakeskin gouramy or sepat siam (Trichogasterpectoralis) were sampled and the tissues analysed using Gas Liquid Chromatography. Endosulfan sulphate metabolite was a ubiquitous residue in all fish at levels ranging from 0.0065 μg/g to 0.9837 μg/g of tissue wet weight whilst α-isomer was detected at a much lower concentration followed by β-isomer. In Channa striata, endosulfan total residue (α+β+sulphate) was accumulated in fish tissues sampled at ACRBD4 (non-recycled) site followed by Blok 14 (recycled) site. Endosulfan residue concentration did not coincide with water recycling practice nor changes in EROD enzyme activity. (Author)

Observational assessment of the role of nocturnal residual-layer chemistry in determining daytime surface particulate nitrate concentrations

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G. Prabhakar

2017-12-01

Full Text Available This study discusses an analysis of combined airborne and ground observations of particulate nitrate (NO3−(p concentrations made during the wintertime DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically resolved observations relevant to Air Quality study at one of the most polluted cities in the United States – Fresno, CA – in the San Joaquin Valley (SJV and focuses on developing an understanding of the various processes that impact surface nitrate concentrations during pollution events. The results provide an explicit case-study illustration of how nighttime chemistry can influence daytime surface-level NO3−(p concentrations, complementing previous studies in the SJV. The observations exemplify the critical role that nocturnal chemical production of NO3−(p aloft in the residual layer (RL can play in determining daytime surface-level NO3−(p concentrations. Further, they indicate that nocturnal production of NO3−(p in the RL, along with daytime photochemical production, can contribute substantially to the buildup and sustaining of severe pollution episodes. The exceptionally shallow nocturnal boundary layer (NBL heights characteristic of wintertime pollution events in the SJV intensify the importance of nocturnal production aloft in the residual layer to daytime surface concentrations. The observations also demonstrate that dynamics within the RL can influence the early-morning vertical distribution of NO3−(p, despite low wintertime wind speeds. This overnight reshaping of the vertical distribution above the city plays an important role in determining the net impact of nocturnal chemical production on local and regional surface-level NO3−(p concentrations. Entrainment of clean free-tropospheric (FT air into the boundary layer in the afternoon is identified as an important process that reduces surface-level NO3−(p and limits buildup during pollution episodes. The influence of dry deposition of HNO

Toxicity and residual control of Plutella xylostella L. (Lepidoptera: Plutellidae with Bacillus thuringiensis Berliner and insecticides Toxicidade e controle residual de Plutella xylostella L. (Lepidoptera: Plutellidae com Bacillus thuringiensis Berliner e inseticidas

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Carla Pedroso de Moraes

2012-08-01

Full Text Available Plutella xylostella L. is the most important worldwide pest of cruciferous plants and indiscriminate use of insecticides has led to the resistance of the species to different groups. This research was conducted to compare the toxicity and persistence of two strains of Bacillus thuringiensis to P. xylostella larvae. Concentrations between 125 and 500g 100L-1 of water of the commercial products were evaluated and compared to the insect growth inhibitor diflubenzuron and to the neurotoxic pyrethroid deltamethrin. The efficacy of the insecticides was compared between treated plants kept indoor greenhouse and outdoor. Third instar larvae were more susceptible to B. thuringiensis than first instar ones. Agree and Dipel showed similar control rates of third instars until 10 days after treatment, but on the 15th day, Agree was significantly more efficient than Dipel. Both B. thuringiensis formulations showed a reduction in mortality after 10 days when the treated plants were exposed to natural weather conditions in comparison to the same treatments kept inside greenhouse. Dimilin (100g 100L-1 of water and deltamethrin (30ml of commercial product 100L-1 of water were not efficient to control third instar larvae of P. xylostella. This inefficiency cannot be attributed to a resistant population of P. xylostella since the larval population used in the experiments was not subjected to insecticide pressure, once the crop was organically cultivated all year round. The results showed that both formulations of B. thuringiensis are sound alternatives for the control of the diamondback moth in organically conducted cruciferous crops, considering the high residual control provided under subtropical weather conditions.Larvas de Plutella xylostella L. são as principais pragas de crucíferas cultivadas e o uso excessivo e indiscriminado de inseticidas tem levado a resistência da espécie para diferentes grupos de inseticidas. Este trabalho foi conduzido para

Matrix-Matching as an Improvement Strategy for the Detection of Pesticide Residues.

Science.gov (United States)

Giacinti, Géraldine; Raynaud, Christine; Capblancq, Sophie; Simon, Valérie

2016-05-01

More than 90% of the pesticides residues in apples are located in the peel. We developed a gas chromatography/ion trap tandem mass spectrometry method for investigating all detectable residues in the peel of 3 apple varieties. Sample preparation is based on the use of the Quick Easy Cheap Effective Rugged and Safe method on the whole fruit, the flesh, and the peel. Pesticide residues were quantified with solvent-matched and matrix-matched standards, by spiking apple sample extracts. Matrix effects dependent on the type of extract (fruit, flesh, or peel) and the apple variety were detected. The best data processing methods involved normalizing matrix effect rates by matrix-matched internal/external calibration. Boscalid, captan, chlorpyrifos, fludioxonil, and pyraclostrobin were the most frequently detected pesticides. However, their concentrations in the whole fruit were below European maximum residue levels. Despite negative matrix effects, the residues in peel were detected at concentrations up to 10 times higher than those in whole fruits. Consequently, other pesticide residues present at concentrations below the limit of quantification in the whole fruit were detected in the peel. © 2016 Institute of Food Technologists®

Recovery of sulfur from residue gases of low H/sub 2/S concentration

Energy Technology Data Exchange (ETDEWEB)

Bratzler, K; Doerges, A; Schlauer, J

1976-01-01

The Lucas process is intended for reduction of SO/sub 2/ and H/sub 2/S in Claus tail gas or other low-sulfur residue gases to levels below 200 ppm (H/sub 2/S only in traces). In the first stage, all sulfur compounds are burned to SO/sub 2/; in the second stage, a coke reactor reduces SO/sub 3/ and O/sub 2/; and in the third stage, the SO/sub 2/ is absorbed in an aqueous alkali phosphate solution. Concentrated SO/sub 2/ from regeneration of the solution is returned to the Claus plant, or can be catalystically reduced to elemental sulfur. The process was proven out in a semitechnical pilot plant, with satisfactory results as follows: sulfur recovery, 97 to 99.8%; energy consumption per 1,000 cu m feed gas, 2.6 to 3.7 kw-hr plus 860 to 930 MJ heating gas (however, 300 to 350 kg steam was generated); 0.15 kg chemicals; 0.7 to 1.5 kg coke; and a minimal amount of catalyst if sulfur is produced. Investment is only 60 to 80% of that in a 2-stage Claus process, with which the Lucas process is competitive.

HPLC identification of isoniazid residues in bovine milk

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Leite R.M.H.

2000-01-01

Full Text Available The high pressure liquid chromatography (HPLC was used for the identification of isoniazid (isonicotinic acid hydrazide in the milk of cattle treated with a dose of 25 mg/kg/day in alternated days. The effect of milk pasteurization on the isoniazid residue concentration was also studied. The drug excretion presented a cyclic variation, with higher levels in the first day after administration (aa, a mean of 1104.48µg/l, and a decrease two days aa, with a mean of 104.12µg/l. Four days after the last administration of the drug it was not possible to identify residues of isoniazid in the milk of treated animals. Body weight and milk yield influenced the amount of the excreted drug, and pasteurization decreased (mean 47.07% the concentration of isoniazid residue in milk.

Natural radioactivity in petroleum residues

International Nuclear Information System (INIS)

Gazineu, M.H.P.; Gazineu, M.H.P.; Hazin, C.A.; Hazin, C.A.

2006-01-01

The oil extraction and production industry generates several types of solid and liquid wastes. Scales, sludge and water are typical residues that can be found in such facilities and that can be contaminated with Naturally Occurring Radioactive Material (N.O.R.M.). As a result of oil processing, the natural radionuclides can be concentrated in such residues, forming the so called Technologically Enhanced Naturally Occurring Radioactive Material, or T.E.N.O.R.M.. Most of the radionuclides that appear in oil and gas streams belong to the 238 U and 232 Th natural series, besides 40 K. The present work was developed to determine the radionuclide content of scales and sludge generated during oil extraction and production operations. Emphasis was given to the quantification of 226 Ra, 228 Ra and 40 K since these radionuclides,are responsible for most of the external exposure in such facilities. Samples were taken from the P.E.T.R.O.B.R.A.S. unity in the State of Sergipe, in Northeastern Brazil. They were collected directly from the inner surface of water pipes and storage tanks, or from barrels stored in the waste storage area of the E and P unit. The activity concentrations for 226 Ra, 228 Ra and 40 K were determined by using an HP Ge gamma spectrometric system. The results showed concentrations ranging from 42.7 to 2,110.0 kBq/kg for 226 Ra, 40.5 to 1,550.0 kBq/kg for 228 Ra, and 20.6 to 186.6 kBq/kg for 40 K. The results highlight the importance of determining the activity concentration of those radionuclides in oil residues before deciding whether they should be stored or discarded to the environment. (authors)

Monitoring of Benomyl Residue in Mushroom Marketed in Hamadan City

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S. Abdi

2015-07-01

Full Text Available Introduction & Objective: Pesticide residues in environment and food have a negative impact on the health of living organisms. Therefore, this study was carried out for evaluation of benomyl residues in mushroom marketed in Hamadan city in 2014 using spectrophotometry. Materials & Methods: 10 specimens of mushroom were collected from greenhouses and market basket of Hamadan city. After preparation and processing the samples in the laboratory, be-nomyl residues in samples were determined using a spectrophotometric method in 3 replica-tions. All statistical analyses were performed using the SPSS statistical package. Results: The mean concentration of benomyl residues in samples were 5.90±0.75, 2.10± 0.487, 40.04±1.346, 0.32±0.044, 14.0±0.785, 1.54±0.304, 40.0±0.45, 0.87±0.055, 0.66± 0.032 and 49.60±0.303 µg kg-1 and more than the maximum residue limit (MRL provided by the World Health Organization (10 ppb. The results of the comparison of the mean concentration of pesticide residues among samples revealed significant differences in most of the samples (P<0.05. Conclusion: The results showed that mean concentrations of benomyl residues in mushroom samples were exceeding that of the MRL. Therefore, it is essential to impart proper education to the farming community about hazards involved in the overuse of toxic pesticides. Also, codification of laws and their enforcement and implementation of programs for the regular periodic monitoring of pesticide residues in foodstuffs especially in vegetables cultivated un-der greenhouse conditions at the national level to protect consumers’ health are recom-mended.(Sci J Hamadan Univ Med Sci 2015; 22 (2: 137-143

Control of residual carbon concentration in GaN high electron mobility transistor and realization of high-resistance GaN grown by metal-organic chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

He, X.G. [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China); Zhao, D.G., E-mail: dgzhao@red.semi.ac.cn [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China); Jiang, D.S.; Liu, Z.S.; Chen, P.; Le, L.C.; Yang, J.; Li, X.J. [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China); Zhang, S.M.; Zhu, J.J.; Wang, H.; Yang, H. [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215125 (China)

2014-08-01

GaN films were grown by metal-organic chemical vapor deposition (MOCVD) under various growth conditions. The influences of MOCVD growth parameters, i.e., growth pressure, ammonia (NH{sub 3}) flux, growth temperature, trimethyl-gallium flux and H{sub 2} flux, on residual carbon concentration ([C]) were systematically investigated. Secondary ion mass spectroscopy measurements show that [C] can be effectively modulated by growth conditions. Especially, it can increase by reducing growth pressure up to two orders of magnitude. High-resistance (HR) GaN epilayer with a resistivity over 1.0 × 10{sup 9} Ω·cm is achieved by reducing growth pressure. The mechanism of the formation of HR GaN epilayer is discussed. An Al{sub x}Ga{sub 1−x}N/GaN high electron mobility transistor structure with a HR GaN buffer layer and an additional low-carbon GaN channel layer is presented, exhibiting a high two dimensional electron gas mobility of 1815 cm{sup 2}/Vs. - Highlights: • Influence of MOCVD parameters on residual carbon concentration in GaN is studied. • GaN layer with a resistivity over 1 × 10{sup 9} Ω·cm is achieved by reducing growth pressure. • High electron mobility transistor (HEMT) structures were prepared. • Control of residual carbon content results in HEMT with high 2-D electron gas mobility.

Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa

Energy Technology Data Exchange (ETDEWEB)

Bouwman, H. [School for Environmental Sciences and Development, North-West University (Potchefstroom Campus), Private Bag X6001, Potchefstroom 2520 (South Africa)]. E-mail: drkhb@puk.ac.za; Sereda, B. [Agricultural Research Council, Plant Protection Research Institute, Private Bag X134 Queenswood, Pretoria 0121 (South Africa); Meinhardt, H.M. [South African Bureau of Standards, Testing and Conformity Services (Pty) Ltd, Private Bag X191, Pretoria 0001 (South Africa)

2006-12-15

DDT and pyrethroids were determined in 152 breast-milk samples from three towns in KwaZulu-Natal, South Africa, one of which had no need for DDT for malaria control. All compounds were found present in breast milk. Primiparae from one town had the highest mean {sigma}DDT whole milk levels (238.23 {mu}g/l), and multiparae from the same town had the highest means for permethrin (14.51 {mu}g/l), cyfluthrin (41.74 {mu}g/l), cypermethrin (4.24 {mu}g/l), deltamethrin (8.39 {mu}g/l), and {sigma}pyrethroid (31.5 {mu}g/l), most likely derived from agriculture. The ADI for DDT was only exceeded by infants from one town, but the ADI for pyrethroids was not exceeded. Since the ADI for DDT was recently reduced from 20 to 10 {mu}g/kg/bw, we suggest that this aspect be treated with concern. We therefore raise a concern based on toxicant interactions, due to the presence of four different pyrethroids and DDT. Breastfeeding however, remains safe under prevailing conditions. - The simultaneous presence of DDT and pyrethroid residues in breast milk raises the question of infant exposure and safety.

Isotopic tracer aided studies of fenvalerate residues in stored rice

International Nuclear Information System (INIS)

Varca, L.M.; Sanchez, T.E.; Magallona, E.D.

1990-01-01

Following application of 14 C-fenvalerate to milled rice and paddy rice at a concentration of 0.33 mg/kg, only insignificant losses were measured after 9 months. Distribution patterns in surface, methanol extractable and bound residues were studied. Paddy rice contained less extractable residues than milled rice, with the major part being found in the husk. Bound residues in both milled and paddy rice decreased also with length of storage; as much as 30% was found as bound residues after nine months. Cooking reduced the insecticide residues in milled rice by 33-40% and residues in paddy rice by 58%. (author). 8 refs, 1 fig., 4 tabs

Nutritional potential of post extraction residues and silage from ...

African Journals Online (AJOL)

Nutritional potential of post extraction residues and silage from leaves of five cassava varieties as feed for ruminants. ... Results indicated that processing reduced (P < 0.05) the inherent nutrients of cassava leaf residues produced after the extraction of protein concentrate from cassava leaves with crude protein (CP) content ...

Effect of cooking on enrofloxacin residues in chicken tissue.

Science.gov (United States)

Lolo, M; Pedreira, S; Miranda, J M; Vázquez, B I; Franco, C M; Cepeda, A; Fente, C

2006-10-01

The aim of this study was to determine the effect of different cooking processes (microwaving, roasting, boiling, grilling and frying) on naturally incurred enrofloxacin residues in chicken muscle. Enrofloxacin and its metabolite, ciprofloxacin, were analysed using a validated LC-MS method with limits of detection (LOD) and quantification (LOQ), respectively, of 2 and 5 ng g-1 quinolones in muscle samples. The method was shown to be linear over the range 5-500 ng g-1. Mean intra-day relative standard deviation (RSD) at a concentration of 50 ng g-1 (n = 6) was 6%; inter-day RSD was 12%. A recovery study demonstrated that 65-101%, of the drug and metabolite could be recovered from the tissue. The RSD with naturally incurred roasted chicken breast was 9.18% at a concentration of 11 +/- 1.01 ng g-1 (n = 6). In water, enrofloxacin remained stable for 3 h when heated at 100 degrees C. It was concluded that residue data from raw tissue are valid for estimation of consumer exposure to this drug, as well as the ADI calculations because cooking procedures did not affect enrofloxacin residues, which remained stable during heating. However, there was an apparent decrease in quinolone concentration in tissue because some was lost by exudation into the liquid used for cooking. Conversely, for a cooking procedure with water loss, there was an apparent increase in residue concentration.

Actinide recovery from pyrochemical residues

International Nuclear Information System (INIS)

Avens, L.R.; Clifton, D.G.; Vigil, A.R.

1984-01-01

A new process for recovery of plutonium and americium from pyrochemical waste has been demonstrated. It is based on chloride solution anion exchange at low acidity, which eliminates corrosive HCl fumes. Developmental experiments of the process flowsheet concentrated on molten salt extraction (MSE) residues and gave >95% plutonium and >90% americium recovery. The recovered plutonium contained 6 = from high chloride-low acid solution. Americium and other metals are washed from the ion exchange column with 1N HNO 3 -4.8M NaCl. The plutonium is recovered, after elution, via hydroxide precipitation, while the americium is recovered via NaHCO 3 precipitation. All filtrates from the process are discardable as low-level contaminated waste. Production-scale experiments are now in progress for MSE residues. Flow sheets for actinide recovery from electrorefining and direct oxide reduction residues are presented and discussed

Actinide recovery from pyrochemical residues

International Nuclear Information System (INIS)

Avens, L.R.; Clifton, D.G.; Vigil, A.R.

1985-05-01

We demonstrated a new process for recovering plutonium and americium from pyrochemical waste. The method is based on chloride solution anion exchange at low acidity, or acidity that eliminates corrosive HCl fumes. Developmental experiments of the process flow chart concentrated on molten salt extraction (MSE) residues and gave >95% plutonium and >90% americium recovery. The recovered plutonium contained 6 2- from high-chloride low-acid solution. Americium and other metals are washed from the ion exchange column with lN HNO 3 -4.8M NaCl. After elution, plutonium is recovered by hydroxide precipitation, and americium is recovered by NaHCO 3 precipitation. All filtrates from the process can be discardable as low-level contaminated waste. Production-scale experiments are in progress for MSE residues. Flow charts for actinide recovery from electro-refining and direct oxide reduction residues are presented and discussed

First report of the concentrations and implications of DDT residues in chicken eggs from a malaria-controlled area.

Science.gov (United States)

Bouwman, Hindrik; Bornman, Riana; van Dyk, Cobus; Barnhoorn, Irene

2015-10-01

In malaria-endemic areas, where DDT is still used for vector control by indoor residual spraying (IRS), the concentrations of DDT in human blood and breast milk are high, and there are indications of human health impacts. To identify the possible avenues of exposure reduction, we created the concept of a Total Homestead Environment Approach (THEA). THEA characterizes the interactions between DDT, humans, and the biota within and around homesteads. One dietary route of human exposure and uptake of DDT, namely, chicken egg consumption, has to our knowledge never been studied. The ΣDDT in eggs from a DDT-sprayed village ranged between 5200 and 48,000 ng/g wm (wet mass), with a median of 11,000 ng/g wm. On a lipid mass-basis (lm), the mean ΣDDT for eggs from the sprayed village was 100,000 ng/g lm. The maximum egg concentration observed was three orders of magnitude higher than the median. The acceptable daily intake (ADI) was not exceeded based on the consumption of three eggs per week for a 60 kg person. This equates to an intake of 0.089 g DDT per person per year. Chicken egg consumption is therefore a possible target for exposure reduction, probably best achieved by reducing the DDT concentrations in soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

Water leaching of titanium from ore flotation residue.

Science.gov (United States)

Jaworska, Malgorzata M; Guibal, Eric

2003-01-01

Copper ore tailings were tested for the stability of titanium submitted to water leaching in three different reactor systems (agitated vessel, bioreactor and percolated fixed-bed column). For each of these systems, titanium extraction did not exceed 1% of the available metal. Biomass removed from ore residue adsorbed a small part of the titanium with sorption capacities below 20-30 mg g(-1), but most of this biomass was sequestered in the ore residue. Oxygen and carbon dioxide concentrations were monitored and changes in concentration correlated with bacteria development at the initial stage of the process and to fungal development in the latter stages.

Environmental interpretation using insoluble residues within reef coral skeletons: problems, pitfalls, and preliminary results

Science.gov (United States)

Budd, Ann F.; Mann, Keith O.; Guzmán, Hector M.

1993-03-01

Insoluble residue concentrations have been measured within colonies of four massive reef corals from seven localities along the Caribbean coast of Panama to determine if detrital sediments, incorporated within the skeletal lattice during growth, record changes in sedimentation over the past twenty years. Amounts of resuspended sediment have increased to varying degrees at the seven localities over the past decades in response to increased deforestation in nearby terrestrial habitats. Preliminary results of correlation and regression analyses reveal few consistent temporal trends in the insoluble residue concentration. Analyses of variance suggest that amounts of insoluble residues, however, differ among environments within species, but that no consistent pattern of variation exists among species. D. strigosa and P. astreoides possess high concentrations at protected localities, S. siderea at localities with high amounts of resuspended sediment, and M. annularis at the least turbid localities. Little correlation exists between insoluble residue concentration and growth band width within species at each locality. Only in two more efficient suspension feeders ( S. siderea and D. strigosa) do weak negative correlations with growth band width exist overall. These results indicate that insoluble residue concentrations cannot be used unequivocally in environmental interpretation, until more is known about tissue damage, polyp behavior, and their effects on the incorporation of insolubles in the skeleton during growth in different coral species. Insoluble residue data are highly variable; therefore, large sample sizes and strong contrasts between environments are required to reveal significant trends.

Modelling of the long-term fate of pesticide residues in agricultural soils and their surface exchange with the atmosphere: Part II. Projected long-term fate of pesticide residues.

Science.gov (United States)

Scholtz, M T; Bidleman, T F

2007-05-01

In the first part of this paper, a simple coupled dynamic soil-atmosphere model for studying the gaseous exchange of pesticide soil residues with the atmosphere is described and evaluated by comparing model results with published measurements of pesticide concentrations in air and soil. In Part II, the model is used to study the concentration profiles of pesticide residues in both undisturbed and annually tilled agricultural soils. Future trends are estimated for the measured air and soil concentrations of lindane and six highly persistent pesticides (toxaphene, p,p'-DDE, dieldrin, cis- and trans-chlordane and trans-nonachlor) over a twenty-year period due to volatilization and leaching into the deeper soil. Wet deposition and particle associated pesticide deposition (that increase soil residue concentrations) and soil erosion, degradation in the soil (other than for lindane) and run-off in precipitation are not considered in this study. Estimates of the rain deposition fluxes are reported that show that, other than for lindane, net volatilization fluxes greatly exceed rain deposition fluxes. The model shows that the persistent pesticides studied are highly immobile in soil and that loss of these highly persistent residues from the soil is by volatilization rather than leaching into the deeper soil. The soil residue levels of these six pesticides are currently sources of net volatilization to the atmosphere and will remain so for many years. The maximum rate of volatilization from the soil was simulated by setting the atmospheric background concentration to zero; these simulations show that the rates of volatilization will not be significantly increased since soil resistance rather than the atmospheric concentration controls the volatilization rates. Annual tilling of the soils increases the volatilization loss to the atmosphere. Nonetheless, the model predicts that, if only air-soil exchange is considered, more than 76% of current persistent pesticide residues

Organochlorine residues in bat guano from nine Mexican caves, 1991

Science.gov (United States)

Clark, D.R.; Moreno-Valdez, A.; Mora, M.A.

1995-01-01

Samples of bat guano, primarily from Mexican free-tailed bats (Tadarida brasiliensis), were collected at nine bat roosts in caves in northern and eastern Mexico and analysed for organochlorine residues. DDE, the most abundant residue found in each cave, was highest (0.99 p.p.m. dry weight) at Ojuela Cave, Durango. Other studies of DDE in bat guano indicate that this concentration is too low to reflect harmful concentrations in the bats themselves. The DDE at Ojuela may represent either lingering residues from use of DDT years ago in the Ojuela area of perhaps depuration loss from migrant bats with summer maternity roost(s) in a DDE-contaminated area such as Carlsbad Cavern, New Mexico. Presence of o,p-DDT at Tio Bartolo Cave, Nuevo Leon, indicates recent use of DDT, but the concentration of this contaminant was low. Possible impacts on bat colonies of the organophosphorus and carbamate insecticides now in extensive use are unknown.

Numerical and Experimental Study on the Residual Stresses in the Nitrided Steel

Science.gov (United States)

Song, X.; Zhang, Zhi-Qian; Narayanaswamy, S.; Huang, Y. Z.; Zarinejad, M.

2016-09-01

In the present work, residual stresses distribution in the gas nitrided AISI 4140 sample has been studied using finite element (FE) simulation. The nitrogen concentration profile is obtained from the diffusion-controlled compound layer growth model, and nitrogen concentration controls the material volume change through phase transformation and lattice interstitials which results in residual stresses. Such model is validated through residual stress measurement technique—micro-ring-core method, which is applied to the nitriding process to obtain the residual stresses profiles in both the compound and diffusion layer. The numerical and experimental results are in good agreement with each other; they both indicate significant stress variation in the compound layer, which was not captured in previous research works due to the resolution limit of the traditional methods.

Toxicity and sublethal effects of six insecticides to last instar larvae and adults of the biocontrol agents Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) and Adalia bipunctata (L.) (Coleoptera: Coccinellidae).

Science.gov (United States)

Garzón, A; Medina, P; Amor, F; Viñuela, E; Budia, F

2015-08-01

To further develop Integrated Pest Management (IPM) strategies against crop pests, it is important to evaluate the effects of insecticides on biological control agents. Therefore, we tested the toxicity and sublethal effects (fecundity and fertility) of flonicamid, flubendiamide, metaflumizone, spirotetramat, sulfoxaflor and deltamethrin on the natural enemies Chrysoperla carnea and Adalia bipunctata. The side effects of the active ingredients of the insecticides were evaluated with residual contact tests for the larvae and adults of these predators in the laboratory. Flonicamid, flubendiamide, metaflumizone and spirotetramat were innocuous to last instar larvae and adults of C. carnea and A. bipunctata. Sulfoxaflor was slightly toxic to adults of C. carnea and was highly toxic to the L4 larvae of A. bipunctata. For A. bipunctata, sulfoxaflor and deltamethrin were the most damaging compounds with a cumulative larval mortality of 100%. Deltamethrin was also the most toxic compound to larvae and adults of C. carnea. In accordance with the results obtained, the compounds flonicamid, flubendiamide, metaflumizone and spirotetramat might be incorporated into IPM programs in combination with these natural enemies for the control of particular greenhouse pests. Nevertheless, the use of sulfoxaflor and deltamethrin in IPM strategies should be taken into consideration when releasing either of these biological control agents, due to the toxic behavior observed under laboratory conditions. The need for developing sustainable approaches to combine the use of these insecticides and natural enemies within an IPM framework is discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chlortetracycline and Oxytetracycline Residues in Poultry Tissues and Eggs

Science.gov (United States)

Meredith, W. E.; Weiser, H. H.; Winter, A. R.

1965-01-01

A pad-plate method of assaying residual amounts of chlortetracycline (CTC) and oxytetracycline (OTC) using Bacillus cereus 213 was used to determine amounts of antibiotic left in tissues and eggs of poultry fed 1,000 and 200 ppm of CTC and OTC in basal feed mixtures. The effects of various methods of cooking the tissues and eggs and the potentiating effect of terephthalic acid (TPA) were studied. It was found that normal methods of roasting, frying, and autoclaving poultry tissue destroyed all residual CTC and OTC, even with the potentiating effect of TPA. The largest amounts of residual antibiotic were found in the liver, then breast, and then thigh tissue when assayed for CTC. Tissue assays for CTC revealed that it was not taken up as extensively as CTC and the largest amounts were found in the liver, then breast. OTC residue was seldom found in the thigh tissue. Terephthalic acid in 0.5% concentration increased the concentration found in all cases. Cooking by poaching and scrambling eggs did not destroy the antibiotic in all cases. PMID:14264853

Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues.

Science.gov (United States)

Leili, Mostafa; Pirmoghani, Amin; Samadi, Mohammad Taghi; Shokoohi, Reza; Roshanaei, Ghodratollah; Poormohammadi, Ali

2016-11-01

The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption.

Pesticide residue concentration in soil following conventional and Low-Input Crop Management in a Mediterranean agro-ecosystem, in Central Greece

Energy Technology Data Exchange (ETDEWEB)

Karasali, Helen, E-mail: e.karassali@bpi.gr [Laboratory of Chemical Control of Pesticides, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece); Marousopoulou, Anna [Laboratory of Chemical Control of Pesticides, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece); Machera, Kyriaki, E-mail: k.machera@bpi.gr [Laboratory of Pesticides Toxicology, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece)

2016-01-15

The present study was focused on the comparative evaluation of pesticide residues, determined in soil samples from Kopaida region, Greece before and after the implementation of Low-Input Crop Management (LCM) protocols. LCM has been suggested as an environmental friendly plant protection approach to be applied on crops growing in vulnerable to pollution ecosystems, with special focus on the site specific problems. In the case of the specific pilot area, the vulnerability was mainly related to the pollution of water bodies from agrochemicals attributed to diffuse pollution primarily from herbicides and secondarily from insecticides. A total of sixty-six soil samples, were collected and analyzed during a three-year monitoring study and the results of the determined pesticide residues were considered for the impact evaluation of applied plant protection methodology. The LCM was developed and applied in the main crops growing in the pilot area i.e. cotton, maize and industrial tomato. Herbicides active ingredients such as ethalfluralin, trifluralin, pendimethalin, S-metolachlor and fluometuron were detected in most samples at various concentrations. Ethalfluralin, which was the active ingredient present in the majority of the samples ranged from 0.01 μg g{sup −1} to 0.26 μg g{sup −1} soil dry weight. However, the amount of herbicides measured after the implementation of LCM for two cropping periods, was reduced by more than 75% in all cases. The method of analysis was based on the simultaneous extraction of the target compounds by mechanical shaking, followed by liquid chromatography mass spectrometric and gas chromatography electron capture (LC–MS/MS and GC–ECD) analysis. - Highlights: • Effect of Low Input Crop Management (LCM) in a vulnerable to pollution ecosystem. • LCM resulted in herbicide residues reduction in the range of 75 and 100% in all cases. • Conventional practices resulted in increased herbicide residues up to 18%. • Anthropogenic

Laboratory studies of the properties of in-situ burn residues: chemical composition of residues

International Nuclear Information System (INIS)

Trudel, B.K.; Buist, I.A.; Schatzke, D.; Aurand, D.

1996-01-01

The chemical composition of the residue from small-scale burns of thick oil slicks was studied. The objective was to describe the changes in chemical composition in oils burning on water and to determine how these changes were influenced by the condition of the burn. Small-scale test burns involved burning 40-cm diameter pools of oil on water. A range of eight oil types including seven crude oils and an automotive diesel were burned. For each oil, slicks of fresh oil of three different thicknesses were tested. Two of the oils were tested before and after weathering. Results showed that the composition of the residue differed greatly from the parent oil. Asphaltenes, high-boiling-point aromatics and resins remained concentrated in the burn residue. The burning of slicks appeared to remove most of the lower-molecular weight aromatic hydrocarbons which included the more toxic and more bioavailable components of the crude oils. 11 refs., 6 tabs

Multiple cis-acting elements involved in up-regulation of a cytochrome P450 gene conferring resistance to deltamethrin in smal brown planthopper, Laodelphax striatellus (Fallén).

Science.gov (United States)

Pu, Jian; Sun, Haina; Wang, Jinda; Wu, Min; Wang, Kangxu; Denholm, Ian; Han, Zhaojun

2016-11-01

As well as arising from single point mutations in binding sites or detoxifying enzymes, it is likely that insecticide resistance mechanisms are frequently controlled by multiple genetic factors, resulting in resistance being inherited as a quantitative trait. However, empirical evidence for this is still rare. Here we analyse the causes of up-regulation of CYP6FU1, a monoxygenase implicated in resistance to deltamethrin in the rice pest Laodelphax striatellus. The 5'-flanking region of this gene was cloned and sequenced from individuals of a susceptible and a resistant strain. A luminescent reporter assay was used to evaluate different 5'-flanking regions and their fragments for promoter activity. Mutations enhancing promoter activity in various fragments were characterized, singly and in combination, by site mutation recovery. Nucleotide diversity in flanking sequences was greatly reduced in deltamethrin-resistant insects compared to susceptible ones. Phylogenetic sequence analysis found that CYP6FU1 had five different types of 5'-flanking region. All five types were present in a susceptible strain but only a single type showing the highest promoter activity was present in a resistant strain. Four cis-acting elements were identified whose influence on up-regulation was much more pronounced in combination than when present singly. Of these, two were new transcription factor (TF) binding sites produced by mutations, another one was also a new TF binding site alternated from an existing one, and the fourth was a unique transcription start site. These results demonstrate that multiple cis-acting elements are involved in up-regulating CYP6FU1 to generate a resistance phenotype. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

Directory of Open Access Journals (Sweden)

Zhen-hua Zhao

2016-10-01

Full Text Available The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl (PCB congeners in water and sediment were investigated in summer (July and autumn (September in the Chahe River, in Nanjing, China. The residual concentrations of tri-chlorobiphenyls (tri-CBs, PCB 18 and tetra-CBs (PCB 52 in water were significantly higher than those of penta-CBs to deca-CBs, and the average residual concentration of ∑PCBs (sum of 14 PCB congeners in summer was about six times higher than in autumn. However, the residues in sediment did not change significantly. Redundancy analysis (RDA indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and sediment. The overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in water. The highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78% and 67%, respectively, and those induced by a lake-type watercourse were 36% and 70%, respectively. The watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order: the natural ecological watercourse, vertical concrete watercourse, and vegetation-type riprap watercourse. However, they were ranked by residual ∑PCBs concentrations in sediment in the following descending order: the vertical concrete watercourse, vegetation-type riprap watercourse, and natural ecological watercourse.

A manual for implementing residual radioactive material guidelines

International Nuclear Information System (INIS)

Gilbert, T.L.; Yu, C.; Yuan, Y.C.; Zielen, A.J.; Jusko, M.J.; Wallo, A. III; Argonne National Lab., IL; Dames and Moore, West Valley, NY; Argonne National Lab., IL; USDOE Assistant Secretary for Nuclear Energy, Washington, DC

1989-06-01

This manual presents information for implementing US Department of Energy (DOE) guidelines for residual radioactive material at sites identified by the Formerly Utilized Sites Remedial Action Program (FUSRAP) and the Surplus Facilities Management Program (SFMP). It describes the analysis and models used to derive site-specific guidelines for allowable residual concentrations of radionuclides in soil and the design and use of the RESRAD computer code for calculating guideline values. It also describes procedures for implementing DOE policy for reducing residual radioactivity to levels that are as low as reasonably achievable. 36 refs., 16 figs, 22 tabs

Clean-up of aqueous acetone vegetable extracts by solid-matrix partition for pyrethroid residue determination by gas chromatography-electron-capture detection.

Science.gov (United States)

Di Muccio, A; Barbini, D A; Generali, T; Pelosi, P; Ausili, A; Vergori, F; Camoni, I

1997-03-21

Disposable, ready-to-use cartridges filled with macroporous diatomaceous material are used to carry out a partition clean-up that, in a single step, is capable of transferring pesticide residues from aqueous acetone extracts into light petroleum-dichloromethane (75:25, v/v). This procedure takes the place of some functions (such as separatory-funnel partition, drying over anhydrous sodium sulphate and partial adsorption clean-up) usually performed by separate steps in classical schemes. Fourteen pyrethroid pesticides, including tefluthrin, tetramethrin, cyphenothrin, cyfluthrin, flucythrinate, tau-fluvalinate, deltamethrin, bioallethrin, fenpropathrin, lambda-cyhalothrin, permethrin, alpha-cypermethrin, esfenvalerate and tralomethrin were determined using the described procedure with satisfactory recoveries for most of them, at spiking levels ranging from 0.08 to 0.82 mg/kg for the different compounds. Crops subjected to the described procedure included strawberry, apple, and orange gave extracts containing a mass of co-extractives that was between 5 and 30 mg. Compared with classical schemes, the described procedure is simple, less labour intensive, allows parallel handling of several extracts and does not require the preparation and maintenance of equipment. Troublesome emulsions such as those frequently observed in separation funnel partitioning do not occur.

Residues of Organochlorinated Pesticides in Soil from Tomato ...

African Journals Online (AJOL)

This work presents the concentrations of five pesticide residues, lindane, chlorpyrifos, endosulfan, p, p'-DDE and p, p'-DDD in soil samples collected from tomato fields in Ngarenanyuki, Tanzania. Endosulfan sulphate was detected in 100 % of the sample analysed with mean concentration of 0.2407 mg/kg dw. Chlorpyrifos ...

Influence of organic waste and residue mud additions on chemical, physical and microbial properties of bauxite residue sand.

Science.gov (United States)

Jones, Benjamin E H; Haynes, Richard J; Phillips, Ian R

2011-02-01

In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tone of alumina produced, about 2 tones of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation. Samples of freshly deposited residue sand were collected from Alcoa's Kwinana refinery. Samples were treated with phosphogypsum (2% v/v), incubated, and leached. A laboratory experiment was then set up in which the two organic wastes were applied at 0 or the equivalent to 60 tones ha(-1) in combination with residue mud added at rates of 0%, 10% and 20% v/v. Samples were incubated for 8 weeks, after which, key chemical, physical and microbial properties of the residue sand were measured along with seed germination. Additions of residue mud increased exchangeable Na(+), ESP and the pH, and HCO (3) (-) and Na(+) concentrations in saturation paste extracts. Additions of biosolids and poultry manure increased concentrations of extractable P, NH (4) (+) , K, Mg, Cu, Zn, Mn and Fe. Addition of residue mud, in combination with organic wastes, caused a marked decrease in macroporosity and a concomitant increase in mesoporosity, available water holding capacity and the quantity of water held at field capacity. With increasing residue mud additions, the percentage of sample present as sand particles (2 mm diameter) increased; greatest aggregation occurred where a combination of residue mud and poultry manure were added. Stability of aggregates, as measured by

Use of electroencephalography (EEG) to assess CNS changes produced by pesticides with different modes of action: Effects of permethrin, deltamethrin, fipronil, imidacloprid, carbaryl, and triadimefon

Energy Technology Data Exchange (ETDEWEB)

Freeborn, Danielle L., E-mail: Freeborn.danielle@epa.gov; McDaniel, Katherine L., E-mail: McDaniel.kathy@epa.gov; Moser, Virginia C., E-mail: Moser.ginger@epa.gov; Herr, David W., E-mail: Herr.david@epa.gov

2015-01-15

The electroencephalogram (EEG) is an apical measure, capable of detecting changes in brain neuronal activity produced by internal or external stimuli. We assessed whether pesticides with different modes of action produced different changes in the EEG of adult male Long–Evans rats. The EEG was recorded using two montages (visual cortex referenced to the cerebellum and to the frontal cortex) in unrestrained rats at the time of peak behavioral effects. Pesticides included: permethrin and deltamethrin (Type I and Type II pyrethroids; 2 h), fipronil (single and repeated doses; phenylpyrazole; 6 h), imidacloprid (neonicotinoid; 2 h), carbaryl (carbamate; 0.5 h), and triadimefon (triazole; 1 h), using dosages that produced approximately an ED{sub 30} or an ED{sub 50}–ED{sub 80} change in motor activity. Permethrin (43, 100 mg/kg) increased amplitudes or areas (delta, alpha, or gamma bands) in the EEG. Deltamethrin (2.5, 5.5 mg/kg) reduced the amplitudes or areas of the delta, theta, alpha, beta, and gamma bands, but the changes were not dose-related. A single treatment with fipronil (25, 50 mg/kg, but not 5, 10 mg/kg) decreased gamma band area. Additional changes in the delta, theta, and gamma bands were observed when fipronil (5, 10 mg/kg) was administered for 14 days. Imidacloprid (50, 100 mg/kg) did not alter the EEG. Carbaryl (10, 50 mg/kg) decreased theta area, and decreased delta and increased beta frequency. Triadimefon (75, 150 mg/kg) produced minimal changes in the EEG. The results show that the EEG is affected differently by approximately equipotent doses of pesticides with different modes of action. - Highlights: • Pesticides with different modes of action have different effects on in vivo rodent EEG. • The EEG was also changed differently after single vs. repeated treatment with fipronil. • The data suggest that EEG may be used as an apical measure for detecting chemical effects on the central nervous system.

Use of electroencephalography (EEG) to assess CNS changes produced by pesticides with different modes of action: Effects of permethrin, deltamethrin, fipronil, imidacloprid, carbaryl, and triadimefon

International Nuclear Information System (INIS)

Freeborn, Danielle L.; McDaniel, Katherine L.; Moser, Virginia C.; Herr, David W.

2015-01-01

The electroencephalogram (EEG) is an apical measure, capable of detecting changes in brain neuronal activity produced by internal or external stimuli. We assessed whether pesticides with different modes of action produced different changes in the EEG of adult male Long–Evans rats. The EEG was recorded using two montages (visual cortex referenced to the cerebellum and to the frontal cortex) in unrestrained rats at the time of peak behavioral effects. Pesticides included: permethrin and deltamethrin (Type I and Type II pyrethroids; 2 h), fipronil (single and repeated doses; phenylpyrazole; 6 h), imidacloprid (neonicotinoid; 2 h), carbaryl (carbamate; 0.5 h), and triadimefon (triazole; 1 h), using dosages that produced approximately an ED 30 or an ED 50 –ED 80 change in motor activity. Permethrin (43, 100 mg/kg) increased amplitudes or areas (delta, alpha, or gamma bands) in the EEG. Deltamethrin (2.5, 5.5 mg/kg) reduced the amplitudes or areas of the delta, theta, alpha, beta, and gamma bands, but the changes were not dose-related. A single treatment with fipronil (25, 50 mg/kg, but not 5, 10 mg/kg) decreased gamma band area. Additional changes in the delta, theta, and gamma bands were observed when fipronil (5, 10 mg/kg) was administered for 14 days. Imidacloprid (50, 100 mg/kg) did not alter the EEG. Carbaryl (10, 50 mg/kg) decreased theta area, and decreased delta and increased beta frequency. Triadimefon (75, 150 mg/kg) produced minimal changes in the EEG. The results show that the EEG is affected differently by approximately equipotent doses of pesticides with different modes of action. - Highlights: • Pesticides with different modes of action have different effects on in vivo rodent EEG. • The EEG was also changed differently after single vs. repeated treatment with fipronil. • The data suggest that EEG may be used as an apical measure for detecting chemical effects on the central nervous system

Residual nilpotence and residual solubility of groups

International Nuclear Information System (INIS)

Mikhailov, R V

2005-01-01

The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

Environmental toxicity and radioactivity assessment of a titanium-processing residue with potential for environmental use.

Science.gov (United States)

Wendling, Laura A; Binet, Monique T; Yuan, Zheng; Gissi, Francesca; Koppel, Darren J; Adams, Merrin S

2013-07-01

Thorough examination of the physicochemical characteristics of a Ti-processing residue was undertaken, including mineralogical, geochemical, and radiochemical characterization, and an investigation of the environmental toxicity of soft-water leachate generated from the residue. Concentrations of most metals measured in the leachate were low; thus, the residue is unlikely to leach high levels of potentially toxic elements on exposure to low-ionic strength natural waters. Relative to stringent ecosystem health-based guidelines, only chromium concentrations in the leachate exceeded guideline concentrations for 95% species protection; however, sulfate was present at concentrations known to cause toxicity. It is likely that the high concentration of calcium and extreme water hardness of the leachate reduced the bioavailability of some elements. Geochemical modeling of the leachate indicated that calcium and sulfate concentrations were largely controlled by gypsum mineral dissolution. The leachate was not toxic to the microalga Chlorella sp., the cladoceran Ceriodaphnia dubia, or the estuarine bacterium Vibrio fischeri. The Ti-processing residue exhibited an absorbed dose rate of 186 nGy/h, equivalent to an annual dose of 1.63 mGy and an annual effective dose of 0.326 mGy. In summary, the results indicate that the Ti-processing residue examined is suitable for productive use as an environmental amendment following 10 to 100 times dilution to ameliorate potential toxic effects due to chromium or sulfate. Copyright © 2013 SETAC.

Removal of heavy metals from aqueous solution by Carrot residues

International Nuclear Information System (INIS)

Eslamzadeh, T.; Nasernejad, B.; Bonakdar Pour, B.; Zamani, A.; Esmaail-Beygi, M.

2004-01-01

The removal of Copper(II), Zinc(II), and Chromium (III) from wastewater by carrot residues was investigated to evaluate cation exchange capacity. The effects of solution P H and co-ions were studied in batch experiments. Adsorption equilibria were initially rapidly established, and then decreased markedly after 10 min. Column experiments were carried out in a glass column filled with carrot residues to evaluate the metal removal capacity. The influences of the feed concentration and feed rate were also studied in order to compare the dynamic capacity for metal binding in different feed concentrations

Organochlorine residues in harp seals, Phoca groenlandica, from the Gulf of St. Lawrence and Hudson Strait: An evaluation of contaminant concentrations and burdens

Energy Technology Data Exchange (ETDEWEB)

Beck, G.G.; Smith, T.G. (Dept. of Fisheries and Oceans, Nanaimo, BC (Canada)); Addison, R.F. (Dept. of Fisheries and Oceans, Sidney, BC (Canada))

1994-01-01

Organochlorine contaminant concentrations and burdens were evaluated in blubber samples from 50 harp seals (Phoca groenlandica) obtained from the estuary and northern Gulf of St. Lawrence and Hudson Strait, Canada between December 1988 and December 1989. The concentration and burden of polychlorinated biphenyls (PCBs) increased significantly during the winter months for males occupying the St. Lawrence estuary. The potential for rapid accumulation of contaminants in the estuary was also observed among females: nine postpartum females (1 month after weaning) had higher organochlorine levels than prepartum females from the same location. The lowest observed contaminant concentrations and burdens were in seals from Hudson Strait in autumn. In winter specimens, males had DDT and PCB concentrations about 4 and 2 times as great, respectively, as females of similar age distribution and collection date. Congeners with IUPAC Nos. 138 and 153 accounted for more than 50% of total identifiable PCBs, which is consistent with their prevalence in other marine biota. The concentration of PCBs has declined and the percent p,p'-DDE of total DDT has increased between 1982 and the present study. Unlike the beluga whale (Delphinapterus leucas), harp seals occupy the more polluted waters of the estuary only seasonally, and this may account for their lower residue concentrations. 59 refs., 1 fig., 5 tabs.

Obtention of ceramic pigments with residue from electroplating

International Nuclear Information System (INIS)

Boss, A.; Kniess, C.T.; Aguiar, B.M. de; Prates, P.B.; Milanez, K.

2011-01-01

The incorporation of industrial residues in industrial processes opens up new business opportunities and reduces the volume of extraction of raw materials, preserving natural resources, which are limited. An important residue is the mud from galvanic industry, consisting of alkali and transition metals. According to NBR 10004/2004, this residue can be classified as Class I (hazardous), depending on the concentration of metals present in the mud. This paper proposes a method for reusing the residue from electroplating in ceramic pigments. The characterization of residual plating was obtained by chemical analysis, mineralogical analysis and pH measurements. The electroplating waste was incorporated in different percentages on a standard pigment formula of industrial ceramic, consisting mainly of Zn, Fe and Cr. The obtained pigments were applied in ceramic glazes to colorimetric and visual analysis, which showed good results with the addition of up to 15% of industrial waste. (author)

Residual Isocyanates in Medical Devices and Products: A Qualitative and Quantitative Assessment

Directory of Open Access Journals (Sweden)

Gillian Franklin

2016-01-01

Full Text Available We conducted a pilot qualitative and quantitative assessment of residual isocyanates and their potential initial exposures in neonates, as little is known about their contact effect. After a neonatal intensive care unit (NICU stockroom inventory, polyurethane (PU and PU foam (PUF devices and products were qualitatively evaluated for residual isocyanates using Surface SWYPE ™ . Those containing isocyanates were quantitatively tested for methylene diphenyl diisocyanate (MDI species, using UPLC-UV-MS/MS method. Ten of 37 products and devices tested, indicated both free and bound residual surface isocyanates; PU/PUF pieces contained aromatic isocyanates; one product contained aliphatic isocyanates. Overall, quantified mean MDI concentrations were low (4,4‘-MDI = 0.52 to 140.1 pg/mg and (2,4‘-MDI = 0.01 to 4.48 pg/mg. The 4,4‘-MDI species had the highest measured concentration (280 pg/mg. Commonly used medical devices/products contain low, but measurable concentrations of residual isocyanates. Quantifying other isocyanate species and neonatal skin exposure to isocyanates from these devices and products requires further investigation.

Addition of an organic amendment and/or residue mud to bauxite residue sand in order to improve its properties as a growth medium.

Science.gov (United States)

Jones, B E H; Haynes, R J; Phillips, I R

2012-03-01

The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated

Analysis and characterization of plutonium in pyrochemical salt residues

International Nuclear Information System (INIS)

Haschke, John M.; Phillips, Alan G.

2000-01-01

Quantitative measurement of hydrogen produced during salt-catalyzed hydrolysis of plutonium in pyrochemical salt residues show that the metal is present in concentrations of 10 ± 5 mass%. The analytical method is based on stoichiometric reaction of metal with water to form plutonium monoxide monohydride (PuOH) and hydrogen. Results of a kinetic model developed to describe the observed time dependence of the hydrolysis rate shows that metal is present predominately as particles with essentially spherical geometries and diameters near 1 mm. The presence of smaller metallic particles cannot be verified or excluded. Plutonium concentrations measured for residues stored in different configurations suggest that a sizable fraction of the metal has oxidized during storage. Application of the hydrolysis method in determining concentrations and dimensions of metallic plutonium in other nuclear waste forms is proposed

Tratamentos focais e totais com inseticidas de ação residual para o controle de Triatoma brasiliensis e Triatoma pseudomaculata no Nordeste brasileiro Focal and total residual insecticide spraying to control Triatoma brasiliensis and Triatoma pseudomaculata in Northeast Brazil

Directory of Open Access Journals (Sweden)

Alfredo M. Oliveira Filho

2000-01-01

Full Text Available Para controle eficiente dos triatomíneos Triatoma brasiliensis e Triatoma pseudomaculata, foi feito um ensaio de campo em Boa Viagem, Ceará, de modo a comparar a borrifação convencional versus tratamento focal com deltametrina 5% SC, dose 25 mg i.a./m² e o organofosforado malation lenta liberação 8.3% SR, dose 2g i.a./m². O ensaio incluiu aleatoriamente 1.541 casas, separadas em quatro grupos. Em dois deles foi aplicada borrifação focal ­ tratamento PT com deltametrina dentro das casas e no peridomicílio e PL que recebeu malation lenta liberação nas mesmas circunstâncias. Os outros dois tiveram tratamento convencional, isto é, aplicação total ­ PT com deltametrina no intra e peridomicílio e PL, tratado com deltametrina dentro das casas e malation lenta liberação no peridomicílio. As avaliações entomológicas aos 6 e 12 meses pós-tratamentos mostraram melhor resultado para o tratamento misto, grupo PL, provavelmente em decorrência da boa performance do piretróide dentro das casas e da formulação de lenta liberação nas condições hostis do peridomicílio. Os abrigos dos animais domésticos sofreram modificações ao longo do ano, colaborando com a redução da performance dos inseticidas no peridomicílio.To efficiently control the triatomines Triatoma brasiliensis and Triatoma pseudomaculata, a field trial was performed to compare conventional versus focal spraying of deltamethrin 5% SC at 25 mg a.i./m² and the slow-release organophosphate malathion 8.3% SR at 2g a.i./m². The assay took place in the county of Boa Viagem, Ceará State, with 1541 households, randomly separated into 4 groups. Two of them received focal spraying: PT, treated with deltamethrin indoors and in the peridomicile, and PL, which received slow-release malathion in the same circumstances. The other groups received conventional, i.e., total application: PT with deltamethrin in the intra- and peridomicile, and PL, which was treated with

Influence of turkey meat on residual nitrite in cured meat products.

Science.gov (United States)

Kilic, B; Cassens, R G; Borchert, L L

2001-02-01

A response surface experimental design was employed to estimate residual nitrite level at various initial nitrite concentrations, percent turkey meat in the formula, and heat quantity (F) values using a typical wiener as the test system. Pork and mechanically separated turkey were used as the meat ingredients. Residual nitrite and pH were measured at day 1, 7 days, 14 days, and 49 days after processing. Protein, fat, salt, moisture, and CIE (L*a*b*) color values were also determined. Results showed that the effect of turkey meat on residual nitrite level was significant (P meat in the formula resulted in lower residual nitrite levels at a fixed pH. The residual nitrite level was initially proportional to initial nitrite concentration, but it became a nonsignificant factor during longer storage time. Differences in heat quantity had a significant effect (P nitrite level initially. Greater heat quantity decreased residual nitrite level in finished cured meat products at a fixed pH. However, this effect became nonsignificant during longer storage. Reduction of residual nitrite in wieners because of turkey meat addition at a fixed pH was due to characteristics of the turkey tissue, but the mechanism of action remains unknown. It was also established that commercial wieners had a higher pH if poultry meat was included in the formulation.

Construction of a predictive model for concentration of nickel and vanadium in vacuum residues of crude oils using artificial neural networks and LIBS.

Science.gov (United States)

Tarazona, José L; Guerrero, Jáder; Cabanzo, Rafael; Mejía-Ospino, E

2012-03-01

A predictive model to determine the concentration of nickel and vanadium in vacuum residues of Colombian crude oils using laser-induced breakdown spectroscopy (LIBS) and artificial neural networks (ANNs) with nodes distributed in multiple layers (multilayer perceptron) is presented. ANN inputs are intensity values in the vicinity of the emission lines 300.248, 301.200 and 305.081 nm of the Ni(I), and 309.310, 310.229, and 311.070 nm of the V(II). The effects of varying number of nodes and the initial weights and biases in the ANNs were systematically explored. Average relative error of calibration/prediction (REC/REP) and average relative standard deviation (RSD) metrics were used to evaluate the performance of the ANN in the prediction of concentrations of two elements studied here. © 2012 Optical Society of America

Leaching Behavior of Circulating Fluidised Bed MSWI Air Pollution Control Residue in Washing Process

Directory of Open Access Journals (Sweden)

Zhiliang Chen

2016-09-01

Full Text Available In this study, air pollution control (APC residue is conducted with water washing process to reduce its chloride content. A novel electrical conductivily (EC measurement method is proposed to monitor the dynamic change of chloride concentrations in leachate as well as the chloride content of the residue. The method equally applies to various washing processes with different washing time, liquid/solid ratio and washing frequency. The results show that washing effectively extracts chloride salts from APC residues, including those from circulating fluidized bed (CFB municipal solid waste incineration (MSWI. The most appropriate liquid/solid ratio and washing time in the first washing are found to be around 4 L water per kg of APC residue and 30 min, respectively, and washing twice is required to obtain maximum dissolution. The pH value is the major controlling factor of the heavy metals speciation in leachate, while chloride concentration also affects the speciation of Cd. Water washing causes no perceptible transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs from the APC residue to leachate. The chloride concentration is strongly related with electrical conductivity (EC, as well as with the concentrations of calcium, sodium and potassium of washing water. Their regression analyses specify that soluble chloride salts and EC could act as an indirect indicator to monitor the change of chloride concentration and remaining chloride content, thus, contributing to the selection of the optimal washing conditions.

Residue pattern of polycyclic aromatic hydrocarbons during green tea manufacturing and their transfer rates during tea brewing.

Science.gov (United States)

Gao, Guanwei; Chen, Hongping; Liu, Pingxiang; Hao, Zhenxia; Ma, Guicen; Chai, Yunfeng; Wang, Chen; Lu, Chengyin

2017-06-01

Residues of polycyclic aromatic hydrocarbons (PAHs) in green tea and tea infusion were determined using gas chromatography-tandem mass spectrometry to study their dissipation pattern during green tea processing and infusion. Concentration and evaporation of PAHs during tea processing were the key factors affecting PAH residue content in product intermediates and in green tea. PAH residues in tea leaves increased by 2.4-3.1 times during the manufacture of green tea using the electric heating model. After correction to dry weight, PAH residue concentrations decreased by 33.5-48.4% during green tea processing because of PAH evaporation. Moreover, spreading and drying reduced PAH concentrations. The transfer rates of PAH residues from green tea to infusion varied from 4.6% to 7.2%, and PAH leaching was higher in the first infusion than in the second infusion. These results are useful for assessing exposure to PAHs from green tea and in formulating controls for the maximum residue level of PAHs in green tea.

Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings.

Science.gov (United States)

Larsen, Julie D; Nielsen, Steen M; Scheutz, Charlotte

2017-11-01

Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during the resting period. As the resting period proceeded, atmospheric air re-entered the pore space at all depth levels. The methane (CH 4 ) concentration was at its highest during the first part of the resting period, and then declined as the sludge residue became more dewatered and thereby aerated. In the pore space, the concentration of CH 4 often exceeded the concentration of carbon dioxide (CO 2 ). However, the total emission of CO 2 from the surface of the sludge residue exceeded the total emission of CH 4 , suggesting that CO 2 was mainly produced in the layer of newly applied sludge and/or that CO 2 was emitted from the sludge residue more readily compared to CH 4 .

Effect of irradiation on oxytetracycline residues in poultry meat

Energy Technology Data Exchange (ETDEWEB)

Mazurowski, P [Warsaw Agricultural University, Faculty of Veterinary Medicine, Department of Food Hygiene, Warsaw (Poland)

1994-12-31

The purpose of the study was an evaluation of the effect of ionizing radiation on detection of oxytetracycline residues in poultry meat. Oxytetracycline was chosen as a representative of tetracyclines which are often applied in poultry for therapeutical reasons. The experiment was conducted using both broiler meat treated by oxytetracycline and slurry of broiler meat containing appropriate concentration of this antibiotic. A traditional microbiological method for determination of antibiotics antimicrobial activity was used. A significant decrease of oxytetracycline concentration in meat slurry as a result of irradiation was noted. A dose of 1 kGy reduced concentration of tetracycline to ca 40% and a dose of 3 kGy reduced it to ca 3%. In ground poultry meat a dose of 1 kGy reduced this antibiotic concentration to 70%, a dose of 3 kGy reduced oxytetracycline concentration to 35% and a 5 kGy dose reduced it up to ca 18% of initial concentration. It can be concluded that irradiation of poultry meat with radurization doses can cause some difficulties in detection of tetracycline residues in meat using traditional microbiological methods of detection. (author).

Effect of irradiation on oxytetracycline residues in poultry meat

International Nuclear Information System (INIS)

Mazurowski, P.

1994-01-01

The purpose of the study was an evaluation of the effect of ionizing radiation on detection of oxytetracycline residues in poultry meat. Oxytetracycline was chosen as a representative of tetracyclines which are often applied in poultry for therapeutical reasons. The experiment was conducted using both broiler meat treated by oxytetracycline and slurry of broiler meat containing appropriate concentration of this antibiotic. A traditional microbiological method for determination of antibiotics antimicrobial activity was used. A significant decrease of oxytetracycline concentration in meat slurry as a result of irradiation was noted. A dose of 1 kGy reduced concentration of tetracycline to ca 40% and a dose of 3 kGy reduced it to ca 3%. In ground poultry meat a dose of 1 kGy reduced this antibiotic concentration to 70%, a dose of 3 kGy reduced oxytetracycline concentration to 35% and a 5 kGy dose reduced it up to ca 18% of initial concentration. It can be concluded that irradiation of poultry meat with radurization doses can cause some difficulties in detection of tetracycline residues in meat using traditional microbiological methods of detection. (author)

On the role of the residual stress state in product manufacturing

NARCIS (Netherlands)

Zijlstra, G.; Groen, M.; Post, J.; Ocelik, V.; de Hosson, J.Th.M.

2016-01-01

This paper concentrates on the effect of the residual stress state during product manufacturing of AISI 420 steel on the final shape of the product. The work includes Finite Element (FE) calculations of the distribution of the residual stresses after metal forming and a heat treatment. The evolution

Pesticide residues in birds and mammals

Science.gov (United States)

Stickel, L.F.; Edwards, C.A.

1973-01-01

exposure to an organochlorine pesticide, the concentrations of residues in the different tissues are ordinarily directly correlated with each other. When the dosage is at lethal levels, or when stored residues are mobilised to lethal levels, the balanced relationship is disrupted. The concentrations of residues in the brain provide the most rigorous criteria for diagnosis of death due to these chemicals, and levels are generally similar across a wide range of species of birds and mammals. Residues in liver are closely correlated with recent dose, either from direct intake or from mobilisation from storage, and so reflect hazardous exposure. Residues in the whole carcass show the storage reserve, and so indicate the potential for adverse effects from lethal mobilisation or from the continuous slow mobilisation that occurs during the normal processes of metabolism and excretion. A synchronous, rapid, and widespread decline in weight and thickness of shells of eggs laid by many species of wild birds occurred in the late 1940's and has persisted. Birds of prey were primarily affected; exceptions apparently are the result of lesser exposure because of different food habits. Many species of fish-eating birds are also affected. Others, however, appear to be more resistant and to accumulate much higher residues before shell-thinning occurs. Seed-eating birds do not appear to have been generally affected; their exposure is ordinarily lower, but physiological factors also seem to be involved. A relationship between shell-thinning and population decline has been established for many species. In exceptional cases, such as the herring gull, persistent re-nesting and other population reactions have overcome adverse effects at the population level. The discovery of shell-thinning among natural populations, and the hypothesis that this thinning was related to the occurrence of organochlorine pesticides, stimulated experimental studies to determine wheth

Further studies on the use of enzyme profiles to monitor residue accumulation in wildlife: Plasma enzymes in starlings fed graded concentrations of morsodren, DDE, Aroclor 1254, and malathion

Science.gov (United States)

Dieter, M.P.

1975-01-01

Wild-trapped starlings (Sturnus vulgaris) were fed concentrations of Morsodren (2, 4, and 8 ppm), DDE or Aroclor 1254 (5, 25, and 100 ppm), or malathion (8, 35, and 160 ppm) that were found to be sublethal in pen-reared Coturnix quail fed these amounts for 12 weeks. Plasma enzymes had to be measured earlier than planned in starlings fed Morsodren (at three weeks) or the organochlorine compounds (at seven weeks) because of unexpected, subsequent mortality. Variations in enzyme response were greater in wild than in pen-reared birds, but not enough to mask the toxicant-induced changes in enzyme activity. Cholinesterase activities decreased in birds fed Morsodren or malathion, and increased in those fed the organochlorine compounds. Lactate dehydrogenase activities increased two-fold in starlings fed Morsodren and two- to four-fold in those fed the organochlorine compounds, but only 50% in those fed malathion. Further examination of enzyme profiles showed that creatine kinase and aspartate aminotransferase activities increased two-to four-fold in birds fed Morsodren or the organochlorine compounds but not at all in those fed malathion. Thus the classes of environmental contaminants fed to starlings could be easily distinguished by these enzymatic parameters. Evaluation of enzymatic profiles appears to be a potentially valuable technique to monitor the presence of toxicants in wild populations, especially if used to complement standard chemical residue analyses. Here the residue analyses showed, after three weeks feeding, that mercury in the carcasses reflected the concentrations fed daily, whereas accumulation in the livers was two- to four-fold greater. After seven weeks feeding, liver residues of either organochlorine compound were about three-fold higher than the concentrations fed daily. However, four times as much DDE as Aroclor 1254 had accumulated in the carcasses.

Gamma exposure rate reduction and residual radium-226 concentrations resulting from decontamination activities conducted at the former uranium millsite in Shiprock, New Mexico

International Nuclear Information System (INIS)

Hans, J.M. Jr.; Hurst, T.L.

1981-01-01

Gamma radiation surveys and residual radium 226 soil samples were taken as part of the decontamination activities of the former Shiprock uranium mill site in New Mexico. In order to facilitate the decontamination activities, the mill site and its contaminated environs were divided into 6 major areas. Extensive data are presented in 2 appendices of the pre- and post-decontamination gamma ray exposure rates made on mill site, and of radium 226 concentrations in surface soil samples. A training program established on the mill site by the Navajo Engineering and Construction Authority is described

On-site treatment and landfilling of MSWI air pollution control residues

DEFF Research Database (Denmark)

Lundtorp, Kasper; Jensen, Dorthe Lærke; Sørensen, Mette Abildgaard

2003-01-01

the process, collected through the drainage system, contained large concentrations of salts (Cl: 14–30 g/l, Na: 4–9 g/l, K: 5–11 g/l, Ca: 2–12 g/l) but low concentrations of trace metals (e.g. Pb: 14–100 μg/l, Cd: leaching......Air pollution control (APC) residues from municipal solid waste incineration (MSWI) are difficult to landfill due to substantial leaching of trace metals. An on-site pretreatment prior to landfilling of APC-residues was investigated in terms of bench-scale experiments with a semidry APC...... of the leaching, concentrations of trace metals were reduced by up to four orders of magnitude....

Use of ultrasound in petroleum residue upgradation

Energy Technology Data Exchange (ETDEWEB)

Sawarkar, A.N.; Pandit, A.B.; Samant, S.D.; Joshi, J.B. [Mumbai Univ., Mumbai (India). Inst. of Chemical Technology

2009-06-15

The importance of bottom-of-the barrel upgrading has increased in the current petroleum refining scenario because of the progressively heavier nature of crude oil. Heavy residues contain large concentrations of metals such as vanadium and nickel which foul catalysts and reduce the potential effect of residue fluidized catalytic cracking. This study showed that the cavitational energy induced by ultrasound be be successfully used to upgrade hydrocarbon mixtures. Conventional processes for the upgrading of residual feedstocks, such as thermal cracking and catalytic cracking, were carried out in the temperature range of 400-520 degrees C. Experiments were performed on 2 vacuum residues, Arabian mix vacuum residue (AMVR) and Bombay high vacuum residue (BHVR) and 1 Haldia asphalt (HA). These were subjected to acoustic cavitation for different reaction times from 15 to 120 minutes at ambient temperature and pressure. Two acoustic cavitation devices were compared, namely the ultrasonic bath and ultrasonic horn. In particular, this study compared the ability of these 2 devices to upgrade the petroleum residues to lighter, more value-added products. Different surfactants were used to examine the effect of ultrasound on upgrading the residue when emulsified in water. In order to better understand the reaction mechanism, a kinetic model was developed based on the constituents of the residue. The ultrasonic horn was found to be more effective in bringing about the upgrading than ultrasonic bath. The study also showed that the acoustic cavitation of the aqueous emulsified hydrocarbon mixture could reduce the asphaltenes content to a greater extent than the acoustic cavitation of non-emulsified hydrocarbon mixture. 20 refs., 11 tabs., 17 figs.

Quadratic residues and non-residues selected topics

CERN Document Server

Wright, Steve

2016-01-01

This book offers an account of the classical theory of quadratic residues and non-residues with the goal of using that theory as a lens through which to view the development of some of the fundamental methods employed in modern elementary, algebraic, and analytic number theory. The first three chapters present some basic facts and the history of quadratic residues and non-residues and discuss various proofs of the Law of Quadratic Reciprosity in depth, with an emphasis on the six proofs that Gauss published. The remaining seven chapters explore some interesting applications of the Law of Quadratic Reciprocity, prove some results concerning the distribution and arithmetic structure of quadratic residues and non-residues, provide a detailed proof of Dirichlet’s Class-Number Formula, and discuss the question of whether quadratic residues are randomly distributed. The text is a valuable resource for graduate and advanced undergraduate students as well as for mathematicians interested in number theory.

Chemical modelling of pore water composition from PFBC residues

International Nuclear Information System (INIS)

Karlsson, L.G.

1991-01-01

The concentration of trace elements varies depending on the source of the coal and also due to the combustion process used. Mercury is one important element among the trace elements in the coal residues, generally recognised as potentially harmful to the biological system. To predict the pore water concentrations of mercury and other important constituents leached from coal combustion residues disposal sites, mechanistic data on chemical reactions are required. The present study is an application of a basially thermodynamical approach using the geochemical code EQ3NR. The presence of discrete solid phases that control the aqueous concentrations of major elements such as aluminium, calcium and silicon are identified. Solid phases are modelled in equilibrium with a hypothetical pore water at a pH range of 7-11. In this study the thermodynamic database of EQ3NR has been complemented with data for cadmium, mercury and lead taken from the OECD/NEA Thermodynamic Database and from a compilation made by Lindsay. Possible solubility limiting phases for the important trace elements arsenic, cadmium, chromium, copper, mercury, nickel and lead have been identified. Concentrations of these trace elements as a function of pH in the hypothetical pore water were calculated using mechanistic thermodynamial data. The thermodynamical approach in this study seems justified because most solid residues that are either present or expected to form during weathering have relatively fast precipitation/dissolution kinetics. (21 refs., 18 figs., 5 tabs.)

A combined process of adsorption and Fenton-like oxidation for furfural removal using zero-valent iron residue.

Science.gov (United States)

Li, Furong; Bao, Jianguo; Zhang, Tian C; Lei, Yutian

2015-01-01

In this study, the feasibility of using a combined adsorption and Fenton-like oxidation process (with zero-valent iron (ZVI) residue from heat wraps as an absorbent and catalyst) to remove furfural in the solution was evaluated. The influencing parameters (e.g. pH, H2O2 concentration, initial furfural concentration) and the reusability of ZVI residue (to replace the iron powder) were estimated. The ZVI residue was found to have much better adsorption effect on furfural at pH 2.0 compared with pH 6.7. For Fenton-like reaction alone with ZVI residue, the highest furfural removal of 97.5% was observed at the concentration of 0.176 mol/L H2O2, and all of the samples had >80% removal efficiency at different initial furfural concentrations of 2, 10, 20, 30 and 40 mmol/L. However, with a combined adsorption and Fenton-like oxidation, the removal efficiency of furfural was nearly 100% for all treatments. The ZVI residue used for furfural removal was much better than that of iron powder in the Fenton-like reaction at a seven-cycle experiment. This study suggests the combined process of adsorption and Fenton-like oxidation using ZVI residue is effective for the treatment of furfural in the liquid.

Treatment and processing of residues of fermentation; Behandlung und Verwertung von Gaerrueckstaenden

Energy Technology Data Exchange (ETDEWEB)

Doehler, H.; Schliebner, P. [Kuratorium fuer Technik und Bauwesen in der Landwirtschaft (KTBL), Darmstadt (Germany)

2007-07-01

With the transformation of the EEG (Renewable Energy Resources Act), the number of biogas plants increased rapidly. Additionally, an enlargement of the performance of the plants and a regional concentration process take place. Recently, processing routes for liquid manure will be considered in order to reduce problems of the surplus of nutrients as well as the costs of the transport of the water-rich residues of fermentation. Under this aspect, the authors of the contribution under consideration report on procedures for the processing of residues of fermentation as well as costs and utilization of these procedures. By the example of an agrarian society, four procedures for the output and processing of residues of fermentation are compared with one another regarding to expenditure of work time, investments and economy: Output of residues of fermentation, treatment of residues of fermentation by separation, processing of residues of fermentation by means of diaphragm technology, processing of residues of fermentation by means of evaporation technology. The processing routes reduce the residues of fermentation by 60 %. Thus, the costs of output and the necessary storage capacities for residues of fermentation are reduced. Presently, no savings regarding to work completion by the processing of the residues of fermentation can be obtained. The specific total costs of the investigated procedures are between 2.64 Euro/m{sup 3} according to the procedure with separation and to 8.64 Euro/m{sup 3} according to the diaphragm processing route. An enhanced demand of investment does not cause compellingly the highest specific total costs of the procedures. In comparison to the output of residues of fermentation, the examined procedures for the processing of residues of fermentation do not result in economical and ergonomic advantages. The high costs of investment and operating cost of the processing of residues of fermentation cannot be compensated by the reduced costs of output

Criteria for the restoration of mining residues in Germany

International Nuclear Information System (INIS)

Kraus, W.; Ettenhuber, E.; Gehrcke, K.; Przyborowski, S.

2000-01-01

Residues from uranium mines and mills and from the mining of silver, tin, cobalt, nickel and other ores, as well as of coal mineralized with uranium, are situated in densely populated regions of Germany. Social and political pressure required an urgent investigation and evaluation of these residues in order to identify relevant residues which could not be disregarded from the radiation protection point of view. There were two categories of residues. First, for huge former uranium mining and milling sites, the original owner could be made liable for restoration. A large Federal rehabilitation programme for the Wismut sites was started immediately after the political change in the former East Germany in 1990 and was based on radiological as well as on social and economic concerns. Secondly, for a large number of smaller residues, sometimes dating back to the middle ages, an evaluation of their radiological relevance was necessary before decisions could be taken on the justification of a restoration. This was the objective of a Federal programme on registration, investigation and evaluation of mining residues. Up to now only minor remedial activities have been carried out in cases where an urgent need had been detected. Criteria developed by the German Commission on radiological protection (SSK) were applied for the evaluation of the residues. The primary criterion for the justification of a restoration was an annual individual effective dose of 1 mSv for all exposure pathways except for the inhalation of radon. For inhalation of radon, the primary criterion for justification was a long term average outdoor radon concentration of 50 Bq/m 3 caused by the residues. Both levels were taken in addition to the natural background radiation level at a given site. These criteria were based on the upper end of the 'normal' range of naturally occurring exposure or concentration levels. SSK established reference levels in measurable quantities (activity concentration in soil

Radioactivity of combustion residues from coal-fired power stations

International Nuclear Information System (INIS)

Vom Berg, W.; Puch, K.H.

1996-01-01

Each year in Germany, about 18 mill. t of combustion residues are produced from the combustion of bituminous coal and lignite. They are utilized to a great extent in the construction industry and in mining. During the combustion of coal, the radio-nuclides remain predominantly in the ash. The radionuclide concentration in lignite ash is within the range of that in natural soil. The combustion residues of bituminous coal contain radio-nuclides of a similar order of magnitude as also can occur in natural rock. The utilization of combustion residues in construction materials makes a negligible contribution to radiation exposure through retention in buildings. (orig.) [de

Gewichtsverlies, serumnatriumconcentratie en restverschijnselen bij patiëntjes met hypertone dehydratie door onvoldoende borstvoeding [Weight loss, serum sodium concentration and residual symptoms in patients with hypernatremic dehydration caused by insufficient breastfeeding

NARCIS (Netherlands)

Breuning-Boers, J.M.; Dommelen, P. van; Wouwe, J.P. van; Verkerk, P.H.

2006-01-01

Objective. To determine the relationship between serum sodium concentration and weight loss as well as residual symptoms in newborns with hypernatremic dehydration caused by insufficient breastfeeding; and to determine the sensitivity of the following rule of thumb 'if weight loss is less than 10%,

The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

Science.gov (United States)

Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

2016-04-01

Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis.

Lindane residues in fish inhabiting Nigerian rivers

International Nuclear Information System (INIS)

Okereke, G.U.; Dje, Y.

1997-01-01

Analysis for residues of lindane in fish collected from various rivers close to rice agroecosystems showed that the concentrations of lindane ranged from none detectable to 3.4 mg kg -1 . Fish from rivers where strict regulations prohibits its use had no detectable lindane residues while appreciable amounts of lindane were found in fish were such restriction was not enforced with the variation attributed to the extent of use of lindane in the area of contamination. The investigation confirms that the use of lindane in rice production in Nigeria can cause the contamination of fish in nearby rivers. (author). 16 refs, 2 tab

Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.

Science.gov (United States)

Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

2007-06-01

A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production.

USAGE OF ALGAE SPECIES CHAETOMORPHA GRACILIS AND CH. AEREA FOR DEPURATION PROCESS OF THE RESIDUAL WATERS

Directory of Open Access Journals (Sweden)

SALARU VICTOR

2008-11-01

Full Text Available Rapid increase of the population on the globe scale imposes maximum exploration of the natural resources and first of all of the aquatic resources. As a result are obtained an enormous quantity of residual waters which pollute the waters from rivers, lakes, freatic and underground waters. Elaboration of the depuration methods for residual waters the quantity of which grows continuously, is one of the most up to dated issue of the world. The physical-chemical depuration methods of the residual waters are very expensive and lack the efficiency we would like to have. The most efficient method proved to be the biological method using some species of algae and superior aquatic plants. In our experiences we have involved filamentous green algae Chaetomorpha gracilis and Ch. aerea for depuration of the sewerage water from town Cimishlia. The concentration of the mineral nitrogen compounds in the residual water is around 92,5 mg/l, and of the phosphates 10,1 mg/l. There were used the following concentration of the sewerage water: 10%, 25% and 50%. The most intense development of algae Chaetomorpha aerea was observed in the variant with 10% of residual water, in which the total concentration of the nitrogen was 10,24 mg/l, and of the phosphates 1,05 mg/l. For this variant the depuration water level was about 56,9%. For the case with Chaetomorpha gracilis, the depuration level for the same concentration of the residual water constituted 55,9 %. Increase of the concentration of the polluted water inhibits development of the algae reducing to the minimum their capacity to assimilate the nitrogen and the phosphor. In the solutions with 50 % of residual waters, the algae didn't die, but at the same time they didn't develop. From this results that both algae may be used in the phytoamelioration of the residual waters being diluted at 10% with purified water.

Effects of organic additives on preferred plane and residual stress of copper electroplated on polyimide

International Nuclear Information System (INIS)

Kim, Jongsoo; Kim, Heesan

2010-01-01

Effects of the preferred plane and the residual stress of an electroplated copper on polyethylene glycol (PEG) and 3-N,N-dimethylaminodithiocarbamoyl-1-propanesulfonic acid (DPS) were studied. Polyimide film coated with sputtered copper was used as a substrate. Preferred plane, residual stress, and impurity level in the electroplated copper were measured by an X-ray diffractometry (XRD), calculated by Stoney's equation, and analyzed with secondary ion mass spectroscopy (SMS), respectively. With increasing the concentration of PEG, the preferred plane changed in the order (1 0 0) and (1 1 0) while with increasing the concentration of DPS, the preferred plane changed in the order (1 1 0), (1 0 0), and (1 1 1). Based on the modified preferred growth model, where the amount of additive adsorbed on a plane is newly assumed to be proportional to its surface energy in vacuum, the predicted preferred planes correspond to the experimental results. The residual stress of the electroplated copper depended on the type of additive as well as its concentration but was independent of the preferred plane. For example, PEG and DPS induced tensile and compressive residual stresses in the electroplated copper, respectively, and their magnitudes increased with their concentrations. The dependency of residual stress on the additives was explained by the incorporated additives into the electroplated copper.

Visceral organ weights, digestion and carcass characteristics of beef bulls differing in residual feed intake offered a high concentrate diet.

Science.gov (United States)

Fitzsimons, C; Kenny, D A; McGee, M

2014-06-01

This study examined the relationship of residual feed intake (RFI) with digestion, body composition, carcass traits and visceral organ weights in beef bulls offered a high concentrate diet. Individual dry matter (DM) intake (DMI) and growth were measured in a total of 67 Simmental bulls (mean initial BW 431 kg (s.d.=63.7)) over 3 years. Bulls were offered concentrates (860 g/kg rolled barley, 60 g/kg soya bean meal, 60 g/kg molasses and 20 g/kg minerals per vitamins) ad libitum plus 0.8 kg grass silage DM daily for 105 days pre-slaughter. Ultrasonic muscle and fat depth, body condition score (BCS), muscularity score, skeletal measurements, blood metabolites, rumen fermentation and total tract digestibility (indigestible marker) were determined. After slaughter, carcasses and perinephric and retroperitoneal fat were weighed, carcasses were graded for conformation and fat score and weight of non-carcass organs, liver, heart, kidneys, lungs, gall bladder, spleen, reticulo-rumen full and empty and intestines full, were determined. The residuals of the regression of DMI on average daily gain (ADG), mid-test metabolic BW (BW0.75) and the fixed effect of year, using all animals, were used to compute individual RFI coefficients. Animals were ranked on RFI and assigned to high (inefficient), medium or low groupings. Overall mean ADG and daily DMI were 1.6 kg (s.d.=0.36) and 9.4 kg (s.d.=1.16), respectively. High RFI bulls consumed 7 and 14% more DM than medium and low RFI bulls, respectively (P0.05) for ADG, BW, BCS, skeletal measurements, muscularity scores, ultrasonic measurements, carcass weight, perinephric and retroperitoneal fat weight, kill-out proportion and carcass conformation and fat score. However, regression analysis indicated that a 1 kg DM/day increase in RFI was associated with a decrease in kill-out proportion of 20 g/kg (Pcarcass conformation of 0.74 units (Pcarcass organs did not differ (P>0.05) between RFI groups except for the empty weight of reticulo

A Design of Portable Pesticide Residue Detection System Based on the Enzyme Electrode

Directory of Open Access Journals (Sweden)

Xia SUN

2013-03-01

Full Text Available In this paper, a portable detection system was designed based on amperometric acetylcholinesterase biosensor for rapidly detecting pesticide residues in fruits and vegetables. There were potentiostat, three electrode system, differential amplification circuit and double integral analog to digital (A/D circuit modules in this system. The measurement principle of this system was depended on the weak current from enzyme catalyzing substrate in acetylcholinesterase biosensor for detecting pesticide residues. The weak current generated by the enzyme biosensor was changed into 0-5 V standard voltage signal by this system as an output signal. The proposed system was investigated with eight kinds of standard pesticide of different concentrations, the results showed that the detection limits were all lower than 10 ng/kg. Thus, a new effective home-made system of detecting pesticide residues with portable, easy-to-use, fast response was developed. The pesticide residues rapid detection system can collect the weak current signal generated by electrochemical reaction and on-site detect the concentration of pesticide residues in real fruits and vegetables samples.

The effect of commercial processing procedures on 14C-carbendazim residues in soybean oil and tomato

International Nuclear Information System (INIS)

Peng Genyuan; Wang Huaguo; Qi Mengwen; Wang Fujun; Zhou Changjiu

1994-01-01

Under simulated agricultural practices, soybean plants were treated with 14 C-labelled carbendazim during the blooming stage. The residue in seeds was determined to be 0.067 ppm; corresponding to 0.076 ppm respectively. After subjecting the oil to degumming, alkali treatment, bleaching and deodorization, 53.7% of original radioactivity was removed. Deodorization was the most effect process, removing about 20% of the residue. The concentration of residues in the deodorized oil decreased about 30%. In soybean seed and cake, the residue was mainly present as carbendazim, the concentration of the other metabolites did not exceed 30% of the residue. Tomatoes grown on a field plot were treated with 14 C-carbendazim. After harvest, the tomatoes were processed into tomato juice and canned whole fruit. The magnitude and nature of residues in samples taken at several processing steps were determined to evaluate the effect of commercial processing on removing or eliminating the residues. The results showed that the surface residues on tomato would be removed efficiently by simple washing of tomato. A buffer solution of phosphate had the highest efficiency. Tomato juice contained lower residues than canned whole fruit

Analysis of residual toluene in food packaging via headspace extraction method using gas chromatography

International Nuclear Information System (INIS)

Lim, Ying Chin; Mohd Marsin Sanagi

2008-01-01

Polymeric materials are used in many food contact applications as packaging material. The presence of residual toluene in this food packaging material can migrate into food and thus affect the quality of food. In this study, a manual headspace analysis was successfully designed and developed. The determination of residual toluene was carried out with standard addition method and multiple headspace extraction, MHE) method using gas chromatography-flame ionization detector, GC-FID). Identification of toluene was performed by comparison of its retention time with standard toluene and GC-MS. It was found that the suitable heating temperature was 180 degree Celsius with an optimum heating time of 10 minutes. The study also found that the concentration of residual toluene in multicolored sample was higher compared to mono colored sample whereas residual toluene in sample analyzed using standard addition method was higher compared to MHE method. However, comparison with the results obtained from De Paris laboratory, France found that MHE method gave higher accuracy for sample with low analyte concentration. On the other hand, lower accuracy was obtained for sample with high concentration of residual toluene due to systematic errors. Comparison between determination methods showed that MHE method is more precise compared to standard addition method. (author)

Chemical modelling of trace elements in pore water from PFBC residues containing ammonia

International Nuclear Information System (INIS)

Karlsson, L.G.; Brandberg, F.

1993-01-01

Ammonia is added to the PFBC process with the purpose to reduce the emissions of NO x in the stack gases. The design of the system for cleaning the stack gases will lead to an increased adsorption of ammonia and an accumulation of soluble ammonium salts in the cyclone ash from PFBC processes. This can be an environmental problem since the amounts will increase over the coming years and there will be a need to dispose the residues. When infiltrating rainwater penetrates the disposed residues ammonia and ammonium salts result in a contamination of the pore water with ammonia in the disposed residues. This entail the solubility of several trace elements in the residues that form soluble complexes with ammonia will increase and cause an increased contamination of groundwater and surface water. In this study the increased solubilities is calculated for the trace elements cadmium, cobalt, copper, mercury, nickel, silver and zinc in the residues using thermodynamical data. The calculations have been performed with probable solid phases of the trace elements at oxidizing and reducing conditions as a function of pH and at varying concentration of ammonia in the pore water. The thermodynamic calculations have been performed with the geochemical code EQ3NR. The results from the calculations show that as a concentration of 17 mg NH 3 /l in the pore water of the residues increases the solubilities for copper and silver. If the concentration of ammonia increases to 170 mg NH 3 /l will the solubilities increase also for cadmium, nickel and zinc. (12 refs., 39 figs.)

Quantification of heavy metals from residual waste and ashes from the treatment plant of residual water Reciclagua and,effects for the health of those workers which manipulate those residuals

International Nuclear Information System (INIS)

Guerrero D, J.J.

2004-01-01

concentrations greater than 0.5% in weight, as long as the analysis of plasma emission spectroscopy very low concentrations are identified already that this method causes the destruction of the sample achieving the identification of all the present elements. With the obtained results we are able to compare the concentrations of the metals before and after the leaching and we calculate by this way the percentage of efficiency for each one of the variables that were managed in the development of the study, obtaining the extraction of those toxic, and valuable metals, present in the muds until of 100%. Based on the results we can mention that the workers are exposed to aerosols and powders of these toxic residuals which contain heavy metals. (Author)

Viscoelastic properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover

Science.gov (United States)

The rheological properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover were investigated. The corn stover MFC gels exhibited concentration-dependent viscoelastic properties. Higher corn stover MFC concentrations resulted in stronger viscoelastic properties. Th...

Effects of deltamethrin, dimethoate, and chlorpyrifos on survival and reproduction of the collembolan Folsomia candida and the predatory mite Hypoaspis aculeifer in two African and two European soils.

Science.gov (United States)

Jaabiri Kamoun, Ikram; Jegede, Olukayode O; Owojori, Olugbenga J; Bouzid, Jalel; Gargouri, Radhia; Römbke, Jörg

2018-01-01

Indiscriminate use of pesticides is rampant in most parts of Africa, but only scanty ecotoxicological data exist for the protection of soil organisms-and these data were usually obtained under temperate conditions, including the use of Organisation for Economic Co-operation and Development (OECD) standard test protocols. In order to assess the effects of 3 commonly used pesticides (deltamethrin, dimethoate, chlorpyrifos) on soil fauna in Africa, noncontaminated natural soils were collected from Nigeria and Tunisia. In addition, 2 common test soils, OECD artificial soil and European (Landwirtschaftliche Untersichungs- und Forschungsanstalt [LUFA]) 2.3 soil, were used in OECD standard reproduction tests. Two microarthropod species, the springtail Folsomia candida and the predatory mite Hypoaspis aculeifer, were exposed in these 4 soils spiked individually with the 3 insecticides. Results show that the collembolan F. candida was more sensitive than the mite H. aculeifer for all 3 insecticides. The toxicity of each insecticide in the 4 soils differed, with few exceptions, by less than an order of magnitude. However, the pattern of toxicity was not consistent, that is, the lowest toxicity was often but not always found in OECD artificial soil. Soil- and pesticide-specific patterns of toxicity to F. candida and H. aculeifer might be related to the physicochemical properties of the soils and thus the availability of the 3 pesticides. Following the rules laid down in the European Union for the registration of pesticides and using standard European exposure scenarios, neither an acute nor a chronic risk of dimethoate and chlorpyrifos can be excluded (with few exceptions) in all 4 soils. Lower risks were identified for deltamethrin. For pesticide used in Africa, an environmental risk assessment based on data gained in tests with at least 1 additional natural field soil, preferably of African origin, should be performed using the same risk assessment principles as in the

Effect of selected insecticides on SF9 insect cell line

International Nuclear Information System (INIS)

Saleh, M.; Rahmo, A.; Hajjar, J.

2013-01-01

The toxic effect of three insecticides: dimethoate (organophosphate insecticide), acetamiprid (neonicotinoid insecticide) and deltamethrin (pyrethroid insecticide) were evaluated in vitro on cultured Sf9 cell line. Cell growth inhibition was measured by the 3- (4,5- dimethylthiazol - 2-yl) - 2,5 - diphenyl tetrazolium bromide (MTT) assay. Regression Analysis was used to estimate the 20% inhibition of cells growth (IC 20). The IC 20 values obtained for deltamethrin, acetamipridand dimethoate were: 46.8, 61.6 and 68.9 μM, respectively. The proportion of phagocytic cells was positively correlated with the applied concentrations of the insecticides. (author)

Functional residual capacity measurement by heptafluoropropane in ventilated newborn lungs

OpenAIRE

Kusztrich, Ariane

2012-01-01

Objective: Heptafluoropropane is an inert gas commercially used as propellant for inhalers. Since heptafluoropropane can be detected in low concentrations, it could also be used as a tracer gas to measure functional residual capacity. The aim of the present study was to validate functional residual capacity measurements by heptafluoropropane wash-in/wash-out (0.8%) during mechanical ventilation in small, surfactant-depleted lungs using a newborn piglet model. Design: Prospective laborato...

Optimization of prehydrolysis time and substrate feeding to improve ethanol production by simultaneous saccharification and fermentation of furfural process residue.

Science.gov (United States)

He, Jianlong; Zhang, Wenbo; Liu, Xiaoyan; Xu, Ning; Xiong, Peng

2016-11-01

Ethanol is a very important industrial chemical. In order to improve ethanol productivity using Saccharomyces cerevisiae in fermentation from furfural process residue, we developed a process of simultaneous saccharification and fermentation (SSF) of furfural process residue, optimizing prehydrolysis cellulase loading concentration, prehydrolysis time, and substrate feeding strategy. The ethanol concentration obtained from the optimized process was 19.3 g/L, corresponding 76.5% ethanol yield, achieved by running SSF for 48 h from 10% furfural process residue with prehydrolysis at 50°C for 4 h and cellulase loading of 15 FPU/g furfural process residue. For higher ethanol concentrations, fed-batch fermentation was performed. The optimized fed-batch process increased the ethanol concentration to 37.6 g/L, 74.5% yield, obtained from 10% furfural process residue with two additions of 5% substrate at 12 and 24 h. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Residue levels and risk assessment of pesticides in nuts of China.

Science.gov (United States)

Liu, Yihua; Shen, Danyu; Li, Shiliang; Ni, Zhanglin; Ding, Ming; Ye, Caifen; Tang, Fubin

2016-02-01

The pesticide residue levels of three nuts (chestnut, walnut, pinenut) collected from seven main producing areas of China were investigated. Twenty-nine pesticides, including organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and two fungicides (triadimefon and buprofezin) were analyzed by gas chromatography (GC). Four OPs (acephate, dimethoate, chlorpyrifos and parathion-methyl) were found in 11.4% samples, with the concentrations of 19.0 µg kg(-1) to 74.0 µg kg(-1). Six OCs (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) were found in 18.2% samples, with the concentrations of 2.0 µg kg(-1) to 65.7 µg kg(-1). Among OCs, p,p-DDE and α-HCH were the dominant isomer for DDT and HCH. Five PYs (fenpropathrin, fenvalerate, cypermethrin, bifenthrin and cyhalothrin) were found in 15.9% samples, with the concentrations of 2.5 µg kg(-1) to 433.0 µg kg(-1). Fenpropathrin was the most frequently detected pesticide. In addition, triadimefon and buprofezin were detected only in two samples. For the tested nuts, 25.0% samples with multiple residues (containing more than two pesticides) were noted, even up to 9.1% samples with five pesticide residues. The residue of 15.9% samples was higher than the maximum residue limits (MRLs) of China. The short-term risks for the tested nuts were below 1.2%, and the highest long-term risk was 12.58%. The cumulative risk (cHI) for the tested pesticides were 8.43% (OPs), 0.42% (OCs), 12.82% (PYs) and 0.15% (fungicides), respectively. The total cHI was 21.82%. There was no significant health risk for consumers via nuts consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.

Forest residues in cattle feed

Directory of Open Access Journals (Sweden)

João Elzeário Castelo Branco Iapichini

2012-12-01

Full Text Available The ruminants are capable of converting low-quality food, when they are complementes with high-energy source. Through the use of regional agricultural residues is possible to conduct more economical production systems, since energetic foods have high cost in animal production. There is very abundant availability of residues in agroforestry activities worldwide, so that if a small fraction of them were used with appropriate technical criteria they could largely meet the needs of existing herds in the world and thus meet the demands of consumption of protein of animal origin. The Southwest Region of São Paulo State has large area occupied by reforestation and wide availability of non-timber forest residues, which may represent more concentrated energetic food for ruminant production. This experiment aimed to evaluate the acceptability of ground pine (20, 30 and 40%, replacing part of the energetic food (corn, present in the composition of the concentrate and was performed at the Experimental Station of Itapetininga - Forest Institute / SMA, in the dry season of 2011. It were used four crossbred steers, mean 18 months old, average body weight of 250 kg, housed in a paddock provided with water ad libitum and covered troughs for supplementation with the experimental diet. The adjustment period of the animals was of 07 days and the measurement of the levels of consumption, physiological changes, acceptability and physiological parameters were observed during the following 25 days. The concentrate supplement was formulated based on corn (76.2%, Soybean Meal (20%, urea (2%, Ammonium sulfate (0.4%, calcite (1.4%, Mineral Core (1% and finely ground Pine Cone, replacing corn. In preparing food, the formulas were prepared to make them isoproteic/energetic, containing the following nutrient levels: 22% Crude Protein (CP and 79% of Total Nutrients (TDN. The animals received the supplement in three steps for each level of cone replaced, being offered in the

Anopheles coluzzii larval habitat and insecticide resistance in the island area of Manoka, Cameroon.

Science.gov (United States)

Etang, Josiane; Mbida Mbida, Arthur; Ntonga Akono, Patrick; Binyang, Jerome; Eboumbou Moukoko, Carole Else; Lehman, Leopold Gustave; Awono-Ambene, Parfait; Talipouo, Abdou; Ekoko Eyisab, Wolfgang; Tagne, Darus; Tchoffo, Romeo; Manga, Lucien; Mimpfoundi, Remy

2016-05-20

The effectiveness of Long-Lasting Insecticidal Nets and Indoor Residual Spraying in malaria vector control is threatened by vector resistance to insecticides. Knowledge of mosquito habitats and patterns of insecticide resistance would facilitate the development of appropriate vector control strategies. Therefore, we investigated An. coluzzii larval habitats and resistance to insecticides in the Manoka rural island area compared with the Youpwe suburban inland area, in Douala VI and II districts respectively. Anopheline larvae and pupae were collected from open water bodies in December 2013 and April 2014 and reared until adult emergence. Two to four day old emerging females were morphologically identified as belonging to the An. gambiae complex and used for WHO susceptibility tests with 4 % DDT, 0.75 % permethrin, and 0.05 % deltamethrin, with or without piperonyl butoxide (PBO) synergist. Control and surviving specimens were identified down to the species using a PCR-RFLP method. Survivors were genotyped for kdr L1014 mutations using Hot Oligonucleotide Ligation Assay. In both study sites, ponds, residual puddles, boats, and drains were identified as the major An. gambiae s.l. larval habitats. A total of 1397 females, including 784 specimens from Manoka and 613 from Youpwe, were used for resistance testing. The two mosquito populations displayed resistance to DDT, permethrin and deltamethrin, with variable mortality rates from 1 % to 90 %. The knock-down times were also significantly increased (at least 2.8 fold). Pre-exposure of mosquitoes to PBO did not impact on their mortality to DDT, conversely the mortality rates to permethrin and deltamethrin were significantly increased (7.56 ≤ X(2) ≤ 48.63, df = 1, p habitats have been identified, larval source management strategies may be trialed in this area as complementary vector control interventions.

Persistence and bioaccumulation of oxyfluorfen residues in onion.

Science.gov (United States)

Sondhia, Shobha

2010-03-01

A field study was conducted to determine persistence and bioaccumulation of oxyflorfen residues in onion crop at two growth stages. Oxyfluorfen (23.5% EC) was sprayed at 250 and 500 g ai/ha on the crop (variety, N53). Mature onion and soil samples were collected at harvest. Green onion were collected at 55 days from each treated and control plot and analyzed for oxyfluorfen residues by a validated high-performance liquid chromatography method with an accepted recovery of 78-92% at the minimum detectable concentration of 0.003 microg g(-1). Analysis showed 0.015 and 0.005 microg g(-1) residues of oxyfluorfen at 250 g a.i. ha(-1) rate in green and mature onion samples, respectively; however, at 500 g a.i.ha(-1) rates, 0.025 and 0.011 microg g(-1) of oxyfluorfen residues were detected in green and mature onion samples, respectively. Soil samples collected at harvest showed 0.003 and 0.003 microg g(-1) of oxyfluorfen residues at the doses 250 and 500 g a.i. ha(-1), respectively. From the study, a pre-harvest interval of 118 days for onion crop after the herbicide application is suggested.

Co-sintering of treated APC-residues with bottom ash

DEFF Research Database (Denmark)

Jensen, Dorthe Lærke; Bergfeldt, Britta; Vehlow, Jürgen

2001-01-01

the influence of co-sintering of Ferrox products with bottom ashes on the quality of the residues and the effects on the combustion process. Only few elements showed higher concentrations in the bottom ashes of these co-combustion tests compared to reference tests. No significant effect on the leaching......Air pollution control residues stabilised by means of the Ferrox process can be sager disposed of due to lower contents of soluble salts and lesssoluble heavy metals stabilised in iron oxides. Co-combustion tests in the Karlsruhe test incinerator TAMARA were carried out in order to investigate...... behaviour of the bottom ashes could be found. During the co-combustion process an increase in SO2 concentrations in the raw gas and slightly lower temperatures in the fuel bed could be observed....

On-line measurement of residual monomer during polymerisation of acrylamide using ultrasonics

International Nuclear Information System (INIS)

Ponraju, D.; Sebastian, Letha; Viswanathan, S.; Natarajan, A.; Palanichamy, P.; Jayakumar, T.; Baldev Raj

1996-01-01

An ultrasonic technique for the estimation of residual acrylamide monomer during the polymerization of aqueous acrylamide solution has been investigated. Polyacrylamide gel medium serves as a sensitive medium for detection and dosimetry of fast and thermal neutrons. This technique is based on the fact that the velocity of ultrasonic wave increases with the increase in elasticity due to polymerization. The percentage of residual acrylamide monomer is estimated using ultraviolet spectrophotometric analysis. The ultrasonic velocity is correlated with the residual monomer concentration

Hydrogenation upgrading of heavy oil residues

Energy Technology Data Exchange (ETDEWEB)

Krichko, A.A.; Maloletnev, A.S.; Mazneva, O.A.; Galkina, N.I. [Fossil Fuel Inst., Moscow (Russian Federation). Hydrogenation and Gasification Dept.; Suvorov, U.P.; Khadjiev, S.N. [Inst. Oil and Chemical Synthesis, Moscow (Russian Federation). Hydrogenation of Heavy Residues Dept.

1997-12-31

At present time in the world there is no simple and effective technology at low pressure (<15-20 MPa) which could give the opportunity to use oil residues for distillate fractions production. In Russia a process for hydrogenation (up 6 MPa hydrogen pressure) of high boiling point (b.p. >520 C) oil products, including high S, V and Ni contents ones, into distillates, feedstock for catalytic cracking (b.p. 360-520 C) and metal concentrates. The main point of the new process is as follows: the water solution of catalytic additive, for which purpose water soluble metal salts of VI-VIII groups are used, is mixed with heavy oil residues, dispersed and then subjected to additional supercavitation in a special apparatus. (orig.)

The effect of commercial processing procedures on {sup 14}C-carbendazim residues in soybean oil and tomato

Energy Technology Data Exchange (ETDEWEB)

Genyuan, Peng; Huaguo, Wang; Mengwen, Qi; Fujun, Wang; Changjiu, Zhou [Laboratory for the Application of Nuclear Techniques, Beijing Agricultural University, Beijing (China)

1994-06-01

Under simulated agricultural practices, soybean plants were treated with {sup 14}C-labelled carbendazim during the blooming stage. The residue in seeds was determined to be 0.067 ppm; corresponding to 0.076 ppm respectively. After subjecting the oil to degumming, alkali treatment, bleaching and deodorization, 53.7% of original radioactivity was removed. Deodorization was the most effect process, removing about 20% of the residue. The concentration of residues in the deodorized oil decreased about 30%. In soybean seed and cake, the residue was mainly present as carbendazim, the concentration of the other metabolites did not exceed 30% of the residue. Tomatoes grown on a field plot were treated with {sup 14}C-carbendazim. After harvest, the tomatoes were processed into tomato juice and canned whole fruit. The magnitude and nature of residues in samples taken at several processing steps were determined to evaluate the effect of commercial processing on removing or eliminating the residues. The results showed that the surface residues on tomato would be removed efficiently by simple washing of tomato. A buffer solution of phosphate had the highest efficiency. Tomato juice contained lower residues than canned whole fruit.

Residue management at Rocky Flats

International Nuclear Information System (INIS)

Olencz, J.

1995-01-01

Past plutonium production and manufacturing operations conducted at the Rocky Flats Environmental Technology Site (RFETS) produced a variety of plutonium-contaminated by-product materials. Residues are a category of these materials and were categorized as open-quotes materials in-processclose quotes to be recovered due to their inherent plutonium concentrations. In 1989 all RFETS plutonium production and manufacturing operations were curtailed. This report describes the management of plutonium bearing liquid and solid wastes

Decolorization of textile industry wastewater in solid state fermentation with Peach-Palm (Bactris gasipaes residue

Directory of Open Access Journals (Sweden)

J. A. Chicatto

2018-02-01

Full Text Available Abstract In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF system. SSF assays were conducted with peach-palm (Bactris gasipaes residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.

Decolorization of textile industry wastewater in solid state fermentation with Peach-Palm (Bactris gasipaes) residue.

Science.gov (United States)

Chicatto, J A; Rainert, K T; Gonçalves, M J; Helm, C V; Altmajer-Vaz, D; Tavares, L B B

2018-02-15

In this work we have assessed the decolorization of textile effluents throughout their treatment in a solid-state fermentation (SSF) system. SSF assays were conducted with peach-palm (Bactris gasipaes) residue using the white rot fungus Ganoderma lucidum EF 31. The influence of the dye concentration and of the amounts of peach-palm residue and liquid phase on both the discoloration efficiency and enzyme production was studied. According to our results, independently of experimental conditions employed, laccase was the main ligninolytic enzyme produced by G. lucidum. The highest laccase activity was obtained at very low effluent concentrations, suggesting the existence of an inhibitory effect of higher concentrations on fungal metabolism. The highest percentage of color removal was reached when 10 grams of peach palm residue was moistened with 60 mL of the final effluent. In control tests carried out with the synthetic dye Remazol Brilliant Blue R (RBBR) decolorization efficiencies about 20% higher than that achieved with the industrial effluent were achieved. The adsorption of RBBR on peach-palm residue was also investigated. Equilibrium tests showed that the adsorption of this dye followed both Langmuir and Freundlich isotherms. Hence, our experimental results indicate that peach-palm residue is suitable substrate for both laccase production and color removal in industrial effluents.

Techno-economic evaluation of residue exhaustion in batch rectification ethanol production plant

Directory of Open Access Journals (Sweden)

Jaćimović Branislav M.

2017-01-01

Full Text Available This paper presents the techno-economic optimization of batch plant for production of rectified alcohol based on the concentration of ethanol in residue. The aim of the analysis was to determine the extent to which it is economically profitable to exhaust the residual liquid in boiler. The "profit production" criterion is used for calculations.

Stability of the anthocyanins extracted from residues of the wine industry

Directory of Open Access Journals (Sweden)

Edmar Clemente

2011-09-01

Full Text Available Anthocyanins are highly important due to their antioxidant capacity. They are the most important among the phenolic compounds and one of the main natural dyes used in the food industry. In this research, residue of processed grapes was used to investigate the presence of anthocyanins, the possibility of their extraction from the residue, and their stability. The extraction solution consisted of 70 mL of ethanol 70% and 30 mL of HCl 0.1% at pH 2.0. The results found for the processed grapes residue was 26.20 mg.100 g-1. In order to evaluate stability, caffeic acid was added at 0.5:1 w/v; 0.8:1 w/v; and 1:1 w/v concentrations. Anthocyanins extract reached the greatest stability at 0.5:1 w/v concentration, with 82.47% color retention and a half-life period of 15 days. Therefore, the use of this organic acid as a stabilizer for anthocyanins is feasible.

Ammonia volatilization from crop residues and frozen green manure crops

Science.gov (United States)

de Ruijter, F. J.; Huijsmans, J. F. M.; Rutgers, B.

2010-09-01

Agricultural systems can lose substantial amounts of nitrogen (N). To protect the environment, the European Union (EU) has adopted several directives that set goals to limit N losses. National Emission Ceilings (NEC) are prescribed in the NEC directive for nitrogen oxides and ammonia. Crop residues may contribute to ammonia volatilization, but sufficient information on their contribution to the national ammonia volatilization is lacking. Experiments were carried out with the aim to assess the ammonia volatilization of crop residues left on the soil surface or incorporated into the soil under the conditions met in practice in the Netherlands during late autumn and winter. Ammonia emission from residues of broccoli, leek, sugar beet, cut grass, fodder radish (fresh and frozen) and yellow mustard (frozen) was studied during two winter seasons using volatilization chambers. Residues were either placed on top of soil or mixed with soil. Mixing residues with soil gave insignificant ammonia volatilization, whereas volatilization was 5-16 percent of the N content of residues when placed on top of soil. Ammonia volatilization started after at least 4 days. Total ammonia volatilization was related to C/N-ratio and N concentration of the plant material. After 37 days, cumulative ammonia volatilization was negligible from plant material with N concentration below 2 percent, and was 10 percent of the N content of plant material with 4 percent N. These observations can be explained by decomposition of plant material by micro-organisms. After an initial built up of the microbial population, NH 4+ that is not needed for their own growth is released and can easily emit as NH 3 at the soil surface. The results of the experiments were used to estimate the contribution of crop residues to ammonia volatilization in the Netherlands. Crop residues of arable crops and residues of pasture topping may contribute more than 3 million kg NH 3-N to the national ammonia volatilization of the

Food toxicology. Residues and contaminants: Risks and consumer protection; Lebensmitteltoxikologie. Rueckstaende und Kontaminanten: Risiken und Verbraucherschutz

Energy Technology Data Exchange (ETDEWEB)

Nau, H. [Tieraerztliche Hochschule Hannover, ZA Lebensmitteltoxikologie (Germany); Steinberg, P. [Potsdam Univ., Inst. fuer Ernaehrungswissenschaft (Germany); Kietzmann, M. (eds.) [Tieraerztliche Hochschule Hannover, Inst. fuer Pharmakologie, Toxikologie/Pharmazie (Germany)

2003-07-01

In a detailed introduction, the basic methods of risk assessment for potentially toxic food constituents are presented as well as the analytical methods applied for measuring even very small concentrations of contaminants. The main classes of substances relevant in foods ar represented, i.e. animal drugs, fungicides and herbicides, natural toxins, contaminants, prions from BSE-infested animals and residues of 'new' proteins and 'new' DNA from genetically modified foods. New legislation in Germany and Europe is presented including the National Residue Monitoring Plant which is to enable annual monitoring of residue concentrations in foods derived from animals. (orig.)

Manual for implementing residual radioactivity guidelines

International Nuclear Information System (INIS)

Gilbert, T.L.; Eckerman, K.F.; Hansen, W.R.; Healy, J.W.; Kennedy, W.E.; Napier, B.A.; Solday, J.K.

1986-01-01

The US Department of Energy (DOE) has recently issued guidelines for residual radioactivity at Formerly Utilized Sites Remedial Action Program (FUSRAP) and remote Surplus Facilities Management Program (SFMP) sites. A manual for implementing these guidelines has been prepared jointly by four DOE laboratories (ANL, LANL, ORNL, and PNL) and is being issued as a supplement to the guidelines. The manual presents procedures and tables for deriving site-specific guidelines for levels of residual radionuclide concentrations in soil that must not be exceeded if a site is to be released for unrestricted use. Guidance for implementing DOE ALARA policy for remedial actions is also included. The concentration factor method is used in the pathway analysis for deriving soil guidelines. The analysis has been structured in a manner that explicitly identifies all of the factors involved. Tables are provided for dose-conversion factors and pathway factors from which environmental transport factors for each radionuclide and pathway may be calculated. The scenarios used for deriving the environmental transport factors and dose conversion factors, and the manner in which the information provided in the manual is used to derive site-specific soil guidelines will be presented

Evaluation of Crops Sensitivity to Atrazine Soil Residual

Directory of Open Access Journals (Sweden)

E Izadi

2012-02-01

Full Text Available Abstract In order to study the sensitivity of 9 crops to atrazine soil residual, two separate experiments were conducted in field and greenhouse conditions. First experiment was conducted in a field with treated soil by atrazine based on split plot and the results evaluated in greenhouse conditions. Treatments in the field experiment included two organic manure application rates (0 and 50 t/ha as main plots and 2 atrazine application rates (2 and 4 kg/ha atrazine a.i. as sob plots. After corn harvesting soil was sampled at 0-15 cm surface layer in each plots in 15 points, after mixing the samples. Wheat, barley, sugar beet, pea, lens and colza planted in pots at greenhouse. Second experiment conducted in greenhouse conditions for evaluation of atrazine soil residual in completely randomized design. Treatments included atrazine soil residual concentrations (0, 0.2, 0.5, 1, 5, 10 and 15 mg/kg soil and crops included wheat, barley, sugar beet, pea, lens, rape, bean and tomato. Results showed that atrazine residue had no effect on crops growth in field experiment treated with atrazine. It seems that atrazine residue in filed soil is lower that its damage threshold for crops or maybe for its fast removal in field than in control conditions. But in bioassay experiment (greenhouse experiment crops response to atrazine residues were different. Results showed that onion and pea were most susceptible ant tolerant crops between studied species and based of ED50 parameter the other crops tolerance to total residue ranked as: pea< bean< lentil< sugar beet< tomato< barley< wheat< rape< onion. Keywords: Atrazine residue, Pea, Bean, Lentil, Sugar beet, Barley, Wheat, Rape, Tomato

Thermal and long-term freezing stability of ivermectin residues in sheep milk

NARCIS (Netherlands)

Cerkvenik, V.; Doganoc, D.Z.; Skubic, V.; Beek, W.M.J.; Keukens, H.J.

2001-01-01

The stability of ivermectin residues in sheep milk under conditions of pasteurization (74 °C, 40 s), high pasteurization (80 °C, 1 min), and boiling (100 °C, 10 s) based on residue content (at a level of concentration of about 2 ?g/kg and 30 ?g/kg of H2B1a) and sort of ingestion (in vitro, in vivo)

Identification of TCT, a novel knockdown resistance allele mutation and analysis of resistance detection methods in the voltage-gated Na⁺ channel of Culex pipiens pallens from Shandong Province, China.

Science.gov (United States)

Liu, Hong-Mei; Cheng, Peng; Huang, Xiaodan; Dai, Yu-Hua; Wang, Hai-Fang; Liu, Li-Juan; Zhao, Yu-Qiang; Wang, Huai-Wei; Gong, Mao-Qing

2013-02-01

The present study aimed to investigate deltamethrin resistance in Culex pipiens pallens (C. pipiens pallens) mosquitoes and its correlation with knockdown resistance (kdr) mutations. In addition, mosquito‑resistance testing methods were analyzed. Using specific primers in polymerase chain reaction (PCR) and allele-specific (AS)-PCR, kdr gene sequences isolated from wild C. pipiens pallens mosquitoes were sequenced. Linear regression analysis was used to determine the correlation between the mutations and deltamethrin resistance. A kdr allelic gene was cloned and sequenced. Analysis of the DNA sequences revealed the presence of two point mutations at the L1014 residue in the IIS6 transmembrane segment of the voltage‑gated sodium channel (VGSC): L1014F, TTA→TTT, replacing a leucine (L) with a phenylalanine (F); L1014S, TTA→TCA, replacing leucine (L) with serine (S). Two alternative kdr-like mutations, L1014F and L1014S, were identified to be positively correlated with the deltamethrin-resistant phenotype. In addition a novel mutation, TCT, was identified in the VGSC of C. pipiens pallens. PCR and AS-PCR yielded consistent results with respect to mosquito resistance. However, the detection rate of PCR was higher than that of AS-PCR. Further studies are required to determine the specific resistance mechanism. PCR and AS-PCR demonstrated suitability for mosquito resistance field tests, however, the former method may be superior to the latter.

Sustainable System for Residual Hazards Management

International Nuclear Information System (INIS)

Kevin M. Kostelnik; James H. Clarke; Jerry L. Harbour

2004-01-01

Hazardous, radioactive and other toxic substances have routinely been generated and subsequently disposed of in the shallow subsurface throughout the world. Many of today's waste management techniques do not eliminate the problem, but rather only concentrate or contain the hazardous contaminants. Residual hazards result from the presence of hazardous and/or contaminated material that remains on-site following active operations or the completion of remedial actions. Residual hazards pose continued risk to humans and the environment and represent a significant and chronic problem that require continuous long-term management (i.e. >1000 years). To protect human health and safeguard the natural environment, a sustainable system is required for the proper management of residual hazards. A sustainable system for the management of residual hazards will require the integration of engineered, institutional and land-use controls to isolate residual contaminants and thus minimize the associated hazards. Engineered controls are physical modifications to the natural setting and ecosystem, including the site, facility, and/or the residual materials themselves, in order to reduce or eliminate the potential for exposure to contaminants of concern (COCs). Institutional controls are processes, instruments, and mechanisms designed to influence human behavior and activity. System failure can involve hazardous material escaping from the confinement because of system degradation (i.e., chronic or acute degradation) or by external intrusion of the biosphere into the contaminated material because of the loss of institutional control. An ongoing analysis of contemporary and historic sites suggests that the significance of the loss of institutional controls is a critical pathway because decisions made during the operations/remedial action phase, as well as decisions made throughout the residual hazards management period, are key to the long-term success of the prescribed system. In fact

The effect of delignification process with alkaline peroxide on lactic acid production from furfural residues

Directory of Open Access Journals (Sweden)

Yong Tang

2012-11-01

Full Text Available Furfural residues produced from the furfural industry were investigated as a substrate for lactic acid production by simultaneous saccharification and fermentation (SSF. Alkaline peroxide was used for delignification of furfural residues to improve the final lactic acid concentration. The residue was treated with 1.3% to 1.7% hydrogen peroxide at 80 °C for 1 h with a substrate concentration of 3.33%. SSF of furfural residues with different delignification degrees were carried out to evaluate the effect of delignification degree on lactic acid production. Using corn hydrolysates/ furfural residues as substrates, SSF with different media were carried out to investigate the effect of lignin on the interaction between enzymes and lactic acid bacteria. Lactic acid bacteria had a negative effect on cellulase, thus resulting in the reduction of enzyme activity. Lignin and nutrients slowed down the decreasing trend of enzyme activity. A higher delignification resulted in a slower fermentation rate and lower yield due to degradation products of lignin and the effect of lignin on the interaction between enzymes and lactic acid bacteria. For the purpose of lactic acid production, a moderate delignification (furfural residues with the lignin content of 14.8% was optimum.

Analysis of residual chlorine in simple drinking water distribution system with intermittent water supply

Science.gov (United States)

Goyal, Roopali V.; Patel, H. M.

2015-09-01

Knowledge of residual chlorine concentration at various locations in drinking water distribution system is essential final check to the quality of water supplied to the consumers. This paper presents a methodology to find out the residual chlorine concentration at various locations in simple branch network by integrating the hydraulic and water quality model using first-order chlorine decay equation with booster chlorination nodes for intermittent water supply. The explicit equations are developed to compute the residual chlorine in network with a long distribution pipe line at critical nodes. These equations are applicable to Indian conditions where intermittent water supply is the most common system of water supply. It is observed that in intermittent water supply, the residual chlorine at farthest node is sensitive to water supply hours and travelling time of chlorine. Thus, the travelling time of chlorine can be considered to justify the requirement of booster chlorination for intermittent water supply.

MICROBIOLOGICAL EVALUATION OF ANTIBIOTIC RESIDUES IN MEAT, MILK AND EGGS

Directory of Open Access Journals (Sweden)

Abdul Jabbar

2013-04-01

Full Text Available Microbiological tests are widely used to detect antibiotic residues in the meat, milk and eggs for better care of the quality and health safety. In the present study microbiological inhibition test i.e. Swab Test on Animal Food (STAF was developed indigenously for screening of animal foods for presence of antibiotic residues. In this test local isolated culture of Bacillus subtilis was used as a test microorganism due to its high sensitivity to detect a wide range of antibiotics commonly used in animal disorders. The concentration of spore suspension of Bacillus subtilis JS2004 used in the formation of STAF plate was optimized at 2x107 spores/ ml. At this concentration, inhibition zone around Neomycin control disc was 10-16 mm. Nutrient agar was used as a medium in spore suspension and 0.4% dextrose was added as a constituent of medium. Zones of inhibition around swab samples and Neomycin control disc were observed and the diameter was measured. All swab samples showing a minimum of 2 mm wide inhibition zone around them were considered as positive for presence of antibiotic residues. The swab samples showing no zone of inhibition or a zone measuring less than 2 mm were considered as negative. Results of application of STAF test was on animal food samples revealed the high incidence of antibiotic residues.

DDT residues in sediments from the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Sarkar, A.; SenGupta, R.

in the sediments from the Bay of Bengal. Peterson grab and hydrographic winch was used to collect the sediment samples. Each sample was extracted and cleaned. Residues were detected by electron capture gas chromatography. A range variation in the concentration...

Effect of Refining Processes on Magnitude and Nature of Malathion and Carbofuran Residues in Cotton Seed Oil

International Nuclear Information System (INIS)

Zayed, S.M.A.D.; Farghaly, M.; Mahdy, F.

2005-01-01

Cotton seeds obtained from 14 C-carbofuran or 14 C-malathion-treated plants contained 0.25% and 0.11% of the originally applied radioactivity, respectively. The concentration of malathion residues in oil, methanol soluble and in the seed cake amounted to 0.94, 2.6 and 1.7 ppm, respectively. Commercial processing procedures led to a gradual decrease in the total amount of 14 C-residues in oils with aged residues as well as in oil fortified with the radiolabelled insecticides. The refined oil contained only about 20% of the 14 C-residues originally present. The major residue in processed oil contained malathion, malathion monocarboxylic acid and alpha-(O,O-dimethyl phosphorodithio)-propionic acid. The concentration of 14 C-carbofuran residues in cotton seed oil, methanol extract and cake was 1.7, 12.3 and 2.4 ppm, respectively. The main residues in the oil were carbofuran and its phenol. The methanol solubles contained conjugated metabolites, which upon hydrolysis gave 3-hydroxy-carbofuran as a major product. Refinement reduced the residue in oil to 0.26 ppm. The residue in refined oil contained carbofuran and carbofuran phenol as main constituents together with smaller amounts of 3-hydroxy- and 3-keto carbofuran

Residual stresses

International Nuclear Information System (INIS)

Sahotra, I.M.

2006-01-01

The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

Accounting for Genotype-by-Environment Interactions and Residual Genetic Variation in Genomic Selection for Water-Soluble Carbohydrate Concentration in Wheat.

Science.gov (United States)

Ovenden, Ben; Milgate, Andrew; Wade, Len J; Rebetzke, Greg J; Holland, James B

2018-05-31

Abiotic stress tolerance traits are often complex and recalcitrant targets for conventional breeding improvement in many crop species. This study evaluated the potential of genomic selection to predict water-soluble carbohydrate concentration (WSCC), an important drought tolerance trait, in wheat under field conditions. A panel of 358 varieties and breeding lines constrained for maturity was evaluated under rainfed and irrigated treatments across two locations and two years. Whole-genome marker profiles and factor analytic mixed models were used to generate genomic estimated breeding values (GEBVs) for specific environments and environment groups. Additive genetic variance was smaller than residual genetic variance for WSCC, such that genotypic values were dominated by residual genetic effects rather than additive breeding values. As a result, GEBVs were not accurate predictors of genotypic values of the extant lines, but GEBVs should be reliable selection criteria to choose parents for intermating to produce new populations. The accuracy of GEBVs for untested lines was sufficient to increase predicted genetic gain from genomic selection per unit time compared to phenotypic selection if the breeding cycle is reduced by half by the use of GEBVs in off-season generations. Further, genomic prediction accuracy depended on having phenotypic data from environments with strong correlations with target production environments to build prediction models. By combining high-density marker genotypes, stress-managed field evaluations, and mixed models that model simultaneously covariances among genotypes and covariances of complex trait performance between pairs of environments, we were able to train models with good accuracy to facilitate genetic gain from genomic selection. Copyright © 2018 Ovenden et al.

Effect of handling and processing on pesticide residues in food- a review.

Science.gov (United States)

Bajwa, Usha; Sandhu, Kulwant Singh

2014-02-01

Pesticides are one of the major inputs used for increasing agricultural productivity of crops. The pesticide residues, left to variable extent in the food materials after harvesting, are beyond the control of consumer and have deleterious effect on human health. The presence of pesticide residues is a major bottleneck in the international trade of food commodities. The localization of pesticides in foods varies with the nature of pesticide molecule, type and portion of food material and environmental factors. The food crops treated with pesticides invariably contain unpredictable amount of these chemicals, therefore, it becomes imperative to find out some alternatives for decontamination of foods. The washing with water or soaking in solutions of salt and some chemicals e.g. chlorine, chlorine dioxide, hydrogen peroxide, ozone, acetic acid, hydroxy peracetic acid, iprodione and detergents are reported to be highly effective in reducing the level of pesticides. Preparatory steps like peeling, trimming etc. remove the residues from outer portions. Various thermal processing treatments like pasteurization, blanching, boiling, cooking, steaming, canning, scrambling etc. have been found valuable in degradation of various pesticides depending upon the type of pesticide and length of treatment. Preservation techniques like drying or dehydration and concentration increase the pesticide content many folds due to concentration effect. Many other techniques like refining, fermentation and curing have been reported to affect the pesticide level in foods to varied extent. Milling, baking, wine making, malting and brewing resulted in lowering of pesticide residue level in the end products. Post harvest treatments and cold storage have also been found effective. Many of the decontamination techniques bring down the concentration of pesticides below MRL. However, the diminution effect depends upon the initial concentration at the time of harvest, substrate/food and type of

Petroleum hydrocarbon residues in the marine environment of Bassein-Mumbai

International Nuclear Information System (INIS)

Chouksey, M.K.; Kadam, A.N.; Zingde, M.D.

2005-01-01

The paper reports PHc contamination in water, sediment and biota of the coastal area of Bassein-Mumbai in relation to relatively less polluted sites (Dabhol and Ratnagiri) off the west coast of India. To facilitate inter-comparison three standards have been used though the results are reported in terms of SAM (Residue of Saudi Arabian Mix crude). The concentration of PHc in water off Bassein-Mumbai varies widely (2.9-39.2 μg l -1 ) as compared to the average baseline (2.8 μgl -1 ) with higher values generally confined to creeks and estuaries. The higher concentration of PHc in the bottom water of shallow areas is attributed to the contribution from the sediment-associated petroleum residue. High concentration of PHc in the surficial sediment of inshore area Ratnagiri (107.7 ppm, dry wt) is perhaps the remnants of an oil spill that occurred in the Bombay High region on May 17, 1993. The majority of values of PHc concentration in the surficial sediment of the Bassein-Mumbai region exceed 15 ppm (dry wt) against the expected background ( -1 respectively is estimated for cores U11 and U12. Substantial increase in the concentration of PHc in sediment after 1950 in cores T8 and T10 correlates well with the establishment of refineries on the western shore of the Thane Creek in 1955-1960. A minor peak in most cores in the top 10 cm sediment probably results from biological transfer of PHc lower into the sediment by benthic organisms. Excess of PHc retained in the sediment of the Bassein-Mumbai region over the biogenic background is estimated at 40,000 t. The PHc residues (1.8-10.8 ppm, wet wt) in fish caught off Bassein-Mumbai do not suggest bioaccumulation. (author)

Levels of organochlorine pesticide residue in grasscutter (Thryonomys swinderianus) tissues

International Nuclear Information System (INIS)

Blankson-Arthur, S.

2009-06-01

Organochlorine pesticide residues have been determined in the muscle, liver and kidney tissues from a total of 45 grasscutter (Thryonomys swinderianus) meat samples obtained from the Gomoa district, a vegetable farming area in the Central Region of Ghana. All samples were analyzed for their residue content of the following organochlorine pesticides; DDT, DDE, hexachlorocyclohexane isomers, lindane (γ-HCH) and δ-HCH, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, alpha endosulfan, endosulfan sulfate, chlordane, heptachlor and methoxychlor. The results indicated that all the analyzed samples were contaminated with the studied organochlorine pesticides. Aldrin and heptachlor were the principal contaminants in all the samples. The muscle had the highest pollutant load. All organochlorine pesticides investigated were detected in the muscle tissues of the grasscutter at the following mean concentrations; aldrin 1.833μg /kg, heptachlor 0.695μg /kg, γ-HCH 0.283μg /kg, δ-HCH 0.108μg /kg, dieldrin 0.040 μg /kg, p,p'-DDT 0.019μg /kg. p,p'-DDE 0.014μg /kg, endrin 0.018μg /kg, endrin aldehyde 0.090μg /kg, endrin ketone 0.340μg /kg, α-endosulfan 0.162μg /kg, endosulfan sulfate 0.183μg /kg, gamma-chlordane 0.174μg /kg and methoxychlor 0.101μg /kg wet weight. The organochlorine pesticide residues were detected in the liver tissues at the following mean concentrations; aldrin 1.315μg /kg, heptachlor 0.530μg /kg, dieldrin 0.050μg /kg, γ-HCH 0.233μg /kg, δ-HCH 0.070μg /kg, p,p'-DDT 0.123μg /kg. p,p'-DDE 0.043μg /kg endrin aldehyde 0.110μg /kg, endrin ketone 0.115μg /kg, gamma-chlordane 0.093μg /kg and methoxychlor 0.128μg /kg wet weight. No endrin was however detected in the liver. The highest concentrations of γ-HCH, δ-HCH, endrin ketone and endrin aldehyde were measured in the kidney. The mean concentrations of γ-HCH and δ-HCH in the kidney were 0.435μg /kg and 0.107μg /kg respectively. Endrin aldehyde was detected at 0.135μg /kg in

Exposure of the Public from Large Deposits of Mineral Residues

International Nuclear Information System (INIS)

2011-06-01

All minerals and raw materials contain radionuclides of natural origin. In most situations, the exposure of humans to such radionuclides is considered to be part of the normal natural radiation background and is not generally of concern. In some cases, however, the radionuclide concentrations are elevated above normal levels or become elevated as a result of mineral processing activities, and measures for protecting against exposure to the material involved may need to be considered. The mineral or raw material is then treated as radioactive material for the purposes of radiation protection and falls within the definition of naturally occurring radioactive material (NORM). The IAEA has developed criteria for determining which materials need to be considered for regulatory control. For materials containing only radionuclides of natural origin, the criteria are an activity concentration of 1 Bq/g for 238 U, 235 U, 232 Th and their decay progeny and an activity concentration of 10 Bq/g for 40 K. These values were determined on the basis of the activity concentrations of these radionuclides in normal rocks and soil, and represent the (rounded) upper bounds of the ranges of such concentrations as determined by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The values are intended to apply to all solid materials except foodstuffs, material in transport and radioactive residues in the environment (for which separate criteria apply) and 40 K in the body (which is excluded entirely from regulatory requirements). While the radiation dose was not a consideration in the determination of the above-mentioned regulatory criteria, the IAEA has noted that doses received by individuals as a consequence of the use of these criteria are unlikely to exceed about 1 mSv in a year, excluding the emanation of radon. However, in the case of bulk volumes of material contaminating water pathways, such as large deposits of NORM residues from mining and

[Effects of rice cleaning and cooking process on the residues of flutolanil, fenobucarb, silafluofen and buprofezin in rice].

Science.gov (United States)

Satoh, Motoaki; Sakaguchi, Masayuki; Kobata, Masakazu; Sakaguchi, Yoko; Tanizawa, Haruna; Miura, Yuri; Sasano, Ryoichi; Nakanishi, Yutaka

2003-02-01

We studied the effect of cleaning and cooking on the residues of flutolanil, fenobucarb, silafluofen and buprofezin in rice. The rice had been sprayed in a paddy field in Wakayama city, with 3 kinds of pesticide application protocols: spraying once at the usual concentration of pesticides, repeated spraying (3 times) with the usual concentration of pesticides and spraying once with 3 times the usual concentration of pesticides. The residue levels of pesticide decreased during the rice cleaning process. Silafluofen, which has a higher log Pow value, remained in the hull of the rice. Fenobucarb, which has a lower log Pow value, penetrated inside the rice. The residue concentration of pesticide in polished rice was higher than that in pre-washed rice processed ready for cooking. During the cooking procedure, the reduction of pesticides in polished rice was higher than that in brown rice.

Pesticide residues in grapes, wine, and their processing products.

Science.gov (United States)

Cabras, P; Angioni, A

2000-04-01

In this review the results obtained in the 1990s from research on the behavior of pesticide residues on grapes, from treatment to harvest, and their fate in drying, wine-making, and alcoholic beverage processing are reported. The fungicide residues on grapes (cyproconazole, hexaconazole, kresoxim-methyl, myclobutanil, penconazole, tetraconazole, and triadimenol), the application rates of which were of a few tens of grams per hectare, were very low after treatment and were not detectable at harvest. Pyrimethanil residues were constant up to harvest, whereas fluazinam, cyprodinil, mepanipyrim, azoxystrobin, and fludioxonil showed different disappearance rates (t(1/2) = 4.3, 12, 12.8, 15.2, and 24 days, respectively). The decay rate of the organophosphorus insecticides was very fast with t(1/2) ranging between 0.97 and 3.84 days. The drying process determined a fruit concentration of 4 times. Despite this, the residue levels of benalaxyl, phosalone, metalaxyl, and procymidone on sun-dried grapes equalled those on the fresh grape, whereas they were higher for iprodione (1.6 times) and lower for vinclozolin and dimethoate (one-third and one-fifth, respectively). In the oven-drying process, benalaxyl, metalaxyl, and vinclozolin showed the same residue value in the fresh and dried fruit, whereas iprodione and procymidone resides were lower in raisins than in the fresh fruit. The wine-making process begins with the pressing of grapes. From this moment onward, because the pesticide on the grape surface comes into contact with the must, it is in a biphasic system, made up of a liquid phase (the must) and a solid phase (cake and lees), and will be apportioned between the two phases. The new fungicides have shown no effect on alcoholic or malolactic fermentation. In some cases the presence of pesticides has also stimulated the yeasts, especially Kloeckera apiculata, to produce more alcohol. After fermentation, pesticide residues in wine were always smaller than those on the

Irradiation of residual muds and its use in the oat cultivation

International Nuclear Information System (INIS)

Moreno, A.J.; Colin, C.A.; Gomeztagle, M.M.; Frias, P.H.

1997-01-01

The irradiation of residual muds samples from a wastewater treatment plant at gamma radiation dose of 15 kGy removes from muds on average: fats and oils (33%), detergent (92%), phenols (50%) and over 99% of microorganisms of total account. The evaluation of irradiated residual mud and without irradiation as soil conditioner in oat growing (avena safira), was realized by triplicate, using different rates (80, 60, 40 and 20%) of frank sandy soil and irradiated and non-irradiated residual mud. The growing with rates 60/40 % of soil and irradiated mud respectively, resulted being more adequate as soil conditioner. It is important to clarify that for putting residual mud it is necessary that metals concentration not exceed the maximum permissible levels for the soil type and the corresponding growing. (Author)

Optimization of ethanol production from garcinia cambogia residues and the effects of its medicinal component on production yield

International Nuclear Information System (INIS)

Ma, H.; Zhang, F.

2017-01-01

Garcinia cambogia, a Chinese herbal medicine, was popular due to its effect for weight loss. The main medical component inside was determined to be hydroxycitric acid (HCA). To realize the resource technology of garcinia cambogia residue, Optimum ethanol production from residues was investigated, and the effects of remaining HCA on the ethanol yield were investigated. A Plackett-Burman experimental design was used to screen the significance of several influencing factors, and cellulase, yeast extract, and KH2PO4 were observed to exert important effects. The optimum ethanol fermentation conditions were determined through an orthogonal design to include a cellulase concentration of 100 U/g, a yeast extract concentration of 15 g/L, and a KH2PO4 concentration of 1.0 g/L. The ethanol concentration obtained under optimal conditions was 4.0 g/L. The remained HCA in the residues showed minimal influences on ethanol fermentation and could even increase ethanol yield at low concentrations. (author)

Metallic elements fractionation in municipal solid waste incineration residues

Science.gov (United States)

Kowalski, Piotr R.; Kasina, Monika; Michalik, Marek

2016-04-01

Municipal solid waste incineration (MSWI) residues are represented by three main materials: bottom ash, fly ash and air pollution control (APC) residues. Among them ˜80 wt% is bottom ash. All of that materials are products of high temperature (>1000° C) treatment of waste. Incineration process allows to obtain significant reduction of waste mass (up to 70%) and volume (up to 90%) what is commonly used in waste management to reduce the amount need to be landfilled or managed in other way. Incineration promote accumulation non-combustible fraction of waste, which part are metallic elements. That type of concentration is object of concerns about the incineration residues impact on the environment and also gives the possibility of attempts to recover them. Metallic elements are not equally distributed among the materials. Several factors influence the process: melting points, volatility and place and forms of metallic occurrence in the incinerated waste. To investigate metallic elements distribution in MSWI residues samples from one of the biggest MSW incineration plant in Poland were collected in 2015. Chemical analysis with emphasis on the metallic elements content were performed using inductively coupled plasma optical emission (ICP-OES) and mass spectrometry (ICP-MS). The bottom ash was a SiO2-CaO-Al2O3-Fe2O3-Na2O rich material, whereas fly ash and APC residues were mostly composed of CaO and SiO2. All of the materials were rich in amorphous phase occurring together with various, mostly silicate crystalline phases. In a mass of bottom ash 11 wt% were metallic elements but also in ashes 8.5 wt% (fly ash) and ˜4.5 wt% (APC residues) of them were present. Among the metallic elements equal distribution between bottom and fly ash was observed for Al (˜3.85 wt%), Mn (770 ppm) and Ni (˜65 ppm). In bottom ash Fe (5.5 wt%), Cr (590 ppm) and Cu (1250 ppm) were concentrated. These values in comparison to fly ash were 5-fold higher for Fe, 3-fold for Cu and 1.5-fold for

Review on the Influences of Bagging Treatment on Pesticide Residue in Fruits

OpenAIRE

ZHAO Xiao-yun; XIE De-fang

2018-01-01

At present, bagging technology has been widely applicated in fruit cultivation. Impact of bagging treatment on the pesticide residues have different results. On the basis of existing achievements, this paper systematically analyzed the influence of different bagging treatments on pesticide residues:such as different ways of applying pesticide, pesticide concentration, number of applying pesticide; bagging materials, bagged layer; the type of pesticide(systemic pesticide, nonendoscopic pestici...

40 CFR 161.240 - Residue chemistry data requirements.

Science.gov (United States)

2010-07-01

.../feed (5), (14) [CR] [CR] [CR] [CR] EP EP 171-4 Meat/milk/poultry/eggs (6), (14) [CR] [CR] [CR] [CR... food/feed are required when detectable residues could concentrate on processing and thus require establishment of a food additive tolerance. (6) Livestock feeding studies are required whenever a pesticide...

Residual stresses

International Nuclear Information System (INIS)

Macherauch, E.

1978-01-01

Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

Anaerobic digestion of microalgae residues resulting from the biodiesel production process

International Nuclear Information System (INIS)

Ehimen, E.A.; Sun, Z.F.; Carrington, C.G.; Birch, E.J.; Eaton-Rye, J.J.

2011-01-01

The recovery of methane from post transesterified microalgae residues has the potential to improve the renewability of the 'microalgae biomass to biodiesel' conversion process as well as reduce its cost and environmental impact. This paper deals with the anaerobic digestion of microalgae biomass residues (post transesterification) using semi-continuously fed reactors. The influence of substrate loading concentrations and hydraulic retention times on the specific methane yield of the anaerobically digested microalgae residues was investigated. The co-digestion of the microalgae residues with glycerol as well as the influence of temperature was also examined. It was found that the hydraulic retention period was the most significant variable affecting methane production from the residues, with periods (>5 days) corresponding to higher energy recovery. The methane yield was also improved by a reduction in the substrate loading rates, with an optimum substrate carbon to nitrogen ratio of 12.44 seen to be required for the digestion process.

Compared cycling in a soil-plant system of pea and barley residue nitrogen

DEFF Research Database (Denmark)

Jensen, E.S.

1996-01-01

Field experiments were carried out on a temperate soil to determine the decline rate, the stabilization in soil organic matter and the plant uptake of N from N-15-labelled crop residues. The fate of N from field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) residues was followed...... mineralization of N was highly correlated to the concentrations of soluble C and N and the lignin:N ratio of residues. The contribution of residue-derived N to the inorganic N pool was at its maximum 30 DAI (10-55%) and declined to on average 5% after 3 years of decomposition. Residual organic labelled N...... in the top 10 cm soil declined rapidly during the initial 86 DAI for all residue types. Leaching of soluble organic materials may have contributed to this decline. At 216 DAI 72, 59 and 45% of the barley, mature pea and green pea residue N, respectively, were present in organic N-forms in the topsoil. During...

Insecticide resistance of Anopheles sinensis and An. vagus in Hainan Island, a malaria-endemic area of China.

Science.gov (United States)

Qin, Qian; Li, Yiji; Zhong, Daibin; Zhou, Ning; Chang, Xuelian; Li, Chunyuan; Cui, Liwang; Yan, Guiyun; Chen, Xiao-Guang

2014-03-03

Malaria is one of the most important public health problems in Southeast Asia, including Hainan Island, China. Vector control is the main malaria control measure, and insecticide resistance is a major concern for the effectiveness of chemical insecticide control programs. The objective of this study is to determine the resistance status of the main malaria vector species to pyrethroids and other insecticides recommended by the World Health Organization (WHO) for indoor residual sprays. The larvae and pupae of Anopheles mosquitoes were sampled from multiple sites in Hainan Island, and five sites yielded sufficient mosquitoes for insecticide susceptibility bioassays. Bioassays of female adult mosquitoes three days after emergence were conducted in the two most abundant species, Anopheles sinensis and An. vagus, using three insecticides (0.05% deltamethrin, 4% DDT, and 5% malathion) and following the WHO standard tube assay procedure. P450 monooxygenase, glutathione S-transferase and carboxylesterase activities were measured. Mutations at the knockdown resistance (kdr) gene and the ace-1 gene were detected by DNA sequencing and PCR-RFLP analysis, respectively. An. sinensis and An. vagus were the predominant Anopheles mosquito species. An. sinensis was found to be resistant to DDT and deltamethrin. An. vagus was susceptible to deltamethrin but resistant to DDT and malathion. Low kdr mutation (L1014F) frequency (P450 monooxygenase and carboxylesterase activities were detected in deltamethrin-resistant An. sinensis, and significantly higher P450 monooxygenase, glutathione S-transferase and carboxylesterase activities were found in malathion-resistant An. vagus mosquitoes. Multiple insecticide resistance was found in An. sinensis and An. vagus in Hainan Island, a malaria-endemic area of China. Cost-effective integrated vector control programs that go beyond synthetic insecticides are urgently needed.

Tocopherol isomer pattern in serum and stool of human following consumption of black currant seed press residue administered in whole grain bread.

Science.gov (United States)

Helbig, Dorit; Wagner, Andreas; Schubert, Rainer; Jahreis, Gerhard

2009-12-01

Serum gamma-tocopherol is thought to be associated with human health. The dietary influence of tocopherol and fibre-rich black currant seed press residue on serum and stool tocopherol concentration was investigated in a controlled human intervention study. Thirty-six women consumed bread enriched with black currant press residue (4 weeks). The resultant faecal and serum tocopherol concentrations were compared with those after a period consuming control bread without press residue and a normal baseline diet. Fibre intake and excretion, antioxidant capacity (TEAC), and vitamin C concentrations in serum and urine were also determined. Samples were obtained with a 5-day standardised diet at the end of each period. The press residue bread lead to significantly increased beta-, gamma-, delta- and total tocopherol intake, serum alpha-, beta-, gamma- and total tocopherol concentration (with and without lipid adjustment), fibre intake and urinary vitamin C concentration compared to control bread (Pconsumption could be due to a presumed interruption of the enzymatic tocopherol degradation mechanism by bread constituents.

Mineral analysis, anthocyanins and phenolic compounds in wine residues flour

Directory of Open Access Journals (Sweden)

Bennemann Gabriela Datsch

2016-01-01

Full Text Available This study analyzed the mineral content (N, P, K, S, Ca, Fe, Mg, Mn, Fe and Zn, anthocyanins and phenolic compounds in flours produced from residues of different grape cultivars from the wineries in the Southern region of Brazil. Mineral analysis showed a significant difference for all grape cultivar, with the exception for phosphorus content. Residues from cv. Seibel showed higher levels of N, Cu and Mg. The cultivars Ancelotta, Tanat and Bordô present higher contents of K, Zn, Mn, Fe and Ca. For the concentration of anthocyanins, cultivars Cabernet Sauvignon (114.7 mg / 100g, Tannat (88.5 mg / 100 g and Ancelotta (33.8 mg/100 g had the highest concentrations. The cultivars Pinot Noir (7.0 g AGE / 100 g, Tannat (4.3 g AGE / 100 g, and Ancelotta (3.9 g AGE / 100 g had the highest content of phenolic compounds. Considering these results, it became evident the potential of using the residue of winemaking to produce flour for human consumption, highlighting the grapes ‘Tannat' and ‘Ancellotta'.

Evaluation of residue-residue contact predictions in CASP9

KAUST Repository

Monastyrskyy, Bohdan

2011-01-01

This work presents the results of the assessment of the intramolecular residue-residue contact predictions submitted to CASP9. The methodology for the assessment does not differ from that used in previous CASPs, with two basic evaluation measures being the precision in recognizing contacts and the difference between the distribution of distances in the subset of predicted contact pairs versus all pairs of residues in the structure. The emphasis is placed on the prediction of long-range contacts (i.e., contacts between residues separated by at least 24 residues along sequence) in target proteins that cannot be easily modeled by homology. Although there is considerable activity in the field, the current analysis reports no discernable progress since CASP8.

Optimizing Biomass Feedstock Logistics for Forest Residue Processing and Transportation on a Tree-Shaped Road Network

Directory of Open Access Journals (Sweden)

Hee Han

2018-03-01

Full Text Available An important task in forest residue recovery operations is to select the most cost-efficient feedstock logistics system for a given distribution of residue piles, road access, and available machinery. Notable considerations include inaccessibility of treatment units to large chip vans and frequent, long-distance mobilization of forestry equipment required to process dispersed residues. In this study, we present optimized biomass feedstock logistics on a tree-shaped road network that take into account the following options: (1 grinding residues at the site of treatment and forwarding ground residues either directly to bioenergy facility or to a concentration yard where they are transshipped to large chip vans, (2 forwarding residues to a concentration yard where they are stored and ground directly into chip vans, and (3 forwarding residues to a nearby grinder location and forwarding the ground materials. A mixed-integer programming model coupled with a network algorithm was developed to solve the problem. The model was applied to recovery operations on a study site in Colorado, USA, and the optimal solution reduced the cost of logistics up to 11% compared to the conventional system. This is an important result because this cost reduction propagates downstream through the biomass supply chain, reducing production costs for bioenergy and bioproducts.

Design of a compressed air modulator to be used in comprehensive multidimensional gas chromatography and its application in the determination of pesticide residues in grapes.

Science.gov (United States)

Pizzutti, Ionara R; Vreuls, René J J; de Kok, André; Roehrs, Rafael; Martel, Samile; Friggi, Caroline A; Zanella, Renato

2009-04-10

In this study, a new modulator that is simple, robust and presents low operation costs, was developed. This modulator uses compressed air to cool two small portions in the first centimeters of the second chromatographic column of a comprehensive multidimensional gas chromatography (GCxGC) system. The results show a variation in the peak area less than 3 and 5% to alkanes and pesticides, respectively. The standard deviations for the retention times in the first and second dimension are around 0.05 min and 0.05s for all the compounds. The system was optimized with n-alkanes. The GCxGC system proposed was applied in the determination of pyrethroid pesticides (bifenthrin, cypermethrin, deltamethrin, fenvalerate, esfenvalerate, cis- and trans-permethrin) in grape samples. Samples were extracted by the mini-Luke modified method and pesticides were quantified by comprehensive multidimensional gas chromatography with micro electron-capture detection (microECD). The values of method limit of quantification (LOQ) were 0.01-0.02 mg kg(-1) for all studied pyrethroid and the values of recovery were between 94.3 and 115.2%, with good precision (RSDcompressed air has the potential for application in the analysis of a wider range of pesticide residues in other commodities since it provides low values of LOQ with acceptable accuracy and precision.

Evaluación de la b-cipermetrina para el control de Triatoma infestans Evaluation of beta-cypermethrin for control of Triatoma infestans

Directory of Open Access Journals (Sweden)

Eduardo Nicolás Zerba

1997-02-01

�-cypermethrin is more effective against the nymphs and that deltamethrin is more effective against the adults. Evaluation of the 50% lethal concentration (LC50 of the flowable formulations of both insecticides, placed on different surfaces, showed that their effectiveness on glass is similar, while on a ceramic surface deltamethrin is slightly more effective. The flowable formulations of the two insecticides were tested in 100 infested homes in the province of Santiago del Estero, Argentina. Deltamethrin was applied at a surface concentration of 25 mg/m² and ß-cypermethrin at 50 mg/m². The real surface concentrations of these products were analyzed from filter paper samples placed on walls and ceilings. Gas chromatography revealed good agreement with the target concentrations. In addition, entomological assessments were carried out 60, 90, 180, and 365 days after the treatments. Infestations were found only during the last assessment: in the peridomiciliary area of 10% of the houses treated with ß-cypermethrin and in 7% of the houses treated with deltamethrin (6% in the peridomiciliary area and 1% inside the house. The results indicate that ß-cypermethrin's effectiveness in controlling T. infestans when applied at a concentration of 50 mg/m² is similar to that of deltamethrin applied at a concentration of 25 mg/m².

Simultaneous determination of nitrite and nitrate residues in meat products marketed in Shiraz by high performance liquid chromatography

Directory of Open Access Journals (Sweden)

H Golkari

2012-08-01

Full Text Available Nitrite and nitrate are the key ingredients and play a multifunctional role in meat curing technology. Despite all of their desirable effects, the addition of nitrite to meat is the major cause of carcinogenic N-nitrosamines formation. In this study, the amount of residual nitrite and nitrate in meat products containing 61% to 80% meat were assessed. The samples were obtained at the fourth day of their production from Shiraz retails and analyzed using high performance liquid chromatography (HPLC. According to the results, the mean concentrations of residual nitrite and nitrate were estimated at 36.96 ± 7.38 and 85.81 ± 5.5 mg/kg in small-diameter (1.5-2 cm sausages. Meanwhile, in large-diameter (5.5-8 cm sausages the residues were estimated at 20.97 ± 3.28 and 124.85±5.3 mg/kg, respectively. In all analyzed samples, the residual nitrite level was found below the permitted level of 120 mg/kg which indicated the application of allowed concentrations of nitrite in such products. The mean values of residual nitrite and nitrate concentrations were statistically different (p

Treatment of the press residues of pressed grapes on an industrial scale

Energy Technology Data Exchange (ETDEWEB)

1978-04-24

EtOH and tartaric acid are recovered from press residues of grapes by distillation and concentration of the EtOH and extraction of the dried residue after removal of seeds with a mixture of H/sub 2/O and mineral acid. Vegetable oil is extracted from the seeds. Collidal substances are coagulated by roasting prior to extraction of tartaric acid. The grape skins are recovered in flake form.

Studies on distribution and residue of sulfur in simulated acid rain in vegetable and soil by using 35S

International Nuclear Information System (INIS)

Wan Zhaoliang; Liu Dayong

1995-01-01

Distribution and residue of sulfur in simulated acid rain in two kinds of vegetables (lettuce and Chinese cabbage) and three types of soils (acid yellow earth, acid and neutral purple soils) were studied by using 35 S tracer method. The results showed that the higher concentration of acid rain was sprayed, the more residue of sulfur in vegetable there would be. The residue of sulfur in vegetable varied with the different physical and chemical properties of soils, the order of sulfur residue in vegetable was: acid purple soil>acid yellow earth>neutral purple soil. In the same soil, the residue of sulfur in lettuce was higher than that in Chinese cabbage, for the same vegetable, the residue of sulfur in leaves were higher than that in stems. The order of sulfur residue in different soils was acid purple soil>acid yellow earth>neutral purple soil. The higher concentration of acid rain was sprayed, the more residue of sulfur in soil surface there would be. The sulfur residue varied with the depth of soil and the pH value of acid rain. With the increase of soil depth, a slight increase of sulfur residue with rain of ph 6 and a slight decrease with rain of pH 4.0 and 2.5 were found

Erythromycin residue in honey from the Southern Marmara region of Turkey.

Science.gov (United States)

Gunes, Nazmiye; Cibik, Recep; Gunes, Mesut Ertan; Aydin, Levent

2008-11-01

Honey samples, collected from the Southern Marmara region of Turkey, were analysed for erythromycin residues by liquid chromatography-mass spectrometry using electrospray ionization in the positive ion mode (LC-ESI-MS). Fifty samples, comprising chestnut, pine, linden and multi-flower honeys, were collected directly from hives and analyzed. The limit of detection and quantification were 6 and 20 ng g(-1), respectively, and recovery ranged from 85 to 89%. Four of the honey samples (8%) were found to be contaminated with erythromycin residues at concentrations ranging from 50 to 1776 ng g(-1). An erythromycin-fortified cake feeding assay was also performed in a defined hive to test the transfer of erythromycin residue to the honey matrix. In this test hive, the residue level in the honey, 3 months after dosing, was approximately 28 ng g(-1).

Chemical activation of gasification carbon residue for phosphate removal

Science.gov (United States)

Kilpimaa, Sari; Runtti, Hanna; Lassi, Ulla; Kuokkanen, Toivo

2012-05-01

Recycling of waste materials provides an economical and environmentally significant method to reduce the amount of waste. Bioash formed in the gasification process possesses a notable amount of unburned carbon and therefore it can be called a carbon residue. After chemical activation carbon residue could be use to replace activated carbon for example in wastewater purification processes. The effect of chemical activation process variables such as chemical agents and contact time in the chemical activation process were investigated. This study also explored the effectiveness of the chemically activated carbon residue for the removal of phosphate from an aqueous solution. The experimental adsorption study was performed in a batch reactor and the influence of adsorption time, initial phosphate concentration and pH was studied. Due to the carbon residue's low cost and high adsorption capacity, this type of waste has the potential to be utilised for the cost-effective removal of phosphate from wastewaters. Potential adsorbents could be prepared from these carbonaceous by-products and used as an adsorbent for phosphate removal.

Effects of storage and processing on residue levels of chlorpyrifos in soybeans.

Science.gov (United States)

Zhao, Liuwei; Ge, Jing; Liu, Fengmao; Jiang, Naiwen

2014-05-01

The residue levels of chlorpyrifos in soybeans during storage and processing were investigated. Soybeans were treated with chlorpyrifos aqueous solution and placed in a sealed plastic container. The residue of chlorpyrifos was determined in soybeans at six time points within 0 and 112days during storage and oil processing of the soybeans was conducted. The analysis of the residues of chlorpyrifos was carried out by gas chromatography-mass spectrometry (GC-MS). Results show that the dissipation of chlorpyrifos in soybeans is about 62% during the storage period. Moreover, the carryover of the residues from soybeans into oil is found to be related to the processing methods. Processing factor, which is defined as the ratio of chlorpyrifos residue concentration in oil sample to that in the soybean samples, was 11 and 0.25 after cold and hot pressing, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cover crops and crop residue management under no-till systems improve soils and environmental quality

Science.gov (United States)

Kumar, Sandeep; Wegner, Brianna; Vahyala, Ibrahim; Osborne, Shannon; Schumacher, Thomas; Lehman, Michael

2015-04-01

Crop residue harvest is a common practice in the Midwestern USA for the ethanol production. However, excessive removal of crop residues from the soil surface contributes to the degradation of important soil quality indicators such as soil organic carbon (SOC). Addition of a cover crop may help to mitigate these negative effects. The present study was set up to assess the impacts of corn (Zea mays L.) residue removal and cover crops on various soil quality indicators and surface greenhouse gas (GHG) fluxes. The study was being conducted on plots located at the North Central Agricultural Research Laboratory (NCARL) in Brookings, South Dakota, USA. Three plots of a corn and soybean (Glycine max (L.) Merr.) rotation under a no-till (NT) system are being monitored for soils and surface gas fluxes. Each plot has three residue removal (high residue removal, HRR; medium residue removal, MRR; and low residue removal, LRR) treatments and two cover crops (cover crops and no cover crops) treatments. Both corn and soybean are represented every year. Gas flux measurements were taken weekly using a closed static chamber method. Data show that residue removal significantly impacted soil quality indicators while more time was needed for an affect from cover crop treatments to be noticed. The LRR treatment resulted in higher SOC concentrations, increased aggregate stability, and increased microbial activity. The LRR treatment also increased soil organic matter (SOM) and particulate organic matter (POM) concentrations. Cover crops used in HRR (high corn residue removal) improved SOC (27 g kg-1) by 6% compared to that without cover crops (25.4 g kg-1). Cover crops significantly impacted POM concentration directly after the residue removal treatments were applied in 2012. CO2 fluxes were observed to increase as temperature increased, while N2O fluxes increased as soil moisture increased. CH4 fluxes were responsive to both increases in temperature and moisture. On average, soils under

Adulticidal Susceptibility Evaluation of Aedes albopictus Using New Diagnostic Doses in Penang Island, Malaysia.

Science.gov (United States)

Rahim, Junaid; Ahmad, Abu H; Ahmad, Hamdan; Ishak, Intan H; Rus, Adanan Che; Maimusa, Hamisu A

2017-09-01

Insecticide-based vector control approaches are facing challenges due to the development of resistance in vector mosquitoes. Therefore, a proper resistance surveillance program using baseline lethal concentrations is crucial for resistance management strategies. Currently, the World Health Organization's (WHO) diagnostic doses established for Aedes aegypti and Anopheles species are being used to study the resistance status of Aedes albopictus. In this study, we established the diagnostic doses for permethrin, deltamethrin, and malathion using a known susceptible reference strain. Five field-collected populations were screened against these doses, following the WHO protocol. This study established the diagnostic dose of malathion at 2.4%, permethrin at 0.95%, and deltamethrin at 0.28%, which differ from the WHO doses for Aedes aegypti and Anopheles spp. Among the insecticides tested on the 5 wild populations, only deltamethrin showed high effectiveness. Different susceptibility and resistance patterns were observed with permethrin, malathion, and dichloro-diphenyl-trichloroethane (DDT) at 4%. This study may assist the health authorities to improve future chemical-based vector control operations in dengue-endemic areas.

Analysis and measurement of residual stress distribution of vanadium/ceramics joints for fusion reactor applications

International Nuclear Information System (INIS)

Nemoto, Y.; Ueda, K.

1998-01-01

Vanadium alloys are considered as candidate structural materials for fusion reactor system. When vanadium alloys are used in fusion reactor system, joining with ceramics for insulating is one of material issues to be solved to make component of fusion reactor. In the application of ceramics/metal jointing and coating, residual stress caused by difference of thermal expansion rate between ceramics and metals is an important factor in obtaining good bonding strength and soundness of coating. In this work, residual stress distribution in direct diffusion bonded vanadium/alumina joint (jointing temperature: 1400 C) was measured by small area X-ray diffraction method. And the comparison of finite element method (FEM) analysis and actual stress distribution was carried out. Tensile stress concentration at the edge of the boundary of the joint in alumina was observed. The residual stress concentration may cause cracks in alumina, or failure of bonding. Actually, cracks in alumina caused by thermal stress after bonding at 1500 C was observed. The stress concentration of the joint must be reduced to obtain good bonded joint. Lower bonding temperature or to devise the shape of the outer surface of the joint will reduce the stress concentration. (orig.)

Identification of chemical signatures of gunshot residues in different fabrics

International Nuclear Information System (INIS)

Freitas, Joao Carlos Dias de

2010-01-01

The modern forensic science goes hand in hand with scientific research. The forensic scientists are faced every day with many cases requiring the analysis of residues from firing gun (gunshot residues). This works describes the development of a methodology to determine chemical signatures of shots from a firearm, by measuring the concentrations of Pb, Ba e Sb in the residues from these shots deposited near the entrance hole of bullets, based on the technique with high resolution inductively coupled plasma mass spectrometry (HRICP-MS). Shots were performed on five types of target-fabrics and collected testimonies from regions close to the entrance hole of projectiles. The results showed that the method enabled us to identify and distinguish the residues of the .38 caliber revolver and pistols .40 and 9mm caliber. The use of ternary graphs as a tool for data analysis helped to identify specific patterns of distribution of blank samples and gunshot residues deposited after firing revolvers and pistols. The methodology enabled the assignment of the origin of the shot through the confirmation of the residues collected also from the hands of shooters. As a result the methodology in police procedures and aims to add a valuable contribution to forensic investigations. (author)

Risk assessment for children exposed to DDT residues in various milk types from the Greek market.

Science.gov (United States)

Tsakiris, Ioannis N; Goumenou, Marina; Tzatzarakis, Manolis N; Alegakis, Athanasios K; Tsitsimpikou, Christina; Ozcagli, Eren; Vynias, Dionysios; Tsatsakis, Aristidis M

2015-01-01

The occurrence of residues of DDT and its metabolites was monitored in 196 cow milk samples of various pasteurized commercial types collected from the Greek market. Residue levels were determined by GC-MS analysis. In 97.4% of the samples at least one DDT isomer or one of the DDT metabolites was detected, in levels not exceeding the maximum permitted residue level by the EU. Hazard Index for both carcinogenic and non-carcinogenic effects was estimated under two assumptions: a) using DDT concentrations from positive samples and b) imputing LOD/2 as an arbitrary concentration for negative samples. No statistically significant differences in detected or summed residue (p > 0.05) concentrations between different milk types were observed, with the exception of specific metabolites of DDT in some milk types. Exposure assessment scenarios were developed for children aged 1, 3, 5, 7 and 12 years old based on estimated body weights and daily milk consumption. Hazard Indices for non-carcinogenic effects were below 0.109 covering also carcinogenic effects according to WHO approach. The cancer risk values for carcinogenic effects according to the US EPA Cancer Benchmark Concentration approach, ranged from 0.4 to 18. For both effects the highest values were calculated for the 1- to 3-year-old age groups. Copyright © 2014 Elsevier Ltd. All rights reserved.

Detection of chloramphenicol residue in bovine meat using Liquid Chromatography Mass Spectrometry

Directory of Open Access Journals (Sweden)

Widiastuti R

2014-03-01

Full Text Available Chloramphenicol (CAP is a broad spectrum antibiotic that has been banned in many countries due to its serius side effect to human. Detection of CAP residue in food has been determined to a minimum required performance limit (MRPL of 0.3 ng/g. The purpose of this research was to conduct the analysis of CAP residue in bovine meat by using LCMS and to study the presence of CAP residue in marketed bovine meat samples. LC separation was done on a Shimpack column C18 with ammonium acetate 10 mM/water as mobile phase, and ESI-MS analysis in negative ion mode. The coefficient of determination, R2 = 0.9981 at concentration of 0.125, 0.25, 0.63, 1,00 and 2.00 ng/g. Recovery at three fortification levels (0.25, 0.50 and 1.00 ng/g was in the range 77.5, 97.3 and 83.4%. The decision limit and the detection capability were 0.15 ng/g and 0.17 ng/g respectively. Analysis results of 52 marketed samples showed that CAP residue were detected in 9 samples in the concentration range of 0.14 to 2.70 ng/g and 6 among those positive samples were above the MRPL value. Therefore, it is important to increase the awareness and also to monitor regularly CAP residues in food originated from animal to provide safe food for the consumers.

Characterization of roadway stormwater system residuals for reuse and disposal options

International Nuclear Information System (INIS)

Jang, Yong-Chul; Jain, Pradeep; Tolaymat, Thabet; Dubey, Brajesh; Singh, Shrawan; Townsend, Timothy

2010-01-01

The chemical characterization of sediments accumulated in catch basins and stormwater ponds provides important information for assessing risks associated with management of these residuals upon removal of accumulated deposits in stormwater systems. In this study, over a period of 15 months, more than 150 residual samples were collected from 77 catch basin units and 22 stormwater ponds from 16 municipalities throughout the state of Florida. Concentrations (mg/kg) of metals and metalloids (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and zinc) and trace organics (volatile organics, semi-volatile organics, herbicides, and pesticides) in the sediments were measured. In addition, the synthetic precipitation leaching procedure (SPLP) was utilized to evaluate pollutant leachability risk for a subset of the samples collected. Measured pollutant concentrations were compared to corresponding risk-based guidelines in Florida (i.e., Florida soil cleanup target levels) to assess potential human health risks of beneficial use of these residuals through land application. Leached concentrations were compared to risk-based water quality guidelines (i.e., Florida groundwater cleanup target levels) to examine the potential for groundwater contamination. Although several metals (arsenic, barium, chromium, copper, nickel, lead, and zinc) were routinely detected in the catch basin and stormwater pond sediments, their concentrations were generally lower than the Florida's risk-based cleanup target levels for soils. A small number of organochlorine compounds (e.g., 4,4'-DDE, 4,4'-DDT) were detected, but only in a limited number of the samples (less than 10%); leaching of trace organic pollutants above the Florida risk-based groundwater thresholds was rare. The results suggest that when land-applied or beneficially used, these residuals are not expected to pose a significant threat to human health or the environment and the results of this research

Mercury concentrations in cattle from NW Spain.

Science.gov (United States)

López Alonso, M; Benedito, J L; Miranda, M; Castillo, C; Hernández, J; Shore, R F

2003-01-20

Mercury is a toxic metal that is released into the environment as a result of various industrial and agricultural processes. It can be accumulated by domestic animals and so contaminate human foodstuffs. To date, there is no information on mercury residues in livestock in Spain and the aim of the present study was to quantify the concentrations of mercury in cattle in two of the major regions in north-west Spain, Galicia (a largely rural region) and Asturias, which is characterised by heavy industry and mining. Total mercury concentrations were determined in tissue (liver, kidney and muscle) and blood from 284 calves (6-10 months old) and 56 cows (2-16 years old) from across the whole of the two regions. Mercury was usually detected in the kidney (62.4-87.5% of samples) but most (79.5-96%) liver, muscle and blood samples did not contain detectable residues. Renal mercury concentrations did not differ between male and female calves but were significantly greater in female calves than in cows. Unexpectedly, kidney mercury concentrations were significantly higher in calves from the predominantly rural region of Galicia (geometric mean: 12.2 microg/kg w.wt.) than in animals from the industrialised-mining region of Asturias (3.40 microg/kg w.wt.). Overall, mercury residues in cattle from NW Spain were similar to those reported in cattle from non-polluted areas in other countries and do not constitute a risk to animal or human health. Copyright 2002 Elsevier Science B.V.

Investigation of Sensitivity of Some Pulses and Agronomic Crops to Soil Residue of Idosulfuron-mesosulfurun Herbicide

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E. Izadi-Darbandi

2013-03-01

Full Text Available To study the sensitivity of chick pea, bean, lentil, rapeseed, sugarbeet and tomato to soil residual concentration of Idosulfuron-mesosulfurun herbicide, an experiment was carried out under controlled conditions at the College of Agriculture, Ferdowsi University of Mashhad, Iran, in 2010. The studied factors were the 6 mentioned crops, and 7 levels of soil residual concentration of Idosulfuron-mesosulfurun herbicide (0, 0.0015, 0.0037, 0.0079, 0.015, 0.031 and 0.047 mg per kg of soil. The factorial experiment was carried out as a completely randomized design with three replications. Crops' emergence percentage was determined one week after their emergence. Plants' survival percentage and shoot and root biomass production were measured 30 days after their emergence. Results showed that all mentioned characteristics decreased significantly (P<0.01 in the presence of soil residue of the herbicide. Increasing Idosulfuron-mesosulfurun residual concentration in soil decreased emergence and shoot and root biomass production. Bean had the lowest shoot (44% and root (66.78% biomass loss and tomato had the highest shoot (96.38% and root (89.64% biomass loss. Based on ED50 index, pea (0.0079 mg/kg soil was the most tolerant and tomato (0.0003 mg/kg soil was the most susceptible crop to soil residues of Idosulfuron-mesosulfurun, and other crops ranked in between as: tomato< sugarbeet< rapeseed< lentil< bean< pea. In general, these results showed that soil residue of Idosulfuron-mesosulfurun can injure rotation crops and it is important to consider their sensitivity in rotation programming.

Effects of an environmentally-relevant mixture of pyrethroid insecticides on spontaneous activity in primary cortical networks on microelectrode arrays.

Science.gov (United States)

Johnstone, Andrew F M; Strickland, Jenna D; Crofton, Kevin M; Gennings, Chris; Shafer, Timothy J

2017-05-01

Pyrethroid insecticides exert their insecticidal and toxicological effects primarily by disrupting voltage-gated sodium channel (VGSC) function, resulting in altered neuronal excitability. Numerous studies of individual pyrethroids have characterized effects on mammalian VGSC function and neuronal excitability, yet studies examining effects of complex pyrethroid mixtures in mammalian neurons, especially in environmentally relevant mixture ratios, are limited. In the present study, concentration-response functions were characterized for five pyrethroids (permethrin, deltamethrin, cypermethrin, β-cyfluthrin and esfenvalerate) in an in vitro preparation containing cortical neurons and glia. As a metric of neuronal network activity, spontaneous mean network firing rates (MFR) were measured using microelectorde arrays (MEAs). In addition, the effect of a complex and exposure relevant mixture of the five pyrethroids (containing 52% permethrin, 28.8% cypermethrin, 12.9% β-cyfluthrin, 3.4% deltamethrin and 2.7% esfenvalerate) was also measured. Data were modeled to determine whether effects of the pyrethroid mixture were predicted by dose-addition. At concentrations up to 10μM, all compounds except permethrin reduced MFR. Deltamethrin and β-cyfluthrin were the most potent and reduced MFR by as much as 60 and 50%, respectively, while cypermethrin and esfenvalerate were of approximately equal potency and reduced MFR by only ∼20% at the highest concentration. Permethrin caused small (∼24% maximum), concentration-dependent increases in MFR. Effects of the environmentally relevant mixture did not depart from the prediction of dose-addition. These data demonstrate that an environmentally relevant mixture caused dose-additive effects on spontaneous neuronal network activity in vitro, and is consistent with other in vitro and in vivo assessments of pyrethroid mixtures. Published by Elsevier B.V.

Effects of Bio-char on Soil Microbes in Herbicide Residual Soils

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WANG Gen-lin

2015-10-01

Full Text Available Effects of biological carbon (bio-char on soil microbial community were studied by pot experiments simulating long residual herbicide residues in soil environment, which clarifed the improvement of biochar and its structural properties on soil microenvironment. The results showed that fungi and actinomycetes had the same effect tendency within 0~0.72 mg·kg-1 in clomazone residue which increased the role of stimulation with crop growth process prolonged, especially in high residue treatment, but strong inhibitory effect on bacteria community was occured early which returned to normal until sugar beet growth to fiftieth day. Soil fungi community decreased with bio-char adding, but had no significant difference with the control. When clomazone residue in soil was below 0.24 mg·kg-1, soil actinomycetes community was higher than control without bio-char, bacteria increased first and then reduced after adding carbon as below 0.12 mg·kg-1. Biochar was ‘deep hole’ structure containing C, O, S and other elements. The results showed that a certain concentration clomazone residue in soil would stimulate soil fungi and actinomycetes to grow. After adding the biochar, the inhibition effect of high herbicides residual on bacterial would be alleviated.

Bioleaching of pollymetallic sulphide concentrate using thermophilic bacteria

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Vuković Milovan

2014-01-01

Full Text Available An extreme thermophilic, iron-sulphur oxidising bacterial culture was isolated and adapted to tolerate high metal and solids concentrations at 70°C. Following isolation and adaptation, the culture was used in a batch bioleach test employing a 5-l glass standard magnetic agitated and aerated reactor, for the bioleaching of a copper-lead-zinc collective concentrate. The culture exhibited stable leach performance over the period of leach operation and overall copper and zinc extractions higher than 97%. Lead sulphide is transformed into lead sulphate remaining in the bioleach residue due to the low solubility in sulphate media. Brine leaching of bioleach residue yields 95% lead extraction. [Projekat Ministarstva nauke Republike Srbije, br. 34023

Pyrethroids and DDT tolerance of Anopheles gambiae s.l. from Sengerema District, an area of intensive pesticide usage in north-western Tanzania.

Science.gov (United States)

Philbert, Anitha; Lyantagaye, Sylvester Leonard; Pradel, Gabriele; Ngwa, Che Julius; Nkwengulila, Gamba

2017-04-01

To assess the susceptibility status of malaria vectors to pyrethroids and dichlorodiphenyltrichloroethane (DDT), characterise the mechanisms underlying resistance and evaluate the role of agro-chemical use in resistance selection among malaria vectors in Sengerema agro-ecosystem zone, Tanzania. Mosquito larvae were collected from farms and reared to obtain adults. The susceptibility status of An. gambiae s.l. was assessed using WHO bioassay tests to permethrin, deltamethrin, lambdacyhalothrin, etofenprox, cyfluthrin and DDT. Resistant specimens were screened for knock-down resistance gene (kdr), followed by sequencing both Western and Eastern African variants. A gas chromatography-mass spectrophotometer (GC-MS) was used to determine pesticide residues in soil and sediments from mosquitoes' breeding habitats. Anopheles gambiae s.l. was resistant to all the insecticides tested. The population of Anopheles gambiae s.l was composed of Anopheles arabiensis by 91%. The East African kdr (L1014S) allele was found in 13 of 305 specimens that survived insecticide exposure, with an allele frequency from 0.9% to 50%. DDTs residues were found in soils at a concentration up to 9.90 ng/g (dry weight). The observed high resistance levels of An. gambiae s.l., the detection of kdr mutations and pesticide residues in mosquito breeding habitats demonstrate vector resistance mediated by pesticide usage. An integrated intervention through collaboration of agricultural, livestock and vector control units is vital. © 2017 John Wiley & Sons Ltd.

Polycyclic Aromatic Hydrocarbon Residues in Serum Samples of Autopsied Individuals from Tennessee

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Aramandla Ramesh

2014-12-01

Full Text Available This study reports the concentrations of Polycyclic Aromatic Hydrocarbons (PAHs in human blood sera samples (n = 650 obtained at autopsy from individuals who died of drug abuse, alcohol toxicity, homicide, suicide and other unknown causes. The analyzed samples from decedents revealed the presence of PAHs of which B(aP was the most predominant one, followed by benzo(bfluoranthene and benzo(kfluoranthene. The other PAHs detected sporadically and measured were benzo(g,h,iperylene, acenaphthene, anthracene, phenanthrene, and fluoranthene The mean concentrations of PAHs were greater in the twenties to fifties age groups compared to others. The PAH residue levels detected were high in African Americans compared to Caucasians, Asians, and Hispanics. It appears that environmental exposure, dietary intake and in some cases occupational exposure may have contributed to the PAH body burden. While the PAH residue concentrations measured fall within the range of those reported for healthy adults elsewhere, in isolated cases, the concentrations detected were high, calling the need for a reduction in PAH emissions and human biomonitoring studies for purposes of risk assessment.

Studies of pirimiphos-methyl residues in stored rice, using 14C-pirimiphos-methyl

International Nuclear Information System (INIS)

Varca, L.M.; Sanchez, T.E.; Gambalan, N.; Magallona, E.D.

1990-01-01

The distribution and persistence of pirimiphos-methyl on rice (hulled and unhulled) stored over a period of 6 months at 30 deg. C and about 11% moisture were studied using 14 C labelled insecticide. The procedures used for preparing the labelled formulation, applying the insecticide and for the handling and analysis of the grain samples were similar to those described for fenvalerate, see Varca, Sanchez and Magallona, ''Isotopic tracer aided studies of fenvalerate residues in stored products'', these Proceedings. After applying the pirimiphos-methyl, a concentration equal to 0.87 ppm was found on the hulled rice immediately after application; this concentration declined to 0.60 ppm after 6 months of storage. Over 28% of the residue was present in the seed in the methanol extractable form, and 38% was found on the surface at the end of the storage period. For the unhulled rice, most of the residue was retained in the hull with no decrease in the overall level during the storage period. (author)

MARKET BASKET SURVEY FOR SOME PESTICIDES RESIDUES IN FRUITS AND VEGETABLES FROM GHANA

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Crentsil Kofi Bempah

2012-12-01

Full Text Available A study was conducted to investigate the organochlorine, organophosphorus and synthetic pyrethroid pesticide residues in fruits and vegetables from markets in Ghana. For this purpose, a total of 309 fruits and vegetable samples, were collected and analyzed by gas chromatography with electron capture detector. The obtained results showed that the predominance of organochlorine followed by organophosphorus and synthetic pyrethroid pesticides in most of the analyzed samples. The detected concentrations of them were most significant in vegetable samples. The results obtained showed that 39.2 % of the fruits and vegetable samples analyzed contained no detectable level of the monitored pesticides, 51.0 % of the samples gave results with trace levels of pesticide residues below the maximum residue limit (MRL, while 9.8 % of the samples were above the MRL. The findings point to the urgent need to establish reliable monitoring programs for pesticides, so that any exceedance in concentration over environmental quality standards can be detected and appropriate actions taken.

Effects of dressing and cooking on DDT concentrations in certain fish from Lake Michigan

Science.gov (United States)

Reinert, Robert E.; Stewart, Donald; Seagran, Harry L.

1972-01-01

Concentrations of DDT residues were highest in parts of the body with the highest oil content in four species of fish from Lake Michigan: yellow perch (Perca flavescens), bloater (Coregonus hoyi), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch). Dressing reduced the DDT residues and oil content by more than 90% in yellow perch but had little effect in the other three species. The concentration of DDT residues in bloaters was changed little by smoking but was reduced 64–72% by other methods of cooking: from 8.0 ppm (raw) to 2.2 ppm after frying in corn oil; from 10.7 to 3.9 ppm after frying in lard; and from 9.1 to 3.2 ppm after broiling. The concentration of DDT residues in fillets of yellow perch changed only from 0.3 ppm (raw) to 0.4 or 0.5 ppm after baking, frying, or broiling.

Effects of Insecticides on Strawberry Aphid Chaetosiphon fragaefolii (Cockerell on Resistant and Susceptible Strawberry Genotypes

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Slobodan Milenković

2011-01-01

Full Text Available Strawberry aphid, Chaetosiphon fragaefolii (Cockerell, is the most important vector ofstrawberry virus. Breeding of genotypes resistant to this pest is an important preventivecontrol measure, which can be compatible with rational insecticide application. The aimof the paper was to determine effects of dimethoate and deltamethrin on C. fragaefoliipopulations reared on two strawberry genotypes different in susceptibility: susceptiblestrawberry cultivar Čačanska rana and medium resistant hybrid, zf/1/94/96 (Senga Fructarinax Del Norte. Lower toxicity of deltamethrin was observed (laboratory assay as well aslower biological efficacy of dimethoate at lower concentrations (field trial for specimensfrom C. fragaefolii population reared on susceptible strawberry cultivar Čačanska rana.

Anopheles darlingi and Anopheles marajoara (Diptera: Culicidae susceptibility to pyrethroids in an endemic area of the Brazilian Amazon

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Allan Kardec Ribeiro Galardo

2015-12-01

Full Text Available Abstract: INTRODUCTION: This study aimed to evaluate the susceptibility of Anopheles darlingi Root (1926 and Anopheles marajoara Galvão & Damasceno (1942 to pyrethroids used by the National Malaria Control Program in Brazil. METHODS: Mosquitoes from Amapá, Brazilian Amazon, were assessed for resistance to cypermethrin, deltamethrin, and alpha-cypermethrin. Insecticide-impregnated bottles were used as suggested by the CDC/Atlanta. RESULTS: Diagnostic dose for Anopheles darlingi was 12.5µg/bottle during 30 min of exposure. Concentrations for Anopheles marajoara were 20µg/bottle of cypermethrin and deltamethrin and 12.5µg/bottle of alpha-cypermethrin. CONCLUSIONS : No resistance was recorded for Anopheles darlingi , but Anopheles marajoara requires attention.

Evaluation of the mercaptobenzothiazole degradation by combined adsorption process and Fenton reaction using iron mining residue.

Science.gov (United States)

Martins, Adriana Lau da Silva; Teixeira, Luís Alberto César; da Fonseca, Fabiana Valéria; Yokoyama, Lídia

2017-08-01

The present study investigated the degradation of mercaptobenzothiazole (MBT), evaluating homogeneous and heterogeneous systems. An iron mineral residue from the desliming step of iron mining was used as a source in the Fenton-like reaction (advanced oxidation process). A granulometric analysis of the residue was performed and yielded fractions with high hematite (Fe 2 O 3 ) and low quartz content in sieves from 74 to below 44 mm. In this particle size range, the hematite content from 58.9% to 67.4% and the Brunauer-Emmett-Teller area from 0.1345 to 1.3137 m 2  g -1 were obtained. The zeta potential curves as a function of pH were obtained for the residue, the MBT solution and mixtures thereof. The adsorption of MBT in the residue and its degradation through the Fenton-like reaction were investigated. Adsorption tests and the Fenton-like reaction were carried out, where the MBT species and the residue are oppositely charged, yielding, respectively, 10% MBT adsorption on the surface of the residue and 100% MBT degradation by the Fenton-like reaction at pH 3, hydrogen peroxide concentration of 25 mg L -1 , residue concentration of 3 g L -1 , 200 rpm and 25°C, from a 100 mg L -1 MBT solution. MBT degradation was found to occur mainly by the heterogeneous Fenton-like process.

Characteristics of purple nonsulfur bacteria grown under Stevia residue extractions.

Science.gov (United States)

Xu, J; Feng, Y; Wang, Y; Lin, X

2013-11-01

As a consequence of the large-scale cultivation of Stevia plants, releases of plant residues, the byproduct after sweetener extraction, to the environment are inevitable. Stevia residue and its effluent after batching up contain large amounts of organic matters with small molecular weight, which therefore are a potential pollution source. Meanwhile, they are favourite substrates for micro-organism growths. This investigation was aimed to utilize the simulated effluent of Stevia residue to enrich the representative purple nonsulfur bacterium (PNSB), Rhodopseudomonas palustris (Rps. palustris), which has important economic values. The growth profile and quality of Rps. palustris were characterized by spectrophotometry, compared to those grown in common PNSB mineral synthetic medium. Our results revealed that the simulated effluent of Stevia residue not only stimulated Rps. palustris growth to a greater extent, but also increased its physiologically active cytochrome concentrations and excreted indole-3-acetic acid (IAA) content. This variation in phenotype of Rps. palustris could result from the shift in its genotype, further revealed by the repetitive sequence-based PCR (rep-PCR) fingerprinting analysis. Our results showed that the effluent of Stevia residue was a promising substrate for microbial growth. © 2013 The Society for Applied Microbiology.

Evidence that agricultural use of pesticides selects pyrethroid resistance within Anopheles gambiae s.l. populations from cotton growing areas in Burkina Faso, West Africa.

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Aristide Sawdetuo Hien

Full Text Available Many studies have shown the role of agriculture in the selection and spread of resistance of Anopheles gambiae s.l. to insecticides. However, no study has directly demonstrated the presence of insecticides in breeding sources as a source of selection for this resistance. It is in this context that we investigated the presence of pesticide residues in breeding habitats and their formal involvement in vector resistance to insecticides in areas of West Africa with intensive farming. This study was carried out from June to November 2013 in Dano, southwest Burkina Faso in areas of conventional (CC and biological cotton (BC growing. Water and sediment samples collected from breeding sites located near BC and CC fields were submitted for chromatographic analysis to research and titrate the residual insecticide content found there. Larvae were also collected in these breeding sites and used in toxicity tests to compare their mortality to those of the susceptible strain, Anopheles gambiae Kisumu. All tested mosquitoes (living and dead were analyzed by PCR for species identification and characterization of resistance genes. The toxicity analysis of water from breeding sites showed significantly lower mortality rates in breeding site water from biological cotton (WBC growing sites compared to that from conventional cotton (WCC sites respective to both An. gambiae Kisumu (WBC: 80.75% vs WCC: 92.75% and a wild-type strain (49.75% vs 66.5%. The allele frequencies L1014F, L1014S kdr, and G116S ace -1R mutations conferring resistance, respectively, to pyrethroids and carbamates / organophosphates were 0.95, 0.4 and 0.12. Deltamethrin and lambda-cyhalothrin were identified in the water samples taken in October/November from mosquitoes breeding in the CC growing area. The concentrations obtained were respectively 0.0147ug/L and 1.49 ug/L to deltamethrin and lambdacyhalothrin. Our results provided evidence by direct analysis (biological and chromatographic tests

Thermal Aging Effects on Residual Stress and Residual Strain Distribution on Heat Affected Zone of Alloy 600 in Dissimilar Metal Weld

Energy Technology Data Exchange (ETDEWEB)

Ham, Junhyuk; Choi, Kyoung Joon; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of)

2016-10-15

Dissimilar metal weld (DMW), consisting of Alloy 600, Alloy 182, and A508 Gr.3, has been widely used as a joining material of the reactor pressure vessel penetration nozzle and the steam generator tubing for pressurized water reactors (PWR) because of its good mechanical strength, thermal conductivity, and corrosion resistance. Residual tensile stress is mainly nominated as a cause of SCC in light water reactors by IAEA report. So, to relax the residual stress, post-weld heat treatment is required after manufacturing process such as welding. However, thermal treatment has a great effect on the microstructure and the chromium depletion profile on Alloy 600, so called sensitization. By this reason, HAZ on Alloy 600 is critical to crack. According to G.A. Young et al., Crack growth rates (CGR) in the Alloy 600 HAZ were about 30 times faster than those in the Alloy 600 base metal tested under the same conditions. And according to Z.P. Lu et al., CGR in the Alloy 600 HAZ can be more than 20 times higher than that in its base metal. There are some methods to measure the exact value of residual stress on the material surface. The most common way is X-ray diffraction method (XRD). The principle of XRD is based on lattice strains and depends on the changes in the spacing of the atomic planes in material. And there is a computer simulation method to estimate residual stress distribution which is called ANSYS. This study was conducted to investigate how thermal aging affects residual stress and residual strain distribution of Alloy 600 HAZ. Following conclusions can be drawn from this study. According to preceding researches and this study, both the relaxation of residual stress and the change of residual strain follow as similar way, spreading out from concentrated region. The result of Vickers micro-hardness tester shows that tensile residual stresses are distributed broadly on the material aged by 15 years. Therefore, HT400{sub Y}15 material is weakest state for PWSCC. The

Recycling of porcelain tile polishing residue in portland cement: hydration efficiency.

Science.gov (United States)

Pelisser, Fernando; Steiner, Luiz Renato; Bernardin, Adriano Michael

2012-02-21

Ceramic tiles are widely used by the construction industry, and the manufacturing process of ceramic tiles generates as a major residue mud derived from the polishing step. This residue is too impure to be reused in the ceramic process and is usually discarded as waste in landfills. But the analysis of the particle size and concentration of silica of this residue shows a potential use in the manufacture of building materials based on portland cement. Tests were conducted on cement pastes and mortars using the addition of 10% and 20% (mass) of the residue. The results of compressive strength in mortars made up to 56 days showed a significant increase in compressive strength greater than 50%. The result of thermogravimetry shows that portlandite is consumed by the cement formed by the silica present in the residue in order to form calcium silicate hydrate and featuring a pozzolanic reaction. This effect improves the performance of cement, contributes to research and application of supplementary cementitious materials, and optimizes the use of portland cement, reducing the environmental impacts of carbon dioxide emissions from its production.

Persistent Organochlorine Pesticide Residues in Some Selected Cocoa Beverages in Nigeria

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Olayinka A. Ibigbami

2017-12-01

Full Text Available This study evaluates the quality of the cocoa beverages produced in Nigeria with respect to the occurrence and levels of organochlorine pesticides OCPs residues in order to ascertain the potential health risks to the general public. Seven cocoa-based beverages were analysed for 17 OCP residues using gas chromatography coupled with an Electron Captured Detector (GC-ECD after extraction and silica-gel clean-up. The study reveals the presence of ten OCP residues in the cocoa beverages, with a concentration range from not detected ND—0.256 mg/kg, while α-BHC, β-BHC, methoxychlor, p,p′-DDE, dieldrin, endrin aldehyde, and endosulfan sulphate were not detected in any of the analysed samples. The contamination pattern of OCPs in the beverages was in the following order: Ovaltine > Milo > Cadbury-choco > Bournvita > Cowbell-coffee > Richoco > Oluji, with p,p′-DDT being the most frequently found pesticide. Heptachlor and endosulfan II showeda residual level above the European Union (EU Maximum Residual Limits (MRLs in only one sample.

Manual for implementing residual radioactive material guidelines using RESRAD, Version 5.0

Energy Technology Data Exchange (ETDEWEB)

Yu, C.; Zielen, A.J.; Cheng, J.J. [and others

1993-09-01

This manual presents information for implementing US Department of Energy (DOE) guidelines for residual radioactive material. It describes the analysis and models used to derive site-specific guidelines for allowable residual concentrations of radionuclides in soil and the design and use of the RESRAD computer code for calculating doses, risks, and guideline values. It also describes procedures for implementing DOE policy for reducing residual radioactivity to levels that are as low as reasonably achievable. Two new pathways, radon inhalation and soil ingestion, have been added to RESRAD. Twenty-seven new radionuclides have also been added, and the cutoff half-life for associated radionuclides has been reduced to six months. Other major improvements to the RESRAD code include the ability to run sensitivity analyses, the addition of graphical output, user-specified dose factors, updated databases, an improved groundwater transport model, optional input of a groundwater concentration and a solubility constant, special models for tritium and carbon-14, calculation of cancer incidence risk, and the use of a mouse with menus.

Manual for implementing residual radioactive material guidelines using RESRAD, Version 5.0

International Nuclear Information System (INIS)

Yu, C.; Zielen, A.J.; Cheng, J.J.

1993-09-01

This manual presents information for implementing US Department of Energy (DOE) guidelines for residual radioactive material. It describes the analysis and models used to derive site-specific guidelines for allowable residual concentrations of radionuclides in soil and the design and use of the RESRAD computer code for calculating doses, risks, and guideline values. It also describes procedures for implementing DOE policy for reducing residual radioactivity to levels that are as low as reasonably achievable. Two new pathways, radon inhalation and soil ingestion, have been added to RESRAD. Twenty-seven new radionuclides have also been added, and the cutoff half-life for associated radionuclides has been reduced to six months. Other major improvements to the RESRAD code include the ability to run sensitivity analyses, the addition of graphical output, user-specified dose factors, updated databases, an improved groundwater transport model, optional input of a groundwater concentration and a solubility constant, special models for tritium and carbon-14, calculation of cancer incidence risk, and the use of a mouse with menus

Compositional analysis and projected biofuel potentials from common West African agricultural residues

DEFF Research Database (Denmark)

Thomsen, Sune Tjalfe; Kádár, Zsófia; Schmidt, Jens Ejbye

2014-01-01

In recent years the focus on sustainable biofuel production from agricultural residues has increased considerably. However, the scientific work within this field has predominantly been concentrated upon bioresources from industrialised and newly industrialised countries, while analyses of the res......In recent years the focus on sustainable biofuel production from agricultural residues has increased considerably. However, the scientific work within this field has predominantly been concentrated upon bioresources from industrialised and newly industrialised countries, while analyses......, cassava stalks, plantain peelings, plantain trunks, plantain leaves, cocoa husks, cocoa pods, maize cobs, maize stalks, rice straw, groundnut straw and oil palm empty fruit bunches. The yam peelings showed the highest methane and bioethanol potentials, with 439 L methane (kg Total Solids)−1 and 0.61 L...... bioethanol (kg TS)−1 based on starch and cellulose alone due to their high starch content and low content of un-biodegradable lignin and ash. A complete biomass balance was done for each of the 13 residues, providing a basis for further research into the production of biofuels or biorefining from West...

The leaching kinetics of cadmium from hazardous Cu-Cd zinc plant residues.

Science.gov (United States)

Li, Meng; Zheng, Shili; Liu, Biao; Du, Hao; Dreisinger, David Bruce; Tafaghodi, Leili; Zhang, Yi

2017-07-01

A large amount of Cu-Cd zinc plant residues (CZPR) are produced from the hydrometallurgical zinc plant operations. Since these residues contain substantial amount of heavy metals including Cd, Zn and Cu, therefore, they are considered as hazardous wastes. In order to realize decontamination treatment and efficient extraction of the valuable metals from the CZPR, a comprehensive recovery process using sulfuric acid as the leaching reagent and air as the oxidizing reagent has been proposed. The effect of temperature, sulfuric acid concentration, particle size, solid/liquid ratio and stirring speed on the cadmium extraction efficiency was investigated. The leaching kinetics of cadmium was also studied. It was concluded that the cadmium leaching process was controlled by the solid film diffusion process. Moreover, the order of the reaction rate constant versus H 2 SO 4 concentration, particle size, solid/liquid ratio and stirring speed was calculated. The XRD and SEM-EDS analysis results showed that the main phases of the secondary sulfuric acid leaching residues were lead sulfate and calcium sulfate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leaching of copper concentrates using NaCl and soluble copper contributed by the own concentrate

International Nuclear Information System (INIS)

Herrero, O.; Bernal, N.; Quiroz, R.; Fuentes, G.; Vinals, J.

2005-01-01

Leaching of copper concentrates using cupric chloro complexes, generated in situ by the reaction between Cu(II), aported by the soluble copper content of the concentrate, and sodium chloride in acid media was studied. The concentrate samples were obtained from mineral processing plants from Antofagasta, Chile. Chemical and mineralogical characterization from original concentrates was made. Typical variable such as a chloride concentration, soluble copper concentration, leaching time, solid percentage and temperature were studied. DRX and EDS analyzed some of the residues. the experimental results indicated that it is possible to obtain solutions having high copper content (15 to 35 g/L) and 2 to 5 g/L free acid in order to submit this solution directly to a solvent extraction stage. The leaching tests use common reactive and low cost such as sodium chloride and sulfuric acid. (Author) 16 refs

A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk

Directory of Open Access Journals (Sweden)

Sagar Dhakal

2018-02-01

Full Text Available Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm−1 in water-tetracycline solutions and 1322 and 1621 cm−1 (shifted from 1317 and 1632 cm−1, respectively in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm−1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues.

A Simple Surface-Enhanced Raman Spectroscopic Method for on-Site Screening of Tetracycline Residue in Whole Milk.

Science.gov (United States)

Dhakal, Sagar; Chao, Kuanglin; Huang, Qing; Kim, Moon; Schmidt, Walter; Qin, Jianwei; Broadhurst, C Leigh

2018-02-01

Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS) method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm) and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm -1 in water-tetracycline solutions and 1322 and 1621 cm -1 (shifted from 1317 and 1632 cm -1 , respectively) in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm -1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues.

Uncovering the local inelastic interactions during manufacture of ductile cast iron: How the substructure of the graphite particles can induce residual stress concentrations in the matrix

Science.gov (United States)

Andriollo, Tito; Hellström, Kristina; Sonne, Mads Rostgaard; Thorborg, Jesper; Tiedje, Niels; Hattel, Jesper

2018-02-01

Recent X-ray diffraction (XRD) measurements have revealed that plastic deformation and a residual elastic strain field can be present around the graphite particles in ductile cast iron after manufacturing, probably due to some local mismatch in thermal contraction. However, as only one component of the elastic strain tensor could be obtained from the XRD data, the shape and magnitude of the associated residual stress field have remained unknown. To compensate for this and to provide theoretical insight into this unexplored topic, a combined experimental-numerical approach is presented in this paper. First, a material equivalent to the ductile cast iron matrix is manufactured and subjected to dilatometric and high-temperature tensile tests. Subsequently, a two-scale hierarchical top-down model is devised, calibrated on the basis of the collected data and used to simulate the interaction between the graphite particles and the matrix during manufacturing of the industrial part considered in the XRD study. The model indicates that, besides the viscoplastic deformation of the matrix, the effect of the inelastic deformation of the graphite has to be considered to explain the magnitude of the XRD strain. Moreover, the model shows that the large elastic strain perturbations recorded with XRD close to the graphite-matrix interface are not artifacts due to e.g. sharp gradients in chemical composition, but correspond to residual stress concentrations induced by the conical sectors forming the internal structure of the graphite particles. In contrast to common belief, these results thus suggest that ductile cast iron parts cannot be considered, in general, as stress-free at the microstructural scale.

Aerobic composting of digested residue eluted from dry methane fermentation to develop a zero-emission process.

Science.gov (United States)

Huang, Yu-Lian; Sun, Zhao-Yong; Zhong, Xiao-Zhong; Wang, Ting-Ting; Tan, Li; Tang, Yue-Qin; Kida, Kenji

2017-03-01

Digested residue remained at the end of a process for the production of fuel ethanol and methane from kitchen garbage. To develop a zero-emission process, the compostability of the digested residue was assessed to obtain an added-value fertilizer. Composting of the digested residue by adding matured compost and a bulking agent was performed using a lab-scale composting reactor. The composting process showed that volatile total solid (VTS) degradation mainly occurred during the first 13days, and the highest VTS degradation efficiency was about 27% at the end. The raw material was not suitable as a fertilizer due to its high NH 4 + and volatile fatty acids (VFAs) concentration. However, the composting process produced remarkable results; the physicochemical properties indicated that highly matured compost was obtained within 62days of the composting process, and the final N concentration, NO 3 - concentration, and the germination index (GI) at the end of the composting process was 16.4gkg -1 -TS, 9.7gkg -1 -TS, and 151%, respectively. Real-time quantitative PCR (qPCR) analysis of ammonia oxidizers indicated that the occurrence of nitrification during the composting of digested residue was attributed to the activity of ammonia-oxidizing bacteria (AOB). Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental determination of residual stress by neutron diffraction in a boiling water reactor core shroud

International Nuclear Information System (INIS)

Payzant, A.; Spooner, S.; Zhu, Xiaojing; Hubbard, C.R.

1996-01-01

Residual strains in a 51 mm (2-inch) thick 304L stainless steel plate have been measured by neutron diffraction and interpreted in terms of residual stress. The plate, measuring (300 mm) in area, was removed from a 6m (20-ft.) diameter unirradiated boiling water reactor core shroud, and included a multiple-pass horizontal weld which joined two of the cylindrical shells which comprise the core shroud. Residual stress mapping was undertaken in the heat affected zone, concentrating on the outside half of the plate thickness. Variations in residual stresses with location appeared consistent with trends expected from finite element calculations, considering that a large fraction of the residual hoop stress was released upon removal of the plate from the core shroud cylinder

Pharmacokinetics, efficacy prediction indexes and residue depletion of antibacterial drugs.

Directory of Open Access Journals (Sweden)

Arturo Anadón

2016-06-01

Full Text Available Pharmacokinetics behaviour of the antibacterial in food producing animals, provides information on the rates of absorption and elimination, half-life in plasma and tissue, elimination pathways and metabolism. The dose and the dosing interval of the antimicrobial can be justified by considering the pharmacokinetic/pharmacodynamic (PK/PD relationship, if established, as well as the severity of the disease, whereas the number of administrations should be in line with the nature of the disease. The target population for therapy should be well defined and possible to identify under field conditions. Based on in vitro susceptibility data, and target animal PK data, an analysis for the PK/PD relationship may be used to support dose regimen selection and interpretation criteria for a clinical breakpoint. Therefore, for all antibacterials with systemic activity, the MIC data collected should be compared with the concentration of the compound at the relevant biophase following administration at the assumed therapeutic dose as recorded in the pharmacokinetic studies. Currently, the most frequently used parameters to express the PK/PD relationship are Cmax/MIC (maximum serum concentration/MIC, %T > MIC (fraction of time in which concentration exceeds MIC and AUC/MIC (area under the inhibitory concentration– time curve/MIC. Furthermore, the pharmacokinetic parameters provide the first indication of the potential for persistent residues and the tissues in which they may occur. The information on residue depletion in food-producing animals, provides the data on which MRL recommendations will be based. A critical factor in the antibacterial medication of all food-producing animals is the mandatory withdrawal period, defined as the time during which drug must not be administered prior to the slaughter of the animal for consumption. The withdrawal period is an integral part of the regulatory authorities’ approval process and is designed to ensure that no

Dense medium ore concentrates of Bois-Noirs; Minerais des bois noirs, concentres de milieu dense

Energy Technology Data Exchange (ETDEWEB)

Le Bris, J; Leduc, M

1959-01-20

The chemical treatment of uranium concentrates of Bois-Noirs ore obtained by heavy medium are discussed. The first part deals with sulfuric acid attack on the concentrate, and the second part with the separation of the solution from residues by filtration. A third part deals with this separation by decantation. The fourth part deals with the carbonation of the pickling solutions obtained. (author) [French] Le present rapport est relatif a l'etude du traitement chimique de concentres uraniferes de minerais des Bois-Noirs obtenus par milieu dense. Une premiere partie est consacree a l'attaque sulfurique des concentres, une deuxieme partie a Ia separation de Ia solution d'attaque des residus par decantation. Une quatrieme partie a la carbonatation des solutions d'attaque obtenues. (auteur)

Metal releases from a municipal solid waste incineration air pollution control residue mixed with compost.

Science.gov (United States)

Van Praagh, M; Persson, K M

2008-08-01

The influence of 10 wt.% mature compost was tested on the heavy metal leachate emissions from a calcium-rich municipal solid waste incineration air pollution control residue (MSWI APC). Apart from elongated columns (500 and 1250 mm), an otherwise norm compliant European percolation test setup was used. More than 99% of the metals Al, As, Cd, Cr, Cu, Fe and Ni were left in the APC residue after leaching to a liquid-to-solid ratio (L/S) of 10. Apparent short-term effects of elevated leachate DOC concentrations on heavy metal releases were not detected. Zn and Pb leachate concentrations were one order of magnitude lower for L/S 5 and 10 from the pure APC residue column, which suggests a possible long-term effect of compost on the release of these elements. Prolonging the contact time between the pore water and the material resulted in elevated leachate concentrations at L/S 0.1 to L/S 1 by a factor of 2. Only Cr and Pb concentrations were at their maxima in the first leachates at L/S 0.1. Equilibrium speciation modelling with the PHREEQC code suggested portlandite (Ca(OH)2) to control Ca solubility and pH.

Lead and PCB's in canvasback ducks: Relationship between enzyme levels and residues in blood

Science.gov (United States)

Dieter, M.P.; Perry, M.C.; Mulhern, B.M.

1976-01-01

Blood samples were taken for two successive years from canvasback ducks trapped in the Chesapeake Bay. The first winter (1972?1973) five plasma enzymes known to respond to organochlorine poisoning were examined. Abnormal enzyme elevations suggested that 20% of the population sampled (23/115 ducks) might contain organochlorine contaminants, but no residue analyses were performed. The second winter (1974) two of the same enzymes, aspartate aminotransferase and lactate dehydrogenase, and a third enzyme known to be specifically inhibited by lead, delta-aminolevulinic acid dehydratase, were assayed in 95 blood samples. Blood residues of organochlorine compounds and of lead were determined in representative samples, and the correlations between residue levels and enzyme changes were examined. The enzyme bioassays in 1974 indicated that lead was a more prevalent environmental contaminant than organochlorine compounds in canvasback ducks; 17% of the blood samples had less than one-half of the normal delta-aminolevulinic acid dehydratase activity, but only 11% exhibited abnormal aspartate aminotransferase or lactate dehydrogenase activities. These findings were confirmed by residue analyses that demonstrated lead concentrations four times higher than background levels, but only relatively low organochlorine concentrations. There was a highly significant inverse correlation between delta-aminolevulinic acid dehydratase activity and blood lead concentrations (Pcontamination in waterfowl. In canvasback ducks 200 ppb of lead in the blood caused a 75% decrease in delta-aminolevulinic acid dehydratase activity, a magnitude of enzyme inhibition that disturbs heme synthesis and is regarded as detrimental in humans.

Residual effects of hypnotics: an update.

Science.gov (United States)

Hindmarch, I

1991-07-01

The sedative/hypnotic benzodiazepines introduced worldwide in the early 1960s were acclaimed for their low chemical toxicity and safety in clinical use. A decade later, some researchers and clinicians found that while all the drugs had undoubted potency and efficacy as sleep inducers and maintainers, the trade-off in residual effects (e.g., excessive daytime tiredness, poor concentration, impaired psychomotor performance, lowered mental abilities) was cause for concern. These sequelae not only affected patients' safety and ability to perform daytime tasks, but were also counter-therapeutic; the daytime sleep that was produced interfered with the natural nocturnal sleep. In a recent study, the degree to which patient abilities were impaired was measured by a number of psychomotor tests. Benzodiazepines with a duration of clinical effect of less than 8 to 10 hours produced fewer, less frequent residual effects than those with a measurable activity in excess of the normal nocturnal sleep period.

Levels and distribution of pesticide residues in soil and sediments in ...

African Journals Online (AJOL)

The concentrations of. DDT residues were greater in soil samples than in sediments. ... biodegradable and less persistent in the environment .... column containing a 0.45 µm filter into a vial ..... in the air around the Taihu Lake, China. Environ.

Contact irritant responses of Aedes aegypti Using sublethal concentration and focal application of pyrethroid chemicals.

Science.gov (United States)

Manda, Hortance; Shah, Pankhil; Polsomboon, Suppaluck; Chareonviriyaphap, Theeraphap; Castro-Llanos, Fanny; Morrison, Amy; Burrus, Roxanne G; Grieco, John P; Achee, Nicole L

2013-01-01

Previous studies have demonstrated contact irritant and spatial repellent behaviors in Aedes aegypti following exposure to sublethal concentrations of chemicals. These sublethal actions are currently being evaluated in the development of a push-pull strategy for Ae. aegypti control. This study reports on mosquito escape responses after exposure to candidate chemicals for a contact irritant focused push-pull strategy using varying concentrations and focal application. Contact irritancy (escape) behavior, knockdown and 24 hour mortality rates were quantified in populations of female Ae. aegypti under laboratory conditions and validated in the field (Thailand and Peru) using experimental huts. Evaluations were conducted using varying concentrations and treatment surface area coverage (SAC) of three pyrethroid insecticides: alphacypermethrin, lambacyhalothrin and deltamethrin. Under laboratory conditions, exposure of Ae. aegypti to alphacypermethrin using the standard field application rate (FAR) resulted in escape responses at 25% and 50% SAC that were comparable with escape responses at 100% SAC. Significant escape responses were also observed at time of exit (by four hours) and 40% increase in escape using ½FAR of alphacypermethrin at 75% SAC compared to a matched chemical-free control. In Peru, however, the maximum increase in Ae. aegypti escape from alphacypermethrin-treated huts was 11%. Results presented here suggest a potential role for sublethal and focal application of contact irritant chemicals in an Ae. aegypti push-pull strategy to reduce human-vector contact inside treated homes. However, the impact of an increase in escape response on dengue virus transmission is currently unknown and will depend on rate of biting on human hosts prior to house exiting.

On quantification of residual ink content and deinking efficiency in recycling of mixed office waste paper

Science.gov (United States)

Bo Li; Gaosheng Wang; Kefu Chen; David W. Vahey; Junyong Zhu

2011-01-01

Although (flotation) deinking has been a common industry practice for several decades, true residual ink content and deinking efficiency have never been quantified. Paper brightness and ERIC (Effective Residual Ink Concentration), based on measurements of the absorption coefficient of deinked pulp, have been used to determine performance of flotation deinking processes...

In vivo selection of resistant E. coli after ingestion of milk with added drug residues.

Directory of Open Access Journals (Sweden)

Richard Van Vleck Pereira

Full Text Available Antimicrobial resistance represents a major global threat to modern medicine. In vitro studies have shown that very low concentrations of drugs, as frequently identified in the environment, and in foods and water for human and animal consumption, can select for resistant bacteria. However, limited information is currently available on the in vivo impact of ingested drug residues. The objective of our study was to evaluate the effect of feeding preweaned calves milk containing antimicrobial drug residues (below the minimum inhibitory concentration, similar to concentrations detected in milk commonly fed to dairy calves, on selection of resistant fecal E. coli in calves from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR, and 15 calves were fed raw milk with drug residues (DR by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 µg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth prior to the first feeding in the trial (pre-treatment until 6 weeks of age. A significantly greater proportion of E. coli resistant to ampicillin, cefoxitin, ceftiofur, streptomycin and tetracycline was observed in DR calves when compared to NR calves. Additionally, isolates from DR calves had a significant decrease in susceptibility to ceftriaxone and ceftiofur when compared to isolates from NR calves. A greater proportion of E. coli isolates from calves in the DR group were resistant to 3 or more antimicrobial drugs when compared to calves in the ND group. These findings highlight the role that low concentrations of antimicrobial drugs have on the evolution and selection of resistance to multiple antimicrobial drugs in vivo.

A study on the production of agricultural residues in Italy

Energy Technology Data Exchange (ETDEWEB)

Di Blasi, C.; Tanzi, V.; Lanzetta, M. [Universita degli Studi di Napoli Federico II, Dip di Ingegneria Chimica, Napoli (Italy)

1997-12-01

The Italian production of agricultural residues has been evaluated with a view to energy recovery through gasification. Two main categories of residues have been identified: the first, (A) is associated with the growing and collection of products with a nutritional value, whereas the second (B) includes the residues associated with the subsequent processing in order to obtain final products for commercialization. Category A, which comprises three further sub-categories: straw (A1); woody residues (A2); and stems and leaves (residues from vegetables, tobacco, sugar beet, (A3)), results in about 16.5 mt yr. The average amount of straw (A1) is 11 mt/yr, of which about 60% is waste to be eliminated. Woody residues (A2) (mainly pruning off-cuts from vineyards and olive groves) are about 3.5 mt/yr (85% unused). Category A3 amounts to about 2 mt/yr (90% unused). Straw is available mainly in the northern part of the country, whereas the other two sub-categories are widely distributed in central and southern regions. The yields of category B are estimated at 4 mt/yr, of which more than 3 mt/yr are waste products from grape and olive processing. Other residues, such as rice, sunflower and soya-bean husks (about 0.65 mt/yr), almond and nut shells and fruit stones (about 0.2 mt/yr), although not widely available on a national scale, can be significant on a local basis. The total amount of unused agricultural residues is about 14.5 mt/yr, which, if completely exploited through gasification, can contribute as much as 7-10% to the current national electricity needs. The regions of Veneto, Puglia, Friuli, Lombardia and Emilia Romagna appear to be good candidates for electricity production, given the significant surface concentration of unused residues (105-55 t km{sup 2}). (author)

Polar drug residues in sewage and natural waters in the state of Rio de Janeiro, Brazil.

Science.gov (United States)

Stumpf, M; Ternes, T A; Wilken, R D; Rodrigues, S V; Baumann, W

1999-01-12

The drug residues of lipid regulators, anti-inflammatories and some drug metabolites have been detected in raw sewage, treated waste water and river water in the state of Rio de Janeiro, Brazil. These residues are mainly derived from humans via excretion. The median concentrations in the effluents of sewage treatment plants (STPs) of most drugs investigated in this study ranged from 0.1 to 1 microgram/l. The removal rates of individual drugs during passage through a Brazilian STP varied from 12 to 90%. As a consequence of the incomplete removal of these residues during passage through a STP, rivers were also found to be contaminated. Median concentrations ranged from between 0.02 and 0.04 microgram/l in river water, whereas the maximum values were observed to be up to 0.5 microgram/l.

Effectiveness of stress release geometries on reducing residual stress in electroforming metal microstructure

Science.gov (United States)

Song, Chang; Du, Liqun; Zhao, Wenjun; Zhu, Heqing; Zhao, Wen; Wang, Weitai

2018-04-01

Micro electroforming, as a mature micromachining technology, is widely used to fabricate metal microdevices in micro electro mechanical systems (MEMS). However, large residual stress in the local positions of the micro electroforming layer often leads to non-uniform residual stress distributions, dimension accuracy defects and reliability issues during fabrication of the metal microdevice. To solve this problem, a novel design method of presetting stress release geometries in the topological structure of the metal microstructure is proposed in this paper. First, the effect of stress release geometries (circular shape, annular groove shape and rivet shape) on the residual stress in the metal microstructure was investigated by finite element modeling (FEM) analysis. Two evaluation parameters, stress concentration factor K T and stress non-uniformity factor δ were calculated. The simulation results show that presetting stress release geometries can effectively reduce and homogenize the residual stress in the metal microstructures were measured metal microstructure. By combined use with stress release geometries of annular groove shape and rivet shape, the stress concentration factor K T and the stress non-uniformity factor δ both decreased at a maximum of 49% and 53%, respectively. Meanwhile, the average residual stress σ avg decreased at a maximum of 20% from  -292.4 MPa to  -232.6 MPa. Then, micro electroforming experiments were carried out corresponding to the simulation models. The residual stresses in the metal microstructures were measured by micro Raman spectroscopy (MRS) method. The results of the experiment proved that the stress non-uniformity factor δ and the average residual stress σ avg also decreased at a maximum with the combination use of annular groove shape and rivet shape stress release geometries, which is in agreement with the results of FEM analysis. The stress non-uniformity factor δ has a maximum decrease of 49% and the

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushed grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.

A survey of residual analysis and a new test of residual trend.

Science.gov (United States)

McDowell, J J; Calvin, Olivia L; Klapes, Bryan

2016-05-01

A survey of residual analysis in behavior-analytic research reveals that existing methods are problematic in one way or another. A new test for residual trends is proposed that avoids the problematic features of the existing methods. It entails fitting cubic polynomials to sets of residuals and comparing their effect sizes to those that would be expected if the sets of residuals were random. To this end, sampling distributions of effect sizes for fits of a cubic polynomial to random data were obtained by generating sets of random standardized residuals of various sizes, n. A cubic polynomial was then fitted to each set of residuals and its effect size was calculated. This yielded a sampling distribution of effect sizes for each n. To test for a residual trend in experimental data, the median effect size of cubic-polynomial fits to sets of experimental residuals can be compared to the median of the corresponding sampling distribution of effect sizes for random residuals using a sign test. An example from the literature, which entailed comparing mathematical and computational models of continuous choice, is used to illustrate the utility of the test. © 2016 Society for the Experimental Analysis of Behavior.

Evidence of precursor phenomena in the Kobe earthquake obtained from atmospheric radon concentration

Energy Technology Data Exchange (ETDEWEB)

Yasuoka, Yumi [Kobe Pharmaceutical University, 4-19-1 Mtoyamakitama-machi, Higashinada-ku, Kobe, Hyogo 658-8558 (Japan)]. E-mail: yasuoka@kobepharma-u.ac.jp; Igarashi, George [Science Research Center for Prediction of Earthquakes and Volcanic Eruptions, Tohoku University, 4-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 (Japan); Ishikawa, Testuo [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Tokonami, Shinji [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Shinogi, Masaki [Kobe Pharmaceutical University, 4-19-1 Mtoyamakitama-machi, Higashinada-ku, Kobe, Hyogo 658-8558 (Japan)

2006-06-15

Atmospheric {sup 222}Rn concentrations were determined over a 10a period, which included the date of the Kobe, Japan earthquake, on January 17th 1995. It was found that the seismically related {sup 222}Rn anomaly was higher than the 99% confidence limits for the residual value of atmospheric {sup 222}Rn which had been observed 2 months before. The residual {sup 222}Rn concentration, in which residual values of the daily minimum are the difference between each normal {sup 222}Rn concentration (calculated from January 1984 to December 1993) and the daily minimum {sup 222}Rn concentration (January 1994 to January 1995), was calculated by applying the exponential smoothing method to the residual values for each day. It was found that the fluctuations of the residual values can be fitted very well to a log-periodic oscillation model. The real residual values stopped increasing at 1994.999 (December 31st 1994), which corresponds with the critical point (t {sub c}) of best fit model. This anomalous {sup 222}Rn variation can be seen as the result of local stresses, not primary stresses which directly lead to the Kobe earthquake. On the other hand, when the critical exponent (z) and the radial frequency ({omega}) of the model were simultaneously fixed 0.2 {<=} z {<=} 0.6 and 6 {<=} {omega} {<=} 12, t {sub c} (critical point) was between January 13th 1995 and January 27th 1995. The Kobe earthquake occurrence date (January 17th 1995) is within this range. Therefore this anomalous {sup 222}Rn variation can also be seen as the result of primary stresses which possibly led to the Kobe earthquake. There is a distinct possibility that similar statistical oscillations will be detected in other measurements such as microseismicity, tectonic strain, fluctuation in the ground level, or changes in groundwater elevations and composition.

Hydrochloric acid leach of Agnew Lake uranium concentrate

International Nuclear Information System (INIS)

Haque, K.E.; Ipekoglue, B.

1981-10-01

Hydrochloric acid leaching was conducted on the radioactive mineral concentrate separated from the Agenw Lake uranium ore. Leach tests conducted at the optimum conditions (75 0 C; 36 hours; 66.0 Kg HCl/tonne; solid:liquid -1:1) resulted in the extraction of 87% uranium and 84% radium. The radionuclide level of the residue was U-0.016%, Th-0.24% and Ra-65 pCi/g solids. However to obtain a residue almost free of radium (i.e., Ra level at the detection limit: 4-6 pCi/g solids), the first stage leach residue was further treated with hydrochloric acid. The radium level in the best second stage leach residue was also above the target level. Therefore, multistage (3 or 4) hydrochloric acid and/or neutral chloride leaching is recommended to obtain tailings almost free of radionuclide

Petroleum residue upgrading with dispersed catalysts: Part 2. Effect of operating conditions

Energy Technology Data Exchange (ETDEWEB)

Panariti, N.; Del Bianco, A.; Del Piero, G. [ENITECNOLOGIE S.p.A, Via Maritano 26, 20097 San Donato Mil (Italy); Marchionna, M. [SNAMPROGETTI S.p.A, Via Maritano 26, 20097 San Donato Mil (Italy); Carniti, P. [Universita degli Studi di Milano, Dip. Chimica Fisica ed Elettrochimica, Via Celoria 20, Milan (Italy)

2000-12-04

The hydrotreatment of a petroleum residue in the presence of dispersed molybdenite was carried out within a wide range of operating conditions and catalyst loading. The effect of reaction severity as well as of molybdenum concentration on product distribution and quality was studied. Based on the experimental results, a simplified reaction scheme was proposed. The hydroprocessing of the residue was described in terms of the competition between two reactions: the direct conversion of the feedstock to distillate and coke, and the catalytic hydrogenation. Compared to thermal conditions, the presence of dispersed molybdenite controls very well coke formation; however, a trend of increasing formation of solids was observed at high catalyst concentrations. The overall upgrading of the feedstock requires significant amounts of molybdenum as well as relatively high hydrogen pressure.

Evaluation of NORM residues in the Morro Redondo waterworks, Brazil

International Nuclear Information System (INIS)

Pinto, Michele C.F.; Rocha, Zildete

2007-01-01

Most mineral resources present naturally occurring radioactive material known by the acronym NORM. Some of them, specially those geological material originated from igneous rock present elevated radionuclides concentration. The exploration of these materials may elevate human exposure to the natural ionizing radiation, by removing them from the natural compartment or by increasing the radionuclides concentration in products, by products and more frequently in the industrial residues, these are referred as TENORM Technologically Enhanced NORM. The residues of the waterworks, especially those of the iron and manganese remotion are expected to contain radioactivity concentration due to geological reasons. The paper evaluates the natural radionuclide concentration in the waste water sludge of the iron removing process carried out by the Water Treatment Plant (WTP) - Morro Redondo waterwork operated by Companhia de Saneamento de Minas Gerais - COPASA. Such waterwork supplies drink water for more than 200.000 people, inhabitants of the south part of Belo Horizonte and Nova Lima. The water is extracted from three rock source formations in the iron quadrangle of Minas Gerais, namely Cercadinho, Fechos and Mutuca. The sludges samples analysed have shown values around 300 Bq kg -1 for 226 Ra, in radiological point of view, the most important radionuclide. Values taken from literature were considered - 10.000 Bq kg -1 are not rare, and the ones around 300 Bq kg -1 are normal. (author)

Rapid modified QuEChERS method for pesticides detection in honey by high-performance liquid chromatography UV-visible

Directory of Open Access Journals (Sweden)

Elisabetta Bonerba

2014-05-01

Full Text Available The extensive use of pesticides in agriculture plays an important role in bees die-off and allows the presence of residues in hive products, particularly in honey. An accurate and reliable analytical method, based on QuEChERS extractive technique, has been developed for the quantitative determination by high-performance liquid chromatography UV-visible detector of 5 pesticides (Deltamethrin, Dimethoate, Imidacloprid, Acetamiprid, Chlorfenvinphos in honey. The method, according to Commission Directive 2002/63/EC and Regulation 882/2004/EC, provided excellent results with respect to linearity (correlation coefficient up to 0.993, limits of detection and quantification (0.005 and 0.01 μg/mL for Dimethoate, Deltamethrin and Chlorfenvinphos; 0.02 and 0.05 μg/mL for Acetamiprid and Imidacloprid, recovery values (86.4 to 96.3%, precision and relative expanded uncertainty of a measurement, demonstrating the conformity of the this method with the European directives. The proposed method was applied to 23 samples of Apulian honey. None of the investigated pesticides was detected in these samples.

Influence of bleaching on flavor of 34% whey protein concentrate and residual benzoic acid concentration in dried whey products

Science.gov (United States)

Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

Influence of Bleaching on Flavor of 34% Whey Protein Concentrate and Residual Benzoic Acid Concentration in Dried Whey Proteins

Science.gov (United States)

Previous studies have shown that bleaching negatively affects the flavor of 70% whey protein concentrate (WPC70), but bleaching effects on lower-protein products have not been established. Benzoyl peroxide (BP), a whey bleaching agent, degrades to benzoic acid (BA) and may elevate BA concentrations...

Ways of solving the problem of NPP evaporate concentrate storage

International Nuclear Information System (INIS)

Dmitriev, S.A.; Lifanov, F.A.; Savkin, A.E.; Lashchenov, S.M.

2000-01-01

The use of next engineering operations: isotope separation using oxidation, filtration and selective sorption methods, hardening and long term secondary radioactive waste disposal (cement compound from filtration stage and depleted sorbent on filters); concentration and preparation of dry salts from the radionuclide-free stillage residues were proposed for NPP waste reprocessing. The laboratory and pilot tests that demonstrated the possibility for purification of NPP stillage residues from radionuclides to the levels less than maximum permissible ones were conducted. The purified stillage residues are sent for the burial after drying. The calculations of material flows are treated by the example of the Kursk NPP stillage residue and the scheme of the waste retrieval is given [ru

HPLC residues of enrofloxacin and ciprofloxacin in eggs of laying hens.

Science.gov (United States)

Gorla, N; Chiostri, E; Ugnia, L; Weyers, A; Giacomelli, N; Davicino, R; García Ovando, H

1997-05-01

Eggs of 12 laying hens with 5 mg/kg/day oral administration of 5% enrofloxacin (EFX) or ciprofloxacin (CFX) solution during 5 days contained residues from 0.02 to 1.98 microg/g (EFX) or 0.14 to 0.28 microg/g (CFX). At identical dosage regime High Performance Liquid Chromatograhy (HPLC) residues of EFX were 6-fold greater than CFX ones. Maximun concentrations were detected at the second day after the administration withdrawal. The limits of detection were 0.019 microg/g for EFX and 0.156 microg/g for CFX. The recovery was 36-50% for CFX and 49-85% for EFX. The withdrawal treatment periods in hens are six days for EFX and five days for CFX in order to avoid violative levels of egg residues.

Experimental evaluation of residual stresses produced by plain dents in pipelines

Energy Technology Data Exchange (ETDEWEB)

Pascotto, Jorge [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil); Marques, Altino; Fonseca, Maria Cindra [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

2009-07-01

A dent means a permanent plastic deformation of the circular cross-section of the pipe. Dents are potentially danger for structural integrity of onshore and offshore pipelines, because it causes a local stress and strain concentration. It is also expected that residual stresses are introduced by the non-uniform plastic deformation. A plain dent is a dent which causes a smooth change in the curvature of the pipe wall that contains no wall thickness reductions (such as a gouge or a crack) or other defects or imperfections (such as a weld). This work presents an experimental evaluation of residual stresses intensification due to plain dents introduced through the same indentation process, in samples made of the same steel line pipe, commonly used in the pipeline industry. The residual stresses were measured in the longitudinal and circumferential directions in preselected points by X-ray diffraction technique, before indentation. After the samples have been dented, the residual stresses were measured once more at the same points, for comparison. All samples presented a similar behavior of the residual stresses due to induced plain dents, and the X-ray diffraction technique shows itself as an efficient methodology of stress measurement in pipelines. (author)

Dynamic viscosity study of barley malt and chicory concentrates

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G. O. Magomedov

2016-01-01

Full Text Available The purpose of research is to find optimal conditions for dispersing and subsequent dehydration of liquid food environments in the nozzle spray drying chamber through the study of dynamic changes in viscosity according to temperature, velocities gradients and dry residue content. The objects of study were roasted chicory and malt barley concentrates with dry residue content of 20, 40, 60 and 80%. Research of dynamic viscosity were carried out at the measuring complex based on the rotational viscometer Rheotest II, analog-to-digital converter, module Laurent and a personal computer with a unique software that allows to record in real time (not only on a tape recorder, but also in the form of graphic files the behavior of the viscosity characteristics of concentrates. Registration of changes of dynamic viscosity was carried out at a shear rate gradient from 1,0 с -1 to 27,0 с -1 and the products temperature thermostating : 35, 55, 75˚ C. The research results are presented in the form of graphic dependences of effective viscosity on shear rate and flow curves (dependencies of shear stresses on the velocity gradient, which defined flow regimes, the optimal modes of dispersion concentrates into spray dryer chambers in obtaining of powdered semi-finished products and instanting were found: dry residue content - 40 %, concentrate temperature - 75 ˚C, velocity gradient in the air channel of the nozzle at least 20 c-1

Life cycle analysis of biogas from residues; Livscykelanalys av biogas fraan restprodukter

Energy Technology Data Exchange (ETDEWEB)

Tufvesson, Linda; Lantz, Mikael [Dep. for Miljoe- och Energisystem, Lunds Tekniska Hoegskola, Lund (Sweden)

2012-06-15

The purpose of this study is to carry out life cycle assessments for different biogas systems where biogas is produced from different residues. The investigated residues are distiller's waste, rapeseed cake, whey permeate, concentrated whey permeate, fodder milk, fish residues, bakery residues and glycerol. The environmental impact categories included are climate change, eutrophication, acidification, photochemical ozone creation potential, particles and energy balance. The calculations include emissions from technical systems, especially the energy input in various operations and processes. A general conclusion is that all studied residues are very well suited for production of biogas if there is no demand for them as animal feed today. All biogas systems also reduce the emissions of greenhouse gases compared to petrol and diesel and meet the requirements presented in the EU renewable energy directive (RED). The results of the study also show that the investigated biogas systems are complex and many different parameters affect the result. These parameters are both integrated in the life cycle assessment method, but also in the inventory data used.

Evidence for the Induction of Key Components of the NOTCH Signaling Pathway via Deltamethrin and Azamethiphos Treatment in the Sea Louse Caligus rogercresseyi

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Sebastian Boltaña

2016-05-01

Full Text Available The extensive use of organophosphates and pyrethroids in the aquaculture industry has negatively impacted parasite sensitivity to the delousing effects of these antiparasitics, especially among sea lice species. The NOTCH signaling pathway is a positive regulator of ABC transporter subfamily C expression and plays a key role in the generation and modulation of pesticide resistance. However, little is known about the molecular mechanisms behind pesticide resistance, partly due to the lack of genomic and molecular information on the processes involved in the resistance mechanism of sea lice. Next-generation sequencing technologies provide an opportunity for rapid and cost-effective generation of genome-scale data. The present study, through RNA-seq analysis, determined that the sea louse Caligus rogercresseyi (C. rogercresseyi specifically responds to the delousing drugs azamethiphos and deltamethrin at the transcriptomic level by differentially activating mRNA of the NOTCH signaling pathway and of ABC genes. These results suggest that frequent antiparasitic application may increase the activity of inhibitory mRNA components, thereby promoting inhibitory NOTCH output and conditions for increased resistance to delousing drugs. Moreover, data analysis underscored that key functions of NOTCH/ABC components were regulated during distinct phases of the drug response, thus indicating resistance modifications in C. rogercresseyi resulting from the frequent use of organophosphates and pyrethroids.

Effect of applied stress on the compressive residual stress introduced by laser peening

International Nuclear Information System (INIS)

Sumiya, Rie; Tazawa, Toshiyuki; Narazaki, Chihiro; Saito, Toshiyuki; Kishimoto, Kikuo

2016-01-01

Peening is the process which is able to be generated compressive residual stress and is known to be effective for preventing SCC initiation and improvement of fatigue strength. Laser peening is used for the nuclear power plant components in order to prevent SCC initiation. Although it is reported that the compressive residual stress decreases due to applied stresses under general operating condition, the change of residual stress might be large under excessive loading such as an earthquake. The objectives of this study are to evaluate the relaxation behavior of the compressive residual stress due to laser peening and to confirm the surface residual stress after loading. Therefore laser peened round bar test specimens of SUS316L which is used for the reactor internals of nuclear power plant were loaded at room temperature and elevated temperature and then surface residual stresses were measured by X-ray diffraction method. In the results of this test, it was confirmed that the compressive residual stress remained after applying uniform stress larger than 0.2% proof stress, and the effect of cyclic loading on the residual stress was small. The effect of applying compressive stress on the residual stress relaxation was confirmed to be less than that of applying tensile stress. Plastic deformation through a whole cross section causes the change in the residual stress distribution. As a result, the surface compressive residual stress is released. It was shown that the effect of specimen size on residual stress relaxation and the residual stress relaxation behavior in the stress concentration region can be explained by assumed stress relaxation mechanism. (author)

Determination of the Minimum Inhibitory Concentration of the Barberry Extract and the Dried Residue of Red Grape and Their Effects on the Growth Inhibition of Sausage Bacteria by Using Response Surface Methodology (RSM

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Fatemeh Riazi

2015-09-01

Full Text Available Background and Objectives: With regard to the hazards of nitrite, application of natural preservatives in order to reduce the microbial load of meat and meat products is increasing. Owing to their anti-bacterial properties, red barberry and the dried residue of red grape could be suitable replacers for nitrite. Materials and Methods: Agar dilution method was employed in order to determine the minimum inhibitory concentration (MIC of the barberry extract and the dried residue of red grape. The anti-microbial effects of the barberry extract (0-600 mg/kg, the dried residue of red grape (0-2% and nitrite (30-90 mg/kg were investigated on the total viable counts of Clostridium perfringens, as well as on the psychrophilic bacteria after 30 days of storage at 4°C. Finally, the effects of the three independent variables in the optimal sample were examined on the growth of the inoculated C. perfringens. Results: The MIC of the barberry extract and the dried residue of red grape on Staphylococcus aureus was 3 and 6 (mg/ml, respectively. In the case of Escherichia coli, it was 4 and 7 (mg/ml, respectively. The barberry extract and nitrite reduced the growth of the living aerobic bacteria significantly. The spores of the inoculated C. perfringens had no growth in the optimum sample during storage. Conclusions: The barberry extract and the dried residue of red grape as natural preservatives, could partially substitute for nitrite in order to reduce the microbial load of sausage.

Maximizing Selective Cleavages at Aspartic Acid and Proline Residues for the Identification of Intact Proteins

Science.gov (United States)

Foreman, David J.; Dziekonski, Eric T.; McLuckey, Scott A.

2018-04-01

A new approach for the identification of intact proteins has been developed that relies on the generation of relatively few abundant products from specific cleavage sites. This strategy is intended to complement standard approaches that seek to generate many fragments relatively non-selectively. Specifically, this strategy seeks to maximize selective cleavage at aspartic acid and proline residues via collisional activation of precursor ions formed via electrospray ionization (ESI) under denaturing conditions. A statistical analysis of the SWISS-PROT database was used to predict the number of arginine residues for a given intact protein mass and predict a m/z range where the protein carries a similar charge to the number of arginine residues thereby enhancing cleavage at aspartic acid residues by limiting proton mobility. Cleavage at aspartic acid residues is predicted to be most favorable in the m/z range of 1500-2500, a range higher than that normally generated by ESI at low pH. Gas-phase proton transfer ion/ion reactions are therefore used for precursor ion concentration from relatively high charge states followed by ion isolation and subsequent generation of precursor ions within the optimal m/z range via a second proton transfer reaction step. It is shown that the majority of product ion abundance is concentrated into cleavages C-terminal to aspartic acid residues and N-terminal to proline residues for ions generated by this process. Implementation of a scoring system that weights both ion fragment type and ion fragment area demonstrated identification of standard proteins, ranging in mass from 8.5 to 29.0 kDa. [Figure not available: see fulltext.

Evaluation of residue-residue contact predictions in CASP9

KAUST Repository

Monastyrskyy, Bohdan; Fidelis, Krzysztof; Tramontano, Anna; Kryshtafovych, Andriy

2011-01-01

This work presents the results of the assessment of the intramolecular residue-residue contact predictions submitted to CASP9. The methodology for the assessment does not differ from that used in previous CASPs, with two basic evaluation measures

Neonicotinoid residues in UK honey despite European Union moratorium.

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Ben A Woodcock

Full Text Available Due to concerns over negative impacts on insect pollinators, the European Union has implemented a moratorium on the use of three neonicotinoid pesticide seed dressings for mass-flowering crops. We assessed the effectiveness of this policy in reducing the exposure risk to honeybees by collecting 130 samples of honey from bee keepers across the UK before (2014: N = 21 and after the moratorium was in effect (2015: N = 109. Neonicotinoids were present in about half of the honey samples taken before the moratorium, and they were present in over a fifth of honey samples following the moratorium. Clothianidin was the most frequently detected neonicotinoid. Neonicotinoid concentrations declined from May to September in the year following the ban. However, the majority of post-moratorium neonicotinoid residues were from honey harvested early in the year, coinciding with oilseed rape flowering. Neonicotinoid concentrations were correlated with the area of oilseed rape surrounding the hive location. These results suggest mass flowering crops may contain neonicotinoid residues where they have been grown on soils contaminated by previously seed treated crops. This may include winter seed treatments applied to cereals that are currently exempt from EU restrictions. Although concentrations of neonicotinoids were low (<2.0 ng g-1, and posed no risk to human health, they may represent a continued risk to honeybees through long-term chronic exposure.

Anaerobic digestion of cider apple residues

Energy Technology Data Exchange (ETDEWEB)

Contreras Lopez, A. (E.T.S.I.I., U.N.E.D., Madrid (Spain). Dept. Quimica Applicada a la Ingenieria); Lopez Bobo, R. (E.T.S. Ingeneiros Industriales, Asturias (Spain). Dept. de Energia)

1992-12-01

Apple residue from the cider industry is used here for anaerobic fermentation. The effect of retention time and volatile solids concentration on the production of biogas and methane was investigated by using continuously mixed anaerobic fermentors with a working volume of 1 1. The maximum proportions of biogas and methane obtained were 430 1 biogas/kg per day (12 days' retention time and 3% of volatile solids) and 281 1 of methane per day (a retention time of 30 days and 2% of volatile solids), respectively. (author)

Depletion of eugenol residues from the skin-on fillet tissue of rainbow trout exposed to 14C-labeled eugenol

Science.gov (United States)

Meinertz, Jeffery R.; Schreier, Theresa M.; Porcher, Scott T.; Smerud, Justin R.; Gaikowski, Mark P.

2014-01-01

The U.S. is lagging in access to an approved immediate-release sedative, i.e. a compound that can be safely and effectively used to sedate fish and has no withdrawal period. AQUI-S® 20E (10% active ingredient, eugenol) is under investigation as an immediate-release sedative for freshwater finfish. Because of its investigational status, data are needed to characterize the depletion, distribution, and identity of AQUI-S® 20E residues in fillet tissue. Rainbow trout (Oncorhynchus mykiss) were exposed to uniformly ring labeled 14C-eugenol at a nominal concentration of 10 mg/L for 60 min in 18 °C water. Fish (n = 6) were sampled immediately after the exposure (0 min) then at 30, 60, 120, and 240 min. Eugenol concentrations and characterization of 14C residues in the fillet tissue were determined by high pressure liquid chromatography and flow-through liquid scintillation counting techniques. Total 14C-residue burdens in fillet tissue were determined by tissue oxidation and static liquid scintillation counting techniques. Maximum eugenol and 14C-eugenol equivalent residue concentrations in the fillet tissue were measured immediately after the exposure (44.5 and 38.8 μg/g, respectively). Eugenol was the primary 14C-residue (> 90% of all 14C-residues) in extracts from fillet tissue taken from fish sampled immediately after the exposure (0 min) and from fish sampled at 30 and 60 min after the exposure. The depletion of 14C-eugenol residues from the fillet tissue was rapid (t1/2 = 26.25 min) after transferring the exposed fish to fresh flowing water.

Assays of residual antibiotics after treatment of γ-ray and UV irradiation

International Nuclear Information System (INIS)

Shin, Ji Hye; Nam, Ji Hyun; Lee, Dong Hun; Yu, Seung Ho; Lee, Myun Joo

2010-01-01

The pollution of antibiotics is a major cause of spreading antibiotics resistant bacteria in the environment. Applications of ozonation, UV, and γ-ray irradiations have been introduced to remove antibiotics in the effluents from wastewater treatment system. In this study, we compared the chemical (HPLC) and biological (antimicrobial susceptibility test, AMS) assays in measuring of the concentrations of residual antibiotics after γ-ray and UV irradiation. Most samples were degraded by γ-ray irradiation (1 ∼ 2 kGy). However, lincomycin and tetracycline were not degraded by UV irradiation. The concentration of residual antibiotics, that was treated with γ-ray and UV irradiation, measuring by bioassay was similar to HPLC. The concentrations of γ-ray irradiated cephradine measured by AMS test were 2 times higher than of HPLC assay, indicating AMS test is more sensitive than HPLC assay. These results indicate that γ-ray irradiation technique is more useful than UV irradiation, and biological assay is more useful to detect the antibiotics and toxic intermediates in antibiotics degradation

Intake of Fruits and Vegetables with Low-to-Moderate Pesticide Residues Is Positively Associated with Semen-Quality Parameters among Young Healthy Men123

Science.gov (United States)

Gaskins, Audrey J; Williams, Paige L; Mendiola, Jaime; Levine, Hagai; Hauser, Russ; Swan, Shanna H; Chavarro, Jorge E

2016-01-01

Background: Numerous studies have shown that occupational or environmental pesticide exposure can affect male fertility. There is less evidence, however, regarding any potentially adverse effects of pesticide residues in foods on markers of male fertility potential. Objectives: We examined the relations between fruit and vegetable intake, considering pesticide residue status, and semen quality and serum concentrations of reproductive hormones in healthy young men. Methods: The Rochester Young Men's Study is a cross-sectional study that recruited men aged 18–22 y (n = 189) in Rochester, New York. Participants completed a questionnaire, provided a semen sample, had a blood sample drawn, and underwent a physical examination at enrollment. Semen samples were analyzed for total sperm count, sperm concentration, morphology, motility, ejaculate volume, total motile count, and total normal count. Dietary intake during the previous year was assessed by a validated food-frequency questionnaire. Fruit and vegetables were categorized as having high [Pesticide Residue Burden Score (PRBS) ≥4] or low-to-moderate (PRBS vegetable intake with semen variables and reproductive hormones while adjusting for potential confounding factors. Results: The total intake of fruit and vegetables was unrelated to semen quality. However, the intake of fruit and vegetables with low-to-moderate pesticide residues was associated with a higher total sperm count and sperm concentration, whereas the intake of fruit and vegetables with high pesticide residues was unrelated to semen quality. On average, men in the highest quartile of low-to-moderate-pesticide fruit and vegetable intake (≥2.8 servings/d) had a 169% (95% CI: 45%, 400%) higher total sperm count and a 173% (95% CI: 57%, 375%) higher sperm concentration than did men in the lowest quartile (vegetables, regardless of pesticide-residue status, was not associated with reproductive hormone concentrations. Conclusions: The consumption of fruit

Determination of oxytetracycline residues in cattle meat marketed in the Kilosa district, Tanzania

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Zuhura I. Kimera

2015-11-01

Full Text Available Oxytetracycline is used to treat various diseases in cattle. However, its use may be associated with unacceptable residue levels in food. Oxytetracycline residues in tissues from indigenous cattle were determined in a cross-sectional study conducted in the Kilosa district, Tanzania, between November 2012 and April 2013. A total of 60 tissue samples, including muscle, liver and kidney, were collected from slaughterhouses and butchers and analysed for oxytetracycline using high-performance liquid chromatography. Oxytetracycline residues were found in 71.1% of the samples, of which 68.3% were above acceptable regulatory levels. The mean concentration of oxytetracycline across tissues was 3401.1 μg/kg ± 879.3 μg/kg; concentrations in muscle, liver and kidney were 2604.1 μg/kg ± 703.7 μg/kg, 3434.4 μg/kg ± 606.4 μg/kg and 3533.1 μg/kg ± 803.6 μg/kg, respectively. High levels of oxytetracycline residue in meat from indigenous cattle may pose a health threat to consumers in Kilosa. The findings possibly reflect a general lack of implementation of recommended withdrawal periods, ignorance about drug use and lack of extension services. Strict regulation of the use of antimicrobial drugs in the livestock industry and associated testing of animal-derived food sources prior to marketing are required.

Determination of oxytetracycline residues in cattle meat marketed in the Kilosa district, Tanzania.

Science.gov (United States)

Kimera, Zuhura I; Mdegela, Robinson H; Mhaiki, Consolatha J N; Karimuribo, Esron D; Mabiki, Faith; Nonga, Hezron E; Mwesongo, James

2015-11-27

Oxytetracycline is used to treat various diseases in cattle. However, its use may be associated with unacceptable residue levels in food. Oxytetracycline residues in tissues from indigenous cattle were determined in a cross-sectional study conducted in the Kilosa district, Tanzania, between November 2012 and April 2013. A total of 60 tissue samples, including muscle, liver and kidney, were collected from slaughterhouses and butchers and analysed for oxytetracycline using high-performance liquid chromatography. Oxytetracycline residues were found in 71.1% of the samples, of which 68.3% were above acceptable regulatory levels. The mean concentration of oxytetracycline across tissues was 3401.1 μg/kg ± 879.3 μg/kg; concentrations in muscle, liver and kidney were 2604.1 μg/kg ± 703.7 μg/kg, 3434.4 μg/kg ± 606.4 μg/kg and 3533.1 μg/kg ± 803.6 μg/kg, respectively. High levels of oxytetracycline residue in meat from indigenous cattle may pose a health threat to consumers in Kilosa. The findings possibly reflect a general lack of implementation of recommended withdrawal periods, ignorance about drug use and lack of extension services. Strict regulation of the use of antimicrobial drugs in the livestock industry and associated testing of animal-derived food sources prior to marketing are required.

Pesticide residue assessment in three selected agricultural production systems in the Choluteca River Basin of Honduras

International Nuclear Information System (INIS)

Kammerbauer, J.; Moncada, J.

1999-01-01

There is a basic lack of information about the presence of pesticide residues in the environment in Central America. Over the period of February 1995 to June 1997, river, well, lagoon and spring water samples, as well as soil, fish tissue, lagoon bed sediments and some foodstuffs were taken from the greater Cholutecan River Basin of Honduras and analyzed for pesticide residues. These were collected at three separate sites (La Lima, Zamorano and Choluteca), each characterized by differing agricultural production systems. The main pesticide residues found in soil samples were dieldrin and p,p'-DDT, while river water samples were found to have detectable levels of heptachlor, endosulfan and chlorpyrifos, with lagoon and well water also being shown to contain heptachlor. These pesticides detected were in more than 20% of the samples assessed. In river water samples more pesticide residues at higher concentrations were found to be associated with areas of more intensive agricultural production. The fewest pesticides with lowest concentrations were found in the small subwatershed associated with traditional agricultural production. Although the pesticides found in the soils at the three sites were generally similar they tended to be higher in the southern part of the Cholutecan watershed, followed by the central zone, with the lowest concentrations being found in the more traditional production zone. In lagoon and well water samples more pesticides, but mostly in lower concentrations were detected at the traditional production site than at the others. Ten pesticide compounds were detected in fish tissue, mainly organochlorines, some of which were also found in lagoon sediments. In terms of food products, almost no pesticides were detected in vegetables, but the kidney adipose tissue taken from slaughtered cows was shown to have a tendency to contain some organochlorines. Spring water in the traditional agricultural production zone contained three organochlorine compounds

Removal of copper from acid wastewater of bioleaching by adsorption onto ramie residue and uptake by Trichoderma viride.

Science.gov (United States)

Wang, Buyun; Wang, Kai

2013-05-01

A continuous batch bioleaching was built to realize the bioleaching of sewage sludge in large scale. In the treatment, heavy metal in acid wastewater of bioleaching was removed by adsorption onto ramie residue. Then, acid wastewater was reused in next bioleaching batch. In this way, most time and water of bioleaching was saved and leaching efficiency of copper, lead and chromium kept at a high level in continuous batch bioleaching. It was found that residual heavy metal in sewage sludge is highly related to that in acid wastewater after bioleaching. To get a high leaching efficiency, concentration of heavy metal in acid wastewater should be low. Adsorption of copper from acid wastewater onto ramie residue can be described by pseudo first-order kinetics equation and Freundlich isotherm model. Trichoderma viride has the potential to be used for the concentration and recovery of heavy metal adsorbed onto ramie residue. Copyright © 2013 Elsevier Ltd. All rights reserved.

Heat transfer properties of organic coolants containing high boiling residues

International Nuclear Information System (INIS)

Debbage, A.G.; Driver, M.; Waller, P.R.

1964-01-01

Heat transfer measurements were made in forced convection with Santowax R, mixtures of Santowax R and pyrolytic high boiling residue, mixtures of Santowax R and CMRE Radiolytic high boiling residue, and OMRE coolant, in the range of Reynolds number 10 4 to 10 5 . The data was correlated with the equation Nu = 0.015 Re b 0.85 Pr b 0.4 with an r.m.s. error of ± 8.5%. The total maximum error arising from the experimental method and inherent errors in the physical property data has been estimated to be less than ± 8.5%. From the correlation and physical property data, the decrease in heat transfer coefficient with increasing high boiling residue concentration has been determined. It has been shown that subcooled boiling in organic coolants containing high boiling residues is a complex phenomenon and the advantages to be gained by operating a reactor in this region may be marginal. Gas bearing pumps used initially in these experiments were found to be unsuitable; a re-designed ball bearing system lubricated with a terphenyl mixture was found to operate successfully. (author)

Enhanced biogas production from penicillin bacterial residue by thermal-alkaline pretreatment

International Nuclear Information System (INIS)

Zhong, Weizhang; Li, Guixia; Gao, Yan; Li, Zaixing; Geng, Xiaoling; Li, Yubing; Yang, Jingliang; Zhou, Chonghui

2015-01-01

In this study, the orthogonal experimental design was used to determine the optimum conditions for the effect of thermal alkaline; pretreatment on the anaerobic digestion of penicillin bacterial residue. The biodegradability of the penicillin; bacterial residue was evaluated by biochemical methane potential tests in laboratory. The optimum values of temperature,; alkali concentration, pretreatment time and moisture content for the thermal-alkaline pretreatment were determined as; 70 °C, 6% (w/v), 30 min, and 85%, respectively. Thermal-alkaline pretreatment could significantly enhance the soluble; chemical oxygen demand solubilization, the suspended solid solubilization and the biodegradability. Biogas production; was enhanced by the thermal-alkaline pretreatment, probably as a result of the breakdown of cell walls and membranes of; micro-organisms, which may facilitate the contact between organic molecules and anaerobic microorganisms.; Keywords: penicillin bacterial residue; anaerobic digestion; biochemical methane potential tests; pretreatment

Factors affecting ANKOM™ fiber analysis of forage and browse varying in condensed tannin concentration.

Science.gov (United States)

Terrill, Thomas H; Wolfe, Richard M; Muir, James P

2010-12-01

Browse species containing condensed tannins (CTs) are an important source of nutrition for grazing/browsing livestock and wildlife in many parts of the world, but information on fiber concentration and CT-fiber interactions for these plants is lacking. Ten forage or browse species with a range of CT concentrations were oven dried and freeze dried and then analyzed for ash-corrected neutral detergent fiber (NDFom) and corrected acid detergent fiber (ADFom) using separate samples (ADFSEP) and sequential NDF-ADF analysis (ADFSEQ) with the ANKOM™ fiber analysis system. The ADFSEP and ADFSEQ residues were then analyzed for nitrogen (N) concentration. Oven drying increased (P < 0.05) fiber concentrations with some species, but not with others. For high-CT forage and browse species, ADFSEP concentrations were greater (P < 0.05) than NDFom values and approximately double the ADFSEQ values. Nitrogen concentration was greater (P < 0.05) in ADFSEP than ADFSEQ residues, likely due to precipitation with CTs. Sequential NDF-ADF analysis gave more realistic values and appeared to remove most of the fiber residue contaminants in CT forage samples. Freeze drying samples with sequential NDF-ADF analysis is recommended in the ANKOM™ fiber analysis system with CT-containing forage and browse species. Copyright © 2010 Society of Chemical Industry.

Susceptibilidad de Aedes aegypti a DDT, deltametrina y lambdacialotrina en Colombia Susceptibility of Aedes aegypti to DDT, deltamethrin, and lambda-cyhalothrin in Colombia

Directory of Open Access Journals (Sweden)

Liliana Santacoloma Varón

2010-01-01

Full Text Available OBJETIVOS: Evaluar el estado de susceptibilidad a insecticidas piretroides deltametrina y lambdacialotrina y al organoclorado DDT, e identificar los mecanismos bioquímicos asociados con resistencia en 13 poblaciones naturales de Aedes aegypti recolectadas en localidades de Colombia donde el dengue es un grave problema de salud pública. MÉTODOS: Se recolectaron y criaron en condiciones controladas formas inmaduras de diferentes criaderos naturales del vector para cada localidad. Con la generación F2 se realizaron bioensayos utilizando las metodologías OMS 1981 (papeles impregnados y CDC 1998 (botellas impregnadas. En las poblaciones con mortalidades compatibles con disminución de la susceptibilidad, se midieron los niveles de esterasas no específicas (ENE, oxidasas de función mixta (OFM y acetilcolinesterasa modificada (ACEM mediante pruebas colorimétricas. RESULTADOS: Todas las poblaciones del mosquito evaluadas evidenciaron resistencia al organoclorado DDT. En cuanto a los piretroides, se encontró resistencia generalizada a lambdacialotrina pero no a deltametrina. Los mecanismos bioquímicos de resistencia evaluados permitieron encontrar 7 de 11 poblaciones con ENE elevadas y una población con OFM incrementadas. CONCLUSIONES: Se descarta la resistencia cruzada de tipo fisiológico entre el DDT y lambdacialotrina en las poblaciones de A. aegypti evaluadas. La resistencia fisiológica a lambdacialotrina parece asociarse con el incremento de las ENE. El comportamiento diferencial en los niveles de susceptibilidad y los valores enzimáticos entre poblaciones se asociaron con la variabilidad genética y presión de selección química a nivel local.OBJECTIVES: To assess the susceptibility status of 13 natural populations of Aedes aegypti (collected from sites in Colombia where dengue is a serious public health problem to the pyrethroids, deltamethrin and lambda-cyhalothrin, and to the organochlorine, DDT, and to identify any biochemical

Determination of Profenofos Pesticidal Residue in Lettuce (Lactuca sativa L. by Gas Chromatographic Method

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Yohannes Alen

2015-05-01

Full Text Available The determination of profenofos pesticidal residue in the lettuce (Lactuca sativa L. by using gas chromatography using flame photometric detector (FPD had been investigated. The lettuce was collected from Padang Luar area, Agam distric, West Sumatera. Sample for determination of profenofos residue divided into three groups: unwashed (A, washed with water (B, and washed with detergent (C. Maceration with sonication was used for the extraction using ethylacetateas a solvent. The results showed that profenofos pesticide residue in sample A, B and C were 0.204, 0.080 and 0.061 ppm, respectively. These profenofos pesticidal residue are over than the Maximum Residue Limits (MRL that established by The Japan Food Chemical Research Foundation (0.05 ppm even though World Health Organization (WHO has not established Maximum Residue Limits (MRL profenofos on lettuce. Based on the statistical analysis one-way method (Anova using SPSS 20.0 showed that there was a significant concentrations difference between lettuce A from lettuce B and lettuce C with p < 0.05.

Enhanced Ethanol Production with Mixed Lignocellulosic Substrates from Commercial Furfural and Cassava Residues

Directory of Open Access Journals (Sweden)

Li Ji

2015-01-01

Full Text Available Simultaneous saccharification and fermentation (SSF is an attractive process configuration for bio-ethanol production. Further reductions in process cost of SSF are expected with the use of waste agricultural or industrial materials as feedstock. In the current study, two industrial lignocellulosic wastes, cassava residues (CR and furfural residues (FR, were combined during SSF for ethanol production due to their value-added applications and positive environmental impacts. After CR were liquefied and saccharified, saccharification liquid was added to SSF of FR. The effect of substrate fractions was investigated in terms of ethanol yield, byproduct concentration and the number of yeast cells. Besides, a natural surfactant, Gleditsia saponin, was added to investigate the effect of FR lignin on SSF with 20% substrate concentration. The results showed that increasing the ratio of CR/FR improved the ethanol yield and that the ethanol yield was also increased gradually by increasing the substrate concentration from 6% to 12%. A high ethanol concentration of 36.0 g/L was obtained under the condition of CR:FR = 2:1 with 12% substrate concentration, reaching 71.1% of the theoretical yield. However, Gleditsia saponin did not affect the ethanol yield, indicating the insignificant effect of lignin in SSF with low lignin content in the reaction system.

Estimation of selected residual antibiotics in muscle, kidney, liver, and egg of layer chicken

International Nuclear Information System (INIS)

Amjad, H.; Iqbal, J.; Naeem, M.

2006-01-01

The present studies were conducted for the estimation of quinolone residues in our local poultry products. The poultry products included muscle, kidney, liver and egg (yolk and white). The quinolones included in this study were, oxolonic acid, flumequine, enrofloxacin, and ciprofloxacin. An assessment of the variation of each analyte (quinolones antibiotic residues) in these products was made. A comparison was made among the analyte (quinolones) concentrations in different tissues/organs and their internationally permissible safer maximum residue limits (MRLS'). Infra Red spectra were used to detect the presence and identification of different quinolones. HPLC with ODS Column and U.V. detector was used for the quantification. (author)

Biochar from different residues on soil properties and common bean production

Directory of Open Access Journals (Sweden)

Isley Cristiellem Bicalho da Silva

Full Text Available ABSTRACT: The production of biochar from organic residues promises to be an interesting strategy for the management of organic waste. To assess the effect of biochar on soil properties and the production and nutrition of common bean (Phaseolus vulgaris L., three simultaneous experiments were conducted in a greenhouse with different biochar from organic residues (rice husk, sawdust, and sorghum silage used as filtration material for swine biofertilizer. In each experiment the treatments consisted of five different biochar concentrations (0, 25, 50, 75 and 100 L m−3, arranged in a completely randomized design, with four repetitions. In the experiments, the use of biochar increased soil pH, cation exchange capacity, nutrient availability in the soil, and nutrient accumulation in grains. The biochar concentrations corresponding to the maximum production of grain dry matter of bean plants were 100, 68, and 71 L m−3 for biochar from rice husk filter (BRHF, biochar from sawdust filter (BSF, and biochar from sorghum silage filter (BSSF, respectively.

Management of parthenium weed by extracts and residue of wheat ...

African Journals Online (AJOL)

This study was carried out to investigate the prospects of using methanolic extracts and residue of wheat (Triticum aestivum L.) for the management of parthenium (Parthenium hysterophorus L.), one of the world's worst weeds. In a laboratory bioassay, the effect of methanol extracts of 1, 2, 3, 4 and 5% (w/v) concentrations of ...

Rigid Residue Scan Simulations Systematically Reveal Residue Entropic Roles in Protein Allostery.

Directory of Open Access Journals (Sweden)

Robert Kalescky

2016-04-01

Full Text Available Intra-protein information is transmitted over distances via allosteric processes. This ubiquitous protein process allows for protein function changes due to ligand binding events. Understanding protein allostery is essential to understanding protein functions. In this study, allostery in the second PDZ domain (PDZ2 in the human PTP1E protein is examined as model system to advance a recently developed rigid residue scan method combining with configurational entropy calculation and principal component analysis. The contributions from individual residues to whole-protein dynamics and allostery were systematically assessed via rigid body simulations of both unbound and ligand-bound states of the protein. The entropic contributions of individual residues to whole-protein dynamics were evaluated based on covariance-based correlation analysis of all simulations. The changes of overall protein entropy when individual residues being held rigid support that the rigidity/flexibility equilibrium in protein structure is governed by the La Châtelier's principle of chemical equilibrium. Key residues of PDZ2 allostery were identified with good agreement with NMR studies of the same protein bound to the same peptide. On the other hand, the change of entropic contribution from each residue upon perturbation revealed intrinsic differences among all the residues. The quasi-harmonic and principal component analyses of simulations without rigid residue perturbation showed a coherent allosteric mode from unbound and bound states, respectively. The projection of simulations with rigid residue perturbation onto coherent allosteric modes demonstrated the intrinsic shifting of ensemble distributions supporting the population-shift theory of protein allostery. Overall, the study presented here provides a robust and systematic approach to estimate the contribution of individual residue internal motion to overall protein dynamics and allostery.

Detection of pesticides residues in water samples from organic and conventional paddy fields of Ledang, Johor, Malaysia

Science.gov (United States)

Abdullah, Md Pauzi; Othman, Mohamed Rozali; Ishak, Anizan; Nabhan, Khitam Jaber

2016-11-01

Pesticides have been used extensively by the farmers in Malaysia during the last few decades. Sixteen water samples, collected from paddy fields both organic and conventional, from Ledang, Johor, were analyzed to determine the occurrence and distribution of organochlorine (OCPs) and organophosphorus (OPPs) pesticide residues. GC-ECD instrument was used to identify and determine the concentrations of these pesticide residues. Pesticide residues were detected in conventional fields in the range about 0.036-0.508 µg/L higher than detected in organic fields about 0.015-0.428 µg/L. However the level of concentration of pesticide residues in water sample from both paddy fields are in the exceed limit for human consumption, according to European Economic Commission (EEC) (Directive 98/83/EC) at 0.1 µg/L for any pesticide or 0.5 µg/L for total pesticides. The results that the organic plot is still contaminated with pesticides although pesticides were not use at all in plot possibly from historical used as well as from airborne contamination.

Instrumental neutron activation analysis of coal and its combustion residues from a power plant

International Nuclear Information System (INIS)

Lim, J.M.; Jeong, J.H.; Lee, J.H.

2013-01-01

A growing demand of electrical energy derived from coal combustion led to a significant increase of coal ash as residues. Approximately 70 % of the fly ashes are recycled, while most of the bottom ashes have been land-filled in the ash pond in Korea. In this work, to evaluate the potential impacts of the residues from a coal power plant on the environment, its inorganic elemental components were determined by INAA and PGAA. Coal ash samples were collected from the biggest power plant complex in Korea. These samples were analyzed by using the NAA facilities in the HANARO research reactor of the Korea Atomic Energy Research Institute. A total of 31 elements were analyzed in the samples, and certified reference materials were used for the analytical quality control. The enrichment status of a given metal in fuel coal and ashes was investigated by its concentration ratio. In order to assess the impact of the coal combustion residues on ecosystem, their concentrations determined for each respective type of the samples were compared to both reference data and nearby beach sand samples. (author)

Investigation of the source of residual phthalate in sundried salt.

Science.gov (United States)

Kim, Jin Hyo; Lee, Jin Hwan; Kim, So-Young

2014-03-01

Phthalate contamination in sundried salt has recently garnered interest in Korea. Phthalate concentrations were investigated in Korean sundried salts, source waters, and aqueous extracts from polyvinyl chloride materials used in salt ponds. Preliminary screening results for phthalates in Korean sundried salts revealed that only di(2-ethylhexyl)phthalate (DEHP) was over the limit of detection, with an 8.6% detection rate, and the concentration ranged from below the limit of detection to 0.189 mg/kg. The tolerable daily intake contribution ratio of the salt was calculated to be only 0.001%. Residual phthalates were below 0.026 mg/liter in source water, and the aqueous extracted di-n-butylphthalate, benzylbutylphthalate, and DEHP, which are considered endocrine disruptors, were below 0.029 mg/kg as derived from the polyvinyl chloride materials in salt ponds. The transfer ratios of the six phthalates from seawater to sundried salts were investigated; transfer ratio was correlated with vapor pressure (r(2) = 0.9875). Thus, di-n-butylphthalate, benzylbutylphthalate, DEHP, and di-n-octylphthalate can be considered highly likely residual pollutants in some consumer salts.

MODELLING DICLOFENAC AND IBUPROFEN RESIDUES IN MAJOR ESTONIAN SEASIDE CITIES

Directory of Open Access Journals (Sweden)

Erki Lember

2016-06-01

Full Text Available A theoretical model was developed to model the fate of two common pharmaceutical residues: diclofenac and ibuprofen in eight Estonian seaside cities that discharge their wastewaters directly into the Baltic Sea. The consumption rates of the active ingredients of diclofenac and ibuprofen from 2006-2014 were analysed. A decrease of 19.9% for diclofenac consumption and an increase of 14.1% for ibuprofen were found. The fate of diclofenac and ibuprofen were modelled by considering the human metabolism removal rate for pharmaceuticals, the removal rate of diclofenac and ibuprofen in activated sludge wastewater treatment plants (WWTP and annual flow rates. An average decrease from 1 to 0.8 µg/l (decrease of 20% for diclofenac and an increase from 11.4 to 13.4 µg/l (increase of 14.9% for ibuprofen for the concentration in the effluents of the WWTP were modelled. The model gives us a good overview about the theoretical concentrations of pharmaceutical residues in the environment and is helpful for evaluating environmental impacts.

Factors influencing liver PCB concentrations in sparrowhawks (Accipiter nisus), kestrels (Falco tinnunculus) and herons (Ardea cinerea) in Britain

Energy Technology Data Exchange (ETDEWEB)

Wienburg, Claire L.; Shore, Richard F

2004-11-01

Large scale temporal and spatial changes in the exposure of terrestrial vertebrates to PCBs have been monitored in the UK by measuring liver residues in sparrowhawks (Accipiter nisus), kestrels (Falco tinnunculus) and grey herons (Ardea cinerea) from throughout the country. Residues in the three species are typically characterised by large intra- and inter-specific variation. Data for 306 sparrowhawks, 186 kestrels and 47 herons collected between 1992 and 1997 as part of a national Predatory Bird Monitoring Scheme were examined to determine how much of this variation was explained by body condition, age and sex, rather than other factors. In all three species, body condition was the single most important factor and accounted for up to 49% of the variation in PCB liver residues; starved birds had the highest liver concentrations. Age and sex were also significant but of lesser importance. Adult sparrowhawks and kestrels had liver PCB residues that were 2 to 10-fold higher than in first-year birds. Sex did not affect residue magnitude in a consistent manner. PCB concentrations in the liver were higher in males than females in both first-year and adult kestrels and in first-year sparrowhawks, but adult female sparrowhawks had similar PCB residues to adult males. Liver residues also varied seasonally. PCB concentrations in first-year sparrowhawks increased during the first year following fledging and a similar pattern was detected in adult female sparrowhawks following egg laying. When these physiological factors were taken into account, it was evident that while kestrels with high fat scores had significantly lower PCB concentrations than either sparrowhawks or herons, liver residues were similar in all three species when birds were in a starved condition. Overall during 1992-1997, the combined influence of body condition, age and sex explained more of the variation in liver PCB concentrations than species differences or other factors, such as geographical variation

Residual stress behaviors induced by laser peening along the edge of curved models

International Nuclear Information System (INIS)

Im, Jong Bin; Grandhi, Ramana V.; Ro, Young Hee

2012-01-01

Laser peening (LP) induces high magnitude compressive residual stresses in a small region of a component. The compressive residual stresses cause plastic deformation that is resistant to fatigue fracture. Fatigue cracks are generally nucleated at critical areas, and LP is applied for those regions so as to delay the crack initiation. Many critical regions are located on the edge of the curved portion of structures because of stress concentration effects. Several investigations that are available for straight components may not give meaningful guidelines for peening curved components. Therefore, in this paper, we investigate residual stress behaviors induced by LP along the edge of curved models. Three curved models that have different curvatures are investigated for peening performance. Two types of peening configurations, which are simultaneous corner shot and sequential corner shots, are considered in order to obtain compressive residual stresses along an edge. LP simulations of multiple shots are performed to identify overlapping effects on the edge portion of a curved model. In addition, the uncertainty calculation of residual stress induced by LP considering laser pulse duration is performed

Comparison of residual stress measurement in thin films using surface micromachining method

International Nuclear Information System (INIS)

He, Q.; Luo, Z.X.; Chen, X.Y.

2008-01-01

Conductive, dielectric, semiconducting, piezoelectric and ferroelectric thin films are extensively used for MEMS/NEMS applications. One of the important parameters of thin films is residual stress. The residual stress can seriously affect the properties, performance and long-term stability of the films. Excessive compressive or tensile stress results in buckling, cracking, splintering and sticking problems. Stress measurement techniques are therefore essential for both process development and process monitoring. Many suggestions for stress measurement in thin films have been made over the past several decades. This paper is concentrated on the in situ stress measurement using surface micromachining techniques to determine the residual stress. The authors review and compare several types of stress measurement methods including buckling technique, rotating technique, micro strain gauge and long-short beam strain sensor

Elemental quantification of large gunshot residues

Energy Technology Data Exchange (ETDEWEB)

Duarte, A. [Ion Implantation Laboratory, Institute of Physics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, P.O. Box 15051, CEP 91501-970 Porto Alegre, RS (Brazil); Graduate Program on Materials Science, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, CEP 91540-000 Porto Alegre, RS (Brazil); Silva, L.M. [Ion Implantation Laboratory, Institute of Physics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, P.O. Box 15051, CEP 91501-970 Porto Alegre, RS (Brazil); Graduate Program on Materials Science, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, CEP 91540-000 Porto Alegre, RS (Brazil); Forensic Institute of Porto Alegre, Av. Princesa Isabel 1056, CEP 90230-010 Porto Alegre, RS (Brazil); Souza, C.T. de; Stori, E.M. [Ion Implantation Laboratory, Institute of Physics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, P.O. Box 15051, CEP 91501-970 Porto Alegre, RS (Brazil); Boufleur, L.A. [Ion Implantation Laboratory, Institute of Physics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, P.O. Box 15051, CEP 91501-970 Porto Alegre, RS (Brazil); Graduate Program on Materials Science, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, CEP 91540-000 Porto Alegre, RS (Brazil); Amaral, L. [Ion Implantation Laboratory, Institute of Physics, Federal University of Rio Grande do Sul, Av. Bento Gonçalves 9500, P.O. Box 15051, CEP 91501-970 Porto Alegre, RS (Brazil); and others

2015-04-01

In the present work we embarked on the evaluation of the Sb/Pb, Ba/Pb and Sb/Ba elemental ratios found in relatively large particles (of the order of 50–150 μm across) ejected in the forward direction when a gun is fired. These particles are commonly referred to as gunshot residues (GSR). The aim of this work is to compare the elemental ratios of the GSR with those found in the primer of pristine cartridges in order to check for possible correlations. To that end, the elemental concentration of gunshot residues and the respective ammunition were investigated through PIXE (Particle-Induced X-ray Emission) and micro-PIXE techniques. The ammunition consisted of a .38 SPL caliber (ogival lead type) charged in a Taurus revolver. Pristine cartridges were taken apart for the PIXE measurements. The shooting sessions were carried out in a restricted area at the Forensic Institute at Porto Alegre. Residues ejected at forward directions were collected on a microporous tape. The PIXE experiments were carried out employing 2.0 MeV proton beams with a beam spot size of 1 mm{sup 2}. For the micro-PIXE experiments, the samples were irradiated with 2.2 MeV proton beams of 2 × 2 μm{sup 2}. The results found for the ratios of Sb/Pb, Ba/Pb and Sb/Ba do not correlate with those stemming from the analysis of the primer.

Elemental quantification of large gunshot residues

International Nuclear Information System (INIS)

Duarte, A.; Silva, L.M.; Souza, C.T. de; Stori, E.M.; Boufleur, L.A.; Amaral, L.

2015-01-01

In the present work we embarked on the evaluation of the Sb/Pb, Ba/Pb and Sb/Ba elemental ratios found in relatively large particles (of the order of 50–150 μm across) ejected in the forward direction when a gun is fired. These particles are commonly referred to as gunshot residues (GSR). The aim of this work is to compare the elemental ratios of the GSR with those found in the primer of pristine cartridges in order to check for possible correlations. To that end, the elemental concentration of gunshot residues and the respective ammunition were investigated through PIXE (Particle-Induced X-ray Emission) and micro-PIXE techniques. The ammunition consisted of a .38 SPL caliber (ogival lead type) charged in a Taurus revolver. Pristine cartridges were taken apart for the PIXE measurements. The shooting sessions were carried out in a restricted area at the Forensic Institute at Porto Alegre. Residues ejected at forward directions were collected on a microporous tape. The PIXE experiments were carried out employing 2.0 MeV proton beams with a beam spot size of 1 mm 2 . For the micro-PIXE experiments, the samples were irradiated with 2.2 MeV proton beams of 2 × 2 μm 2 . The results found for the ratios of Sb/Pb, Ba/Pb and Sb/Ba do not correlate with those stemming from the analysis of the primer

Insecticide resistance status of three malaria vectors, Anopheles gambiae (s.l.), An. funestus and An. mascarensis, from the south, central and east coasts of Madagascar.

Science.gov (United States)

Rakotoson, Jean-Desire; Fornadel, Christen M; Belemvire, Allison; Norris, Laura C; George, Kristen; Caranci, Angela; Lucas, Bradford; Dengela, Dereje

2017-08-23

Insecticide-based vector control, which comprises use of insecticide-treated bed nets (ITNs) and indoor residual spraying (IRS), is the key method to malaria control in Madagascar. However, its effectiveness is threatened as vectors become resistant to insecticides. This study investigated the resistance status of malaria vectors in Madagascar to various insecticides recommended for use in ITNs and/or IRS. WHO tube and CDC bottle bioassays were performed on populations of Anopheles gambiae (s.l.), An. funestus and An. mascarensis. Adult female An. gambiae (s.l.) mosquitoes reared from field-collected larvae and pupae were tested for their resistance to DDT, permethrin, deltamethrin, alpha-cypermethrin, lambda-cyhalothrin, bendiocarb and pirimiphos-methyl. Resting An. funestus and An. mascarensis female mosquitoes collected from unsprayed surfaces were tested against permethrin, deltamethrin and pirimiphos-methyl. The effect on insecticide resistance of pre-exposure to the synergists piperonyl-butoxide (PBO) and S,S,S-tributyl phosphorotrithioate (DEF) also was assessed. Molecular analyses were done to identify species and determine the presence of knock-down resistance (kdr) and acetylcholinesterase resistance (ace-1 R ) gene mutations. Anopheles funestus and An. mascarensis were fully susceptible to permethrin, deltamethrin and pirimiphos-methyl. Anopheles gambiae (s.l.) was fully susceptible to bendiocarb and pirimiphos-methyl. Among the 17 An. gambiae (s.l.) populations tested for deltamethrin, no confirmed resistance was recorded, but suspected resistance was observed in two sites. Anopheles gambiae (s.l.) was resistant to permethrin in four out of 18 sites (mortality 68-89%) and to alpha-cypermethrin (89% mortality) and lambda-cyhalothrin (80% and 85%) in one of 17 sites, using one or both assay methods. Pre-exposure to PBO restored full susceptibility to all pyrethroids tested except in one site where only partial restoration to permethrin was observed. DEF

Syntetiske pyrethroider i private hjem

DEFF Research Database (Denmark)

Jensen, Karl-Martin Vagn; Fomsgaard, Inge S.; Kilpinen, Ole Østerlund

2015-01-01

A number of different methods are tested to elucidate the accumulation of synthetic pyrethroids in private homes. When the target pest is resistant, there is a potential risk that persistent synthetic pyrethroids accumulate because of repeated treatments. The highest residue found was 8260 µg lam...... lambda-cyhalothrin in a vacuum-cleaner sample (vacuumed for 10 minutes) and 1252 µg lambda-cyhalothrin in a “cotton sock dosimeter” sample. Similar data for deltamethrin was 805 µg in a vacuum-cleaner sample and 806 µg in a “cotton sock dosimeter” sample....

Quantification of heavy metals from residual waste and ashes from the treatment plant of residual water Reciclagua and,effects for the health of those workers which manipulate those residuals; Cuantificacion de metales pesados de lodo residual y cenizas de la planta tratadora de aguas residuales Reciclagua y efectos a la salud de los trabajadores que manipulan los residuos

Energy Technology Data Exchange (ETDEWEB)

Guerrero D, J.J

2004-07-01

concentrations greater than 0.5% in weight, as long as the analysis of plasma emission spectroscopy very low concentrations are identified already that this method causes the destruction of the sample achieving the identification of all the present elements. With the obtained results we are able to compare the concentrations of the metals before and after the leaching and we calculate by this way the percentage of efficiency for each one of the variables that were managed in the development of the study, obtaining the extraction of those toxic, and valuable metals, present in the muds until of 100%. Based on the results we can mention that the workers are exposed to aerosols and powders of these toxic residuals which contain heavy metals. (Author)

[Scientific basis in the setting of residue limits for veterinary drugs in food of animal origin taking into account the presence of their metabolites].

Science.gov (United States)

Mitsumori, K

1993-01-01

Maximum residue level (MRL) for veterinary drugs in food of animal origin has been proposed by FAO/WHO, as a new evaluation procedure taking into account the presence of metabolites for the regulation of veterinary drug residues. The MRL is the maximum concentration of residue resulting from the use of a veterinary drug that is recommended to be legally permitted as acceptable in a food. It is established from the Acceptable Daily Intake (ADI) obtained from the data of toxicological studies, the residue concentration of the drug when used according to good practice in the use of veterinary drugs, and the lowest level consistent with the practical analytical methods available for routine residue analysis. Among the veterinary drugs, some chemicals contain a large amount of bound residues that are neither extractable from tissues by the analytical method identical with that used in parent chemicals. Especially, the bioavailable residues which are probably absorbed when the food is ingested are of great toxicological concern. In this case, the FAO/WHO recommends that the MRL can be established after the calculation of daily intake of residues of toxicological concern by the addition of both the extractable and bioavailable bound residues.

The use of biogas plant fermentation residue for the stabilisation of toxic metals in agricultural soils

Science.gov (United States)

Geršl, Milan; Šotnar, Martin; Mareček, Jan; Vítěz, Tomáš; Koutný, Tomáš; Kleinová, Jana

2015-04-01

Our department has been paying attention to different methods of soil decontamination, including the in situ stabilisation. Possible reagents to control the toxic metals mobility in soils include a fermentation residue (FR) from a biogas plant. Referred to as digestate, it is a product of anaerobic decomposition taking place in such facilities. The fermentation residue is applied to soils as a fertiliser. A new way of its use is the in situ stabilisation of toxic metals in soils. Testing the stabilisation of toxic metals made use of real soil samples sourced from five agriculturally used areas of the Czech Republic with 3 soil samples taken from sites contaminated with Cu, Pb and Zn and 2 samples collected at sites of natural occurrence of Cu, Pb and Zn ores. All the samples were analysed using the sequential extraction procedure (BCR) (determine the type of Cu, Pb and Zn bonds). Stabilisation of toxic metals was tested in five soil samples by adding reagents as follows: dolomite, slaked lime, goethite, compost and fermentation residue. A single reagent was added at three different concentrations. In the wet state with the added reagents, the samples were left for seven days, shaken twice per day. After seven days, metal extraction was carried out: samples of 10 g soil were shaken for 2 h in a solution of 0.1M NH4NO3 at a 1:2.5 (g.ml-1), centrifuged for 15 min at 5,000 rpm and then filtered through PTFE 0.45 μm mesh filters. The extracts were analysed by ICP-OES. Copper The best reduction of Cu concentration in the extract was obtained at each of the tested sites by adding dolomite (10 g soil + 0.3 g dolomite). The concentration of Cu in the leachate decreased to 2.1-18.4% compare with the leachate without addition. Similar results were also shown for the addition of fermentation residue (10 g soil + 1 g FR). The Cu concentration in the leachate decreased to 16.7-26.8% compared with the leachate without addition. Lead The best results were achieved by adding

The residues and environmental risks of multiple veterinary antibiotics in animal faeces.

Science.gov (United States)

Li, Yan-Xia; Zhang, Xue-Lian; Li, Wei; Lu, Xiao-Fei; Liu, Bei; Wang, Jing

2013-03-01

To understand the residues and ecological risks of veterinary antibiotics (VAs) in animal faeces from concentrated animal feeding operations in northeastern China, 14 VAs were identified by high performance liquid chromatography, and the preliminary risks of six antibiotics were assessed using the hazard quotient (HQ). The investigated VAs occurred in 7.41 to 57.41 % of the 54 samples, and the levels ranged from 0.08 to 56.81 mg kg(-1). Tetracyclines were predominant with a maximum level of 56.81 mg kg(-1) mostly detected in pig faeces. Sulfonamides were common and detected with the highest concentration of 7.11 mg kg(-1). Fluoroquinolones were more widely detected in chicken faeces rather than in pig or cow faeces, which contained the dominant antibiotic enrofloxacin. In comparison, the residue of tylosin was less frequently found. The risk evaluations of the six antibiotics revealed that tetracyclines, especially oxytetracycline, displayed the greatest ecological risk because of its high HQ value of 15.75. The results of this study imply that multiple kinds of VAs were jointly used in animal feeding processes in the study area. These medicine residues in animal faeces may potentially bring ecological risks if the animal manure is not treated effectively.

Residual gas analysis

International Nuclear Information System (INIS)

Berecz, I.

1982-01-01

Determination of the residual gas composition in vacuum systems by a special mass spectrometric method was presented. The quadrupole mass spectrometer (QMS) and its application in thin film technology was discussed. Results, partial pressure versus time curves as well as the line spectra of the residual gases in case of the vaporization of a Ti-Pd-Au alloy were demonstrated together with the possible construction schemes of QMS residual gas analysers. (Sz.J.)

Assessing the Availability of Wood Residues and Residue Markets in Virginia

OpenAIRE

Alderman, Delton R. Jr.

1998-01-01

A statewide mail survey of primary and secondary wood product manufacturers was undertaken to quantify the production and consumption of wood residues in Virginia. Two hundred and sixty-six wood product manufacturers responded to the study and they provided information on the production, consumption, markets, income or disposal costs, and disposal methods of wood residues. Hardwood and pine sawmills produce approximately 66 percent of Virginia's wood residues. Virginia's wood product man...

Hydride vapor phase GaN films with reduced density of residual electrons and deep traps

International Nuclear Information System (INIS)

Polyakov, A. Y.; Smirnov, N. B.; Govorkov, A. V.; Yugova, T. G.; Cox, H.; Helava, H.; Makarov, Yu.; Usikov, A. S.

2014-01-01

Electrical properties and deep electron and hole traps spectra are compared for undoped n-GaN films grown by hydride vapor phase epitaxy (HVPE) in the regular process (standard HVPE samples) and in HVPE process optimized for decreasing the concentration of residual donor impurities (improved HVPE samples). It is shown that the residual donor density can be reduced by optimization from ∼10 17  cm −3 to (2–5) × 10 14  cm −3 . The density of deep hole traps and deep electron traps decreases with decreased donor density, so that the concentration of deep hole traps in the improved samples is reduced to ∼5 × 10 13  cm −3 versus 2.9 × 10 16  cm −3 in the standard samples, with a similar decrease in the electron traps concentration

Phytotoxicity and groundwater impacts of leaching from thermal treatment residues in roadways.

Science.gov (United States)

Phoungthong, Khamphe; Shao, Li-Ming; He, Pin-Jing; Zhang, Hua

2018-01-01

The use of coal fly ash (CFA), municipal solid waste incinerator bottom ash (MSWIBA) and flue gas desulfurization residue (FGDR) in road construction has become very common owing to its economical advantages. However, these residues may contain toxic constituents that pose an environmental risk if they leach out and flow through the soil, surface water and groundwater. Therefore, it is necessary to assess the ecotoxicity and groundwater impact of these residues before decisions can be made regarding their utilization for road construction. In this study, the physico-chemical characteristics, leaching and phytotoxicity of these residues were investigated. Specifically, multivariate analyses were used to evaluate the contributions of the leaching constituents of the CFA, MSWIBA and FGDR leachates to the germination index of wheat seeds. B, Ba, Cr, Cu, Fe and Pb were found to be more toxic to the wheat seeds than the other heavy metals. Furthermore, the leached concentrations of the constituents from the CFA, MSWIBA and FGDR were below the regulatory threshold limits of the Chinese identification standard for hazardous wastes. Analyses conducted using a numerical groundwater model (WiscLEACH) indicated that the predicted field concentrations of metals from the CFA, MSWIBA and FGDR increased with time up to about 30years at the point of compliance, then decreased with time and distance. Overall, this study demonstrated that the risks resulting from MSWIBA, CFA and FGDR leaching could be assessed before its utilization for road construction, providing crucial information for the adoption of these alternative materials. Copyright © 2016. Published by Elsevier B.V.

Assessing potential forest and steel inter-industry residue utilisation by sequential chemical extraction

Energy Technology Data Exchange (ETDEWEB)

Makela, M.

2012-10-15

Traditional process industries in Finland and abroad are facing an emerging waste disposal problem due recent regulatory development which has increased the costs of landfill disposal and difficulty in acquiring new sites. For large manufacturers, such as the forest and ferrous metals industries, symbiotic cooperation of formerly separate industrial sectors could enable the utilisation waste-labeled residues in manufacturing novel residue-derived materials suitable for replacing commercial virgin alternatives. Such efforts would allow transforming the current linear resource use and disposal models to more cyclical ones and thus attain savings in valuable materials and energy resources. The work described in this thesis was aimed at utilising forest and carbon steel industry residues in the experimental manufacture of novel residue-derived materials technically and environmentally suitable for amending agricultural or forest soil properties. Single and sequential chemical extractions were used to compare the pseudo-total concentrations of trace elements in the manufactured amendment samples to relevant Finnish statutory limit values for the use of fertilizer products and to assess respective potential availability under natural conditions. In addition, the quality of analytical work and the suitability of sequential extraction in the analysis of an industrial solid sample were respectively evaluated through the analysis of a certified reference material and by X-ray diffraction of parallel sequential extraction residues. According to the acquired data, the incorporation of both forest and steel industry residues, such as fly ashes, lime wastes, green liquor dregs, sludges and slags, led to amendment liming capacities (34.9-38.3%, Ca equiv., d.w.) comparable to relevant commercial alternatives. Only the first experimental samples showed increased concentrations of pseudo-total cadmium and chromium, of which the latter was specified as the trivalent Cr(III). Based on

Effect of paste processing on residue levels of imidacloprid, pyraclostrobin, azoxystrobin and fipronil in winter jujube.

Science.gov (United States)

Peng, Wei; Zhao, Liuwei; Liu, Fengmao; Xue, Jiaying; Li, Huichen; Shi, Kaiwei

2014-01-01

The changes of imidacloprid, pyraclostrobin, azoxystrobin and fipronil residues were studied to investigate the carryover of pesticide residues in winter jujube during paste processing. A multi-residue analytical method for winter jujube was developed based on the QuEChERS approach. The recoveries for the pesticides were between 87.5% and 116.2%. LODs ranged from 0.002 to 0.1 mg kg(-1). The processing factor (Pf) is defined as the ratio of pesticide residue concentration in the paste to that in winter jujube. Pf was higher than 1 for the removal of extra water, and other steps were generally less than 1, indicating that the whole process resulted in lower pesticide residue levels in paste. Peeling would be the critical step for pesticide removal. Processing factors varied among different pesticides studied. The results are useful to address optimisation of the processing techniques in a manner that leads to considerable pesticide residue reduction.

Mapping residual stress by ultrasonic tomography

International Nuclear Information System (INIS)

Hildebrand, B.P.; Harrington, T.P.

1979-01-01

It is known that internal stress concentrations can give rise to microcracks which then grow when the structure is subjected to external forces. It has also been found that the velocity of sound is altered as it propagates through a region of stress. In this paper a technique called Computer-Assisted Tomography (CAT) is discussed and an application that provides pictures of stress fields is described. The results of both simulated and experimental models used to evaluate the technique are reported. It is concluded that the CAT approach has great potential for locating and mapping residual stress in metals. (author)

Elimination of super(14)C-bisazir residues in adult sea lamprey (Petromyzon marinus)

Science.gov (United States)

Allen, J.L.; Dawson, V.K.

1987-01-01

Bisazir (P.P-bis(1-aziridinyl)-N-methylphosphinothioic amide), a chemosterilant, was administered to sea lampreys (Petromyzon marinus ) by intraperitoneal injection of 100 mg/kg or by immersion for 2 h in a 100- mg/L aqueous solution of the chemical. Whole body analysis of the injected lampreys showed that total residue concentrations decreased to 4.65 in males and 10.07 in females during the first day after injection, and to 1.46 in males and 3.74 in females after 10 days of withdrawal. Lampreys exposed by bath immersion contained residues of about 25 mu g/g of tissue immediately after exposure. The concentration ( mu g/g) decreased to 1.02 in males and 2.11 in females after 1 day of withdrawal and to 0.51 in males and 0.85 in females after 10 days.

Residues and accumulation of molinate in rice crops and aquatic weeds in the MUDA rice agroecosystem

International Nuclear Information System (INIS)

Nashriyah Mat; Sabri Junoh; Nuriati Nurdin; Ramli Ishak

2002-01-01

Plant and soil residue levels and its accumulation in rice crops and rice aquatic weed plants were studied. Molinate residue levels in rice, weeds and soil were not significantly different between the recycled and the non-recycled area, even though they were higher in the non-recycled area. In the rice plant, the residue level at 10 DAT (days after treatment) was significantly higher than 30 DAT in the recycled area. In rice aquatic weed plants, the residue level was significantly higher at 10 DAT as compared to 30 DAT in the non-recycled area. Molinate residue levels in soil at 10 DAT and 30 DAT were similar. Molinate accumulated (ratio of molinate concentration in plant over soil) more in the rice crop as compared to rice aquatic weeds at 10 DAT, in both the recycled and the non-recycled areas. (Author)

Effectiveness of insecticide-incorporated bags to control stored-product beetles

Science.gov (United States)

Adults of seven stored-product beetle species were exposed on the inside and outside surfaces of polypropylene polymer bags incorporated with the insecticide deltamethrin (approx. concentration of 3,000 ppm; ZeroFly® Storage Bags (3g/kg). Beetles were exposed for 60, 120, and 180 min, and 1, 3 and 5...

Mutational properties of amino acid residues: implications for evolvability of phosphorylatable residues

DEFF Research Database (Denmark)

Creixell, Pau; Schoof, Erwin M.; Tan, Chris Soon Heng

2012-01-01

in terms of their mutational activity. Moreover, we highlight the importance of the genetic code and physico-chemical properties of the amino acid residues as likely causes of these inequalities and uncover serine as a mutational hot spot. Finally, we explore the consequences that these different......; it is typically assumed that all amino acid residues are equally likely to mutate or to result from a mutation. Here, by reconstructing ancestral sequences and computing mutational probabilities for all the amino acid residues, we refute this assumption and show extensive inequalities between different residues...... mutational properties have on phosphorylation site evolution, showing that a higher degree of evolvability exists for phosphorylated threonine and, to a lesser extent, serine in comparison with tyrosine residues. As exemplified by the suppression of serine's mutational activity in phosphorylation sites, our...

Impact of a proposed revision of the IESTI equation on the acute risk assessment conducted when setting maximum residue levels (MRLs) in the European Union (EU): A case study.

Science.gov (United States)

Breysse, Nicolas; Vial, Gaelle; Pattingre, Lauriane; Ossendorp, Bernadette C; Mahieu, Karin; Reich, Hermine; Rietveld, Anton; Sieke, Christian; van der Velde-Koerts, Trijntje; Sarda, Xavier

2018-06-03

Proposals to update the methodology for the international estimated short-term intake (IESTI) equations were made during an international workshop held in Geneva in 2015. Changes to several parameters of the current four IESTI equations (cases 1, 2a, 2b, and 3) were proposed. In this study, the overall impact of these proposed changes on estimates of short-term exposure was studied using the large portion data available in the European Food Safety Authority PRIMo model and the residue data submitted in the framework of the European Maximum Residue Levels (MRL) review under Article 12 of Regulation (EC) No 396/2005. Evaluation of consumer exposure using the current and proposed equations resulted in substantial differences in the exposure estimates; however, there were no significant changes regarding the number of accepted MRLs. For the different IESTI cases, the median ratio of the new versus the current equation is 1.1 for case 1, 1.4 for case 2a, 0.75 for case 2b, and 1 for case 3. The impact, expressed as a shift in the IESTI distribution profile, indicated that the 95th percentile IESTI shifted from 50% of the acute reference dose (ARfD) with the current equations to 65% of the ARfD with the proposed equations. This IESTI increase resulted in the loss of 1.2% of the MRLs (37 out of 3110) tested within this study. At the same time, the proposed equations would have allowed 0.4% of the MRLs (14 out of 3110) that were rejected with the current equations to be accepted. The commodity groups that were most impacted by these modifications are solanacea (e.g., potato, eggplant), lettuces, pulses (dry), leafy brassica (e.g., kale, Chinese cabbage), and pome fruits. The active substances that were most affected were fluazifop-p-butyl, deltamethrin, and lambda-cyhalothrin.

Biofiltration of composting gases using different municipal solid waste-pruning residue composts: monitoring by using an electronic nose.

Science.gov (United States)

López, R; Cabeza, I O; Giráldez, I; Díaz, M J

2011-09-01

The concentration of volatile organic compounds (VOCs) during the composting of kitchen waste and pruning residues, and the abatement of VOCs by different compost biofilters was studied. VOCs removal efficiencies greater than 90% were obtained using composts of municipal solid waste (MSW) or MSW-pruning residue as biofilter material. An electronic nose identified qualitative differences among the biofilter output gases at very low concentrations of VOCs. These differences were related to compost constituents, compost particle size (2-7 or 7-20mm), and a combination of both factors. The total concentration of VOCs determined by a photoionization analyser and inferred from electronic nose data sets were correlated over an ample range of concentrations of VOCs, showing that these techniques could be specially adapted for the monitoring of these processes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

Directory of Open Access Journals (Sweden)

Korrapati Kotinagu

2015-04-01

Full Text Available Aim: The present study was conducted to find the organochlorine pesticide (OCP and organophosphorus pesticide (OPP residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077. Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167. The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India.

Science.gov (United States)

Kotinagu, Korrapati; Krishnaiah, Nelapati

2015-04-01

The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

Simple detection of residual enrofloxacin in meat products using microparticles and biochips.

Science.gov (United States)

Ha, Mi-Sun; Chung, Myung-Sub; Bae, Dong-Ho

2016-05-01

A simple and sensitive method for detecting enrofloxacin, a major veterinary fluoroquinolone, was developed. Monoclonal antibody specific for enrofloxacin was immobilised on a chip and fluorescent dye-labelled microparticles were covalently bound to the enrofloxacin molecules. Enrofloxacin in solution competes with the microparticle-immobilised enrofloxacin (enroMPs) to bind to the antibody on the chip. The presence of enrofloxacin was verified by detecting the fluorescence of enrofloxacin-bound microparticles. Under optimum conditions, a high dynamic range was achieved at enrofloxacin concentrations ranging from 1 to 1000 μg kg(-1). The limits of detection and quantification for standard solutions were 5 and 20 μg kg(-1) respectively, which are markedly lower than the maximum residue limit. Using simple extraction methods, recoveries from fortified beef, pork and chicken samples were 43.4-62.3%. This novel method also enabled approximate quantification of enrofloxacin concentration: the enroMP signal intensity decreased with increasing enrofloxacin concentration. Because of its sensitivity, specificity, simplicity and rapidity, the method described herein will facilitate the detection and approximate quantification of enrofloxacin residues in foods in a high-throughput manner.

Effect of irradiation on erythromycin residues in poultry meat

International Nuclear Information System (INIS)

Mazurowski, P.

1993-01-01

Ionising radiation in doses used for radurisation (Recommendations of international organizations admit for poultry meat doses up to 5 kGy. Practically doses up to 3 kGy are applied does not influence erythromycin concentration in poultry meat. Doses on a level 10 kGy reduce its concentration in slurry more effectively, but results of earlier studies on penicillin and streptomycin suggest, that reduction of erythromycin level in meat should be smaller than in slurry. This allows an assumption that poultry meat irradiation with radurisation doses (up to 5 kGy), does not cause danger of overlooking of erythromycin residues in meat, with traditional, microbiological methods of detection. (orig.)

Residual stress evaluation and curvature behavior of aluminum 7050 peen forming processed; Avaliacao da tensao residual em aluminio 7050 conformado pelo processo peen forming

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Rene Ramos de

2011-07-01