Thrombotic microangiopathy associated with Valproic acid toxicity.

Science.gov (United States)

Hebert, Sean A; Bohan, Timothy P; Erikson, Christian L; Swinford, Rita D

2017-08-03

Thrombotic microangiopathy (TMA) is a serious, sometimes life-threatening disorder marked by the presence of endothelial injury and microvascular thrombi. Drug-induced thrombotic microangiopathy (DI-TMA) is one specific TMA syndrome that occurs following drug exposure via drug-dependent antibodies or direct tissue toxicity. Common examples include calcineurin inhibitors Tacrolimus and Cyclosporine and antineoplastics Gemcitabine and Mitomycin. Valproic acid has not been implicated in DI-TMA. We present the first case of a patient meeting clinical criteria for DI-TMA following admission for valproic acid toxicity. An adolescent male with difficult to control epilepsy was admitted for impaired hepatic function while on valproic acid therapy. On the third hospital day, he developed severe metabolic lactic acidosis and multiorgan failure, prompting transfer to the pediatric intensive care unit. Progressive anemia and thrombocytopenia instigated an evaluation for thrombotic microangiopathy, where confirmed by concomitant hemolysis, elevated lactate dehydrogenase (LDH), low haptoglobin, and concurrent oliguric acute kidney injury. Thrombotic thrombocytopenic purpura was less likely with adequate ADAMTS13. Discontinuing valproic acid reversed the anemia, thrombocytopenia, and normalized the LDH and haptoglobin, supporting a drug-induced cause for the TMA. To the best of our knowledge, this is the first report of drug-induced TMA from valproic acid toxicity.

Chapter 6: Selenium Toxicity to Aquatic Organisms

Science.gov (United States)

This chapter addresses the characteristics and nature of organic selenium (Se) toxicity to aquatic organisms, based on the most current state of scientific knowledge. As such, the information contained in this chapter relates to the 'toxicity assessment' phase of aquatic ecologi...

Impacts of select organic ligands on the colloidal stability, dissolution dynamics, and toxicity of silver nanoparticles.

Science.gov (United States)

Pokhrel, Lok R; Dubey, Brajesh; Scheuerman, Phillip R

2013-11-19

Key understanding of potential transformations that may occur on silver nanoparticle (AgNP) surface upon interaction with naturally ubiquitous organic ligands (e.g., -SH (thoil), humic acid, or -COO (carboxylate)) is limited. Herein we investigated how dissolved organic carbon (DOC), -SH (in cysteine, a well-known Ag(+) chelating agent), and -COO (in trolox, a well-known antioxidant) could alter the colloidal stability, dissolution rate, and toxicity of citrate-functionalized AgNPs (citrate-AgNPs) against a keystone crustacean Daphnia magna. Cysteine, DOC, or trolox amendment of citrate-AgNPs differentially modified particle size, surface properties (charge, plasmonic spectra), and ion release dynamics, thereby attenuating (with cysteine or trolox) or promoting (with DOC) AgNP toxicity. Except with DOC amendment, the combined toxicity of AgNPs and released Ag under cysteine or trolox amendment was lower than of AgNO3 alone. The results of this study show that citrate-AgNP toxicity can be associated with oxidative stress, ion release, and the organism biology. Our evidence suggests that specific organic ligands available in the receiving waters can differentially surface modify AgNPs and alter their environmental persistence (changing dissolution dynamics) and subsequently the toxicity; hence, we caveat to generalize that surface modified nanoparticles upon environmental release may not be toxic to receptor organisms.

Toxic Leadership in Educational Organizations

Science.gov (United States)

Green, James E.

2014-01-01

While research on the traits and skills of effective leaders is plentiful, only recently has the phenomenon of toxic leadership begun to be investigated. This research report focuses on toxic leadership in educational organizations--its prevalence, as well as the characteristics and early indicators. Using mixed methods, the study found four…

TOXICITY BEHAVIORS IN ORGANIZATIONS: STUDY OF RELIABILITY AND VALIDITY OF TOXIC EMOTIONAL EXPERIENCES SCALE

OpenAIRE

Bektas, Meral; Erkal, Pinar

2016-01-01

In toxic organizations which are mostly destructive instead of being constrictive towards its employees, toxicity behaviors emerge as a result of the formal and informal relationships. Toxicity behaviors are often negatively affect motivation, job satisfaction or performance of the employees in workplace. Basic toxicity behaviors in organizations are: extreme jealousy, biting words, emphasis  superiority emphasis, getting angry, offending employees, strict control, heavy job workload, limited...

Effects of Humic and Fulvic Acids on Silver Nanoparticle Stability, Dissolution, and Toxicity

Science.gov (United States)

Gunsolus, Ian L.; Mousavi, Maral P. S.; Hussein, Kadir; Bühlmann, Philippe; Haynes, Christy L.

2015-01-01

The colloidal stability of silver nanoparticles (AgNPs) in natural aquatic environments influences their transport and environmental persistence, while their dissolution to Ag+ influences their toxicity to organisms. Here, we characterize the colloidal stability, dissolution behavior, and toxicity of two industrially relevant classes of AgNPs (i.e., AgNPs stabilized by citrate or polyvinylpyrrolidone) after exposure to natural organic matter (NOM, i.e., Suwannee River Humic and Fulvic Acid Standards and Pony Lake Fulvic Acid Reference). We show that NOM interaction with the nanoparticle surface depends on (i) the NOM’s chemical composition, where sulfur- and nitrogen-rich NOM more significantly increases colloidal stability, and (ii) the affinity of the capping agent for the AgNP surface, where nanoparticles with loosely bound capping agents are more effectively stabilized by NOM. Adsorption of NOM is shown to have little effect on AgNP dissolution under most experimental conditions, the exception being when the NOM is rich in sulfur and nitrogen. Similarly, the toxicity of AgNPs to a bacterial model (Shewanella oneidensis MR-1) decreases most significantly in the presence of sulfur- and nitrogen-rich NOM. Our data suggest that the rate of AgNP aggregation and dissolution in aquatic environments containing NOM will depend on the chemical composition of the NOM, and that the toxicity of AgNPs to aquatic microorganisms is controlled primarily by the extent of nanoparticle dissolution. PMID:26047330

Toxicity of common ions to marine organisms

International Nuclear Information System (INIS)

Pillard, D.A.; DuFresne, D.L.; Evans, J.

1995-01-01

Produced waters from oil and gas drilling operations are typically very saline, and these may cause acute toxicity to marine organisms due to osmotic imbalances as well as to an excess or deficiency of specific common ions. In order to better understand the relationship between toxicity and ion concentration, laboratory toxicity tests were conducted using mysid shrimp (Mysidopsis bahia), sheepshead minnow (Cyprinodon variegatus), and inland silverside (Menidia beryllina). For each species the ionic concentration of standard laboratory water was proportionally increased or decreased to produce test solutions with a range of salinities. Organisms were exposed for 48 hours. Individual ions (sodium, potassium, calcium, magnetsium, strontium, chloride, bromide, sulfate, bicarbonate, and borate) were also manipulated to examine individual ion toxicity. The three test species differ in their tolerance of salinity. Mysid shrimp show a marked decrease in survival at salinities less than approximately 5 ppt. Both fish species tolerated low salinity water, however, silversides were less tolerant of saline waters (salinity greater than 40 ppt). There were also significant differences in the responses of the organisms to different ions. The results show that the salinity of the test solution may play an important role in the responses of the organisms to the produced water effluent. Predictable toxicity/ion relationships developed in this study can be used to estimate whether toxicity in a produced water is a result of common ions, salinity, or some other unknown toxicant

Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).

Science.gov (United States)

Berntssen, M H G; Sundal, T K; Olsvik, P A; Amlund, H; Rasinger, J D; Sele, V; Hamre, K; Hillestad, M; Buttle, L; Ørnsrud, R

2017-11-01

Depending on its chemical form, selenium (Se) is a trace element with a narrow range between requirement and toxicity for most vertebrates. Traditional endpoints of Se toxicity include reduced growth, feed intake, and oxidative stress, while more recent finding describe disturbance in fatty acid synthesis as underlying toxic mechanism. To investigate overall metabolic mode of toxic action, with emphasis on lipid metabolism, a wide scope metabolomics pathway profiling was performed on Atlantic salmon (Salmo salar) (572±7g) that were fed organic and inorganic Se fortified diets. Atlantic salmon were fed a low natural background organic Se diet (0.35mg Se kg -1 , wet weight (WW)) fortified with inorganic sodium selenite or organic selenomethionine-yeast (SeMet-yeast) at two levels (∼1-2 or 15mgkg -1 , WW), in triplicate for 3 months. Apparent adverse effects were assessed by growth, feed intake, oxidative stress as production of thiobarbituric acid-reactive substances (TBARS) and levels of tocopherols, as well as an overall metabolomic pathway assessment. Fish fed 15mgkg -1 selenite, but not 15mgkg -1 SeMet-yeast, showed reduced feed intake, reduced growth, increased liver TBARS and reduced liver tocopherol. Main metabolic pathways significantly affected by 15mgkg -1 selenite, and to a lesser extent 15mgkg -1 SeMet-yeast, were lipid catabolism, endocannabinoids synthesis, and oxidant/glutathione metabolism. Disturbance in lipid metabolism was reflected by depressed levels of free fatty acids, monoacylglycerols and diacylglycerols as well as endocannabinoids. Specific for selenite was the significant reduction of metabolites in the S-Adenosylmethionine (SAM) pathway, indicating a use of methyl donors that could be allied with excess Se excretion. Dietary Se levels to respectively 1.1 and 2.1mgkg -1 selenite and SeMet-yeast did not affect any of the above mentioned parameters. Apparent toxic mechanisms at higher Se levels (15mgkg -1 ) included oxidative stress and

Effect of organic acids on the growth and lipid accumulation of oleaginous yeast Trichosporon fermentans

Directory of Open Access Journals (Sweden)

Huang Chao

2012-01-01

Full Text Available Abstract Background Microbial lipids have drawn increasing attention in recent years as promising raw materials for biodiesel production, and the use of lignocellulosic hydrolysates as carbon sources seems to be a feasible strategy for cost-effective lipid fermentation with oleaginous microorganisms on a large scale. During the hydrolysis of lignocellulosic materials with dilute acid, however, various kinds of inhibitors, especially large amounts of organic acids, will be produced, which substantially decrease the fermentability of lignocellulosic hydrolysates. To overcome the inhibitory effects of organic acids, it is critical to understand their impact on the growth and lipid accumulation of oleaginous microorganisms. Results In our present work, we investigated for the first time the effect of ten representative organic acids in lignocellulosic hydrolysates on the growth and lipid accumulation of oleaginous yeast Trichosporon fermentans cells. In contrast to previous reports, we found that the toxicity of the organic acids to the cells was not directly related to their hydrophobicity. It is worth noting that most organic acids tested were less toxic than aldehydes to the cells, and some could even stimulate the growth and lipid accumulation at a low concentration. Unlike aldehydes, most binary combinations of organic acids exerted no synergistic inhibitory effects on lipid production. The presence of organic acids decelerated the consumption of glucose, whereas it influenced the utilization of xylose in a different and complicated way. In addition, all the organic acids tested, except furoic acid, inhibited the malic activity of T. fermentans. Furthermore, the inhibition of organic acids on cell growth was dependent more on inoculum size, temperature and initial pH than on lipid content. Conclusions This work provides some meaningful information about the effect of organic acid in lignocellulosic hydrolysates on the lipid production of

Gold leaching by organic base polythionates: new non-toxic and secure technology.

Science.gov (United States)

Smolyaninov, Vladislav; Shekhvatova, Galina; Vainshtein, Mikhail

2014-01-01

The article present a review on own experimental and some published data which are related with the gold leaching. It is well-known that the most common and usual process of the leaching with cyanide can be dangerous, needs a great water consumption, and additional costs for remediation of the poisoned and toxic sites. The experimental data described production of poythionates which are not toxic but perspective for the prosperous gold leaching. The paper dedicated to the safe gold leaching with thiosulfates and organic salts of polythionic acids (organic base polythionates). The method of production of these polythionates based on the Smolyaninov reaction is described in stages and in details for the first time. Possible application of the polythionates application in the gold leaching is discussed and its advantages are compared with the gold leaching by cyanation.

Yellow phosphorus process to convert toxic chemicals to non-toxic products

Science.gov (United States)

Chang, S.G.

1994-07-26

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

Reactions of clofibric acid with oxidative and reductive radicals—Products, mechanisms, efficiency and toxic effects

International Nuclear Information System (INIS)

Csay, Tamás; Rácz, Gergely; Salik, Ádám; Takács, Erzsébet; Wojnárovits, László

2014-01-01

The degradation of clofibric acid induced by hydroxyl radical, hydrated electron and O 2 −∙ /HO 2 ∙ reactive species was studied in aqueous solutions. Clofibric acid was decomposed more effectively by hydroxyl radical than by hydrated electron or O 2 −∙ /HO 2 ∙ . Various hydroxylated, dechlorinated and fragmentation products have been identified and quantified. A new LC–MS method was developed based on 18 O isotope labeling to follow the formation of hydroxylated derivatives of clofibric acid. Possible degradation pathways have been proposed. The overall degradation was monitored by determination of sum parameters like COD, TOC and AOX. It was found that the organic chlorine degrades very effectively prior to complete mineralization. After the treatment no toxic effect was found according to Vibrio fischeri tests. However, at early stages some of the reaction products were more harmful than clofibric acid. - Highlights: • Clofibric acid is effectively degraded by OH radical. • Main primary and secondary products are hydroxylated and dihydroxylated phenyl type derivatives of clofibric acid. • In air saturated aqueous solutions O 2 plays an important role in decomposition of the aromatic structure. • A new LC–MS method with 18 O-labeling was developed. • Early stage reaction products are more toxic to bacteria Vibrio fischeri than clofibric acid

Toxic effects of fluoride on organisms.

Science.gov (United States)

Zuo, Huan; Chen, Liang; Kong, Ming; Qiu, Lipeng; Lü, Peng; Wu, Peng; Yang, Yanhua; Chen, Keping

2018-04-01

Accumulation of excess fluoride in the environment poses serious health risks to plants, animals, and humans. This endangers human health, affects organism growth and development, and negatively impacts the food chain, thereby affecting ecological balance. In recent years, numerous studies focused on the molecular mechanisms associated with fluoride toxicity. These studies have demonstrated that fluoride can induce oxidative stress, regulate intracellular redox homeostasis, and lead to mitochondrial damage, endoplasmic reticulum stress and alter gene expression. This paper reviews the present research on the potential adverse effects of overdose fluoride on various organisms and aims to improve our understanding of fluoride toxicity. Copyright © 2018 Elsevier Inc. All rights reserved.

Consensus report on therapeutic drug monitoring of mycophenolic acid in solid organ transplantation

NARCIS (Netherlands)

D. Kuypers (Dirk); Y. le Meur (Yann); M. Cantarovich (Marcelo); M.J. Tredger (Michael); S.E. Tett (Susan); D. Cattaneo (Dario); B. Tönshoff (Burkhard); D.W. Holt (David); J. Chapman (Jeremy); T. van Gelder (Teun)

2010-01-01

textabstractWith the increasing use of mycophenolic acid (MPA) in solid organ transplantation, the need for more accurate drug dosing has become evident. Personalized immunosuppressive therapy requires better strategies for avoidance of drug-related toxicity while maintaining efficacy. Few studies

Toxicity and metal speciation in acid mine drainage treated by passive bioreactors

Energy Technology Data Exchange (ETDEWEB)

Neculita, C.M.; Vigneaul, B.; Zagury, G.J. [Ecole Polytechnic, Montreal, PQ (Canada)

2008-08-15

Sulfate-reducing passive bioreactors treat acid mine drainage (AMD) by increasing its pH and alkalinity and by removing metals as metal sulfide precipitates. In addition to discharge limits based on physicochemical parameters, however, treated effluent is required to be nontoxic. Acute and sublethal toxicity was assessed for effluent from 3.5-L column bioreactors filled with mixtures of natural organic carbon sources and operated at different hydraulic retention times (HRTs) for the treatment of a highly contaminated AMD. Effluent was first tested for acute (Daphnia magna and Oncorhynchus mykiss) and sublethal (Pseudokirchneriella subcapitata, Ceriodaphnia dabia, and Lemna minor) toxicity. Acute toxicity was observed for D. magna, and a toxicity identification evaluation (TIE) procedure was then performed to identify potential toxicants. Finally, metal speciation in the effluent was determined using ultrafiltration and geochemical modeling for the interpretation of the toxicity results. The 10-d HRT effluent was nonacutely lethal for 0. mykiss but acutely lethal for D. magna. The toxicity to D. magna, however, was removed by 2 h of aeration, and the TIE procedure suggested iron as a cause of toxicity. Sublethal toxicity of the 10-d HRT effluent was observed for all test species, but it was reduced compared to the raw AMD and to a 7.3-d HRT effluent. Data regarding metal speciation indicated instability of both effluents during aeration and were consistent with the toxicity being caused by iron. Column bioreactors in operation for more than nine months efficiently improved the physicochemical quality of highly contaminated AMD at different HRTs.

On the Toxicity of the Aromatic Diamines and their Tetramethylcarboxylic Acid Derivatives

OpenAIRE

Gili, Pedro; Mederos, Alfredo

2000-01-01

The use of the theoretical PALLAS 3.0 program, to study the toxic behaviour of tetramethylcarboxylic acids, potential pharmaceuticals derived from o-phenylenediamines, indicates that o-phenylenediamines are highly toxic (level 1), while the tetramethycarboxylic acid derivatives (o-PhDTA and 3,4-TDTA) are slightly toxic, similar to EDTA (level 3). Therefore these ligands o-PhDTA and 3,4-TDTA, similar to EDTA, can be used as sequestering agents of toxic metals and overload of essential metals i...

Plant-associated bacterial degradation of toxic organic compounds in soil.

LENUS (Irish Health Repository)

McGuinness, Martina

2009-08-01

A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review.

[Aluminum--occurrence and toxicity for organisms].

Science.gov (United States)

Ochmański, W; Barabasz, W

2000-01-01

Aluminium (Al.) is an ubiquitous element found in every food product. The sources of Al. are especially corn, yellow cheese, salt, herbs, spices, tea and tap water. In household Al.-made ware is a major source of the element. Al. may cause diseases in humans, especially hampers many metabolic processes especially turnover of calcium, phosphorus and iron. Salts of Al. may bind to DNA, RNA, inhibit such enzymes as hexokinase, acid and alkaline phosphatases, phosphodiesterase and phosphooxydase. Al. salts are especially harmful to nervous, hematopoietic systems and to skeleton. Al. gets to organism with food, water, cosmetics, from aluminium ware and containers. Toxicity comes from substitution of Mg and Fe ions effecting in disturbances in intracellular signaling, excretory functions and cellular growth. Neurotoxic action of Al. probably comes from substitution of Mg ions in ATP, what finally influences function of every ATP using-enzymes. There are observations in experimental models proving Al. salts are responsible for Alzheimer disease development. Toxicity of Al. to skeletal system results in diminished resistance thus tendencies to breaking, and comes from lower collagen synthesis and slowing down of mineralisation. Low erythropoietin production, inhibition of hem-synthesing enzymes and binding of Al. to transferrin, effects in anaemia. Carcinogenic effects of Al. were nor proved nor denied, but high concentrations of Al. were found in many neoplastic cells. In conclusion, we should introduce prophylactic measures effecting in less Al. intake esp. avoiding use of Al.-made ware nad controlling food for Al. content.

Acute toxicity of anionic and non-ionic surfactants to aquatic organisms.

Science.gov (United States)

Lechuga, M; Fernández-Serrano, M; Jurado, E; Núñez-Olea, J; Ríos, F

2016-03-01

The environmental risk of surfactants requires toxicity measurements. As different test organisms have different sensitivity to the toxics, it is necessary to establish the most appropriate organism to classify the surfactant as very toxic, toxic, harmful or safe, in order to establish the maximum permissible concentrations in aquatic ecosystems. We have determined the toxicity values of various anionic surfactants ether carboxylic derivatives using four test organisms: the freshwater crustacean Daphnia magna, the luminescent bacterium Vibrio fischeri, the microalgae Selenastrum capricornutum (freshwater algae) and Phaeodactylum tricornutum (seawater algae). In addition, in order to compare and classify the different families of surfactants, we have included a compilation of toxicity data of surfactants collected from literature. The results indicated that V. fischeri was more sensitive to the toxic effects of the surfactants than was D. magna or the microalgae, which was the least sensitive. This result shows that the most suitable toxicity assay for surfactants may be the one using V. fischeri. The toxicity data revealed considerable variation in toxicity responses with the structure of the surfactants regardless of the species tested. The toxicity data have been related to the structure of the surfactants, giving a mathematical relationship that helps to predict the toxic potential of a surfactant from its structure. Model-predicted toxicity agreed well with toxicity values reported in the literature for several surfactants previously studied. Predictive models of toxicity is a handy tool for providing a risk assessment that can be useful to establish the toxicity range for each surfactant and the different test organisms in order to select efficient surfactants with a lower impact on the aquatic environment. Copyright © 2015 Elsevier Inc. All rights reserved.

A review of the nature of naphthenic acid occurrence, toxicity, and fate in refinery and oil sands extraction wastewaters

Energy Technology Data Exchange (ETDEWEB)

Eickhoff [Maxxam, Calgary, AB (Canada)

2010-07-01

This PowerPoint presentation evaluated the occurrence, toxicity and fate of naphthenic acids (NA) in refinery and oil sands extraction waste waters. The chemistry of NA was reviewed. Factors affecting the aquatic toxicity of NA were discussed, and modes of toxicity were outlined. NA residues in fish were evaluated. Issues concerning the biodegradation, photolysis, and phytodegradation of NA were reviewed. Various phytoremediation techniques were presented. Results of the study indicated that acute toxicity to aquatic organisms was caused by narcosis. Sublethal impacts of NA included changes to growth, fertilization, reproduction, development, and hormone modifications. Varying rates of toxicity were observed in different NA, based on their size and molecular structure. While biodegradation can reduce the toxicity of NA, higher molecular weight NA can resist degradation and cause toxicity. tabs., figs.

Direct Capture of Organic Acids From Fermentation Media Using Ionic Liquids

Energy Technology Data Exchange (ETDEWEB)

Klasson, K.T.

2004-11-03

Several ionic liquids have been investigated for the extraction of organic acids from fermentation broth. Partitioning of representative organic acids (lactic, acetic, and succinic) between aqueous solution and nine hydrophobic ionic liquids was measured. The extraction efficiencies were strongly dependent on pH of the aqueous phase. Distribution coefficient was very good (approximately 60) at low succinic acid concentrations for one of the ionic liquids (trihexyltetradecylphosphonium methanesulfonate) at neutral pH. However, this ionic liquid had to be diluted with nonanol due to its high viscosity in order to be useful. A diluent (trioctylamine) was also added to this mixture. The results suggest that an extraction system based on ionic liquids may be feasible for succinic acid recovery from fermentation broth and that two ideal extraction stages are needed to reduce the concentration from 33 g/L to 1 g/L of succinic acid. Further studies are needed to evaluate other issues related to practical applications, including ionic liquid loss in the process, toxicity effects of ionic liquids during simultaneous fermentation and extractions.

The developmental toxicity of perfluoroalkyl acids and their derivatives

International Nuclear Information System (INIS)

Lau, Christopher; Butenhoff, John L.; Rogers, John M.

2004-01-01

Perfluoroalkyl acids such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have applications in numerous industrial and consumer products. Although the toxicology of some of these compounds has been investigated in the past, the widespread prevalence of PFOS and PFOA in humans, as demonstrated in recent bio-monitoring studies, has drawn considerable interest from the public and regulatory agencies as well as renewed efforts to better understand the hazards that may be inherent in these compounds. This review provides a brief overview of the perfluoroalkyl chemicals and a summary of the available information on the developmental toxicity of the eight-carbon compounds, PFOS and PFOA. Although the teratological potentials of some of these chemicals had been studied in the past and the findings were generally unremarkable, results from recent postnatal studies on developmental and reproductive indices have prompted consideration of their relevance to human health risk. Based on current understanding of the developmental effects of PFOS and PFOA in rodents, several avenues of research are suggested that would further support the risk assessment of these perfluorinated organic chemicals

A novel approach for rapidly and cost-effectively assessing toxicity of toxic metals in acidic water using an acidophilic iron-oxidizing biosensor.

Science.gov (United States)

Yang, Shih-Hung; Cheng, Kuo-Chih; Liao, Vivian Hsiu-Chuan

2017-11-01

Contamination by heavy metals and metalloids is a serious environmental and health concern. Acidic wastewaters are often associated with toxic metals which may enter and spread into agricultural soils. Several biological assays have been developed to detect toxic metals; however, most of them can only detect toxic metals in a neutral pH, not in an acidic environment. In this study, an acidophilic iron-oxidizing bacterium (IOB) Strain Y10 was isolated, characterized, and used to detect toxic metals toxicity in acidic water at pH 2.5. The colorimetric acidophilic IOB biosensor was based on the inhibition of the iron oxidizing ability of Strain Y10, an acidophilic iron-oxidizing bacterium, by metals toxicity. Our results showed that Strain Y10 is acidophilic iron-oxidizing bacterium. Thiobacillus caldus medium (TCM) (pH 2.5) supplied with both S 4 O 6 2- and glucose was the optimum growth medium for Strain Y10. The optimum temperature and pH for the growth of Strain Y10 was 45 °C and pH 2.5, respectively. Our study demonstrates that the color-based acidophilic IOB biosensor can be semi-quantitatively observed by eye or quantitatively measured by spectrometer to detect toxicity from multiple toxic metals at pH 2.5 within 45 min. Our study shows that monitoring toxic metals in acidic water is possible by using the acidophilic IOB biosensor. Our study thus provides a novel approach for rapid and cost-effective detection of toxic metals in acidic conditions that can otherwise compromise current methods of chemical analysis. This method also allows for increased efficiency when screening large numbers of environmental samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fractionation of fulvic acid by iron and aluminum oxides: influence on copper toxicity to Ceriodaphnia dubia

Science.gov (United States)

Smith, Kathleen S.; Ranville, James F.; Lesher, Emily K.; Diedrich, Daniel J.; McKnight, Diane M.; Sofield, Ruth M.

2014-01-01

This study examines the effect on aquatic copper toxicity of the chemical fractionation of fulvic acid (FA) that results from its association with iron and aluminum oxyhydroxide precipitates. Fractionated and unfractionated FAs obtained from streamwater and suspended sediment were utilized in acute Cu toxicity tests on ,i>Ceriodaphnia dubia. Toxicity test results with equal FA concentrations (6 mg FA/L) show that the fractionated dissolved FA was 3 times less effective at reducing Cu toxicity (EC50 13 ± 0.6 μg Cu/L) than were the unfractionated dissolved FAs (EC50 39 ± 0.4 and 41 ± 1.2 μg Cu/L). The fractionation is a consequence of preferential sorption of molecules having strong metal-binding (more aromatic) moieties to precipitating Fe- and Al-rich oxyhydroxides, causing the remaining dissolved FA to be depleted in these functional groups. As a result, there is more bioavailable dissolved Cu in the water and hence greater potential for Cu toxicity to aquatic organisms. In predicting Cu toxicity, biotic ligand models (BLMs) take into account dissolved organic carbon (DOC) concentration; however, unless DOC characteristics are accounted for, model predictions can underestimate acute Cu toxicity for water containing fractionated dissolved FA. This may have implications for water-quality criteria in systems containing Fe- and Al-rich sediment, and in mined and mineralized areas in particular. Optical measurements, such as specific ultraviolet absorbance at 254 nm (SUVA254), show promise for use as spectral indicators of DOC chemical fractionation and inferred increased Cu toxicity.

Assessing toxicity of varying major ion concentrations to marine organisms

International Nuclear Information System (INIS)

Mount, D.R.; Quast, W.

1993-01-01

Recent regulatory developments have required that produced waters discharged in the Gulf of Mexico be monitored for toxicity to marine organisms. While produced water may contain a variety of indigenous and introduced chemicals, virtually all have moderate to high concentrations of major ions. Although seawater is also rich in these ions, excessive salinity can cause toxicity to marine organisms. Perhaps more importantly, toxicity to marine organisms can be caused by deviations from normal ion ratios even if the total salinity is within organism tolerances. To provide a better understanding of marine organism responses to variations in major ion concentrations, the authors conducted a series of laboratory experiments to quantify the responses of mysid shrimp (Mysidopsis bahia) and sheepshead minnows (Cyprinodon variegatus) to modifications of normal seawater chemistry. Acute testing included both increasing and decreasing the concentrations of individual ions relative to seawater, as well as altering total salinity. Results show these organisms can be adversely affected by this altered chemistry and their sensitivity is dependent upon the individual ions that are manipulated. Results from these studies are being incorporated into an overall strategy for evaluating the influence of major ion chemistry on produced water toxicity tests

Effect of water hardness on peracetic acid toxicity to zebrafish, Danio rerio, embryos

DEFF Research Database (Denmark)

Marchand, Pierre_André; Strauss, David L.; Wienke, Andreas

2013-01-01

The use of peracetic acid (PAA) in aquaculture has been suggested as an alternative therapeutic agent. Few data are available concerning fish toxicity by PAA or factors that modify this toxicity. The aim of this study was to investigate the influence of water hardness on the acute toxicity of PAA...... acidic in low hardness. In conclusion, aquaculturists using PAA should pay attention to water hardness to avoid acidosis...

Proton and aluminum binding properties of organic acids in surface waters of the northeastern U.S.

Science.gov (United States)

Fakhraei, Habibollah; Driscoll, Charles T

2015-03-03

A variety of mathematical estimators have been used to quantify the degree of protonation of naturally occurring organic acids. These estimators range from monoprotic, diprotic, and triprotic analog models to the discrete and continuous (Gaussian) distributions of a single proton binding-dissociation. Natural water samples from two long-term monitoring programs in the northeastern U.S. were used to quantify proton- and aluminum-binding properties of naturally occurring organic matter. Water chemistry observations were clustered into 0.05 pH intervals (over 3.75-7.35 pH range) and fit to a triprotic analog model. The model optimization indicates that about 5% of dissolved organic carbon participates in ion binding, and organic acids are composed of both strong and weak acids (i.e., pKa1 = 2.54, pKa2 = 6.19, and pKa3 = 7.52 for Adirondack samples). Binding between organic acids and aluminum can substantially influence the acid behavior of dissolved organic matter and the availability of the toxic form of aluminum (i.e., inorganic monomeric aluminum).

Lactic Acid Bacteria Protects Caenorhabditis elegans from Toxicity of Graphene Oxide by Maintaining Normal Intestinal Permeability under different Genetic Backgrounds

Science.gov (United States)

Zhao, Yunli; Yu, Xiaoming; Jia, Ruhan; Yang, Ruilong; Rui, Qi; Wang, Dayong

2015-11-01

Lactic acid bacteria (LAB) is safe and useful for food and feed fermentation. We employed Caenorhabditis elegans to investigate the possible beneficial effect of LAB (Lactobacillus bulgaricus) pretreatment against toxicity of graphene oxide (GO) and the underlying mechanisms. LAB prevented GO toxicity on the functions of both primary and secondary targeted organs in wild-type nematodes. LAB blocked translocation of GO into secondary targeted organs through intestinal barrier by maintaining normal intestinal permeability in wild-type nematodes. Moreover, LAB prevented GO damage on the functions of both primary and secondary targeted organs in exposed nematodes with mutations of susceptible genes (sod-2, sod-3, gas-1, and aak-2) to GO toxicity by sustaining normal intestinal permeability. LAB also sustained the normal defecation behavior in both wild-type nematodes and nematodes with mutations of susceptible genes. Therefore, the beneficial role of LAB against GO toxicity under different genetic backgrounds may be due to the combinational effects on intestinal permeability and defecation behavior. Moreover, the beneficial effects of LAB against GO toxicity was dependent on the function of ACS-22, homologous to mammalian FATP4 to mammalian FATP4. Our study provides highlight on establishment of pharmacological strategy to protect intestinal barrier from toxicity of GO.

Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay

International Nuclear Information System (INIS)

Gerhardt, A.; Janssens de Bisthoven, L.; Soares, A.M.V.M.

2004-01-01

The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor[reg], based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC 50 -48 h: pH-AMD=5.8) and a pH- dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC 50 -48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed. - Toxicity of acid mine drainage was evaluated by macroinvertebrate bioassessment and a new on-line rapid behavioural toxicity test with Atyaephyra desmaresti (Crustacea)

Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay

Energy Technology Data Exchange (ETDEWEB)

Gerhardt, A.; Janssens de Bisthoven, L.; Soares, A.M.V.M

2004-07-01

The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor[reg], based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC{sub 50}-48 h: pH-AMD=5.8) and a pH- dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC{sub 50}-48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed. - Toxicity of acid mine drainage was evaluated by macroinvertebrate bioassessment and a new on-line rapid behavioural toxicity test with Atyaephyra desmaresti (Crustacea)

Zinc oxide nanoparticle toxicity in embryonic zebrafish: Mitigation with different natural organic matter.

Science.gov (United States)

Kteeba, Shimaa M; El-Adawi, Hala I; El-Rayis, Osman A; El-Ghobashy, Ahmed E; Schuld, Jessica L; Svoboda, Kurt R; Guo, Laodong

2017-11-01

Exposure experiments were conducted to evaluate the influence of dissolved organic matter (DOM) on the toxicity of ZnO-NPs (10-30 nm) and dissolved Zn at sub-lethal doses (50 and 5 ppm, respectively) to zebrafish (Danio rerio). Humic acid, alginic acid, bovine serum albumin and various natural DOM isolated from rivers as the Milwaukee River-WI (NOMW), Yukon River-AK (NOMA) and Suwannee River-GA DOM (NOMS) were used to represent humic substances (HA), carbohydrates (CHO), proteins (PTN), and natural organic matter (NOM), respectively. Initial experiments were carried out to confirm the toxic effect of ZnO-NPs at 50 ppm, followed by mitigation experiments with different types and concentrations of DOM (0.4-40 mg-C/L). Compared to 0% hatch of 50 ppm ZnO-NPs exposed embryos at 72 h post fertilization (hpf), NOMS, NOMW and HA had the best mitigative effects on hatching (53-65%), followed by NOMA, CHO and PTN (19-35%); demonstrating that the mitigation effects on ZnO-NPs toxicity were related to DOM's quantity and composition. At 96 hpf, 20% of embryos exposed to 50 ppm ZnO-NPs hatched, 100% of embryos reared in embryo medium hatched, and close to 100% of the embryos hatched upon mitigation, except for those mitigated with PTN which had less effect. Dissolved Zn (5 ppm) also exhibited the same toxicity on embryos as ZnO-NPs (50 ppm). However, in the presence of HA, NOM and CHO, the hatching rates at 72 and 96 hpf increased significantly compared to 5% hatch without DOM. The overall mitigation effects produced by DOM followed the order of HA ≥ NOMS > NOM (A&W) > CHO > PTN, although specific mitigation effects varied with DOM concentration and functionalities. Our results also indicate that the toxicity of ZnO-NPs to embryos was mostly derived from NPs although dissolved Zn released from ZnO-NPs also interacted with embryos, affecting hatching, but to a less extent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular Mechanisms of Ursodeoxycholic Acid Toxicity & Side Effects: Ursodeoxycholic Acid Freezes Regeneration & Induces Hibernation Mode

Science.gov (United States)

Kotb, Magd A.

2012-01-01

Ursodeoxycholic acid (UDCA) is a steroid bile acid approved for primary biliary cirrhosis (PBC). UDCA is reported to have “hepato-protective properties”. Yet, UDCA has “unanticipated” toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively). “Unanticipated” UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day) and toxic dose (28 mg/kg/day), and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified. PMID:22942741

Molecular Mechanisms of Ursodeoxycholic Acid Toxicity & Side Effects: Ursodeoxycholic Acid Freezes Regeneration & Induces Hibernation Mode

Directory of Open Access Journals (Sweden)

Magd A. Kotb

2012-07-01

Full Text Available Ursodeoxycholic acid (UDCA is a steroid bile acid approved for primary biliary cirrhosis (PBC. UDCA is reported to have “hepato-protective properties”. Yet, UDCA has “unanticipated” toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively. “Unanticipated” UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day and toxic dose (28 mg/kg/day, and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified.

[Inhibition of Low Molecular Organic Acids on the Activity of Acidithiobacillus Species and Its Effect on the Removal of Heavy Metals from Contaminated Soil].

Science.gov (United States)

Song, Yong-wei; Wang, He-rul; Cao, Yan-xiao; Li, Fei; Cui, Chun-hong; Zhou, Li

2016-05-15

Application of organic fertilizer can reduce the solubility and bioavailability of heavy metals in contaminated soil, but in the flooded anaerobic environment, organic fertilizer will be decomposed to produce a large number of low molecular organic acids, which can inhibit the biological activity of Acidithiobacillus species. Batch cultures studies showed that the monocarboxylic organic acids including formic acid, acetic acid, propionic acid, and butyric acid exhibited a marked toxicity to Acidithiobacillus species, as indicated by that 90% of inhibitory rate for Fe2 and So oxidation in 72 h were achieved at extremely low concentrations of 41.2 mg · L⁻¹, 78.3 mg · L⁻¹, 43.2 mg · L⁻¹, 123.4 mg · L⁻¹ and 81.9 mg 230. 4 mg · L⁻¹, 170.1 mg · L⁻¹, 123.4 mg · L⁻¹ respectively. Of these organic acids, formic acid was the most toxic one as indicated by that Fe2 and So oxidation was almost entirely inhibited at a low concentration. In addition, it was found that Acidithiobacillus ferrooxidans was more sensitive to low molecular organic acids than Acidithiobacillus thiooxidans. What's more, there was little effect on biological acidification process of heavy metal contaminated soil when organic acids were added at initial stage (Oh), but it was completely inhibited when these acids were added after 12 h of conventional biological acidification, thus decreasing the efficiency of heavy metals dissolution from soil.

Toxicity of penicillic acid for rat alveolar macrophages in vitro

International Nuclear Information System (INIS)

Sorenson, W.G.; Simpson, J.

1985-01-01

Penicillic acid (PA) is a polyketide mycotoxin produced by several species of Aspergillus and Penicillium. This mycotoxin is toxic in experimental animals and has also been reported to be carcinogenic. The cytotoxicity of penicillic acid was studied in rat albeolar macrophages (AM) in vitro. The effects of penicillic acid on membrane integrity were studied by measuring cell volume changes and 51 Cr release. There was a significant decrease in adenosine triphosphate (ATP) in cell cultures exposed to 1.0 mM penicillic acid for 4 hr. Inhibition of the incorporation of [ 3 H]leucine into protein was both dose- and time-dependent and protein synthesis was inhibited significantly after 2 hr exposure to ≥0.1 mM penicillic acid. RNA synthesis was inhibited to a lesser extent than protein synthesis. There was significant inhibition of phagocytosis after 2 hr exposure at ≥0.3 mM penicillic acid and the ED 50 for phagocytosis was 0.09 mM. Thus phagocytosis was more sensitive to the toxic effects of penicillic acid than any other cellular process studied. The data suggest the possibility of a respiratory hazard to agricultural workers exposed to contaminated grain

Reactions of clofibric acid with oxidative and reductive radicals-Products, mechanisms, efficiency and toxic effects

Science.gov (United States)

Csay, Tamás; Rácz, Gergely; Salik, Ádám; Takács, Erzsébet; Wojnárovits, László

2014-09-01

The degradation of clofibric acid induced by hydroxyl radical, hydrated electron and O2-•/HO2• reactive species was studied in aqueous solutions. Clofibric acid was decomposed more effectively by hydroxyl radical than by hydrated electron or O2-•/HO2•. Various hydroxylated, dechlorinated and fragmentation products have been identified and quantified. A new LC-MS method was developed based on 18O isotope labeling to follow the formation of hydroxylated derivatives of clofibric acid. Possible degradation pathways have been proposed. The overall degradation was monitored by determination of sum parameters like COD, TOC and AOX. It was found that the organic chlorine degrades very effectively prior to complete mineralization. After the treatment no toxic effect was found according to Vibrio fischeri tests. However, at early stages some of the reaction products were more harmful than clofibric acid.

Multi-Organ toxicity demonstration in a functional human in vitro system composed of four organs.

Science.gov (United States)

Oleaga, Carlota; Bernabini, Catia; Smith, Alec S T; Srinivasan, Balaji; Jackson, Max; McLamb, William; Platt, Vivien; Bridges, Richard; Cai, Yunqing; Santhanam, Navaneetha; Berry, Bonnie; Najjar, Sarah; Akanda, Nesar; Guo, Xiufang; Martin, Candace; Ekman, Gail; Esch, Mandy B; Langer, Jessica; Ouedraogo, Gladys; Cotovio, Jose; Breton, Lionel; Shuler, Michael L; Hickman, James J

2016-02-03

We report on a functional human model to evaluate multi-organ toxicity in a 4-organ system under continuous flow conditions in a serum-free defined medium utilizing a pumpless platform for 14 days. Computer simulations of the platform established flow rates and resultant shear stress within accepted ranges. Viability of the system was demonstrated for 14 days as well as functional activity of cardiac, muscle, neuronal and liver modules. The pharmacological relevance of the integrated modules were evaluated for their response at 7 days to 5 drugs with known side effects after a 48 hour drug treatment regime. The results of all drug treatments were in general agreement with published toxicity results from human and animal data. The presented phenotypic culture model exhibits a multi-organ toxicity response, representing the next generation of in vitro systems, and constitutes a step towards an in vitro "human-on-a-chip" assay for systemic toxicity screening.

Acute toxicity of birch tar oil on aquatic organisms

Directory of Open Access Journals (Sweden)

M. HAGNER

2008-12-01

Full Text Available Birch tar oil (BTO is a by-product of processing birch wood in a pyrolysis system. Accumulating evidence suggests the suitability of BTO as a biocide or repellent in terrestrial environments for the control of weeds, insects, molluscs and rodents. Once applied as biocide, BTO may end up, either through run-off or leaching, in aquatic systems and may have adverse effects on non-target organisms. As very little is known about the toxicity of BTO to aquatic organisms, the present study investigated acute toxicity (LC50/EC50 of BTO for eight aquatic organisms. Bioassays with the Asellus aquaticus (crustacean, Lumbriculus variegatus (oligochaeta worm, Daphnia magna (crustacean, Lymnea sp. (mollusc, Lemna minor (vascular plant, Danio rerio (fish, Scenedesmus gracilis (algae, and Vibrio fischeri (bacterium were performed according to ISO, OECD or USEPA-guidelines. The results indicated that BTO was practically nontoxic to most aquatic organisms as the median effective BTO concentrations against most organisms were >150 mg L-1. In conclusion, our toxicity tests showed that aquatic organisms are to some extent, invariably sensitive to birch tar oil, but suggest that BTO does not pose a severe hazard to aquatic biota. We deduce that, unless BTOs are not applied in the immediate vicinity of water bodies, no special precaution is required.;

Is Boric Acid Toxic to Reproduction in Humans? Assessment of the Animal Reproductive Toxicity Data and Epidemiological Study Results.

Science.gov (United States)

Duydu, Yalçın; Başaran, Nurşen; Ustündağ, Aylin; Aydın, Sevtap; Undeğer, Ulkü; Ataman, Osman Yavuz; Aydos, Kaan; Düker, Yalçın; Ickstadt, Katja; Waltrup, Brita Schulze; Golka, Klaus; Bolt, Hermann Maximilian

2016-01-01

Boric acid and sodium borates are classified as toxic to reproduction in the CLP Regulation under "Category 1B" with the hazard statement of "H360FD". This classification is based on the reprotoxic effects of boric acid and sodium borates in animal experiments at high doses. However, boron mediated reprotoxic effects have not been proven in epidemiological studies so far. The epidemiological study performed in Bandırma boric acid production plant is the most comprehensive published study in this field with 204 voluntarily participated male workers. Sperm quality parameters (sperm morphology, concentration and motility parameters), FSH, LH and testosterone levels were determined in all participated employees as the reproductive toxicity biomarkers of males. However, boron mediated unfavorable effects on reproduction in male workers have not been determined even in the workers under very high daily boron exposure (0.21 mg B/kg-bw/day) conditions. The NOAEL for rat reproductive toxicity is equivalent to a blood boron level of 2020 ng/g. This level is higher than the mean blood boron concentration (223.89 ± 69.49 ng/g) of the high exposure group workers in Bandırma boric acid production plant (Turkey) by a factor of 9. Accordingly, classifying boric acid and sodium borates under "Category 1B" as "presumed reproductive human toxicant in the CLP regulation seems scientifically not reasonable. The results of the epidemiological studies (including the study performed in China) support for a down-classification of boric acid from the category 1B, H360FD to category 2, H361d, (suspected of damaging the unborn child).

Toxicity of perfluorooctanoic acid towards earthworm and enzymatic activities in soil.

Science.gov (United States)

He, Wenxiang; Megharaj, Mallavarapu; Naidu, Ravi

2016-07-01

Perfluorooctanoic acid (PFOA) is a widespread persistent organic contaminant in the environment that has recently raised much of regulatory and public concern. Therefore, assessment of its ecological risk is a top priority research. Hence, this study investigated the toxicity of PFOA to beneficial microbial processes in the soil such as activities of dehydrogenase, urease and potential nitrification in addition to earthworm survival, weight loss and PFOA bioaccumulation in two contrasting soils. In general, PFOA caused inhibition of all the measured microbial processes in a dose-dependent manner and the inhibition was higher in Williamtown (WT) soil than Edinburgh (EB) soil. Thus, WT soil being sandy in nature with low clay content showed higher PFOA bioavailability and hence showed higher toxicity. There was no mortality in earthworms exposed up to 100 mg PFOA/kilogram soil in both the soils; however, there was a significant weight loss from 25 mg/kg onwards. This study clearly demonstrates that soil contamination of PFOA can lead to adverse effects on soil health.

Technetium and diazotrophic organisms: toxicity, localization, transfer factors

International Nuclear Information System (INIS)

Vandecasteele, C.M.; Delmotte, A.; Roucoux, P.; Hove, C. van

1982-01-01

Three diazotrophic organisms, together with one leguminous organism in symbiosis with one of them, were cultivated in the presence of various quantities of technetium, of which the localization, transfer factors and toxicity were studied in relation to the age of the organisms and their type of metabolism. The paper discusses the biochemical aspects of the results. (author)

Assessment of melamine and cyanuric acid toxicity in cats.

Science.gov (United States)

Puschner, Birgit; Poppenga, Robert H; Lowenstine, Linda J; Filigenzi, Michael S; Pesavento, Patricia A

2007-11-01

The major pet food recall associated with acute renal failure in dogs and cats focused initially on melamine as the suspect toxicant. In the course of the investigation, cyanuric acid was identified in addition to melamine in the offending food. The purpose of this study was to characterize the toxicity potential of melamine, cyanuric acid, and a combination of melamine and cyanuric acid in cats. In this pilot study, melamine was added to the diet of 2 cats at 0.5% and 1%, respectively. Cyanuric acid was added to the diet of 1 cat at increasing doses of 0.2%, 0.5%, and 1% over the course of 10 days. Melamine and cyanuric acid were administered together at 0%, 0.2%, 0.5%, and 1% to 1 cat per dose group. No effect on renal function was observed in cats fed with melamine or cyanuric acid alone. Cats dosed with a combination were euthanized at 48 hours after dosing because of acute renal failure. Urine and touch impressions of kidneys from all cats dosed with the combination revealed the presence of fan-shaped, birefringent crystals. Histopathologic findings were limited to the kidneys and included crystals primarily within tubules of the distal nephron, severe renal interstitial edema, and hemorrhage at the corticomedullary junction. The kidneys contained estimated melamine concentrations of 496 to 734 mg/kg wet weight and estimated cyanuric acid concentrations of 487 to 690 mg/kg wet weight. The results demonstrate that the combination of melamine and cyanuric acid is responsible for acute renal failure in cats.

USE OF POWDERED COCONUT CHARCOAL AS A TOXICITY IDENTIFICATION AND EVALUATION MANIPULATION FOR ORGANIC TOXICANTS IN MARINE SEDIMENTS

Science.gov (United States)

We report on a procedure using powdered coconut charcoal to sequester organic contaminants and reduce toxicity in sediments as part of a series of toxicity identification and evaluation (TIE) methods. Powdered coconut charcoal (PCC) was effective in reducing the toxicity of endos...

Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay

Energy Technology Data Exchange (ETDEWEB)

A. Gerhardt; L. Janssens de Bisthoven; A.M.V.M. Soares [University of Aveiro, Aveiro (Portugal). Department of Biology

2004-07-01

The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor{reg_sign}, based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC{sub 50}-48 h: pH-AMD=5.8) and a pH-dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC{sub 50}-48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed.

Temperature influence on chemical toxicity to aquatic organisms

International Nuclear Information System (INIS)

Cairns, J. Jr.; Heath, A.G.; Parker, B.C.

1975-01-01

The literature on the effects of temperature on chemical toxicity to aquatic animals and microorganisms is reviewed. Microbial photosynthesis and respiration is briefly discussed. It is concluded that there is a paucity of information on the inter-relations of temperature and toxicants to algae, bacteria, and protozoa and that standards based on the in situ response of indigenous organisms to specific discharge areas should be developed

Toxicity of aluminium in natural waters controlled by type rather than quantity of natural organic matter

International Nuclear Information System (INIS)

Papathanasiou, Grigorios; White, Keith N.; Walton, Rachel; Boult, Stephen

2011-01-01

Extension of the conditions under which Al toxicity is tested is required. Environmentally representative preparation of waters is used in investigating roles of alginate (AA) and humic acids (HA) in partitioning of Al (0.5 mg L -1 ), subsequent uptake and accumulation by and toxicity to Lymnaea stagnalis. HA and AA did not alter precipitation of Al(OH) 3 , but altered subsequent behaviour of Al. High (40 mg L -1 ) HA concentrations, and to a lesser extent AA, prevented settling and availability for benthic grazing but made deposited Al more likely to be ingested. HA detoxified but AA increased toxicity relative to Al alone. Low concentration (4 mg L -1 ) AA and HA do not change partitioning but increase uptake; they both detoxify, but AA less than HA. The study shows OC:Al ratio is critical in predicting Al behaviour in natural waters, also uptake is mediated by snail behaviour, not solely a function of concentration and form of Al. Therefore, predicting Al behaviour will be subject to errors in determining relevant water composition and response of biota to the new speciation. However, with respect to toxicity, rather than other aspects of Al behaviour, different ratios of HA and Al are insignificant compared to whether AA is present rather than HA. - Highlights: → Toxicity assessment in which environmental relevance is of primary concern. → Mass balance of Al monitored throughout the exposure period. → Al behaviour influenced by concentration of organic matter. → Strong dependence of toxicity on type rather than concentration of organic matter. → Toxicity is a function of Al behaviour but also animal behaviour.

Toxicity of nickel and silver to Nostoc muscorum: interaction with ascorbic acid, glutathione, and sulfur-containing amino acids.

Science.gov (United States)

Rai, L C; Raizada, M

1987-08-01

Exposure of Nostoc muscorum to different concentrations of Ni and Ag brought about reduction in growth, carbon fixation, heterocyst production, and nitrogenase activity and increase in the loss of ions (K+, Na+). In an attempt to ameliorate the toxicity of test metals by ascorbic acid, glutathione, and sulfur-containing amino acids (L-cysteine and L-methionine), it was found that the level of protection by ascorbic acid and glutathione was more for Ag than Ni. However, metal-induced inhibition of growth and carbon fixation was equally ameliorated by methionine. But the level of protection by cysteine was quite different, i.e., 27% for Ni and 22% for Ag. Protection of metal toxicity in N. muscorum by amino acids lends further support to self-detoxifying ability of cyanobacteria because they are known to synthesize all essential amino acids.

The Simplest Flowchart Stating the Mechanisms for Organic Xenobiotics-induced Toxicity: Can it Possibly be Accepted as a "Central Dogma" for Toxic Mechanisms?

Science.gov (United States)

Park, Yeong-Chul; Lee, Sundong; Cho, Myung-Haing

2014-09-01

Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems.

Physico-Chemical Properties of Kaolin-Organic Acid

Directory of Open Access Journals (Sweden)

Yeo S.W.

2017-01-01

Full Text Available Soil with more than 20% of organic content is classified as organic soil in Malaysia. Contents of organic soil consist of different types of organic and inorganic matter. Each type of organic matter has its own characteristic and its effect on the properties of the soil is different. Hence, a good understanding on the effect of specific organic and inorganic matter on the physico-chemical characteristic of organic soils can serve as a guide for predicting the properties of organic soils. The main objective is to unveil the effect of organic acid on the physico-chemical properties of soil. Artificial organic soil (kaolin mixed with organic acid was utilized in order to minimize the geochemical variability of studied soil. The organic acid which consists of humic acid and fulvic acid was extracted from highly humificated plant–based compost. The effect of organic acid on the physico-chemical properties of soil was determined by varying the concentration of organic acid. The specific gravity, Atterberg limits, pH, bulk chemical composition and the functional group of kaolin-organic acid were determined. It was found that the plasticity index, specific gravity and pH value were decreased with lowered concentration of organic acid. However, the liquid limits and plastic limits were found to be increased with the concentration decrement of organic acid. The analysis of XRF on the bulk chemical composition and analysis of FTIR spectra on the functional group of artificial organic soils with different concentration have confirmed little geochemical variability between samples.

Toxicity of copper chelates of azomethines and amino acids for Chlorella pyrenoidosa

Energy Technology Data Exchange (ETDEWEB)

Barashkov, G.K.; Rukhadze, E.G.; Talyzenkova, G.P.

1979-01-01

The authors have attempted to assess the toxicity of copper-containing compounds from the point of view of their interrelationship with the structural characteristics of the chelate compound and the structure of the ligand. The copper chelates of the azomethines tested may be provisionally divided into three types: A - complexes with N-alkly-azomethines; B - complexes with N-aryl-azomethines; C - binuclear complexes. Consideration was also given to chelates with aromatic and heterocyclic amino acids and to heteroligand chelates in which the copper atom coordinates azomethine and an amino acid simultaneously. Toxicity was determined by the method previously described and expressed as a critical concentration (C/sub cr/, mg Cu/liter) and in relative toxicity units (T/sub c/). The compounds investigated were obtained from the interaction between a bidentant ligand of an azomethine or anamino acid and copper acetate in a water-alcohol medium at pH 6-8. Since they are not very soluble in water, true solutions were obtained by using dimethyl sulfoxide.

Ozonides: intermediates in ozone-induced toxicity : a study on their mechanism of toxic action and detoxification by antioxidants

NARCIS (Netherlands)

Hempenius, R.A.

2000-01-01

Ozone is a major constituent of photochemical smog. The toxicity of ozone is well documented and has been related to its strong oxidative potential. The principal target organ for ozone toxicity is the respiratory system. Unsaturated fatty acids, which are present in both the lipids of the

Physicochemical properties and ecotoxicological effects of yttrium oxide nanoparticles in aquatic media: Role of low molecular weight natural organic acids

International Nuclear Information System (INIS)

Zhang, Fan; Wang, Zhuang; Wang, Se; Fang, Hao; Chen, Mindong; Xu, Defu; Tang, Lili; Wang, Degao

2016-01-01

Understanding how engineered nanoparticles (ENPs) interact with natural organic acids is important to ecological risk assessment of ENPs, but this interaction remains poorly studied. Here, we investigate the dispersion stability, ion release, and toxicity of yttrium oxide nanoparticles (nY_2O_3) suspensions after exposure to two low molecular weight natural organic acids (LOAs), namely benzoic acid and gallic acid. We find that in the presence of LOAs the nY_2O_3 suspensions become more stable with surface zeta potential more positive or negative, accompanied by small agglomerated size. LOA interaction with nY_2O_3 is shown to promote the release of dissolved yttrium from the nanoparticles, depending on the concentrations of LOAs. Toxic effects of the nY_2O_3 suspensions incubated with LOAs on Scenedesmus obliquus as a function of their mixture levels show three types of signs: stimulation, inhibition, and alleviation. The mechanism of the effects of LOAs on the nY_2O_3 toxicity may be mainly associated with the degree of agglomeration, particle-induced oxidative stress, and dissolved yttrium. Our results stressed the importance of LOA impacts on the fate and toxicity of ENPs in the aquatic environment. - Highlights: • LOAs significantly increased aqueous stability of nY2O3 in a dose-dependent manner. • The presence of LOAs promoted dissolution of nY2O3 in a dose-dependent manner. • Toxicity of nY2O3 with LOAs to Scenedesmus obliquus varied with mixture levels. • Stimulation, inhibition, and alleviation effects of nY2O3 with LOAs were observed. • Mechanism may be driven by agglomeration, oxidative stress, and dissolved yttrium. - LOAs elevate the dispersion stability of nano-Y_2O_3, promote the release of dissolved yttrium, and alter the algal toxicity of nano-Y_2O_3.

Effects of low-molecular-weight organic acids on the acute lethality, accumulation, and enzyme activity of cadmium in Eisenia fetida in a simulated soil solution.

Science.gov (United States)

Liu, Hai-Long; Wang, Yu-Jun; Xuan, Liang; Dang, Fei; Zhou, Dong-Mei

2017-04-01

In the present study, the effects of low-molecular-weight organic acids (LMWOAs) on the toxicity of cadmium (Cd) to Eisenia fetida were investigated in a simulated soil solution. The LMWOAs protected E. fetida from Cd toxicity, as indicated by the increased median lethal concentration (LC50) values and the increased activity of superoxide dismutase. In addition, Cd concentrations in E. fetida decreased dramatically in the presence of LMWOAs. These results were likely because of the complexation between Cd and LMWOAs, which decreased the bioavailability and consequential toxicity of Cd to E. fetida. Notably, LMWOAs reduced Cd toxicity in decreasing order (ethylenediamine tetraacetic acid [EDTA] > citric acid > oxalic acid > malic acid > acetic acid), which was consistent with the decreasing complexation constants between LMWOAs and Cd. These results advance our understanding of the interactions between Cd and LMWOAs in soil. Environ Toxicol Chem 2017;36:1005-1011. © 2016 SETAC. © 2016 SETAC.

Dataset on usnic acid from Cladonia substellata Vainio (Lichen) schistosomiasis mansoni's vector control and environmental toxicity.

Science.gov (United States)

Andrade de Araújo, Hallysson Douglas; Dos Santos Silva, Luanna Ribeiro; de Siqueira, Williams Nascimento; Martins da Fonseca, Caíque Silveira; da Silva, Nicácio Henrique; de Albuquerque Melo, Ana Maria Mendonça; Barroso Martins, Mônica Cristina; de Menezes Lima, Vera Lúcia

2018-04-01

This text presents complementary data corresponding to schistosomiasis mansoni's vector control and enviromental toxicity using usnic acid. These informations support our research article "Toxicity of Usnic Acid from Cladonia substellata (Lichen) to embryos and adults of Biomphalaria glabrata " by Araújo et al. [1], and focuses on the analysis of the detailed data regarding the different concentrations of Usnic Acid and their efficiency to B. glabrata mortality and non-viability, as also to environmental toxicity, evaluated by A. salina mortality.

The effect of pH on the bioconcentration and toxicity of weak organic electrolytes

DEFF Research Database (Denmark)

Rendal, Cecilie

to the bioconcentration of ionizing organic compounds showed that this fraction cannot safely be overlooked. The work presented in this thesis suggests that the standard test procedures used to test toxicity and bioconcentration are not sufficient to fully illuminate the ecotoxicity of ionizing organic compounds unless......Many of the compounds in use today have ionizing properties. Investigations have shown that around half of the compounds preregistered for REACH and over 70% of all pharmaceuticals are ionizing organic compounds. These compounds may pose a risk when they are released into the environment....... Ionization, however, complicates the environmental risk assessment of these compounds because the uptake processes of the neutral fraction differ from the processes of the ionized fraction. Acids are increasingly neutral at pH levels below the pKa while bases are increasingly neutral at pH levels above the p...

Organic acid enhanced electrodialytic extraction of lead from contaminated soil fines in suspension

DEFF Research Database (Denmark)

Jensen, Pernille Erland; Ahring, Birgitte Kiær; Ottosen, Lisbeth M.

2007-01-01

for decontamination of the sludge was investigated. The ability of 11 organic acids to extract Pb from the fine fraction of contaminated soil (grains soil fines in suspension......The implementation of soil washing technology for the treatment of heavy metal contaminated soils is limited by the toxicity and unwieldiness of the remaining heavy metal contaminated sludge. In this work, the feasibility of combining electrodialytic remediation with heterotrophic leaching...... was tested. Five of the acids showed the ability to extract Ph from the soil fines in excess of the effect caused solely by pH changes. Addition of the acids, however, severely impeded EDR, hence promotion of EDR by combination with heterotrophic leaching was rejected. In contrast, enhancement of EDR...

Granular activated carbon for simultaneous adsorption and biodegradation of toxic oil sands process-affected water organic compounds.

Science.gov (United States)

Islam, Md Shahinoor; Zhang, Yanyan; McPhedran, Kerry N; Liu, Yang; Gamal El-Din, Mohamed

2015-04-01

Naphthenic acids (NAs) released into oil sands process-affected water (OSPW) during bitumen processing in Northern Alberta are problematic for oil sands industries due to their toxicity in the environment and resistance to degradation during conventional wastewater treatment processes. Granular activated carbon (GAC) has shown to be an effective media in removing biopersistent organics from wastewater using a combination of adsorption and biodegradation removal mechanisms. A simultaneous GAC (0.4 g GAC/L) adsorption and biodegradation (combined treatment) study was used for the treatment of raw and ozonated OSPW. After 28 days of batch treatment, classical and oxidized NAs removals for raw OSPW were 93.3% and 73.7%, and for ozonated OSPW were 96.2% and 77.1%, respectively. Synergetic effects of the combined treatment process were observed in removals of COD, the acid extractable fraction, and oxidized NAs, which indicated enhanced biodegradation and bioregeneration in GAC biofilms. A bacteria copy number >10(8) copies/g GAC on GAC surfaces was found using quantitative real time polymerase chain reaction after treatment for both raw and ozonated OSPW. A Microtox(®) acute toxicity test (Vibrio fischeri) showed effective toxicity removal (>95.3%) for the combined treatments. Therefore, the simultaneous GAC adsorption and biodegradation treatment process is a promising technology for the elimination of toxic OSPW NAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Acute toxicity of double-walled carbon nanotubes to three aquatic organisms

CSIR Research Space (South Africa)

Lukhele, LP

2015-01-01

Full Text Available , respectively. In the presence of humic acid high DWCNTs acute toxicity towards D. pulex and P. reticulata was observed but ionic strength led to opposite effect irrespective of DWCNTs form. Both humic acid and ionic strength shielded the P. subcapitata from...

[Toxicity of chongqing acid fogwater on rabbit alveolar macrophages in vitro].

Science.gov (United States)

Shu, W Q; Zhuo, J B

1992-07-01

We collected acid fogwater on a fogday and observed its toxic effects on rabbits' pulmonary alveolar macrophages (AM) in vitro. The fogwater was diluted into 4 concentrations: 1, 1/10, 1/100, and 1/1000 of the original fogwater and the exposure time was 12 hours. The results showed that both the AM's viability and the phagocytic capacity were depressed significantly, but the AM's lysosomal enzyme--acid phosphatase activity was found to be stimulated to increase. All these changes were directly correlated with the degree of pollution of the fogwater. Of these three toxicity indices, the most sensitive one was the change of AM's phagocytic capacity.

Staining of proteins in gels with Coomassie G-250 without organic solvent and acetic acid.

Science.gov (United States)

Lawrence, Ann-Marie; Besir, H Uuml Seyin

2009-08-14

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80 mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staining of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compounds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands.

Protective effect of eicosapentaenoic acid on ouabain toxicity in neonatal rat cardiac myocytes

International Nuclear Information System (INIS)

Hallaq, H.; Leaf, A.; Sellmayer, A.; Smith, T.W.

1990-01-01

Isolated neonatal cardiac myocytes have been utilized as a model for the study of cardiac arrhythmogenic factors. The myocytes respond to the toxic effects of a potent cardiac glycoside, ouabain at 0.1 mM, by an increase in their spontaneous beating rate and a reduction in amplitude of contractions resulting within minutes in a lethal state of contracture. Incubating the isolated myocytes for 3 endash 5 days in culture medium enriched with 5 μM arachidonic acid had no effect on the development of lethal contracture after subsequent exposure to 0.1 mM ouabain. By contrast, incubating the myocytes for 3 endash 5 days with 5 μM eicosapentaenoic acid completely prevented the toxic effects of ouabain at 0.1 mM. No differences in bumetanide-inhibitable 86 Rb flux were observed between the three preparations. However, measurements with fura-2 of cytosolic free calcium levels indicated that control and arachidonic acid-enriched myocytes developed toxic cytosolic calcium concentrations of 845 ± 29 and 757 ± 64 nM, respectively, on exposure to 0.1 mM ouabain, whereas in eicosapentaenoic acid-enriched myocytes, physiologic calcium levels were preserved. Incubating the myocytes with eicosapentaenoic acid for 3 endash 5 days resulted in a small reduction of arachidonic acid and a small but significant increase of eicosapentaenoic acid in membrane phospolipids of the myocytes

The Simplest Flowchart Stating the Mechanisms for Organic Xenobiotics-induced Toxicity: Can it Possibly be Accepted as a “Central Dogma” for Toxic Mechanisms?

Science.gov (United States)

Lee, Sundong; Cho, Myung-Haing

2014-01-01

Xenobiotics causing a variety of toxicity in biological systems could be classified as two types, inorganic and organic chemicals. It is estimated that the organic xenobiotics are responsible for approximately 80~90% of chemical-induced toxicity in human population. In the class for toxicology, we have encountered some difficulties in explaining the mechanisms of toxicity caused especially by organic chemicals. Here, a simple flowchart was introduced for explaining the mechanism of toxicity caused by organic xenobiotics, as the central dogma of molecular biology. This flowchart, referred to as a central dogma, was described based on a view of various aspects as follows: direct-acting chemicals vs. indirect-acting chemicals, cytochrome P450-dependent vs. cytochrome P450-independent biotransformation, reactive intermediates, reactivation, toxicokinetics vs. toxicodynamics, and reversibility vs. irreversibility. Thus, the primary objective of this flowchart is to help better understanding of the organic xenobiotics-induced toxic mechanisms, providing a major pathway for toxicity occurring in biological systems. PMID:25343011

Nickel deficiency disrupts metabolism of ureides, amino acids, and organic acids of young pecan foliage.

Science.gov (United States)

Bai, Cheng; Reilly, Charles C; Wood, Bruce W

2006-02-01

The existence of nickel (Ni) deficiency is becoming increasingly apparent in crops, especially for ureide-transporting woody perennials, but its physiological role is poorly understood. We evaluated the concentrations of ureides, amino acids, and organic acids in photosynthetic foliar tissue from Ni-sufficient (Ni-S) versus Ni-deficient (Ni-D) pecan (Carya illinoinensis [Wangenh.] K. Koch). Foliage of Ni-D pecan seedlings exhibited metabolic disruption of nitrogen metabolism via ureide catabolism, amino acid metabolism, and ornithine cycle intermediates. Disruption of ureide catabolism in Ni-D foliage resulted in accumulation of xanthine, allantoic acid, ureidoglycolate, and citrulline, but total ureides, urea concentration, and urease activity were reduced. Disruption of amino acid metabolism in Ni-D foliage resulted in accumulation of glycine, valine, isoleucine, tyrosine, tryptophan, arginine, and total free amino acids, and lower concentrations of histidine and glutamic acid. Ni deficiency also disrupted the citric acid cycle, the second stage of respiration, where Ni-D foliage contained very low levels of citrate compared to Ni-S foliage. Disruption of carbon metabolism was also via accumulation of lactic and oxalic acids. The results indicate that mouse-ear, a key morphological symptom, is likely linked to the toxic accumulation of oxalic and lactic acids in the rapidly growing tips and margins of leaflets. Our results support the role of Ni as an essential plant nutrient element. The magnitude of metabolic disruption exhibited in Ni-D pecan is evidence of the existence of unidentified physiological roles for Ni in pecan.

Method to prepare essentially organic waste liquids containing radioactive or toxic materials

International Nuclear Information System (INIS)

Baehr, W.; Drobnik, S.H.; Hild, W.; Kroebel, R.; Meyer, A.; Naumann, G.

1976-01-01

Waste solutions occuring in nuclear technology containing radioactive or toxic materials can be solidified by mixing with a polymerisable mixture with subsequent polymerization. An improvement of this method, especially for liquids in which the radioactive components are present as organic compounds is achieved by adding a mixture of at least one monomeric vinyl compound, at least one polyvinyl compound and appropriate catalysts and by polymerizing at temperatures between 15 and 150 0 C. Should the waste liquid contain mineral acid, this is first neutralized by the addition of CaO or MgO. In processing oils or soaps, the addition of swelling agent for polystyrol resins is advantageous. 16 examples illustrate the invention. (UWI) [de

Production of Valuables Organic Acids from Organic Wastes with Hydrothermal Treatment Process

Directory of Open Access Journals (Sweden)

Muhammad Faisal

2009-06-01

Full Text Available This article reports production of valuables organic acids from the hydrothermal treatment of representative organic wastes and compounds (i. e. domestic sludge, proteinaceous, cellulosic and plastic wastes with or without oxidant (H2O2. Organic acids such as acetic, formic, propionic, succinic and lactic acids were obtained in significant amounts. At 623 K (16.5 MPa, acetic acid of about 26 mg/g-dry waste fish entrails was obtained. This increased to 42 mg/g dry waste fish entrails in the presence of H2O2. Experiments on glucose to represent cellulosic wastes were also carried out, getting acetic acid of about 29 mg/g-glucose. The study was extended to terephthalic acid and glyceraldehyde, reaction intermediates of hydrothermal treatment of PET plastic wastes and glucose, respectively. Studies on temperature dependence of formation of organic acids showed thermal stability of acetic acid, whereas, formic acid decomposed readily under hydrothermal conditions. In general, results demonstrated that the presence of oxidants favored formation of organic acids with acetic acid being the major product. Keywords: hydrothermal treatment, organic acids, organic wastes, oxidant, supercritical water oxidation

Triphenyl phosphate-induced developmental toxicity in zebrafish: Potential role of the retinoic acid receptor

Energy Technology Data Exchange (ETDEWEB)

Isales, Gregory M.; Hipszer, Rachel A.; Raftery, Tara D. [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States); Chen, Albert; Stapleton, Heather M. [Division of Environmental Sciences and Policy, Nicholas School of the Environment, Duke University, Durham, NC (United States); Volz, David C., E-mail: volz@mailbox.sc.edu [Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC (United States)

2015-04-15

Highlights: • Triphenyl phosphate-induced toxicity in zebrafish embryos is enhanced in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate uptake or metabolism within zebrafish embryos is not altered in the presence of a retinoic acid receptor antagonist. • Triphenyl phosphate decreases expression of cytochrome P450 26a1 in zebrafish embryos. • Triphenyl phosphate inhibits retinoic acid-induced activation of human retinoic acid receptors. - Abstract: Using zebrafish as a model, we previously reported that developmental exposure to triphenyl phosphate (TPP) – a high-production volume organophosphate-based flame retardant – results in dioxin-like cardiac looping impairments that are independent of the aryl hydrocarbon receptor. Using a pharmacologic approach, the objective of this study was to investigate the potential role of retinoic acid receptor (RAR) – a nuclear receptor that regulates vertebrate heart morphogenesis – in mediating TPP-induced developmental toxicity in zebrafish. We first revealed that static exposure of zebrafish from 5–72 h post-fertilization (hpf) to TPP in the presence of non-toxic concentrations of an RAR antagonist (BMS493) significantly enhanced TPP-induced toxicity (relative to TPP alone), even though identical non-toxic BMS493 concentrations mitigated retinoic acid (RA)-induced toxicity. BMS493-mediated enhancement of TPP toxicity was not a result of differential TPP uptake or metabolism, as internal embryonic doses of TPP and diphenyl phosphate (DPP) – a primary TPP metabolite – were not different in the presence or absence of BMS493. Using real-time PCR, we then quantified the relative change in expression of cytochrome P450 26a1 (cyp26a1) – a major target gene for RA-induced RAR activation in zebrafish – and found that RA and TPP exposure resulted in a ∼5-fold increase and decrease in cyp26a1 expression, respectively, relative to vehicle-exposed embryos. To address whether TPP may

Understanding the Strategies to Overcome Phosphorus–Deficiency and Aluminum–Toxicity by Ryegrass Endophytic and Rhizosphere Phosphobacteria

Directory of Open Access Journals (Sweden)

Patricio J. Barra

2018-06-01

Full Text Available Phosphobacteria, secreting organic acids and phosphatases, usually favor plant performance in acidic soils by increasing phosphorus (P availability and aluminum (Al complexing. However, it is not well-known how P-deficiency and Al-toxicity affect the phosphobacteria physiology. Since P and Al problems often co-occur in acidic soils, we have therefore proposed the evaluation of the single and combined effects of P-deficiency and Al-toxicity on growth, organic acids secretion, malate dehydrogenase (mdh gene expression, and phosphatase activity of five Al-tolerant phosphobacteria previously isolated from ryegrass. These phosphobacteria were identified as Klebsiella sp. RC3, Stenotrophomona sp. RC5, Klebsiella sp. RCJ4, Serratia sp. RCJ6, and Enterobacter sp. RJAL6. The strains were cultivated in mineral media modified to obtain (i high P in absence of Al–toxicity, (ii high P in presence of Al–toxicity, (iii low P in absence of Al–toxicity, and (iv low P in presence of Al–toxicity. High and low P were obtained by adding KH2PO4 at final concentration of 1.4 and 0.05 mM, respectively. To avoid Al precipitation, AlCl3 × 6H2O was previously complexed to citric acid (sole carbon source in concentrations of 10 mM. The secreted organic acids were identified and quantified by HPLC, relative mdh gene expression was determined by qRT-PCR and phosphatase activity was colorimetrically determined using p-nitrophenyl phosphate as substrate. Our results revealed that although a higher secretion of all organic acids was achieved under P–deficiency, the patterns of organic acids secretion were variable and dependent on treatment and strain. The organic acid secretion is exacerbated when Al was added into media, particularly in the form of malic and citric acid. The mdh gene expression was significantly up–regulated by the strains RC3, RC5, and RCJ6 under P–deficiency and Al–toxicity. In general, Al–tolerant phosphobacteria under P deficiency

Neuroprotective effect of creatine against propionic acid toxicity in ...

African Journals Online (AJOL)

edoja

2013-07-31

Jul 31, 2013 ... Full Length Research Paper. Neuroprotective effect of creatine against propionic acid toxicity in neuroblastoma SH-SY5Y cells in culture. Afaf El-Ansary*, Ghada Abu-Shmais and Abeer Al-Dbass. Biochemistry Department, College of Science, King Saud University, P.O. Box 22452, Zip code 11495, Riyadh, ...

Energy densification of biomass-derived organic acids

Energy Technology Data Exchange (ETDEWEB)

Wheeler, M. Clayton; van Walsum, G. Peter; Schwartz, Thomas J.; van Heiningen, Adriaan

2013-01-29

A process for upgrading an organic acid includes neutralizing the organic acid to form a salt and thermally decomposing the resulting salt to form an energy densified product. In certain embodiments, the organic acid is levulinic acid. The process may further include upgrading the energy densified product by conversion to alcohol and subsequent dehydration.

Subchronic toxicity evaluation of γ-aminobutyric acid (GABA) in rats.

Science.gov (United States)

Takeshima, Kazuhito; Yamatsu, Atsushi; Yamashita, Yusuke; Watabe, Kazuya; Horie, Noriko; Masuda, Kazuyuki; Kim, Mujo

2014-06-01

γ-Aminobutyric acid (GABA) is an amino acid compound contained in vegetables such as tomatoes and also widely distributed in mammals. GABA acts as an inhibitory neurotransmitter and promotes parasympathetic activity to provide several beneficial effects, for instance, relaxation, anti-stress, and insomnia. GABA, produced via a fermentation process, has been available as a functional food ingredient. As part of a program to assess its safety, GABA was administered by oral gavage at doses of 500, 1250, and 2500mg/kg body weight to groups of 10 male and 10 female Sprague-Dawley rats for 13weeks. Treatment was not associated with the test substance-related mortality and appeared to be well tolerated. There were no toxicologically and statistically significant changes in urinalysis, hematology, clinical chemistry parameters, and in necropsy findings. A few statistically significant changes in food consumption and body weights were noted in the male groups while any significant changes were not noted in female groups. There was no effect of treatment on organ weights or on the results of the histopathological examinations. The results of toxicity evaluation support the safety use of GABA and the potential use as a functional food ingredient. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of keratin on heavy metal chelation and toxicity to aquatic organisms

Energy Technology Data Exchange (ETDEWEB)

Coello, W.F.; Khan, M.A.Q. [Univ. of Illinois, Chicago, IL (United States). Dept. of Biological Sciences

1998-12-31

The presence of fresh scales and human hair in water can reduce the toxicity of lead nitrate at and above 6 ppb to fish. This ability is lost on drying and storage, but can be restored if dried hair or scales are treated with a solution of amino acids. The chelation ability of keratin in amino acid-treated scales or hair is retained for months on dry storage. Addition of these hair and/or scales to solutions of lead nitrate, mercuric chloride and a mixture of both, and cupric sulfate reduced the toxicity of these solutions to Daphnia magna and Dreissena polymorpha (zebra mussels). Toxicity of 10 ppm solutions of salts of 27 different metals to daphnids was similarly reduced after filtration through scales or hair. A mixture of a 2 ppb concentration of each of these 27 metals also became nonlethal to daphnids in the presence of, or filtration through, treated scales or hair. 0.25 g of treated hair or scale can be used indefinitely, again and again, to remove the mixture of these 27 metals from their fresh solution in 1 L water if the keratin is frequently rinsed with 0.1% nitric acid to remove the bound metals. The keratin in scales, this, may be the most important ectodermal secretion in absorbing metals from polluted environments and in providing protection against their toxic levels.

Is ozonation environmentally benign for reverse osmosis concentrate treatment? Four-level analysis on toxicity reduction based on organic matter fractionation.

Science.gov (United States)

Weng, Jingxia; Jia, Huichao; Wu, Bing; Pan, Bingcai

2018-01-01

Ozonation is a promising option to treat reverse osmosis concentrate (ROC). However, a systematic understanding and assessment of ozonation on toxicity reduction is insufficient. In this study, ROC sampled from a typical industrial park wastewater treatment plant of China was fractionated into hydrophobic acid (HOA), hydrophobic base (HOB), hydrophobic neutral (HON), and hydrophilic fraction (HI). Systematic bioassays covering bacteria, algae, fish, and human cell lines were conducted to reveal the role of ozonation in toxicity variation of the four ROC fractions. HOA in the raw ROC exhibited the highest toxicity, followed by HON and HI. Ozonation significantly reduced total organic carbon (TOC) and UV 254 values in HOA, HON, and HI and their toxicity except in HOB. Correlation analysis indicated that chemical data (TOC and UV 254 ) of HOA and HON correlated well with their toxicities; however, poor correlations were observed for HOB and HI, suggesting that a battery of toxicity assays is necessary. This study indicates that TOC reduction during ozonation could not fully reflect the toxicity issue, and toxicity assessment is required in conjunction with the chemical data to evaluate the effectiveness of ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessment of toxicity on chelating agent DTPA (diethylenetriaminepentaacetic acid)

International Nuclear Information System (INIS)

Fukuda, Satoshi

1989-01-01

DTPA (diethylenetriaminepentaacetic acid) is a very important chelating agent to decorporate the radionuclides such as plutonium and americium from human body. However, before DTPA will be administered to humans, the toxicity should be clarified. This report described the summary on data of DTPA toxicities obtained from animal experiments and assessment on the safety for humans, based on the results that compared their data among animal species. In short, Ca-DTPA is less toxic than Zn-DTPA when it is injected intravenously, while Zn-DTPA is less toxic than Ca-DTPA when it is administered orally. Both DTPAs acted on the serum calcium metabolism and induced the functional damages of cardiovascular system. Particularly, it is stressed that Zn-DTPA by intravenous injection occurred the heart failure, increases of blood pressure and pulse with hypocalcemia in even normal rats and beagle dogs. Other side effects by both DTPAs were also observed in the intestine, liver, kidney and bone. It is estimated that there are almost no species differences on DTPA toxicity between animals and humans. As a result, it is concluded that DTPA should be used very carefully for humans, with reference to the results obtained from animal experiments. (author) 61 refs

Assessment of toxicity on chelating agent DTPA (diethylenetriaminepentaacetic acid)

Energy Technology Data Exchange (ETDEWEB)

Fukuda, Satoshi (National Inst. of Radiological Sciences, Chiba (Japan))

1989-09-01

DTPA (diethylenetriaminepentaacetic acid) is a very important chelating agent to decorporate the radionuclides such as plutonium and americium from human body. However, before DTPA will be administered to humans, the toxicity should be clarified. This report described the summary on data of DTPA toxicities obtained from animal experiments and assessment on the safety for humans, based on the results that compared their data among animal species. In short, Ca-DTPA is less toxic than Zn-DTPA when it is injected intravenously, while Zn-DTPA is less toxic than Ca-DTPA when it is administered orally. Both DTPAs acted on the serum calcium metabolism and induced the functional damages of cardiovascular system. Particularly, it is stressed that Zn-DTPA by intravenous injection occurred the heart failure, increases of blood pressure and pulse with hypocalcemia in even normal rats and beagle dogs. Other side effects by both DTPAs were also observed in the intestine, liver, kidney and bone. It is estimated that there are almost no species differences on DTPA toxicity between animals and humans. As a result, it is concluded that DTPA should be used very carefully for humans, with reference to the results obtained from animal experiments. (author) 61 refs.

Radioisotopic methods - determination of action of toxic chemicals to food - digestion organs

International Nuclear Information System (INIS)

Saitmuratova, O.H.; Tursunov, E.A.

2004-01-01

Full text: It is known that poison chemicals used for agriculture enter in an organism of human and animal by various ways and affect key processes in cells and tissues. These processes are investigated insufficiently, nevertheless, investigating actions of chemicals on bodies and tissues it, is possible to define a degree of its toxicity. In the present work influence of defoliant drop and insecticide buldok on protein synthetic ability (PSA) of cells of digestive bodies (a liver, a stomach and duodenal gut) is investigated. Experiments carried out on white not purebred rats - males in weight 160-180 g, which entered drop in doze of 1/5 IC 50 5350 mg/kg, buldok 1/5 IC 50 400 mg/kg and 14 C-glutamine acid with the general activity 1 mk Curie (2.2*106 imp/min) in one hour up to slaughter. A control animal in parallel entered a physiological solution. In animals hammered in one hour and investigated inclusion 14 C- glutamine acids in structure of synthesized proteins of a liver, a stomach and duodenal gut. Action of preparations checked in 1, 24 and 72 hours after introduction. As have shown the received data drop suppresses PSA in cells of a liver on 14 % and 45 % in 24 and 72 hours accordingly; in a stomach - on 32 % and 34 %; in duodenal gut - on 39 % and 48 %. PSA it is more suppressed in a stomach. Further process is gradually restored in all bodies. Buldok in the same terms suppresses PSA in a liver on 4 % and 25 %; in a stomach of 4 % and 16 % and in duodenal gut on the contrary are raised with formation of protein on 27 %. The next day there is restoration PSA in all investigated bodies. From the received data it is visible, that defoliant drop as well as insecticide buldok influence on PSA cells, but action of drop is stronger, than buldok. It will be coordinated to earlier received data on change of morphological structures under influence of these pesticides. Though drop and buldok differ on dynamics of action on PSA digestive bodies, they are not strongly

EMISSIONS OF ORGANIC AIR TOXICS FROM OPEN ...

Science.gov (United States)

A detailed literature search was performed to collect and collate available data reporting emissions of toxic organic substances into the air from open burning sources. Availability of data varied according to the source and the class of air toxics of interest. Volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) data were available for many of the sources. Data on semivolatile organic compounds (SVOCs) that are not PAHs were available for several sources. Carbonyl and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofuran (PCDD/F) data were available for only a few sources. There were several sources for which no emissions data were available at all. Several observations were made including: 1) Biomass open burning sources typically emitted less VOCs than open burning sources with anthropogenic fuels on a mass emitted per mass burned basis, particularly those where polymers were concerned; 2) Biomass open burning sources typically emitted less SVOCs and PAHs than anthropogenic sources on a mass emitted per mass burned basis. Burning pools of crude oil and diesel fuel produced significant amounts of PAHs relative to other types of open burning. PAH emissions were highest when combustion of polymers was taking place; and 3) Based on very limited data, biomass open burning sources typically produced higher levels of carbonyls than anthropogenic sources on a mass emitted per mass burned basis, probably due to oxygenated structures r

Toxicity of selected organic chemicals to the earthworm Eisenia fetida

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.F.; Loehr, R.C.; Malecki, M.R.; Milligan, D.L.; Durkin, P.R.

A number of methods recently have been developed to biologically evaluate the impact of man's activities on soil ecosystems. Two test methods, the 2-d contact test and the 14-d artificial soil test, were used to evaluate the impact of six major classes of organic chemicals on the earthworm Eisenia fetida (Savigny). Of the organic chemicals tested, phenols and amines were the most toxic to the worms, followed in descending order of toxicity by the substituted aromatics, halogenated aliphatics, polycyclic aromatic hydrocarbons, and phthalates. No relationship was found between earthworm toxicity as determined by the contact test and rat, Rattus norvegicus Berkenhout and mouse, Mus musculus L. LD/sub 50/ values. The physicochemical parameters of water solubility, vapor pressure, and octanol/water partition coefficient for the chemicals tested in the contact test did not show a significant relationship to the E. fetida LC/sub 50/ values. These studies indicate that: (i) earthworms can be a suitable biomonitoring tool to assist in measuring the impact of organic chemicals in wastes added to soils and (ii) contact and artificial soil tests can be useful in measuring biological impacts.

Building a developmental toxicity ontology.

Science.gov (United States)

Baker, Nancy; Boobis, Alan; Burgoon, Lyle; Carney, Edward; Currie, Richard; Fritsche, Ellen; Knudsen, Thomas; Laffont, Madeleine; Piersma, Aldert H; Poole, Alan; Schneider, Steffen; Daston, George

2018-04-03

As more information is generated about modes of action for developmental toxicity and more data are generated using high-throughput and high-content technologies, it is becoming necessary to organize that information. This report discussed the need for a systematic representation of knowledge about developmental toxicity (i.e., an ontology) and proposes a method to build one based on knowledge of developmental biology and mode of action/ adverse outcome pathways in developmental toxicity. This report is the result of a consensus working group developing a plan to create an ontology for developmental toxicity that spans multiple levels of biological organization. This report provide a description of some of the challenges in building a developmental toxicity ontology and outlines a proposed methodology to meet those challenges. As the ontology is built on currently available web-based resources, a review of these resources is provided. Case studies on one of the most well-understood morphogens and developmental toxicants, retinoic acid, are presented as examples of how such an ontology might be developed. This report outlines an approach to construct a developmental toxicity ontology. Such an ontology will facilitate computer-based prediction of substances likely to induce human developmental toxicity. © 2018 Wiley Periodicals, Inc.

Nickel Deficiency Disrupts Metabolism of Ureides, Amino Acids, and Organic Acids of Young Pecan Foliage[OA

Science.gov (United States)

Bai, Cheng; Reilly, Charles C.; Wood, Bruce W.

2006-01-01

The existence of nickel (Ni) deficiency is becoming increasingly apparent in crops, especially for ureide-transporting woody perennials, but its physiological role is poorly understood. We evaluated the concentrations of ureides, amino acids, and organic acids in photosynthetic foliar tissue from Ni-sufficient (Ni-S) versus Ni-deficient (Ni-D) pecan (Carya illinoinensis [Wangenh.] K. Koch). Foliage of Ni-D pecan seedlings exhibited metabolic disruption of nitrogen metabolism via ureide catabolism, amino acid metabolism, and ornithine cycle intermediates. Disruption of ureide catabolism in Ni-D foliage resulted in accumulation of xanthine, allantoic acid, ureidoglycolate, and citrulline, but total ureides, urea concentration, and urease activity were reduced. Disruption of amino acid metabolism in Ni-D foliage resulted in accumulation of glycine, valine, isoleucine, tyrosine, tryptophan, arginine, and total free amino acids, and lower concentrations of histidine and glutamic acid. Ni deficiency also disrupted the citric acid cycle, the second stage of respiration, where Ni-D foliage contained very low levels of citrate compared to Ni-S foliage. Disruption of carbon metabolism was also via accumulation of lactic and oxalic acids. The results indicate that mouse-ear, a key morphological symptom, is likely linked to the toxic accumulation of oxalic and lactic acids in the rapidly growing tips and margins of leaflets. Our results support the role of Ni as an essential plant nutrient element. The magnitude of metabolic disruption exhibited in Ni-D pecan is evidence of the existence of unidentified physiological roles for Ni in pecan. PMID:16415214

Plant responses to metal toxicity

Energy Technology Data Exchange (ETDEWEB)

Briat, J.F. [Montpellier-2 Univ., 34 (France). Biochimie et physiologie moleculaire des plantes, CNRS, URA 2133; Lebrun, M. [Montpellier-2 Univ., 34 (France). Biochimie et physiologie vegetale appliquee

1999-01-01

Increased metal concentration in the soils, up to toxic levels, is becoming an important environmental problem. Safety rule evolution will require solutions in order to cope with food safety rules, and to freeze metal leakage from heavily metal-poisoned soils, such as those from industrial fallows. In this context, plants could serve to develop bio-assays in order to promote new standards, more realistic than the mass of a given metal per kg of soil, that does not consider the metal bio-disponibility. Plants could also be used for phyto-extraction and/or phyto-stabilization. To reach these objectives, a genetic approach could be useful to generate metal-tolerant plants with enough biomass. In this work is more particularly studied the plant responses to metal toxicity. Metal toxicity for living organisms involves oxidative and /or genotoxic mechanisms. Plant protection against metal toxicity occurs, at least in part, through control of root metal uptake and of long distance metal transport. Inside cells, proteins such as ferritins and metallothioneins, and glutathione-derived peptides named phyto-chelatins, participate in excess metal storage and detoxification. Low molecular weight organic molecules, mainly organic acids and amino acids and their derivatives, also play an important role in plant metal homeostasis. When these systems are overloaded, oxidative stress defense mechanisms are activated. Molecular and cellular knowledge of these processes will be necessary to improve plant metal resistance. Occurrence of naturally tolerant plants which hyper accumulate metals provides helpful tools for this research. (authors) 130 refs.

Roles of Organic Acid Anion Secretion in Aluminium Tolerance of Higher Plants

Science.gov (United States)

Yang, Lin-Tong; Qi, Yi-Ping; Jiang, Huan-Xin; Chen, Li-Song

2013-01-01

Approximately 30% of the world's total land area and over 50% of the world's potential arable lands are acidic. Furthermore, the acidity of the soils is gradually increasing as a result of the environmental problems including some farming practices and acid rain. At mildly acidic or neutral soils, aluminium(Al) occurs primarily as insoluble deposits and is essentially biologically inactive. However, in many acidic soils throughout the tropics and subtropics, Al toxicity is a major factor limiting crop productivity. The Al-induced secretion of organic acid (OA) anions, mainly citrate, oxalate, and malate, from roots is the best documented mechanism of Al tolerance in higher plants. Increasing evidence shows that the Al-induced secretion of OA anions may be related to the following several factors, including (a) anion channels or transporters, (b) internal concentrations of OA anions in plant tissues, (d) temperature, (e) root plasma membrane (PM) H+-ATPase, (f) magnesium (Mg), and (e) phosphorus (P). Genetically modified plants and cells with higher Al tolerance by overexpressing genes for the secretion and the biosynthesis of OA anions have been obtained. In addition, some aspects needed to be further studied are also discussed. PMID:23509687

Nanoparticles modified with multiple organic acids

Science.gov (United States)

Cook, Ronald Lee (Inventor); Luebben, Silvia DeVito (Inventor); Myers, Andrew William (Inventor); Smith, Bryan Matthew (Inventor); Elliott, Brian John (Inventor); Kreutzer, Cory (Inventor); Wilson, Carolina (Inventor); Meiser, Manfred (Inventor)

2007-01-01

Surface-modified nanoparticles of boehmite, and methods for preparing the same. Aluminum oxyhydroxide nanoparticles are surface modified by reaction with selected amounts of organic acids. In particular, the nanoparticle surface is modified by reactions with two or more different carboxylic acids, at least one of which is an organic carboxylic acid. The product is a surface modified boehmite nanoparticle that has an inorganic aluminum oxyhydroxide core, or part aluminum oxyhydroxide core and a surface-bonded organic shell. Organic carboxylic acids of this invention contain at least one carboxylic acid group and one carbon-hydrogen bond. One embodiment of this invention provides boehmite nanoparticles that have been surface modified with two or more acids one of which additional carries at least one reactive functional group. Another embodiment of this invention provides boehmite nanoparticles that have been surface modified with multiple acids one of which has molecular weight or average molecular weight greater than or equal to 500 Daltons. Yet, another embodiment of this invention provides boehmite nanoparticles that are surface modified with two or more acids one of which is hydrophobic in nature and has solubility in water of less than 15 by weight. The products of the methods of this invention have specific useful properties when used in mixture with liquids, as filler in solids, or as stand-alone entities.

Nanoparticles modified with multiple organic acids

Science.gov (United States)

Cook, Ronald Lee; Luebben, Silvia DeVito; Myers, Andrew William; Smith, Bryan Matthew; Elliott, Brian John; Kreutzer, Cory; Wilson, Carolina; Meiser, Manfred

2007-07-17

Surface-modified nanoparticles of boehmite, and methods for preparing the same. Aluminum oxyhydroxide nanoparticles are surface modified by reaction with selected amounts of organic acids. In particular, the nanoparticle surface is modified by reactions with two or more different carboxylic acids, at least one of which is an organic carboxylic acid. The product is a surface modified boehmite nanoparticle that has an inorganic aluminum oxyhydroxide core, or part aluminum oxyhydroxide core and a surface-bonded organic shell. Organic carboxylic acids of this invention contain at least one carboxylic acid group and one carbon-hydrogen bond. One embodiment of this invention provides boehmite nanoparticles that have been surface modified with two or more acids one of which additional carries at least one reactive functional group. Another embodiment of this invention provides boehmite nanoparticles that have been surface modified with multiple acids one of which has molecular weight or average molecular weight greater than or equal to 500 Daltons. Yet, another embodiment of this invention provides boehmite nanoparticles that are surface modified with two or more acids one of which is hydrophobic in nature and has solubility in water of less than 15 by weight. The products of the methods of this invention have specific useful properties when used in mixture with liquids, as filler in solids, or as stand-alone entities.

Biobased organic acids production by metabolically engineered microorganisms

DEFF Research Database (Denmark)

Chen, Yun; Nielsen, Jens

2016-01-01

Bio-based production of organic acids via microbial fermentation has been traditionally used in food industry. With the recent desire to develop more sustainable bioprocesses for production of fuels, chemicals and materials, the market for microbial production of organic acids has been further...... expanded as organic acids constitute a key group among top building block chemicals that can be produced from renewable resources. Here we review the current status for production of citric acid and lactic acid, and we highlight the use of modern metabolic engineering technologies to develop high...... performance microbes for production of succinic acid and 3-hydroxypropionic acid. Also, the key limitations and challenges in microbial organic acids production are discussed...

Subchronic toxicity and immunotoxicity of MeO-PEG-poly(D,L-lactic-co-glycolic acid)-PEG-OMe triblock copolymer nanoparticles delivered intravenously into rats

International Nuclear Information System (INIS)

Liao, Longfei; Zhang, Mengtian; Liu, Huan; Zhang, Xuanmiao; Xie, Zhaolu; Zhang, Zhirong; Gong, Tao; Sun, Xun

2014-01-01

Although monomethoxy(polyethyleneglycol)-poly (D,L-lactic-co-glycolic acid)-monomethoxy (PELGE) nanoparticles have been widely studied as a drug delivery system, little is known about their toxicity in vivo. Here we examined the subchronic toxicity and immunotoxicity of different doses of PELGE nanoparticles with diameters of 50 and 200 nm (PELGE50 and PELGE200) in rats. Neither size of PELGE nanoparticles showed obvious subchronic toxic effects during 28 d of continuous intravenous administration based on clinical observation, body weight, hematology parameters and histopathology analysis. PELGE200 nanoparticles showed no overt signs of immunotoxicity based on organ coefficients, histopathology analysis, immunoglobulin levels, blood lymphocyte subpopulations and splenocyte cytokines. Conversely, PELGE50 nanoparticles were associated with an increased organ coefficient and histopathological changes in the spleen, increased serum IgM and IgG levels, alterations in blood lymphocyte subpopulations and enhanced expression of spleen interferon-γ. Taken together, these results suggest that PELGE nanoparticles show low subchronic toxicity but substantial immunotoxicity, which depends strongly on particle size. These findings will be useful for safe application of PELGE nanoparticles in drug delivery systems. (papers)

Subchronic toxicity and immunotoxicity of MeO-PEG-poly(D,L-lactic-co-glycolic acid)-PEG-OMe triblock copolymer nanoparticles delivered intravenously into rats

Science.gov (United States)

Liao, Longfei; Zhang, Mengtian; Liu, Huan; Zhang, Xuanmiao; Xie, Zhaolu; Zhang, Zhirong; Gong, Tao; Sun, Xun

2014-06-01

Although monomethoxy(polyethyleneglycol)-poly (D,L-lactic-co-glycolic acid)-monomethoxy (PELGE) nanoparticles have been widely studied as a drug delivery system, little is known about their toxicity in vivo. Here we examined the subchronic toxicity and immunotoxicity of different doses of PELGE nanoparticles with diameters of 50 and 200 nm (PELGE50 and PELGE200) in rats. Neither size of PELGE nanoparticles showed obvious subchronic toxic effects during 28 d of continuous intravenous administration based on clinical observation, body weight, hematology parameters and histopathology analysis. PELGE200 nanoparticles showed no overt signs of immunotoxicity based on organ coefficients, histopathology analysis, immunoglobulin levels, blood lymphocyte subpopulations and splenocyte cytokines. Conversely, PELGE50 nanoparticles were associated with an increased organ coefficient and histopathological changes in the spleen, increased serum IgM and IgG levels, alterations in blood lymphocyte subpopulations and enhanced expression of spleen interferon-γ. Taken together, these results suggest that PELGE nanoparticles show low subchronic toxicity but substantial immunotoxicity, which depends strongly on particle size. These findings will be useful for safe application of PELGE nanoparticles in drug delivery systems.

Elucidating mechanisms of toxic action of dissolved organic chemicals in oil sands process-affected water (OSPW).

Science.gov (United States)

Morandi, Garrett D; Wiseman, Steve B; Guan, Miao; Zhang, Xiaowei W; Martin, Jonathan W; Giesy, John P

2017-11-01

Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface-mining oil sands industry in Alberta, Canada, and is acutely and chronically toxic to aquatic organisms. It is known that dissolved organic compounds in OSPW are responsible for most toxic effects, but knowledge of the specific mechanism(s) of toxicity, is limited. Using bioassay-based effects-directed analysis, the dissolved organic fraction of OSPW has previously been fractionated, ultimately producing refined samples of dissolved organic chemicals in OSPW, each with distinct chemical profiles. Using the Escherichia coli K-12 strain MG1655 gene reporter live cell array, the present study investigated relationships between toxic potencies of each fraction, expression of genes and characterization of chemicals in each of five acutely toxic and one non-toxic extract of OSPW derived by use of effects-directed analysis. Effects on expressions of genes related to response to oxidative stress, protein stress and DNA damage were indicative of exposure to acutely toxic extracts of OSPW. Additionally, six genes were uniquely responsive to acutely toxic extracts of OSPW. Evidence presented supports a role for sulphur- and nitrogen-containing chemical classes in the toxicity of extracts of OSPW. Copyright © 2017 Elsevier Ltd. All rights reserved.

Linkage of genomic biomarkers to whole organism endpoints in a Toxicity Identification Evaluation (TIE).

Science.gov (United States)

Aquatic organisms are exposed to many toxic chemicals and interpreting the cause and effect relationships between occurrence and impairment is difficult. Toxicity Identification Evaluation (TIE) provides a systematic approach for identifying responsible toxicants. TIE relies on ...

Copper Metal-Organic Framework Nanoparticles Stabilized with Folic Acid Improve Wound Healing in Diabetes.

Science.gov (United States)

Xiao, Jisheng; Zhu, Yunxiao; Huddleston, Samantha; Li, Peng; Xiao, Baixue; Farha, Omar K; Ameer, Guillermo A

2018-02-27

The successful treatment of chronic nonhealing wounds requires strategies that promote angiogenesis, collagen deposition, and re-epithelialization of the wound. Copper ions have been reported to stimulate angiogenesis; however, several applications of copper salts or oxides to the wound bed are required, leading to variable outcomes and raising toxicity concerns. We hypothesized that copper-based metal-organic framework nanoparticles (Cu-MOF NPs), referred to as HKUST-1, which are rapidly degraded in protein solutions, can be modified to slowly release Cu 2+ , resulting in reduced toxicity and improved wound healing rates. Folic acid was added during HKUST-1 synthesis to generate folic-acid-modified HKUST-1 (F-HKUST-1). The effect of folic acid incorporation on NP stability, size, hydrophobicity, surface area, and copper ion release profile was measured. In addition, cytotoxicity and in vitro cell migration processes due to F-HKUST-1 and HKUST-1 were evaluated. Wound closure rates were assessed using the splinted excisional dermal wound model in diabetic mice. The incorporation of folic acid into HKUST-1 enabled the slow release of copper ions, which reduced cytotoxicity and enhanced cell migration in vitro. In vivo, F-HKUST-1 induced angiogenesis, promoted collagen deposition and re-epithelialization, and increased wound closure rates. These results demonstrate that folic acid incorporation into HKUST-1 NPs is a simple, safe, and promising approach to control Cu 2+ release, thus enabling the direct application of Cu-MOF NPs to wounds.

Effect of Toxicants on Fatty Acid Metabolism in HepG2 Cells

Directory of Open Access Journals (Sweden)

David Grünig

2018-04-01

Full Text Available Impairment of hepatic fatty acid metabolism can lead to liver steatosis and injury. Testing drugs for interference with hepatic fatty acid metabolism is therefore important. To find out whether HepG2 cells are suitable for this purpose, we investigated the effect of three established fatty acid metabolism inhibitors and of three test compounds on triglyceride accumulation, palmitate metabolism, the acylcarnitine pool and dicarboxylic acid accumulation in the cell supernatant and on ApoB-100 excretion in HepG2 cells. The three established inhibitors [etomoxir, methylenecyclopropylacetic acid (MCPA, and 4-bromocrotonic acid (4-BCA] depleted mitochondrial ATP at lower concentrations than cytotoxicity occurred, suggesting mitochondrial toxicity. They inhibited palmitate metabolism at similar or lower concentrations than ATP depletion, and 4-BCA was associated with cellular fat accumulation. They caused specific changes in the acylcarnitine pattern and etomoxir an increase of thapsic (C18 dicarboxylic acid in the cell supernatant, and did not interfere with ApoB-100 excretion (marker of VLDL export. The three test compounds (amiodarone, tamoxifen, and the cannabinoid WIN 55,212-2 depleted the cellular ATP content at lower concentrations than cytotoxicity occurred. They all caused cellular fat accumulation and inhibited palmitate metabolism at similar or higher concentrations than ATP depletion. They suppressed medium-chain acylcarnitines in the cell supernatant and amiodarone and tamoxifen impaired thapsic acid production. Tamoxifen and WIN 55,212-2 decreased cellular ApoB-100 excretion. In conclusion, the established inhibitors of fatty acid metabolism caused the expected effects in HepG2 cells. HepG cells proved to be useful for the detection of drug-associated toxicities on hepatocellular fatty acid metabolism.

Different low-molecular-mass organic acids specifically control leaching of arsenic and lead from contaminated soil.

Science.gov (United States)

Ash, Christopher; Tejnecký, Václav; Borůvka, Luboš; Drábek, Ondřej

2016-04-01

Low-molecular-mass organic acids (LMMOA) are of key importance for mobilisation and fate of metals in soil, by functioning as ligands that increase the amount of dissolved metal in solution or by dissociation of metal binding minerals. Column leaching experiments were performed on soil polluted with As and Pb, in order to determine the specificity of LMMOA related release for individual elements, at varying organic acid concentrations. Acetic, citric and oxalic acids were applied in 12h leaching experiments over a concentration range (0.5-25 mM) to soil samples that represent organic and mineral horizons. The leaching of As followed the order: oxalic>citric>acetic acid in both soils. Arsenic leaching was attributed primarily to ligand-enhanced dissolution of mineral oxides followed by As released into solution, as shown by significant correlation between oxalic and citric acids and content of Al and Fe in leaching solutions. Results suggest that subsurface mineral soil layers are more vulnerable to As toxicity. Leaching of Pb from both soils followed the order: citric>oxalic>acetic acid. Mineral soil samples were shown to be more susceptible to leaching of Pb than samples characterised by a high content of organic matter. The leaching efficiency of citric acid was attributed to formation of stable complexes with Pb ions, which other acids are not capable of. Results obtained in the study are evidence that the extent of As and Pb leaching in contaminated surface and subsurface soil depends significantly on the types of carboxylic acid involved. The implications of the type of acid and the specific element that can be mobilised become increasingly significant where LMMOA concentrations are highest, such as in rhizosphere soil. Copyright © 2016 Elsevier B.V. All rights reserved.

Nanocellulose coated with various free fatty acids can adsorb fumonisin B1, and decrease its toxicity.

Science.gov (United States)

Zadeh, Mohammad Hossein Balal; Shahdadi, Hossein

2015-10-01

The aim of this study was to evaluate the adsorption and biological properties of nanocellulose coated with free fatty acids (NCCFFAs). At first, nanocellulose was synthesized by acid hydrolysis, and then separately coated with different free fatty acids (FFAs), including lauric acid, alpha linoleic acid, oleic acid, and palmitic acid. Next, the serial concentrations of NCCFFAs (1, 10, 100, and 1000 μg/mL) was separately added to fumonisin B1 (FB1) at 1000 μg/mL, and separately incubated at 37 °C for 1, 2, and 3h. Then, the percentage of adsorption was calculated. In the next experiment, the viability of mouse liver cells was measured when they exposed to serial concentrations of NCCFFAs, FFAs, and FB1. This study showed that the increase of incubation time and concentration of NCCFFAs led to increase of FB1 adsorption. Although FFAs and NCCFFAs had no remarkable toxicity, the high toxicity was observed for FB1. Importantly, the toxicity of FB1 was highly decreased, when incubated together with FFAs or NCCFFAs. These novel adsorbents, NCCFFAs, can be used together with different foodstuffs to remove FB1. Copyright © 2015 Elsevier B.V. All rights reserved.

Acid digestion of organic liquids

International Nuclear Information System (INIS)

Partridge, J.A.; Bosuego, G.P.

1980-10-01

Laboratory studies on the destruction of liquid organic wastes by acid digestion are discussed. A variety of liquid waste types was tested, including those encountered in the nuclear industry as well as some organic liquids representative of non-nuclear industrial wastes. The liquids tested were vacuum pump oil, tri-n-butyl phosphate (TBP), normal paraffin hydrocarbon solvent (NPH), a mixture of 30 vol% TBP in NPH, carbon tetrachloride (CCl 4 ), trichloroethane, toluene, hexone (methyl isobutyl ketone), a mixture of hexone and NPH, polychlorobiphenyl (PCB), isopropanol, normal-decane, and two waste organic solutions from Hanford radioactive waste tanks. The tests demonstrated that several types of organic liquids can be destroyed by the acid digestion process. 8 figures, 19 tables

Comparative toxicity of ten organic chemicals to four earthworm species

Energy Technology Data Exchange (ETDEWEB)

Neuhauser, E.F.; Durkin, P.R.; Malecki, M.R.; Anatra, M.

1986-01-01

Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were the most toxic chemicals tested, followed by the amine, substituted benzenes, halogenated aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and phthalate as the least toxic chemical tested. Correlations among species within each type of test for a given chemical were extremely high, suggesting that the selection of earthworm test species does not markedly affect the assessment of a chemical's toxicity. The correlation between the two tests was low for all test species. The contact test LC50 for a given chemical cannot be directly correlated to an artificial soil test LC50 for the same earthworm species.

Modeling time-dependent toxicity to aquatic organisms from pulsed exposure of PAHs in urban road runoff

International Nuclear Information System (INIS)

Zhang Wei; Ye Youbin; Tong Yindong; Ou Langbo; Hu Dan; Wang Xuejun

2011-01-01

Understanding of the magnitude of urban runoff toxicity to aquatic organisms is important for effective management of runoff quality. In this paper, the aquatic toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban road runoff was evaluated through a damage assessment model. Mortality probability of the organisms representative in aquatic environment was calculated using the monitored PAHs concentration in road runoff. The result showed that the toxicity of runoff in spring was higher than those in summer. Analysis of the time-dependent toxicity of series of runoff water samples illustrated that the toxicity of runoff water in the final phase of a runoff event may be as high as those in the initial phase. Therefore, the storm runoff treatment systems or strategies designed for capture and treatment of the initial portion of runoff may be inappropriate for control of runoff toxicity. - Research highlights: → Toxicity resulting from realistic exposure patterns of urban runoff is evaluated. → Toxicity of runoff water in the final phase is as high as the initial phase. → Treatment of the initial runoff portion is inappropriate to abate runoff toxicity. - Toxicity to aquatic organisms after sequential pulsed exposure to PAHs in urban road runoff is evaluated.

Preparation of fulvic acid and low-molecular organic acids by oxidation of weathered coal humic acid

Energy Technology Data Exchange (ETDEWEB)

Shinozuka, T.; Ito, A.; Sasaki, O.; Yazawa, Y.; Yamaguchi, T. [Chiba Institute of Technolgy, Chiba (Japan). Dept. of Industrial Chemistry

2002-07-01

Weathered coal contains much humic acid and a little fulvic acid. Therefore, the production of fulvic acid, the most valuable humic substance because of its water-solubility, was examined by ozone and hydrogen peroxide oxidation of humic acid extracted form Xinjiang (China) weathered coal. The resulting products of the oxidation were water soluble fulvic acid and organic acids, mainly formic acid and oxalic acid. The product yield of fulvic acid was 20 (C%) and that of organic acids were 39 (C%) for formic and acid 13 (C%) for oxalic acid. The formed fulvic acid showed a higher content of oxygen and carboxyl groups, than those of the extracted one from the original weathered coal.

Development of Low-Toxicity Wastewater Stabilization for Spacecraft Water Recovery Systems

Science.gov (United States)

Adam, Niklas; Mitchell, Julie; Pickering, Karen; Carrier, Chris; Vega, Letty; Muirhead, Dean

2014-01-01

Wastewater stabilization was an essential component of the spacecraft water cycle. The purpose of stabilizing wastewater was two-fold. First, stabilization prevents the breakdown of urea into ammonia, a toxic gas at high concentrations. Second, it prevents the growth of microorganisms, thereby mitigating hardware and water quality issues due to due biofilm and planktonic growth. Current stabilization techniques involve oxidizers and strong acids (pH=2) such as chromic and sulfuric acid, which are highly toxic and pose a risk to crew health. The purpose of this effort was to explore less toxic stabilization techniques, such as food-grade and commercial care preservatives. Additionally, certain preservatives were tested in the presence of a low-toxicity organic acid. Triplicate 300-mL volumes of urine were dosed with a predetermined quantity of stabilizer and stored for two weeks. During that time, pH, total organic carbon (TOC), ammonia, and turbidity were monitored. Those preservatives that showed the lowest visible microbial growth and stable pH were further tested in a six-month stability study. The results of the six-month study are also included in this paper.

Manganese toxicity effects on nodulation and nitrogen fixation of beans (Phaseolus vulgaris L. ), in acid soils

Energy Technology Data Exchange (ETDEWEB)

Doebereiner, J

1966-02-01

Three greenhouse experiments were conducted to study manganese toxicity effects on the nitrogen fixing symbiosis of beans (Phaseolus vulgaris). Addition of 40 ppm of manganese to two acid soils affected nodulation and nitrogen fixation. Dependent on the Rhizobion strain either nodule numbers or efficiency in nitrogen fixation were reduced; the efficiency of one Rhizobium-host combination was more affected than another. Under less severe conditions of manganese toxicity, reduction of nodule numbers or of efficiency in nitrogen fixation could be compensated by an increase of nodule size. In the absence of manganese toxicity nodulation and nitrogen fixation of beans were abundant in a soil with pH 4.4. Naturally occurring manganese toxicity in a gray hydromorphic soil was eliminated by liming. The total nitrogen content of bean plants which were dependent on symbiotic nitrogen fixation decreased linearly with the logarithm of the manganese concentration in the plants. This did not happen when the plants were grown with mineral nitrogen. The role of manganese toxicity in the well known sensitivity to acid soil conditions of certain legumes and the importance of selection of manganese tolerant Rhizobium strains for the inoculation of beans in acid tropical soils, are discussed. 25 references, 1 figure, 6 tables.

The Protective effect of Ellagic acid on rats’ ovarian fetus toxicity induced by cyclophosphamide

Directory of Open Access Journals (Sweden)

M Mousavi M

2015-10-01

Full Text Available Background & aim: Cyclophosphamide, an alkylating agent used in the treatment of cancer that has many side effects on different organs, including the gonads .The purpose of this study was to investigate the effects of an antioxidant Ellagic acid on cyclophosphamide -induced toxicity in rat fetal ovarian tissue. Methods: Forty two pregnant  female Wistar rats weighing 250-200 gr were randomly divided into seven groups.The first, second, third, fourth, fifth and sixth 5 mg/ kg cyclophosphamide on days 1, 13 and 18 were given intraperitoneal remote pregnancy .The fourth, fifth and sixth groups hour after receiving cyclophosphamide, Ellagic acid (10 mg/kg has received in the course of pregnancy.Control groups and seven group (normal during pregnancy daily orally received 0.5 mL of saline. After postpartum, Neonatal rats were anesthetized with ether. Animals were dissects, then Ovaries were removed and transferred to 10% formalin solution. After tissue processing, tissue sections were prepared and H&E stained.Data were analyzed by SPSSsoftware and One- way ANOVA test. Results: The groups that were exposed to cyclophosphamide ovarian mean of diameter, primordial follicle diameter and number of follicular cell of primordialin control group compared to ellagic acid treatments showed a significant decrease. Conclusion: The results showed that Ellagic acid due to its antioxidant properties could reduce the harmful effects caused by cyclophosphamide in the fetal ovary.

Response of nitrogen metabolism to boron toxicity in tomato plants.

Science.gov (United States)

Cervilla, L M; Blasco, B; Ríos, J J; Rosales, M A; Rubio-Wilhelmi, M M; Sánchez-Rodríguez, E; Romero, L; Ruiz, J M

2009-09-01

Boron (B) toxicity has become important in areas close to the Mediterranean Sea where intensive agriculture has been developed. The objective of this research was to study the effects of B toxicity (0.5 mM and 2.0 mM B) on nitrogen (N) assimilation of two tomato cultivars that are often used in these areas. Leaf biomass, relative leaf growth rate (RGR(L)), concentration of B, nitrate (NO(3) (-)), ammonium (NH(4) (+)), organic N, amino acids and soluble proteins, as well as nitrate reductase (NR), nitrite reductase (NiR), glutamine synthase (GS), glutamate synthetase (GOGAT) and glutamate dehydrogenase (GDH) activities were analysed in leaves. Boron toxicity significantly decreased leaf biomass, RGR(L), organic N, soluble proteins, and NR and NiR activities. The lowest NO(3) (-) and NH(4) (+) concentration in leaves was recorded when plants were supplied with 2.0 mM B in the root medium. Total B, amino acids, activities of GS, GOGAT and GDH increased under B toxicity. Data from the present study prove that B toxicity causes inhibition of NO(3) (-) reduction and increases NH(4) (+) assimilation in tomato plants.

Diversity and dynamics of rhizobial populations in acidic soils with aluminum and manganese toxicities in forest zones

Directory of Open Access Journals (Sweden)

Linda Manet

2016-12-01

Full Text Available Soil acidity in the humid forest zones of Cameroon is one of the major constraints to agricultural productivity. This study was carried out to assess the rhizobial communities of two acidic soils; with aluminum toxicity (Nkoemvone and manganese toxicity (Nkolbisson for their potential to improve soil fertility in Cameroon. These two soils were used to inoculate to the host plants cowpea and siratro. At harvest, 120 rhizobacterial isolates were extracted from the nodules of these two hosts and subjected to morphological characterization. Twenty isolates per site were selected and analyzed for their 16S rDNA genetic profile following restrictions with endonucleases of PCR products and electrophoresis. The restriction patterns of the 16S rDNA of the 40 isolates showed 12 different profiles. Eight occurred in both types of soils, where as 4 were specific to the manganese-toxic-acidic soil. While the Al toxicity reduced the nodulation and growth of both plants, the Mn toxicity mostly affect the cowpea. This study ascertained the distribution of rhizobia based on soil characteristics. Further molecular analyses would allow the identification of the isolates recovered as well as their phylogenetical relationships.

Mixture toxicity of the antiviral drug Tamiflu (oseltamivir ethylester) and its active metabolite oseltamivir acid

Energy Technology Data Exchange (ETDEWEB)

Escher, Beate I., E-mail: b.escher@uq.edu.au [University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd, Brisbane, Qld 4108 (Australia); Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf (Switzerland); Bramaz, Nadine; Lienert, Judit; Neuwoehner, Judith [Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf (Switzerland); Straub, Juerg Oliver [F.Hoffmann-La Roche Ltd, Corporate Safety, Health and Environmental Protection, 4070 Basel (Switzerland)

2010-02-18

Tamiflu (oseltamivir ethylester) is an antiviral agent for the treatment of influenza A and B. The pro-drug Tamiflu is converted in the human body to the pharmacologically active metabolite, oseltamivir acid, with a yield of 75%. Oseltamivir acid is indirectly photodegradable and slowly biodegradable in sewage works and sediment/water systems. A previous environmental risk assessment has concluded that there is no bioaccumulation potential of either of the compounds. However, little was known about the ecotoxicity of the metabolite. Ester hydrolysis typically reduces the hydrophobicity and thus the toxicity of a compound. In this case, a zwitterionic, but overall neutral species is formed from the charged parent compound. If the speciation and predicted partitioning into biological membranes is considered, the metabolite may have a relevant contribution to the overall toxicity. These theoretical considerations triggered a study to investigate the toxicity of oseltamivir acid (OA), alone and in binary mixtures with its parent compound oseltamivir ethylester (OE). OE and OA were found to be baseline toxicants in the bioluminescence inhibition test with Vibrio fischeri. Their mixture effect lay between predictions for concentration addition and independent action for the mixture ratio excreted in urine and nine additional mixture ratios of OE and OA. In contrast, OE was an order of magnitude more toxic than OA towards algae, with a more pronounced effect when the direct inhibition of photosystem II was used as toxicity endpoint opposed to the 24 h growth rate endpoint. The binary mixtures in this assay yielded experimental mixture effects that agreed with predictions for independent action. This is consistent with the finding that OE exhibits slightly enhanced toxicity, while OA acts as baseline toxicant. Therefore, with respect to mixture classification, the two compounds can be considered as acting according to different modes of toxic action, although there are

Toxic epidermal necrolysis due to concomitant use of lamotrigine and valproic acid

Directory of Open Access Journals (Sweden)

Sukhjot Kaur

2013-01-01

Full Text Available Anti-epileptic drugs can be associated with a wide spectrum of cutaneous adverse reactions ranging from simple maculopapular rashes to more severe and life threatening reactions like Stevens-Johnson syndrome and toxic epidermal necrolysis. These rashes are well documented with older antiepileptic drugs like phenytoin, phenobarbitone and carbamazapine. Lamotrigine is a newer, unrelated antiepileptic drug that causes skin rashes in 3-10% of new users. Higher starting dose or rapid escalation, concurrent treatment with valproic acid, and a previous history of a rash with other antiepileptic drugs are well recognized risk factors for lamotrigine related serious rashes. We report two patients with toxic epidermal necrolysis, resulting from concomitant use of lamotrigine and valproic acid. It is emphasized that clinicians adhere to the recommended dosage guidelines and adopt a slow dose titration when initiating treatment with lamotrigine.

STUDY OF ORGANIC ACIDS IN ALMOND LEAVES

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Lenchyk L.V.

2015-05-01

Full Text Available Introduction. Almond (Amygdalus communis is a stone fruit, from the Rosaceae family, closest to the peach. It is spread throughout the entire Mediterranean region and afterwards to the Southwestern USA, Northern Africa, Turkey, Iran, Australia and South Africa. It is sensitive to wet conditions, and therefore is not grown in wet climates. Iran is located in the semi-arid region of the world. Because of its special tolerance to water stress, almond is one of the main agricultural products in rainfed condition in Iran. Almond leaves have been investigated for their phenolic content and antioxidant activity. It was found that total antioxidant activity and phenolic compounds exhibited variations according to season, plant organ (leaf and stem and variety. Analysis of previous research on almonds focused on investigating compounds mostly in seeds and phenolic compounds in leaves, but organic acids in leaves have not been studied. Aim of this study was investigation of organic acids in leaves of almond variety which is distributed in Razavi Khorasan province of Iran. Materials and Methods. In August 2012 almond leaves were collected in Iran, dried and grinded. The study of qualitative composition and quantitative determination of carboxylic acids in almond leaves was carried out by gas chromatography with mass spectrometric detection. For determination organic acids content, to 50 mg of dried plant material in 2 ml vial internal standard (50 μg of tridecane in hexane was added and filled up with 1.0 ml of methylating agent (14 % BCl3 in methanol, Supelco 3-3033. The mixture was kept in a sealed vial during 8 hours at 65 °C. At this time fatty oil was fully extracted, and hydrolyzed into its constituent fatty acids and their methylation was done. At the same time free organic and phenolcarbonic acids were methylated too. The reaction mixture was poured from the plant material sediment and was diluted with 1 ml of distilled water. To extract methyl

Toxicity of natural mixtures of organic pollutants in temperate and polar marine phytoplankton

KAUST Repository

Echeveste, Pedro

2016-07-26

Semivolatile and persistent organic pollutants (POPs) undergo atmospheric transport before being deposited to the oceans, where they partition to phytoplankton organic matter. The goal of this study was to determine the toxicity of naturally occurring complex mixtures of organic pollutants to temperate and polar phytoplankton communities from the Mediterranean Sea, the North East (NE) Atlantic, and Southern Oceans. The cell abundance of the different phytoplankton groups, chlorophyll a concentrations, viability of the cells, and growth and decay constants were monitored in response to addition of a range of concentrations of mixtures of organic pollutants obtained from seawater extracts. Almost all of the phytoplankton groups were significantly affected by the complex mixtures of non-polar and polar organic pollutants, with toxicity being greater for these mixtures than for single POPs or simple POP mixtures. Cocktails\\' toxicity arose at concentrations as low as tenfold the field oceanic levels, probably due to a higher chemical activity of the mixture than of simple POPs mixtures. Overall, smaller cells were the most affected, although Mediterranean picophytoplankton was significantly more tolerant to non-polar POPs than picophytoplankton from the Atlantic Ocean or the Bellingshausen Sea microphytoplankton. © 2016 Elsevier B.V.

Effects of the organic acids produced by a lactic acid bacterium in Apis mellifera colony development, Nosema ceranae control and fumagillin efficiency.

Science.gov (United States)

Maggi, Matías; Negri, Pedro; Plischuk, Santiago; Szawarski, Nicolás; De Piano, Fiorella; De Feudis, Leonardo; Eguaras, Martín; Audisio, Carina

2013-12-27

The European honey bee Apis mellifera is known to be affected by many parasites and pathogens that have great impact over the insect development. Among parasites affecting bee health, Nosema ceranae is one of the main biotic factors affecting colony populations. As honey bee populations decline, interest in pathogenic and mutualistic relationships between bees and microorganisms has increased. The main goal of the current study was to assess the effect of the oral administration of the metabolites produced by Lactobacillus johnsonii CRL1647 (mainly organic acids) supplemented in syrup, on: (I) N. ceranae sporulation dynamics before and after fumagillin application, and (II) performance of A. mellifera colonies. Different experiments were conducted to evaluate the effects of these bacterial metabolites on bees: in vitro administration revealed no toxic effects against bees. Colonies fed with the lactic acids incremented their beehive population and also the amount of fat bodies per bee. Finally, the organic acids reduced the intensity of the pathogen after the second application of treatment as well as enhanced the fumagillin efficiency. This study provides important information for the development of new control substances against nosemosis. Copyright © 2013 Elsevier B.V. All rights reserved.

Organic anion transporter (Slc22a) family members as mediators of toxicity

International Nuclear Information System (INIS)

Sweet, Douglas H.

2005-01-01

Exposure of the body to toxic organic anions is unavoidable and occurs from both intentional and unintentional sources. Many hormones, neurotransmitters, and waste products of cellular metabolism, or their metabolites, are organic anions. The same is true for a wide variety of medications, herbicides, pesticides, plant and animal toxins, and industrial chemicals and solvents. Rapid and efficient elimination of these substances is often the body's best defense for limiting both systemic exposure and the duration of their pharmacological or toxicological effects. For organic anions, active transepithelial transport across the renal proximal tubule followed by elimination via the urine is a major pathway in this detoxification process. Accordingly, a large number of organic anion transport proteins belonging to several different gene families have been identified and found to be expressed in the proximal nephron. The function of these transporters, in combination with the high volume of renal blood flow, predisposes the kidney to increased toxic susceptibility. Understanding how the kidney mediates the transport of organic anions is integral to achieving desired therapeutic outcomes in response to drug interactions and chemical exposures, to understanding the progression of some disease states, and to predicting the influence of genetic variation upon these processes. This review will focus on the organic anion transporter (OAT) family and discuss the known members, their mechanisms of action, subcellular localization, and current evidence implicating their function as a determinant of the toxicity of certain endogenous and xenobiotic agents

Modeling the influence of organic acids on soil weathering

Science.gov (United States)

Lawrence, Corey R.; Harden, Jennifer W.; Maher, Kate

2014-01-01

Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

Acidic organic compounds in beverage, food, and feed production.

Science.gov (United States)

Quitmann, Hendrich; Fan, Rong; Czermak, Peter

2014-01-01

Organic acids and their derivatives are frequently used in beverage, food, and feed production. Acidic additives may act as buffers to regulate acidity, antioxidants, preservatives, flavor enhancers, and sequestrants. Beneficial effects on animal health and growth performance have been observed when using acidic substances as feed additives. Organic acids could be classified in groups according to their chemical structure. Each group of organic acids has its own specific properties and is used for different applications. Organic acids with low molecular weight (e.g. acetic acid, lactic acid, and citric acid), which are part of the primary metabolism, are often produced by fermentation. Others are produced more economically by chemical synthesis based on petrochemical raw materials on an industrial scale (e.g. formic acid, propionic and benzoic acid). Biotechnology-based production is of interest due to legislation, consumer demand for natural ingredients, and increasing environmental awareness. In the United States, for example, biocatalytically produced esters for food applications can be labeled as "natural," whereas identical conventional acid catalyst-based molecules cannot. Natural esters command a price several times that of non-natural esters. Biotechnological routes need to be optimized regarding raw materials and yield, microorganisms, and recovery methods. New bioprocesses are being developed for organic acids, which are at this time commercially produced by chemical synthesis. Moreover, new organic acids that could be produced with biotechnological methods are under investigation for food applications.

Toxic corneal epitheliopathy after intravitreal methotrexate and its treatment with oral folic acid.

Science.gov (United States)

Gorovoy, Ian; Prechanond, Tidarat; Abia, Maravillas; Afshar, Armin R; Stewart, Jay M

2013-08-01

To determine whether oral folic acid can ameliorate an iatrogenic, visually significant corneal epitheliopathy, which commonly occurs with intravitreal injections of methotrexate for the treatment of intraocular lymphoma. We report 2 cases of visually significant corneal epitheliopathy occurring after intravitreal injections of methotrexate for intraocular lymphoma. The first patient did not receive any treatment for the corneal disease, and the second patient with bilateral intraocular lymphoma received 1 mg of oral folic acid daily, a commonly used dosage for patients on systemic methotrexate. In the first patient without treatment, there was a complete regression of the corneal epithelial disease only when the frequency of intravitreal methotrexate was reduced from weekly to monthly as per a commonly used dosage regimen for methotrexate. In the second patient, the corneal disease improved 80% within 1 week of initiating oral folic acid for her eye already experiencing severe epitheliopathy during her weekly dosing regimen of methotrexate and also had significantly decreased epithelial disease in her second eye that started weekly intravitreal methotrexate several weeks after beginning oral folic acid. Currently, oral folic acid supplements are recommended for patients using systemic methotrexate to minimize drug toxicity. We suggest a similar use in patients undergoing intravitreal methotrexate injections to decrease toxic effects on the corneal epithelium.

Effect of the waste products storage on the environmental pollution by toxic organic compounds

Directory of Open Access Journals (Sweden)

Aleksandra Lewkiewicz-Małysa

2005-11-01

Full Text Available A permanent deposition of industrial wastes is a method of its neutralization. A storage yard for toxic materials must meet specific site and construction conditions. The storage place region of toxic organic waste materials has to be monitored. The environmental impact of this waste on the groundwater quality, especially the migration of persistent organic pollutants, was discussed on the example of a chemical plant.

Acute toxicity assessment of perfluorinated carboxylic acids towards the Baltic microalgae.

Science.gov (United States)

Latała, Adam; Nędzi, Marcin; Stepnowski, Piotr

2009-09-01

The presence of high-energy carbon-fluorine bonds in perfluoro compounds lends them great stability and causes them to be environmentally persistent. Relatively little is known about the acute toxicity of perfluorinated carboxylic acids (PFCAs) to ecotoxicological markers such as aquatic plants and animals. This study tested the toxicity of these compounds to the green alga Chlorella vulgaris, the diatom Skeletonema marinoi and the blue-green alga Geitlerinema amphibium, which are species representative of the algal flora of the Baltic Sea. The EC(50) values obtained range from 0.28 mM to 12.84 mM. A distinct relationship between hydrophobicity and toxicity is demonstrated. For every extra perfluoromethylene group in the alkyl chain, the toxicity increases twofold. LogEC(50) values are very well correlated linearly with both the number of carbon atoms in the perfluoroalkyl chain and the partition coefficients. The results also indicate that there are clear differences between the responses of particular taxonomic groups of algae: blue-green algae and diatoms are far more sensitive to PFCAs than green algae, probably because of differences in cell wall structure.

Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

Energy Technology Data Exchange (ETDEWEB)

Comber, S.D.W. [WRc-NSF, Henley Road, Medmenham, Marlow, Buckinghamshire, SL7 2HD (United Kingdom)]. E-mail: sean.comber@atkinsglobal.com; Conrad, A.U. [Weinberg Group, Blue Tower, Box 16, B-1050 Brussels (Belgium); Hoess, S. [ECOSSA, Thierschstrasser 43, 80538, Muenchen (Germany); Webb, S. [CEFIC, Ave E. Van Nieuwenhuyse 4, B-1160 Brussels (Belgium); Marshall, S. [Unilever Research, Environment Centre, Bebington, Wirral, Merseyside, L63 3JW (United Kingdom)

2006-11-15

The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment.

Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

International Nuclear Information System (INIS)

Comber, S.D.W.; Conrad, A.U.; Hoess, S.; Webb, S.; Marshall, S.

2006-01-01

The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment

Simultaneous analysis of small organic acids and humic acids using high performance size exclusion chromatography

NARCIS (Netherlands)

Qin, X.P.; Liu, F.; Wang, G.C.; Weng, L.P.

2012-01-01

An accurate and fast method for simultaneous determination of small organic acids and much larger humic acids was developed using high performance size exclusion chromatography. Two small organic acids, i.e. salicylic acid and 2,3-dihydroxybenzoic acid, and one purified humic acid material were used

Effect of organic acids on shrimp pathogen, Vibrio harveyi.

Science.gov (United States)

Mine, Saori; Boopathy, Raj

2011-07-01

Shrimp farming accounts for more than 40% of the world shrimp production. Luminous vibriosis is a shrimp disease that causes major economic losses in the shrimp industry as a result of massive shrimp kills due to infection. Some farms in the South Asia use antibiotics to control Vibrio harveyi, a responsible pathogen for luminous vibriosis. However, the antibiotic-resistant strain was found recently in many shrimp farms, which makes it necessary to develop alternative pathogen control methods. Short-chain fatty acids are metabolic products of organisms, and they have been used as food preservatives for a long time. Organic acids are also commonly added in feeds in animal husbandry, but not in aquaculture. In this study, growth inhibitory effects of short-chain fatty acids, namely formic acid, acetic acid, propionic acid, and butyric acid, on V. harveyi were investigated. Among four acids, formic acid showed the strongest inhibitory effect followed by acetic acid, propionic acid, and butyric acid. The minimum inhibitory concentration (MIC) of 0.035% formic acid suppressed growth of V. harveyi. The major inhibitory mechanism seems to be the pH effect of organic acids. The effective concentration 50 (EC50) values at 96 h inoculation for all organic acids were determined to be 0.023, 0.041, 0.03, and 0.066% for formic, acetic, propionic, and butyric acid, respectively. The laboratory study results are encouraging to formulate shrimp feeds with organic acids to control vibrio infection in shrimp aquaculture farms.

Research of nickel nanoparticles toxicity with use of Aquatic Organisms

International Nuclear Information System (INIS)

Morgaleva, T; Morgalev, Yu; Gosteva, I; Morgalev, S

2015-01-01

The effect of nanoparticles with the particle size Δ 50 =5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Chlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)C 20 is determined for all the organisms used in bioassays. L(E)C 50 is estimated for Paramecium caudatum (L(E)C 50 = 0.0049 mg/l), for Chlorella vulgaris Beijer (L(E)C 50 = 0.529 mg/l), for Daphnia m. S (L(E)C 50 > 100 mg/l) and for fish Danio rerio (L(E)C 50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances. (paper)

Research of nickel nanoparticles toxicity with use of Aquatic Organisms

Science.gov (United States)

Morgaleva, T.; Morgalev, Yu; Gosteva, I.; Morgalev, S.

2015-11-01

The effect of nanoparticles with the particle size Δ50=5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Chlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)C20 is determined for all the organisms used in bioassays. L(E)C50 is estimated for Paramecium caudatum (L(E)C50 = 0.0049 mg/l), for Chlorella vulgaris Beijer (L(E)C50 = 0.529 mg/l), for Daphnia m. S (L(E)C50 > 100 mg/l) and for fish Danio rerio (L(E)C50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances.

Breaking Bad Delirium: Methamphetamine and Boric Acid Toxicity with Hallucinations and Pseudosepsis.

Science.gov (United States)

Johnson, Kayla; Stollings, Joanna L; Ely, E Wesley

2017-02-01

A 30-year-old patient presented with hallucinations and profound shock. He was initially misdiagnosed as having severe sepsis; once ingestions were considered, he was diagnosed as potentially having arsenic toxicity. The clinical story reveals many instructional lessons that could aid in the evaluation and management of future patients. This man presented with large amounts of blue crystals around his nose and lips from inhaling and eating boric acid (an ant poison) so he could, as he put it, kill the ants "pouring into my mouth and nose and up into my brain." His profound pseudosepsis and sustained delirium were induced by co-ingestion of methamphetamine and a large quantity of boric acid. Delirium is a form of acute brain dysfunction that often is multifactorial in critical illness and, when seen in septic shock, is associated with prolonged mechanical ventilation, increased length of hospital stay, medical costs, higher mortality, and long-term cognitive impairment resembling dementia. Pseudosepsis is a noninfectious condition most commonly seen with ingestions such as salicylate (aspirin) toxicity. This report emphasizes the need to recognize agents that contain boric acid as an etiology of unexplained delirium and profound shock.

Toxicity of carbon nanotubes to freshwater aquatic invertebrates

Science.gov (United States)

Mwangi, Joseph N.; Wang, Ning; Ingersoll, Christopher G.; Hardesty, Doug K.; Brunson, Eric L.; Li, Hao; Deng, Baolin

2012-01-01

Carbon nanotubes (CNTs) are hydrophobic in nature and thus tend to accumulate in sediments if released into aquatic environments. As part of our overall effort to examine the toxicity of carbon-based nanomaterials to sediment-dwelling invertebrates, we have evaluated the toxicity of different types of CNTs in 14-d water-only exposures to an amphipod (Hyalella azteca), a midge (Chironomus dilutus), an oligochaete (Lumbriculus variegatus), and a mussel (Villosa iris) in advance of conducting whole-sediment toxicity tests with CNTs. The results of these toxicity tests conducted with CNTs added to water showed that 1.00g/L (dry wt) of commercial sources of CNTs significantly reduced the survival or growth of the invertebrates. Toxicity was influenced by the type and source of the CNTs, by whether the materials were precleaned by acid, by whether sonication was used to disperse the materials, and by species of the test organisms. Light and electron microscope imaging of the surviving test organisms showed the presence of CNTs in the gut as well as on the outer surface of the test organisms, although no evidence was observed to show penetration of CNTs through cell membranes. The present study demonstrated that both the metals solubilized from CNTs such as nickel and the "metal-free" CNTs contributed to the toxicity.

Application of TIE's in assessing toxicity associated with oil sands process waters

International Nuclear Information System (INIS)

MacKinnon, M.

1998-01-01

The hot water digestion process which separates bitumen from oil sands produces large volumes of process-affected waters which are extremely toxic to aquatic organisms. At Syncrude Canada's northeastern Alberta plant, the toxic waters are contained on the site and none are discharged. Organic acids, hydrocarbons and salts are leached into the tailings waters. A toxicity identification evaluation (TIE) test was used to confirm the main contributors to the acute toxicity in these waters. A battery bioassay approach as well as field and laboratory testing was used to understand the source, pathway and duration of the toxicity. Bioassays helped in developing ways in which to mitigate toxicity issues in both reclamation and operational waters. It was demonstrated that natural bioremediation of process-affected waters can reduce acute and chronic toxicity. The long term reclamation impacts of these waters has yet to be determined

Toxicity of organic supplies for the egg parasitoid Telenomus podisi

Directory of Open Access Journals (Sweden)

Débora Mello da Silva

2014-01-01

Full Text Available Toxicity (dosage per hectare of: 1 Baculovirus anticarsia 140x109 cpi; 2 Bacillus thuringiensis 16.8g; 3 Azadirachtin-A, azadirachtin-B, nimbina and salamina 9.6 ppm; 4 Rotenoids 4 liters; 5 Nitrogen 1.3%, phosphorus 3.0% and total organic carbon 8.0% 3 liters; 6 Sodium silicate 2% 4 liters; 7 Copper 7% + calcium 3.3% 1.8 liters; 8 Sulfur 20% + quicklime 10% 1.8 liters; 9 Chlorpyrifos 384g; 10 Distilled H2O (control were evaluated for pupae and adults of Telenomus podisi. Treatments from 1 to 8 were in general harmless (class 1 to both pupae and adults of T. podisi. Among them, only treatment 5 and 7 presented slightly toxic to the parasitoid with a reduction in parasitism 5 days after F1 parasitoid emergence. Differently, the chlorpyrifos was classified as slightly harmful (class 2 or moderately harmful (class 3. Therefore, the use of the tested organic agricultural supplies in the production of organic soybean is viable, without impairing the natural biological control allowed by this egg parasitoid. Chlorpyrifos use, on the other hand, is not allowed in organic soybean, but even on convention crop production, could whenever possible, be replaced by other products more compatible with T. podisi preservation.

Evaluation of the treatment efficiencies of paper mill whitewaters in terms of organic composition and toxicity

International Nuclear Information System (INIS)

Latorre, Anna; Malmqvist, Asa; Lacorte, Silvia; Welander, Thomas; Barcelo, Damia

2007-01-01

The efficiency of several lab scale treatments (aerobic, anaerobic and ozone or combination of these) was evaluated using two packaging board mill whitewaters. The effect of the different treatments on the elimination of the organic load, the chemical oxygen demand (COD) and the toxicity was tested as well as the relationship between these parameters. Biocides, phenolic compounds, surfactants, plasticiziers and wood extractives were identified in untreated and treated whitewaters by liquid chromatography coupled with mass spectrometry (LC-MS) or gas chromatography coupled with mass spectrometry (GC-MS). A strong dependency on the water type and treatment efficiency was observed, being the combination of anaerobic and aerobic treatments the best option to reduce the organic contaminants in these waters, although in some cases, the toxicity did not decrease. However, ozone as post-treatment permitted a further reduction of organic compounds, toxicity and COD. - Aerobic and anaerobic treatments remove organic compounds in paper mill effluents but toxicity remains

Toxicity, Bioaccumulation and Biotransformation of Silver Nanoparticles in Marine Organisms

Science.gov (United States)

The toxicity, bioaccumulation and biotransformation of citrate and polyvinylpyrrolidone (PVP) capped silver nanoparticles (NPs) (AgNP-citrate and AgNP-PVP) and titanium dioxide (TiO2) NPs in marine organisms via marine sediment exposure were investigated. Results from 7-d sedimen...

An indicator for effects of organic toxicants on lotic invertebrate communities: Independence of confounding environmental factors over an extensive river continuum

International Nuclear Information System (INIS)

Beketov, Mikhail A.; Liess, Matthias

2008-01-01

Distinguishing between effects of natural and anthropogenic environmental factors on ecosystems is a fundamental problem in environmental science. In river systems the longitudinal gradient of environmental factors is one of the most relevant sources of dissimilarity between communities that could be confounded with anthropogenic disturbances. To test the hypothesis that in macroinvertebrate communities the distribution of species' sensitivity to organic toxicants is independent of natural longitudinal factors, but depends on contamination with organic toxicants, we analysed the relationship between community sensitivity SPEAR organic (average community sensitivity to organic toxicants) and natural and anthropogenic environmental factors in a large-scale river system, from alpine streams to a lowland river. The results show that SPEAR organic is largely independent of natural longitudinal factors, but strongly dependent on contamination with organic toxicants (petrochemicals and synthetic surfactants). Usage of SPEAR organic as a stressor-specific longitude-independent measure will facilitate detection of community disturbance by organic toxicants. - Indicator for organic toxicants at community level can be independent of natural environmental factors

On the solubility of nicotinic acid and isonicotinic acid in water and organic solvents

International Nuclear Information System (INIS)

Abraham, Michael H.; Acree, William E.

2013-01-01

Highlights: ► Solubilities of nicotinic acid and isonicotinic acids in organicsolvents have been determined. ► Solubilities are used to calculate Abraham descriptors for the two acids. ► These descriptors then yield water-solvent and gas-solvent partitions into numerous solvents. ► The solubility of the neutral acids in water is obtained. ► The method is straightforward and can be applied to any set of compound solubilities. -- Abstract: We have determined the solubility of nicotinic acid in four solvents and the solubility of isonicotinic acid in another four solvents. These results, together with literature data on the solubility of nicotinic acid in five other organic solvents and isonicotinic acid in four other organic solvents, have been analyzed through two linear Gibbs energy relationships in order to extract compound properties, or descriptors, that encode various solute–solvent interactions. The descriptors for nicotinic acid and isonicotinic acid can then be used in known equations for partition of solutes between water and organic solvents to predict partition coefficients and then further solubility in a host of organic solvents, as well as to predict a number of other physicochemical properties

Synthesis and in vitro toxicity of new dodecaborate-containing amino acids

International Nuclear Information System (INIS)

Slepukhina, Irina; Gabel, Detlef

2006-01-01

Two unnatural, boron-containing amino acids were synthesized by alkylation of S-(2-cyanoethyl)-thio-undecahydro-closo-dodecaborate(2-). S-(2-amino-2-carboxylpropyl)-thio-undecahydro-closo-dodecaborate (2-), containing a quaternary carbon atom, and O-(5-amino-5-carboxylpentyl)-oxy-undecahydro-closo-dodecaborate(2-) were evaluated for in vitro toxicity using V 79 Chinese hamster cells. (author)

Bile Acid Metabolism and Signaling

Science.gov (United States)

Chiang, John Y. L.

2015-01-01

Bile acids are important physiological agents for intestinal nutrient absorption and biliary secretion of lipids, toxic metabolites, and xenobiotics. Bile acids also are signaling molecules and metabolic regulators that activate nuclear receptors and G protein-coupled receptor (GPCR) signaling to regulate hepatic lipid, glucose, and energy homeostasis and maintain metabolic homeostasis. Conversion of cholesterol to bile acids is critical for maintaining cholesterol homeostasis and preventing accumulation of cholesterol, triglycerides, and toxic metabolites, and injury in the liver and other organs. Enterohepatic circulation of bile acids from the liver to intestine and back to the liver plays a central role in nutrient absorption and distribution, and metabolic regulation and homeostasis. This physiological process is regulated by a complex membrane transport system in the liver and intestine regulated by nuclear receptors. Toxic bile acids may cause inflammation, apoptosis, and cell death. On the other hand, bile acid-activated nuclear and GPCR signaling protects against inflammation in liver, intestine, and macrophages. Disorders in bile acid metabolism cause cholestatic liver diseases, dyslipidemia, fatty liver diseases, cardiovascular diseases, and diabetes. Bile acids, bile acid derivatives, and bile acid sequestrants are therapeutic agents for treating chronic liver diseases, obesity, and diabetes in humans. PMID:23897684

Accurate prediction of the toxicity of benzoic acid compounds in mice via oral without using any computer codes

International Nuclear Information System (INIS)

Keshavarz, Mohammad Hossein; Gharagheizi, Farhad; Shokrolahi, Arash; Zakinejad, Sajjad

2012-01-01

Highlights: ► A novel method is introduced for desk calculation of toxicity of benzoic acid derivatives. ► There is no need to use QSAR and QSTR methods, which are based on computer codes. ► The predicted results of 58 compounds are more reliable than those predicted by QSTR method. ► The present method gives good predictions for further 324 benzoic acid compounds. - Abstract: Most of benzoic acid derivatives are toxic, which may cause serious public health and environmental problems. Two novel simple and reliable models are introduced for desk calculations of the toxicity of benzoic acid compounds in mice via oral LD 50 with more reliance on their answers as one could attach to the more complex outputs. They require only elemental composition and molecular fragments without using any computer codes. The first model is based on only the number of carbon and hydrogen atoms, which can be improved by several molecular fragments in the second model. For 57 benzoic compounds, where the computed results of quantitative structure–toxicity relationship (QSTR) were recently reported, the predicted results of two simple models of present method are more reliable than QSTR computations. The present simple method is also tested with further 324 benzoic acid compounds including complex molecular structures, which confirm good forecasting ability of the second model.

Metal mixture toxicity to aquatic biota in laboratory experiments: Application of the WHAM-F{sub TOX} model

Energy Technology Data Exchange (ETDEWEB)

Tipping, E., E-mail: et@ceh.ac.uk; Lofts, S.

2013-10-15

Highlights: •Metal accumulation by living organisms is successfully simulated with WHAM. •Modelled organism-bound metal provides a measure of toxic exposure. •The toxic potency of individual bound metals is quantified by fitting toxicity data. •Eleven laboratory mixture toxicity data sets were parameterised. •Relatively little variability amongst individual test organisms is indicated. -- Abstract: The WHAM-F{sub TOX} model describes the combined toxic effects of protons and metal cations towards aquatic organisms through the toxicity function (F{sub TOX}), a linear combination of the products of organism-bound cation and a toxic potency coefficient (α{sub i}) for each cation. Organism-bound, metabolically-active, cation is quantified by the proxy variable, amount bound by humic acid (HA), as predicted by the WHAM chemical speciation model. We compared published measured accumulations of metals by living organisms (bacteria, algae, invertebrates) in different solutions, with WHAM predictions of metal binding to humic acid in the same solutions. After adjustment for differences in binding site density, the predictions were in reasonable line with observations (for logarithmic variables, r{sup 2} = 0.89, root mean squared deviation = 0.44), supporting the use of HA binding as a proxy. Calculated loadings of H{sup +}, Al, Cu, Zn, Cd, Pb and UO{sub 2} were used to fit observed toxic effects in 11 published mixture toxicity experiments involving bacteria, macrophytes, invertebrates and fish. Overall, WHAM-F{sub TOX} gave slightly better fits than a conventional additive model based on solution concentrations. From the derived values of α{sub i}, the toxicity of bound cations can tentatively be ranked in the order: H < Al < (Zn–Cu–Pb–UO{sub 2}) < Cd. The WHAM-F{sub TOX} analysis indicates much narrower ranges of differences amongst individual organisms in metal toxicity tests than was previously thought. The model potentially provides a means to

Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust.

Science.gov (United States)

Chang, Chang-Tang; Chen, Bor-Yann

2008-05-30

This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5 alpha. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX.

Toxicity assessment of volatile organic compounds and polycyclic aromatic hydrocarbons in motorcycle exhaust

International Nuclear Information System (INIS)

Chang, C.-T.; Chen, B.-Y.

2008-01-01

This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5α. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC 50 , was approximately as follows: PAHs > two-stroke engines > four-stroke engines > BTEX

Degradation of organophosphoric acid triesters by the aquatic bacteria and toxicity to fish; Yuki rinsan toriester no suichu saikin ni yoru bunkai to dokusei

Energy Technology Data Exchange (ETDEWEB)

Kawai, S. [Kobe College, Hyogo (Japan)

1996-09-10

This paper describes biodegradation of organophosphoric acid triesters (OPEs) in water environment, in particular, by aquatic bacteria. In culture experiment using river water in Osaka, aryl system OPEs such as triphenyl phosphate (TPP) and tricresyl phosphate (TCP) are more easily degraded than alkyl system OPEs, and OPEs including Cl are hardly degraded. Properties of isolated TBP degradation bacteria and enzymes, and TCP degradation bacteria isolated from Mukogawa river water are examined. OPEs are toxic to fishes equivalently to or more than organophosphoric system pesticides. However, the cause of their toxicity can`t be interpreted only by cholinesterase activity hindrance of nervous system. Absorption, accumulation, metabolism and degradation of OPEs are dependent on fishes and kinds of OPEs. Although the toxicity evaluation using experimental animals is important, the evaluation using cultured bacteria is recognizing once again from various viewpoints. Direct toxicity of OPEs to fishes or aquatic organisms is yet unidentified, however, the influence of OPEs on human beings is rather important. 39 refs., 10 figs., 2 tabs.

Effects of soil organic matter content on cadmium toxicity in Eisenia fetida: implications for the use of biomarkers and standard toxicity tests.

Science.gov (United States)

Irizar, A; Rodríguez, M P; Izquierdo, A; Cancio, I; Marigómez, I; Soto, M

2015-01-01

Bioavailability is affected by soil physicochemical characteristics such as pH and organic matter (OM) content. In addition, OM constitutes the energy source of Eisenia fetida, a well established model species for soil toxicity assessment. The present work aimed at assessing the effects of changes in OM content on the toxicity of Cd in E. fetida through the measurement of neutral red uptake (NRU) and mortality, growth, and reproduction (Organisation for Economic Co-operation and Development [OECD] Nos. 207 and 222). Complementarily, metallothionein (MT) and catalase transcription levels were measured. To decrease variability inherent to natural soils, artificial soils (Organization for Economic Cooperation and Development 1984) with different OM content (6, 10, and 14%) and spiked with Cd solutions at increasing concentrations were used. Low OM in soil decreased soil ingestion and Cd bioaccumulation but also increased Cd toxicity causing lower NRU of coelomocytes, 100 % mortality, and stronger reproduction impairment, probably due to the lack of energy to maintain protection mechanisms (production of MT).Cd bioaccumulation did not reflect toxicity, and OM played a pivotal role in Cd toxicity. Thus, OM content should be taken into account when using E. fetida in in vivo exposures for soil health assessment.

Effects of benzoic acid and cadmium toxicity on wheat seedlings

Directory of Open Access Journals (Sweden)

Kavita Yadav

2013-06-01

Full Text Available Benzoic acid (BA and Cd exhibit cumulative effects on plants due to their accumulation in the soil. The present study reports the effects of BA an allelochemical, Cd and their combinations on seed germination, seedling growth, biochemical parameters, and response of antioxidant enzymes in Triticum aestivum L. The experiment was conducted in sand supplemented with Hoagland nutrient solution. Benzoic acid was applied at concentrations of 0.5, 1.0, and 1.5 mM with or without Cd (7 mg L-1 to observe effects of allelochemical and Cd alone and in combination on wheat. Both stresses exhibited inhibitory effect on growth and metabolism of wheat seedlings. The allelochemical in single and combined treatments with Cd decreased seedling growth as compared to Cd stress. The two stresses significantly enhanced malondialdehyde content of wheat seedlings. The activity of other antioxidant enzymes, viz. superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX, and guaiacol peroxidase (POX were also recorded. SOD increased in seedlings under the two stresses. CAT more prominently ameliorates the toxic effects of H2O2 as compared with APX and POX and protected wheat seedlings from oxidative stress. Allelochemical buttressed the toxic effect of Cd on wheat seedlings.

Surfactant-Enhanced Organic Acid Inactivation of Tulane Virus, a Human Norovirus Surrogate.

Science.gov (United States)

Lacombe, Alison; Niemira, Brendan A; Gurtler, Joshua B; Kingsley, David H; Li, Xinhui; Chen, Haiqiang

2018-02-01

Combination treatments of surfactants and phenolic or short-chain organic acids (SCOA) may act synergistically or additively as sanitizers to inactive foodborne viruses and prevent outbreaks. The purpose of this study was to investigate the effect of gallic acid (GA), tannic acid, p-coumaric acid, lactic acid (LA), or acetic acid (AA), in combination with sodium dodecyl sulfate (SDS), against Tulane virus (TV), a surrogate for human norovirus. An aqueous stock solution of phenolic acids or SCOA with or without SDS was prepared and diluted in a twofold dilution series to 2× the desired concentration with cell growth media (M119 plus 10% fetal bovine serum). The solution was inoculated with an equal proportion of 6 log PFU/mL TV with a treatment time of 5 min. The survival of TV was quantified using a plaque assay with LLC-MK2 cells. The minimum virucidal concentration was 0.5:0.7% (v/v) for LA-SDS at pH 3.5 (4.5-PFU/mL reduction) and 0.5:0.7% (v/v) AA-SDS at pH 4.0 (2.6-log PFU/mL reduction). GA and SDS demonstrated a minimum virucidal concentration of 12.5 mM GA-SDS at pH 7.0 (0.2:0.3% GA-SDS) with an 0.8-log PFU/mL reduction and 50 mM GA-SDS (0.8:1.4% GA-SDS at pH 7.0) increased log reduction to 1.6 log PFU/mL. The combination treatments of AA or LA with SDS at pH 7.0 did not produce significant log reduction, nor did individual treatments of tannic acid, GA, p-coumaric acid, AA, LA, or SDS. This study demonstrates that a surfactant, such as SDS, aids in the phenolic acid and SCOA toxicities against viruses. However, inactivation of TV by combination treatments is contingent upon the pH of the sanitizing solution being lower than the pK a value of the organic acid being used. This information can be used to develop sanitizing washes to disinfect food contact surfaces, thereby aiding in the prevention of foodborne outbreaks.

Acid digestion of organic materials

International Nuclear Information System (INIS)

Capp, P.D.

1988-01-01

To overcome the high temperatures involved in straight incineration of organic waste and the difficulty of extracting actinides from the ash various research establishments throughout the world, including Winfrith and Harwell in the UK, have carried out studies on an alternative chemical combustion method known as acid digestion. The basis of the technique is to digest the waste in concentrated sulphuric acid containing a few percent of nitric acid at a temperature of about 250 0 C. Acid digestion residues consist mainly of non-refractory inorganic sulphates and oxides from which any actinide materials can easily be extracted. (author)

In Utero Domoic Acid Toxicity: A Fetal Basis to Adult Disease in the California Sea Lion (Zalophus californianus

Directory of Open Access Journals (Sweden)

Tanja S. Zabka

2008-06-01

Full Text Available California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT poisoning and infectious disease in the 1970's and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion.

Organic acids in naturally colored surface waters

Science.gov (United States)

Lamar, William L.; Goerlitz, D.F.

1966-01-01

Most of the organic matter in naturally colored surface waters consists of a mixture of carboxylic acids or salts of these acids. Many of the acids color the water yellow to brown; however, not all of the acids are colored. These acids range from simple to complex, but predominantly they are nonvolatile polymeric carboxylic acids. The organic acids were recovered from the water by two techniques: continuous liquid-liquid extraction with n-butanol and vacuum evaporation at 50?C (centigrade). The isolated acids were studied by techniques of gas, paper, and column chromatography and infrared spectroscopy. About 10 percent of the acids recovered were volatile or could be made volatile for gas chromatographic analysis. Approximately 30 of these carboxylic acids were isolated, and 13 of them were individually identified. The predominant part of the total acids could not be made volatile for gas chromatographic analysis. Infrared examination of many column chromatographic fractions indicated that these nonvolatile substances are primarily polymeric hydroxy carboxylic acids having aromatic and olefinic unsaturation. The evidence suggests that some of these acids result from polymerization in aqueous solution. Elemental analysis of the sodium fusion products disclosed the absence of nitrogen, sulfur, and halogens.

ALUMINUM TOXICITY VS SALICYLIC ACID EFFECTS IN PEARL MILLET METHYLOME.

OpenAIRE

Baba Ngom; Edward Mamati; Ibrahima Sarr; Josphert Kimatu.

2018-01-01

Aluminum toxicity is one of most distributed plant abiotic stress in the world, causing root inhibition and therefore crop losses. Plants continuously adapt its defense to abiotic stresses through different mechanisms including DNA methylation. The methylome variation is influenced by external cues from environment or by hormonal signals. Salicylic acid is one of the most important hormones in plants, directing growth and defense. Its application is seen having the capacity to elicit plant de...

Role of glucuronidation for hepatic detoxification and urinary elimination of toxic bile acids during biliary obstruction.

Directory of Open Access Journals (Sweden)

Martin Perreault

Full Text Available Biliary obstruction, a severe cholestatic condition, results in a huge accumulation of toxic bile acids (BA in the liver. Glucuronidation, a conjugation reaction, is thought to protect the liver by both reducing hepatic BA toxicity and increasing their urinary elimination. The present study evaluates the contribution of each process in the overall BA detoxification by glucuronidation. Glucuronide (G, glycine, taurine conjugates, and unconjugated BAs were quantified in pre- and post-biliary stenting urine samples from 12 patients with biliary obstruction, using liquid chromatography-tandem mass spectrometry (LC-MS/MS. The same LC-MS/MS procedure was used to quantify intra- and extracellular BA-G in Hepatoma HepG2 cells. Bile acid-induced toxicity in HepG2 cells was evaluated using MTS reduction, caspase-3 and flow cytometry assays. When compared to post-treatment samples, pre-stenting urines were enriched in glucuronide-, taurine- and glycine-conjugated BAs. Biliary stenting increased the relative BA-G abundance in the urinary BA pool, and reduced the proportion of taurine- and glycine-conjugates. Lithocholic, deoxycholic and chenodeoxycholic acids were the most cytotoxic and pro-apoptotic/necrotic BAs for HepG2 cells. Other species, such as the cholic, hyocholic and hyodeoxycholic acids were nontoxic. All BA-G assayed were less toxic and displayed lower pro-apoptotic/necrotic effects than their unconjugated precursors, even if they were able to penetrate into HepG2 cells. Under severe cholestatic conditions, urinary excretion favors the elimination of amidated BAs, while glucuronidation allows the conversion of cytotoxic BAs into nontoxic derivatives.

Organic acids in cloud water and rainwater at a mountain site in acid rain areas of South China.

Science.gov (United States)

Sun, Xiao; Wang, Yan; Li, Haiyan; Yang, Xueqiao; Sun, Lei; Wang, Xinfeng; Wang, Tao; Wang, Wenxing

2016-05-01

To investigate the chemical characteristics of organic acids and to identify their source, cloud water and rainwater samples were collected at Mount Lu, a mountain site located in the acid rain-affected area of south China, from August to September of 2011 and March to May of 2012. The volume-weighted mean (VWM) concentration of organic acids in cloud water was 38.42 μeq/L, ranging from 7.45 to 111.46 μeq/L, contributing to 2.50 % of acidity. In rainwater samples, organic acid concentrations varied from 12.39 to 68.97 μeq/L (VWM of 33.39 μeq/L). Organic acids contributed significant acidity to rainwater, with a value of 17.66 %. Formic acid, acetic acid, and oxalic acid were the most common organic acids in both cloud water and rainwater. Organic acids had an obviously higher concentration in summer than in spring in cloud water, whereas there was much less discrimination in rainwater between the two seasons. The contribution of organic acids to acidity was lower during summer than during spring in both cloud water (2.20 % in summer vs 2.83 % in spring) and rainwater (12.24 % in summer vs 19.89 % in spring). The formic-to-acetic acid ratio (F/A) showed that organic acids were dominated by primary emissions in 71.31 % of the cloud water samples and whole rainwater samples. Positive matrix factorization (PMF) analysis determined four factors as the sources of organic acids in cloud water, including biogenic emissions (61.8 %), anthropogenic emissions (15.28 %), marine emissions (15.07 %) and soil emissions (7.85 %). The findings from this study imply an indispensable role of organic acids in wet deposition, but organic acids may have a limited capacity to increase ecological risks in local environments.

Fatty acid synthase cooperates with glyoxalase 1 to protect against sugar toxicity.

Directory of Open Access Journals (Sweden)

Damien Garrido

2015-02-01

Full Text Available Fatty acid (FA metabolism is deregulated in several human diseases including metabolic syndrome, type 2 diabetes and cancers. Therefore, FA-metabolic enzymes are potential targets for drug therapy, although the consequence of these treatments must be precisely evaluated at the organismal and cellular levels. In healthy organism, synthesis of triacylglycerols (TAGs-composed of three FA units esterified to a glycerol backbone-is increased in response to dietary sugar. Saturation in the storage and synthesis capacity of TAGs is associated with type 2 diabetes progression. Sugar toxicity likely depends on advanced-glycation-end-products (AGEs that form through covalent bounding between amine groups and carbonyl groups of sugar or their derivatives α-oxoaldehydes. Methylglyoxal (MG is a highly reactive α-oxoaldehyde that is derived from glycolysis through a non-enzymatic reaction. Glyoxalase 1 (Glo1 works to neutralize MG, reducing its deleterious effects. Here, we have used the power of Drosophila genetics to generate Fatty acid synthase (FASN mutants, allowing us to investigate the consequence of this deficiency upon sugar-supplemented diets. We found that FASN mutants are lethal but can be rescued by an appropriate lipid diet. Rescued animals do not exhibit insulin resistance, are dramatically sensitive to dietary sugar and accumulate AGEs. We show that FASN and Glo1 cooperate at systemic and cell-autonomous levels to protect against sugar toxicity. We observed that the size of FASN mutant cells decreases as dietary sucrose increases. Genetic interactions at the cell-autonomous level, where glycolytic enzymes or Glo1 were manipulated in FASN mutant cells, revealed that this sugar-dependent size reduction is a direct consequence of MG-derived-AGE accumulation. In summary, our findings indicate that FASN is dispensable for cell growth if extracellular lipids are available. In contrast, FA-synthesis appears to be required to limit a cell

Toxicity of organic chemical pollution in groundwater downgradient of a landfill (Grindsted, Denmark)

DEFF Research Database (Denmark)

Baun, Anders; Jensen, S. D.; Bjerg, Poul Løgstrup

2000-01-01

The aim of the present study was to describe the occurrence and distribution of toxicity related to organic chemical contaminants in the leachate plume downgradient of the Grindsted Landfill (Denmark). A total of 27 groundwater samples were preconcentrated by solidphase extraction (SPE) using XAD-2...... bioassays, it was concluded that SPE extracts of groundwater collected close to the landfill were toxic. The toxicity decreased with the distance from the landfill. At distances greater than 80 m from the border of the landfill, the groundwater toxicity was not significantly different from the background...... characterization and hazard ranking of groundwater polluted with complex chemical mixtures, such as landfill leachates....

High-Density Real-Time PCR-Based in Vivo Toxicogenomic Screen to Predict Organ-Specific Toxicity

Directory of Open Access Journals (Sweden)

Laszlo G. Puskas

2011-09-01

Full Text Available Toxicogenomics, based on the temporal effects of drugs on gene expression, is able to predict toxic effects earlier than traditional technologies by analyzing changes in genomic biomarkers that could precede subsequent protein translation and initiation of histological organ damage. In the present study our objective was to extend in vivo toxicogenomic screening from analyzing one or a few tissues to multiple organs, including heart, kidney, brain, liver and spleen. Nanocapillary quantitative real-time PCR (QRT-PCR was used in the study, due to its higher throughput, sensitivity and reproducibility, and larger dynamic range compared to DNA microarray technologies. Based on previous data, 56 gene markers were selected coding for proteins with different functions, such as proteins for acute phase response, inflammation, oxidative stress, metabolic processes, heat-shock response, cell cycle/apoptosis regulation and enzymes which are involved in detoxification. Some of the marker genes are specific to certain organs, and some of them are general indicators of toxicity in multiple organs. Utility of the nanocapillary QRT-PCR platform was demonstrated by screening different references, as well as discovery of drug-like compounds for their gene expression profiles in different organs of treated mice in an acute experiment. For each compound, 896 QRT-PCR were done: four organs were used from each of the treated four animals to monitor the relative expression of 56 genes. Based on expression data of the discovery gene set of toxicology biomarkers the cardio- and nephrotoxicity of doxorubicin and sulfasalazin, the hepato- and nephrotoxicity of rotenone, dihydrocoumarin and aniline, and the liver toxicity of 2,4-diaminotoluene could be confirmed. The acute heart and kidney toxicity of the active metabolite SN-38 from its less toxic prodrug, irinotecan could be differentiated, and two novel gene markers for hormone replacement therapy were identified

Edaravone ameliorates the adverse effects of valproic acid toxicity in small intestine.

Science.gov (United States)

Oktay, S; Alev, B; Tunali, S; Emekli-Alturfan, E; Tunali-Akbay, T; Koc-Ozturk, L; Yanardag, R; Yarat, A

2015-06-01

Valproic acid (VPA) is a drug used for the treatment of epilepsy, bipolar psychiatric disorders, and migraine. Previous studies have reported an increased generation of reactive oxygen species and oxidative stress in the toxic mechanism of VPA. Edaravone, a free radical scavenger for clinical use, can quench free radical reaction by trapping a variety of free radical species. In this study, effect of edaravone on some small intestine biochemical parameters in VPA-induced toxicity was investigated. Thirty seven Sprague Dawley female rats were randomly divided into four groups. The groups include control group, edaravone (30 mg(-1) kg(-1) day(-1)) given group, VPA (0.5 g(-1) kg(-1) day(-1)) given group, VPA + edaravone (in same dose) given group. Edaravone and VPA were given intraperitoneally for 7 days. Biochemical parameters such as malondialdehyde, as an index of lipid peroxidation(LPO), sialic acid (SA), glutathione levels and glutathione peroxidase, glutathione-S-transferase, superoxide dismutase, catalase, myeloperoxidase, alkaline phosphatase (ALP), and tissue factor (TF) activities were determined in small intestine samples by colorimetric methods. Decreased small intestine antioxidant enzyme activities, increased LPO and SA levels, and increased activities of ALP and TF were detected in the VPA group. Based on our results edaravone may be suggested to reverse the oxidative stress and inflammation due to VPA-induced small intestine toxicity. © The Author(s) 2014.

Comparing the Effect of Diets Treated with Different Organic Acids ...

African Journals Online (AJOL)

An experiment was conducted to compare the growth and economics of adding organic acids to diets of broiler chickens. The organic acids were sorbic benzoic lactic and propionic acids. 150 day old Hubbard chicks were used. There were five treatments. Diet 1 which served as control contained no organic acid. Diets 2, 3 ...

Effects-Directed Analysis of Dissolved Organic Compounds in Oil Sands Process-Affected Water.

Science.gov (United States)

Morandi, Garrett D; Wiseman, Steve B; Pereira, Alberto; Mankidy, Rishikesh; Gault, Ian G M; Martin, Jonathan W; Giesy, John P

2015-10-20

Acute toxicity of oil sands process-affected water (OSPW) is caused by its complex mixture of bitumen-derived organics, but the specific chemical classes that are most toxic have not been demonstrated. Here, effects-directed analysis was used to determine the most acutely toxic chemical classes in OSPW collected from the world's first oil sands end-pit lake. Three sequential rounds of fractionation, chemical analysis (ultrahigh resolution mass spectrometry), and acute toxicity testing (96 h fathead minnow embryo lethality and 15 min Microtox bioassay) were conducted. Following primary fractionation, toxicity was primarily attributable to the neutral extractable fraction (F1-NE), containing 27% of original organics mass. In secondary fractionation, F1-NE was subfractionated by alkaline water washing, and toxicity was primarily isolated to the ionizable fraction (F2-NE2), containing 18.5% of the original organic mass. In the final round, chromatographic subfractionation of F2-NE2 resulted in two toxic fractions, with the most potent (F3-NE2a, 11% of original organic mass) containing predominantly naphthenic acids (O2(-)). The less-toxic fraction (F3-NE2b, 8% of original organic mass) contained predominantly nonacid species (O(+), O2(+), SO(+), NO(+)). Evidence supports naphthenic acids as among the most acutely toxic chemical classes in OSPW, but nonacidic species also contribute to acute toxicity of OSPW.

Organ- and species-specific biological activity of rosmarinic acid

NARCIS (Netherlands)

Iswandana, R.; Pham, B.T.; van Haaften, W.T.; Luangmonkong, T.; Oosterhuis, D.; Mutsaers, H.A.M.; Olinga, P.

2016-01-01

Rosmarinic acid (RA), a compound found in several plant species, has beneficial properties, including anti-inflammatory and antibacterial effects. We investigated the toxicity, anti-inflammatory, and antifibrotic effects of RA using precision-cut liver slices (PCLS) and precision-cut intestinal

Liver function and bacteriology of organs in broiler inoculated with nalidixic acid-resistant Salmonella Typhimurium and treated with organic acids

Directory of Open Access Journals (Sweden)

Tatiane M. Rocha

2013-07-01

Full Text Available AbAns etxrpaecritment was carried out with 630 one-day-old chicks to evaluate the effects of organic acids when birds were experimentally inoculated with Salmonella Typhimurium. Liver damage and the persistence of the bacterium in the organs were evaluated as well. Broilers were distributed in a completely randomised experimental design in a 3×2 factorial arrangement of six treatments with seven replicates of 15 birds each. Birds were inoculated with saline solution or the bacterium via gavage at 1 day of age, or were offered a feed containing or not the organic acid blend for the period of 7 to 14 days of age. A dose of 5.0x102 colony-forming units (CFU/0.5 mL of Salmonella Typhimurium was used for inoculation both via gavage and feed. The parameters evaluated are weight, liver histopathology, liver and serum biochemistry, and bacteriological analyses of the caeca, crop, spleen, and liver and heart pool. At 21 and 28 days of age, the liver of the non-inoculated groups was significantly lighter as compared to the other treatments. Birds fed organic acids presented lower bacterial isolation rates in all organs tested. Birds inoculated in the crop and treated with organic acids presented lower E. coli CFU counts (P<0.05. Birds inoculated with Salmonella presented significant changes (P<0.05 in liver enzymes, as detected by serum biochemistry, and in liver histopathology. It was concluded that organic acids effectively controlled Salmonella Typhimurium and did not cause any liver damage.

Electron beam treatment of toxic volatile organic compounds and dioxins

International Nuclear Information System (INIS)

Kojima, Takuji

2006-01-01

Considerations of wastes based on the reduction, reuse and recycle in daily life are primary measures to conserve our environment, but the control technology is necessary to support these measures. The electron beam (EB) process is promising as an advanced purification process having advantages such as a quick treatment of big volume gas, applicability even for very low concentration pollutants as the further purification at the downstream of existing process, and decomposition of pollutants into non-toxic substances by one process. The EB technology has been developed for treatment of toxic volatile organic compounds (VOCs) in ventilation gas and dioxins in solid waste incineration flue gas. (author)

Economics of feeding drinking water containing organic acids to ...

African Journals Online (AJOL)

A feeding trial was conducted to determine the economic effect of acidifying drinking water of broiler chickens with organic acids. The organic acids were acetic, butyric, citric and formic acids, each offered at 0.25%. The control did not contain any of the acids. One hundred and fifty (150) day old AborAcre - plus chicks were ...

Acidity controls on dissolved organic carbon mobility in organic soils

Czech Academy of Sciences Publication Activity Database

Evans, Ch. D.; Jones, T.; Burden, A.; Ostle, N.; Zielinski, P.; Cooper, M.; Peacock, M.; Clark, J.; Oulehle, Filip; Cooper, D.; Freeman, Ch.

2012-01-01

Roč. 18, č. 11 (2012), s. 3317-3331 ISSN 1354-1013 Institutional support: RVO:67179843 Keywords : acidity * dissolved organic carbon * organic soil * peat * podzol * soil carbon * sulphur Subject RIV: EH - Ecology, Behaviour Impact factor: 6.910, year: 2012

Effect of Marine Omega 3 Fatty Acids on Methylmercury-Induced Toxicity in Fish and Mammalian Cells In Vitro

Directory of Open Access Journals (Sweden)

O. J. Nøstbakken

2012-01-01

Full Text Available Methylmercury (MeHg is a ubiquitous environmental contaminant which bioaccumulates in marine biota. Fish constitute an important part of a balanced human diet contributing with health beneficial nutrients but may also contain contaminants such as MeHg. Interactions between the marine n-3 fatty acids eicosapentaenoic acid (20:5n-3, EPA and docosahexaenoic acid (22:6n-3, DHA with MeHg-induced toxicity were investigated. Different toxic and metabolic responses were studied in Atlantic salmon kidney (ASK cell line and the mammalian kidney-derived HEK293 cell line. Both cell lines were preincubated with DHA or EPA prior to MeHg-exposure, and cell toxicity was assessed differently in the cell lines by MeHg-uptake in cells (ASK and HEK293, proliferation (HEK293 and ASK, apoptosis (ASK, oxidation of the red-ox probe roGFP (HEK293, and regulation of selected toxicological and metabolic transcriptional markers (ASK. DHA was observed to decrease the uptake of MeHg in HEK293, but not in ASK cells. DHA also increased, while EPA decreased, MeHg-induced apoptosis in ASK. MeHg exposure induced changes in selected metabolic and known MeHg biomarkers in ASK cells. Both DHA and MeHg, but not EPA, oxidized roGFP in HEK293 cells. In conclusion, marine n-3 fatty acids may ameliorate MeHg toxicity, either by decreasing apoptosis (EPA or by reducing MeHg uptake (DHA. However, DHA can also augment MeHg toxicity by increasing oxidative stress and apoptosis when combined with MeHg.

Use of a (Quantitative) Structure-Activity Relationship [(Q)SAR] model to predict the toxicity of naphthenic acids

DEFF Research Database (Denmark)

Frank, Richard; Sanderson, Hans; Kavanagh, Richard

2010-01-01

Naphthenic acids (NAs) are a complex mixture of carboxylic acids that are natural constituents of oil sand found in north-eastern Alberta, Canada.  NAs are released and concentrated in the alkaline water used in the extraction of bitumen from oil sand sediment.  NAs have been identified...... as the principal toxic components of oil sands process-affected water (OSPW), and microbial degradation of lower molecular weight (MW) NAs decreases the toxicity of NA mixtures in OSPW.  Analysis by proton nuclear magnetic resonance spectroscopy indicated that larger, more cyclic NAs contain greater carboxylic...

Diclofenac toxicity in Gyps vulture is associated with decreased uric acid excretion and not renal portal vasoconstriction.

Science.gov (United States)

Naidoo, V; Swan, G E

2009-04-01

Diclofenac (DF), a non-steroidal anti-inflammatory drug (NSAID), is largely regarded as one of the most devastating environmental toxicant in recent times, after accidental exposure via their food-chain lead to massive mortalities in three vulture species on the Asian subcontinent. Although the use of diclofenac was recently banned on the Indian subcontinent, following the favourable safety profile of meloxicam, its mechanism of toxicity remains unknown. In an attempt to establish this mechanism, we test three hypotheses using models established from either the domestic chicken (Gallus domesticus) or the African White-backed vulture (Gyps africanus). We demonstrate that both DF and meloxicam are toxic to renal tubular epithelial (RTE) cells following 12 h of exposure, due to an increase in production of reactive oxygen species (ROS), which could be temporarily ameliorated by pre-incubation with uric acid (UA). When cultures were incubated with either drug for only 2 h, meloxicam showed no toxicity in contrast to diclofenac. In both cases no increase in ROS production was evident. In addition, diclofenac decreased the transport of uric acid, by interfering with the p-amino-hippuric acid (PAH) channel. We conclude that vulture susceptibility to diclofenac results from a combination of an increased ROS, interference with UA transport and the duration of exposure.

Potential citric acid exposure and toxicity to Hawaiian hoary bats (Lasiurus cinereus semotus) associated with Eleutherodactylus frog control.

Science.gov (United States)

Pitt, William C; Witmer, Gary W; Jojola, Susan M; Sin, Hans

2014-04-01

We examined potential exposure of Hawaiian hoary bats (Lasiurus cinereus semotus) to citric acid, a minimum risk pesticide registered for control of invasive Eleutherodactylus frog populations. Hoary bats are nocturnal insectivores that roost solitarily in foliage, federally listed as endangered, and are endemic to Hawaii. Oral ingestion during grooming of contaminated fur appears to be the principal route by which these bats might be exposed to citric acid. We made assessments of oral toxicity, citric acid consumption, retention of material on fur, and grooming using big brown bats (Eptesicus fuscus) as a surrogate species. We evaluated both ground application and aerial application of 16 % solutions of citric acid during frog control operations. Absorbent bat effigies exposed to ground and aerial operational spray applications retained means of 1.54 and 0.02 g, respectively, of dry citric acid, although retention by the effigies was much higher than bat carcasses drenched in citric acid solutions. A high dose delivered orally (2,811 mg/kg) was toxic to the big brown bats and emesis occurred in 1 bat dosed as low as the 759 mg/kg level. No effect was observed with the lower doses examined (≤ 542 mg/kg). Bats sprayed with 5 ml of 16 % (w/w) citric acid solution showed no evidence of intoxication. In field situations, it is unlikely that bats would be sprayed directly or ingest much citric acid retained by fur. Based on our observations, we believe Hawaiian hoary bats to be at very low risk from harmful exposure to a toxic dose of citric acid during frog control operations.

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-).

Science.gov (United States)

Chhetri, Ravi Kumar; Baun, Anders; Andersen, Henrik Rasmus

2017-05-01

Environmental effect evaluation of disinfection of combined sewer overflow events with alternative chemical disinfectants requires that the environmental toxicity of the disinfectants and the main by-products of their use are known. Many disinfectants degrade quickly in water which should be included in the evaluation of both their toxicity as determined in standardized tests and their possible negative effect in the water environment. Here we evaluated according to the standardized ISO 8692 test the toxicity towards the green microalgae, Pseudokirchneriella subcapitata, of three disinfectants: performic acid (PFA), peracetic acid (PAA) and chlorine dioxide (ClO 2 ) as well as two by-products of their use: hydrogen peroxide (H 2 O 2 ) and chlorite. All of the five chemicals investigated showed clear toxicity to the algae with well-defined dose response curves. The EC 50 values ranged from 0.16 to 2.9mg/L based on nominal concentrations leading to the labeling of the chemicals as either toxic or very toxic. The five investigated chemicals decreased in toxicity in the order chlorine dioxide, performic acid, peracetic acid, chlorite and hydrogen peroxide. The stability of the chemicals increased in the same order as the toxicity decrease. This indicates that even though ClO 2 has the highest environmental hazard potential, it may still be suitable as an alternative disinfectant due to its rapid degradation in water. Copyright © 2016 Elsevier GmbH. All rights reserved.

Separation and recovery of organic acids from fermented kitchen ...

African Journals Online (AJOL)

Organic acids produced from anaerobic digestion of kitchen waste were recovered using a new integrated method which consisted of freezing and thawing, centrifugation, filtration and evaporation. The main organic acid produced was lactic acid (98%). After the freezing and thawing process, 73% of the total suspended ...

Dual responsive dysprosium-doped hydroxyapatite particles and toxicity reduction after functionalization with folic and glucuronic acids

Energy Technology Data Exchange (ETDEWEB)

Sánchez Lafarga, Ana Karen; Pacheco Moisés, Fermín P. [Departamento de Química, Universidad de Guadalajara, Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico); Gurinov, Andrey [Research Resources Center for Magnetic Resonance, Saint Petersburg State University, Universitetskij pr. 26, 198504 St. Petersburg (Russian Federation); Ortiz, Genaro Gabriel [Laboratorio Desarrollo-Envejecimiento, Enfermedades Neurodegenerativas, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano de Seguro Social (IMSS), Guadalajara, Jalisco (Mexico); Carbajal Arízaga, Gregorio Guadalupe, E-mail: gregoriocarbajal@yahoo.com.mx [Departamento de Química, Universidad de Guadalajara, Marcelino García Barragán 1421, C.P. 44430, Guadalajara, Jalisco (Mexico)

2015-03-01

The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488 nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. - Highlights: • Hydroxyapatite functionalized with glucuronic acid reduced oxidative stress in rats. • Functionalization with folic acid reduced oxidative stress in rats. • Dysprosium doping does not affect the crystalline structure of hydroxyapatite. • Dysprosium doped particles are visible in fluorescent microscope. • Dysprosium doped particles act as MRI contrast agents.

Dual responsive dysprosium-doped hydroxyapatite particles and toxicity reduction after functionalization with folic and glucuronic acids

International Nuclear Information System (INIS)

Sánchez Lafarga, Ana Karen; Pacheco Moisés, Fermín P.; Gurinov, Andrey; Ortiz, Genaro Gabriel; Carbajal Arízaga, Gregorio Guadalupe

2015-01-01

The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488 nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. - Highlights: • Hydroxyapatite functionalized with glucuronic acid reduced oxidative stress in rats. • Functionalization with folic acid reduced oxidative stress in rats. • Dysprosium doping does not affect the crystalline structure of hydroxyapatite. • Dysprosium doped particles are visible in fluorescent microscope. • Dysprosium doped particles act as MRI contrast agents

Phosphorus application reduces aluminum toxicity in two Eucalyptus clones by increasing its accumulation in roots and decreasing its content in leaves.

Science.gov (United States)

Teng, Weichao; Kang, Yachao; Hou, Wenjuan; Hu, Houzhen; Luo, Wenji; Wei, Jie; Wang, Linghui; Zhang, Boyu

2018-01-01

Under acidic conditions, aluminum (Al) toxicity is an important factor limiting plant productivity; however, the application of phosphorus (P) might alleviate the toxic effects of Al. In this study, seedlings of two vegetatively propagated Eucalyptus clones, E. grandis × E. urophylla 'G9' and E. grandis × E. urophylla 'DH32-29'were subjected to six treatments (two levels of Al stress and three levels of P). Under excessive Al stress, root Al content was higher, whereas shoot and leaf Al contents were lower with P application than those without P application. Further, Al accumulation was higher in the roots, but lower in the shoots and leaves of G9 than in those of DH32-29. The secretion of organic acids was higher under Al stress than under no Al stress. Further, under Al stress, the roots of G9 secreted more organic acids than those of DH32-29. With an increase in P supply, Al-induced secretion of organic acids from roots decreased. Under Al stress, some enzymes, including PEPC, CS, and IDH, played important roles in organic acid biosynthesis and degradation. Thus, our results indicate that P can reduce Al toxicity via the fixation of elemental Al in roots and restriction of its transport to stems and leaves, although P application cannot promote the secretion of organic acid anions. Further, the higher Al-resistance of G9 might be attributed to the higher Al accumulation in and organic acid anion secretion from roots and the lower levels of Al in leaves.

Phosphorus application reduces aluminum toxicity in two Eucalyptus clones by increasing its accumulation in roots and decreasing its content in leaves.

Directory of Open Access Journals (Sweden)

Weichao Teng

Full Text Available Under acidic conditions, aluminum (Al toxicity is an important factor limiting plant productivity; however, the application of phosphorus (P might alleviate the toxic effects of Al. In this study, seedlings of two vegetatively propagated Eucalyptus clones, E. grandis × E. urophylla 'G9' and E. grandis × E. urophylla 'DH32-29'were subjected to six treatments (two levels of Al stress and three levels of P. Under excessive Al stress, root Al content was higher, whereas shoot and leaf Al contents were lower with P application than those without P application. Further, Al accumulation was higher in the roots, but lower in the shoots and leaves of G9 than in those of DH32-29. The secretion of organic acids was higher under Al stress than under no Al stress. Further, under Al stress, the roots of G9 secreted more organic acids than those of DH32-29. With an increase in P supply, Al-induced secretion of organic acids from roots decreased. Under Al stress, some enzymes, including PEPC, CS, and IDH, played important roles in organic acid biosynthesis and degradation. Thus, our results indicate that P can reduce Al toxicity via the fixation of elemental Al in roots and restriction of its transport to stems and leaves, although P application cannot promote the secretion of organic acid anions. Further, the higher Al-resistance of G9 might be attributed to the higher Al accumulation in and organic acid anion secretion from roots and the lower levels of Al in leaves.

Preparation of five 3-MCPD fatty acid esters, and the effects of their chemical structures on acute oral toxicity in Swiss mice.

Science.gov (United States)

Liu, Man; Liu, Jie; Wu, Yizhen; Gao, Boyan; Wu, Pingping; Shi, Haiming; Sun, Xiangjun; Huang, Haiqiu; Wang, Thomas Ty; Yu, Liangli Lucy

2017-02-01

3-monochloro-1, 2-propanediol fatty acid esters (3-MCPDEs) comprise a group of food toxicants formed during food processing. 3-MCPDEs have received increasing attention concerning their potential negative effects on human health. However, reports on the toxicity of 3-MCPD esters are still limited. To determine the effects of fatty acid substitutions on the toxicity of their esters, 1-stearic, 1-oleic, 1-linoleic, 1-linoleic-2-palmitic and 1-palmitic-2-linoleic acid esters of 3-MCPD were synthesized and evaluated with respect to their acute oral toxicities in Swiss mice. 3-MCPDEs were obtained through the reaction of 3-MCPD and fatty acid chlorides, and their purities and structures were characterized by ultraperformance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS), infrared, 1 H and 13 C spectroscopic analyses. Medial lethal doses of 1-stearic, 1-oleic, 1-linoleic, 1-linoleic-2-palmitic and 1-palmitic-2-linoleic acid esters were 2973.8, 2081.4, 2016.3, 5000 and > 5000 mg kg -1 body weight. For the first time, 3-MCPDEs were observed for their toxic effects in the thymus and lung. In addition, major histopathological changes, as well as blood urea nitrogen and creatinine, were examined for mice fed the five 3-MCPDEs. The results from the present study suggest that the degree of unsaturation, chain length, number of substitution and relative substitution locations of fatty acids might alter the toxicity of 3-MCPDEs. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Reactive Distillation for Esterification of Bio-based Organic Acids

Energy Technology Data Exchange (ETDEWEB)

Fields, Nathan; Miller, Dennis J.; Asthana, Navinchandra S.; Kolah, Aspi K.; Vu, Dung; Lira, Carl T.

2008-09-23

The following is the final report of the three year research program to convert organic acids to their ethyl esters using reactive distillation. This report details the complete technical activities of research completed at Michigan State University for the period of October 1, 2003 to September 30, 2006, covering both reactive distillation research and development and the underlying thermodynamic and kinetic data required for successful and rigorous design of reactive distillation esterification processes. Specifically, this project has led to the development of economical, technically viable processes for ethyl lactate, triethyl citrate and diethyl succinate production, and on a larger scale has added to the overall body of knowledge on applying fermentation based organic acids as platform chemicals in the emerging biorefinery. Organic acid esters constitute an attractive class of biorenewable chemicals that are made from corn or other renewable biomass carbohydrate feedstocks and replace analogous petroleum-based compounds, thus lessening U.S. dependence on foreign petroleum and enhancing overall biorefinery viability through production of value-added chemicals in parallel with biofuels production. Further, many of these ester products are candidates for fuel (particularly biodiesel) components, and thus will serve dual roles as both industrial chemicals and fuel enhancers in the emerging bioeconomy. The technical report from MSU is organized around the ethyl esters of four important biorenewables-based acids: lactic acid, citric acid, succinic acid, and propionic acid. Literature background on esterification and reactive distillation has been provided in Section One. Work on lactic acid is covered in Sections Two through Five, citric acid esterification in Sections Six and Seven, succinic acid in Section Eight, and propionic acid in Section Nine. Section Ten covers modeling of ester and organic acid vapor pressure properties using the SPEAD (Step Potential

Toxicity of nalidixic acid on candida albicans, Saccharomyces cerevisiae, and Kluyveromyces lactis.

Science.gov (United States)

Sobieski, R J; Brewer, A R

1976-03-01

The antibacterial drug nalidixic acid (Nal) can suppress the growth of Candida albicans at levels of the drug normally found in urine. Growth suppression increases as drug levels are increased, and Nal also causes a similar proportional inhibition of the synthesis of all cellular macromolecules. However, growth temperature (25 versus 37 C) and the divalent cations Mg(2+) and Mn(2+) can increase C. albicans resistance to Nal. Also, nitrogen depletion of Candida shows that Nal-treated and untreated cells exhibit no difference in leucine uptake during readaptation to nitrogen. In Nal-treated, nitrogen-starved cells, ribonucleic acid and deoxyribonucleic acid (DNA) biosynthesis are less affected than in unstarved Nal-treated cells, but of the two nucleic acids DNA synthesis is the most affected. Nal-resistant strains of C. albicans exhibit a slight toxicity for macromolecular synthesis. Nal treatment of a synchronized population of Saccharomyces cerevisiae results in an increase in the culture mean doubling time of, at most, 20%, but Nal causes the loss of synchronous cell division. With a synchronized population of Kluyveromyces lactis, Nal causes an increase in the mean doubling time of upwards of 300%, with synchrony of cell division being maintained. It is known that S. cerevisiae asynchronously synthesizes mitochondrial DNA during the cell cycle, whereas with K. lactis it is synchronous. Thus, with C. albicans Nal toxicity is dependent both on the dose and the physiological state of the cell. Furthermore, Nal inhibits growth of yeast with synchronous mitochondrial DNA synthesis more adversely than yeast with asynchronous mitochondrial DNA synthesis.

Toxicity identification evaluation methods for identification of toxicants in refinery effluents

International Nuclear Information System (INIS)

Barten, K.A.; Mount, D.R.; Hackett, J.R.

1993-01-01

During the last five years, the authors have used Toxicity Identification Evaluation (TIE) methods to characterize and identify the source(s) of toxicity in effluents from dozens of municipal and industrial facilities. In most cases, specific chemicals responsible for toxicity have been identified. Although generally successful, the initial experience was that for several refinery effluents, they were able only to qualitatively characterize the presence of organic toxicants; standard toxicant identification procedures were not able to isolate specific organic chemicals. They believe that organic toxicity in these refinery effluents is caused by multiple organic compounds rather than by just a few; evidence for this includes an inability to isolate toxicity in a small number of fractions using liquid chromatography and the presence of very large numbers of compounds in isolated fractions. There is also evidence that the toxicant(s) may be ionic, in that the toxicity of whole effluent and isolated fractions often show increasing toxicity with decreasing pH. Finally, positive-pressure filtration has also reduced toxicity in some samples. In this presentation the authors summarize their experiences with refinery effluents, focusing on typical patterns they have observed and alternative procedures they have used to better understand the nature of these toxicants

Toxicity of binary chemical munition destruction products: methylphosphonic acid, methylphosphinic acid, 2-diisopropylaminoethanol, DF neutralent, and QL neutralent.

Science.gov (United States)

Watson, Rebecca E; Hafez, Ahmed M; Kremsky, Jonathan N; Bizzigotti, George O

2007-01-01

This paper reports the toxicity and environmental impact of neutralents produced from the hydrolysis of binary chemical agent precursor chemicals DF (methylphosphonic difluoride) and QL (2-[bis(1-methylethyl)amino]ethyl ethyl methylphosphonite). Following a literature review of the neutralent mixtures and constituents, basic toxicity tests were conducted to fill data gaps, including acute oral and dermal median lethal dose assays, the Ames mutagenicity test, and ecotoxicity tests. For methylphosphonic acid (MPA), a major constituent of DF neutralent, the acute oral LD(50) in the Sprague-Dawley rat was measured at 1888 mg/kg, and the Ames test using typical tester strains of Salmonella typhimurium and Escherichia coli was negative. The 48-h LC(50) values for pH-adjusted DF neutralent with Daphnia magna and Cyprinodon variegatus were > 2500 mg/L and 1593 mg/L, respectively. The acute oral LD(50) values in the rat for QL neutralent constituents methylphosphinic acid (MP) and 2-diisopropylaminoethanol (KB) were both determined to be 940 mg/kg, and the Ames test was negative for both. Good Laboratory Practice (GLP)-compliant ecotoxicity tests for MP and KB gave 48-h D. magna EC(50) values of 6.8 mg/L and 83 mg/L, respectively. GLP-compliant 96-h C. variegatus assays on MP and KB gave LC(50) values of 73 and 252 mg/L, respectively, and NOEC values of 22 and 108 mg/L. QL neutralent LD(50) values for acute oral and dermal toxicity tests were both > 5000 mg/kg, and the 48-h LD(50) values for D. magna and C. variegatus were 249 and 2500 mg/L, respectively. Using these data, the overall toxicity of the neutralents was assessed.

Sensing and capture of toxic and hazardous gases and vapors by metal-organic frameworks.

Science.gov (United States)

Wang, Hao; Lustig, William P; Li, Jing

2018-03-13

Toxic and hazardous chemical species are ubiquitous, predominantly emitted by anthropogenic activities, and pose serious risks to human health and the environment. Thus, the sensing and subsequent capture of these chemicals, especially in the gas or vapor phase, are of extreme importance. To this end, metal-organic frameworks have attracted significant interest, as their high porosity and wide tunability make them ideal for both applications. These tailorable framework materials are particularly promising for the specific sensing and capture of targeted chemicals, as they can be designed to fit a diverse range of required conditions. This review will discuss the advantages of metal-organic frameworks in the sensing and capture of harmful gases and vapors, as well as principles and strategies guiding the design of these materials. Recent progress in the luminescent detection of aromatic and aliphatic volatile organic compounds, toxic gases, and chemical warfare agents will be summarized, and the adsorptive removal of fluorocarbons/chlorofluorocarbons, volatile radioactive species, toxic industrial gases and chemical warfare agents will be discussed.

Evaluation of different approaches to quantify strong organic acidity and acid-base buffering of organic-rich surface waters in Sweden.

Science.gov (United States)

Köhler, Stephan; Hruska, Jakub; Jönsson, Jörgen; Lövgren, Lars; Lofts, Stephen

2002-11-01

The role of organic acids in buffering pH in surface waters has been studied using a small brownwater stream (26mg L(-1) TOC) draining a forested catchment in Northern Sweden. Under the conditions of elevated pressure of CO2 stream field pH was changed between 3.5 and 6.1 during the acidification and alkalinization experiment. Acid-base characteristics of the natural organic matter were also determined using a high precision potentiometric method for a concentrated sample from the same stream. We compared the predictions from the Windermere Humic Aqueous Model (WHAM Model V), a model derived from the potentiometric titration (diprotic/monoprotic acid model) and a previously derived triprotic acid model which only uses alkalinity and TOC as input variables. The predicted buffering characteristics of all three models are very similar in the pH range 4.5-7 which suggests that during routine analysis alkalinity and TOC are sufficient to give a good estimate of organic acid anion charge contribution in a large range of surface waters. A slightly adjusted version of WHAM V successfully describes the organic charge contribution in a large number of sampled surface water lakes, which were previously used to calibrate the triprotic model.

Quinolinic Acid, an Endogenous Molecule Combining Excitotoxicity, Oxidative Stress and Other Toxic Mechanisms

Directory of Open Access Journals (Sweden)

Verónica Pérez-De La Cruz

2012-01-01

Full Text Available Quinolinic acid (QUIN, an endogenous metabolite of the kynurenine pathway, is involved in several neurological disorders, including Huntington's disease, Alzheimer's disease, schizophrenia, HIV associated dementia (HAD etc. QUIN toxicity involves several mechanisms which trigger various metabolic pathways and transcription factors. The primary mechanism exerted by this excitotoxin in the central nervous system (CNS has been largely related with the overactivation of N-methyl-D-aspartate receptors and increased cytosolic Ca 2+ concentrations, followed by mitochondrial dysfunction, cytochrome c release, ATP exhaustion, free radical formation and oxidative damage. As a result, this toxic pattern is responsible for selective loss of middle size striatal spiny GABAergic neurons and motor alterations in lesioned animals. This toxin has recently gained attention in biomedical research as, in addition to its proven excitotoxic profile, a considerable amount of evidence suggests that oxidative stress and energetic disturbances are major constituents of its toxic pattern in the CNS. Hence, this profile has changed our perception of how QUIN-related disorders combine different toxic mechanisms resulting in brain damage. This review will focus on the description and integration of recent evidence supporting old and suggesting new mechanisms to explain QUIN toxicity.

α-lipoic acid inhibits oxidative stress in testis and attenuates testicular toxicity in rats exposed to carbimazole during embryonic period

Directory of Open Access Journals (Sweden)

P. Prathima

Full Text Available The aim of this study was to evaluate the probable protective effect of α-lipoic acid against testicular toxicity in rats exposed to carbimazole during the embryonic period. Time-mated pregnant rats were exposed to carbimazole from the embryonic days 9–21. After completion of the gestation period, all the rats were allowed to deliver pups and weaned. At postnatal day 100, F1 male pups were assessed for the selected reproductive endpoints. Gestational exposure to carbimazole decreased the reproductive organ indices, testicular daily sperm count, epididymal sperm variables viz., sperm count, viable sperm, motile sperm and HOS-tail coiled sperms. Significant decrease in the activity levels of 3β- and 17β-hydroxysteroid dehydrogenases and expression of StAR mRNA levels with a significant increase in the total cholesterol levels were observed in the testis of experimental rats over the controls. These events were also accompanied by a significant reduction in the serum testosterone levels in CBZ exposed rats, indicating reduced steroidogenesis. In addition, the deterioration of the testicular architecture and reduced fertility ability were noticed in the carbimazole exposed rats. Significant reduction in the activity levels of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and reduced glutathione content with a significant increase in the levels of lipid peroxidation were observed in the testis of carbimazole exposed rats over the controls. Conversely, supplementation of α-lipoic acid (70 mg/Kg bodyweight ameliorated the male reproductive health in rats exposed to carbimazole during the embryonic period as evidenced by enhanced reproductive organ weights, selected sperm variables, testicular steroidogenesis, and testicular enzymatic and non-enzymatic antioxidants. To conclude, diminished testicular antioxidant balance associated with reduced spermatogenesis and steroidogenesis might be responsible

Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

International Nuclear Information System (INIS)

Sevigny, J.H.; Lintott, D.; Wrubleski, R.M.; Drury, C.R.

1997-01-01

The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox R toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox R toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox R toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent

Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

Energy Technology Data Exchange (ETDEWEB)

Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada); Lintott, D. [HydroQual Consultants, Inc., Calgary, AB (Canada); Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

1997-12-31

The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox{sup R} toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox{sup R} toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox{sup R} toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent.

Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.

Science.gov (United States)

Bobbitt, N Scott; Mendonca, Matthew L; Howarth, Ashlee J; Islamoglu, Timur; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

2017-06-06

Owing to the vast diversity of linkers, nodes, and topologies, metal-organic frameworks can be tailored for specific tasks, such as chemical separations or catalysis. Accordingly, these materials have attracted significant interest for capture and/or detoxification of toxic industrial chemicals and chemical warfare agents. In this paper, we review recent experimental and computational work pertaining to the capture of several industrially-relevant toxic chemicals, including NH 3 , SO 2 , NO 2 , H 2 S, and some volatile organic compounds, with particular emphasis on the challenging issue of designing materials that selectively adsorb these chemicals in the presence of water. We also examine recent research on the capture and catalytic degradation of chemical warfare agents such as sarin and sulfur mustard using metal-organic frameworks.

Anaerobic biodegradability and toxicity of complex or toxicant wastewater

International Nuclear Information System (INIS)

Wills Betancur, B.A.

1995-01-01

As a first approximation to wastewater classification in susceptibility terms to treatment by anaerobic biological system, anaerobic biodegradability trials are accomplished to leached of sanitary landfill, to wastewater of coffee grain wet treatment plant and to wastewater of fumaric acid recuperation plant. In the last Plant, anaerobic toxicity trials and lethal toxicity on the Daphnia pulex micro-crustacean are made too. Anaerobic biological trials are made continuing the Wageningen University (Holland) Methodology (1.987). Lethal toxicity biological trials are made following the Standard Methods for the Examination of Water and Wastewater(18th edition, 1992). In development of this investigation project is found that fumaric acid recuperation plant leached it has a low anaerobic biodegradability, a high anaerobic toxicity and a high lethal toxicity over Daphnia pulex, for such reasons this leached is cataloged as complex and toxic wastewater. The other hand, wastewater of coffee grain wet treatment plant and wastewater of sanitary landfill they are both highly biodegradability and not-toxic, for such reasons these wastewaters are cataloged as susceptible to treatment by anaerobic biological system

Toxicity of two imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], to standard aquatic test organisms: Role of acetone in the induced toxicity.

Science.gov (United States)

Tsarpali, Vasiliki; Dailianis, Stefanos

2015-07-01

The main goal of this study was to investigate the toxicity of the imidazolium-based ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium tetrafluoroborate) and [omim][BF4] (1-octyl-3-methylimidazolium tetrafluoroborate), in battery of standard aquatic toxicity test organisms. Specifically, exposure of the algae Scenedesmus rubescens, crustaceans Thamnocephalus platyurus and Artemia franciscana, rotifers Brachionus calyciflorus and Brachionus plicatilis and bivalve Mytilus galloprovincialis to different concentrations of [bmim][BF4], [omim][BF4] and/or a binary mixture of [bmim][BF4]-[omim][BF4] (1:1) with or without acetone (carrier solvent), revealed that solvent can differentially mediate ILs' toxic profile. Acetone's ability to differentially affect ILs' cation's alkyl chain length, as well as the hydrolysis of [BF4(-)] anions was evident. Given that the toxic potency of the tested ILs seemed to be equal or even higher (in some cases) than those of conventional organic solvents, the present study revealed that the characterization of imidazolium-based ILs as "green solvents" should not be generalized, at least in case of their natural occurrence in mixtures with organic solvents, such as acetone. Copyright © 2015 Elsevier Inc. All rights reserved.

Uranium leaching using mixed organic acids produced by Aspergillus niger

International Nuclear Information System (INIS)

Yong-dong Wang; Guang-yue Li; De-xin Ding; Zhi-xiang Zhou; Qin-wen Deng; Nan Hu; Yan Tan

2013-01-01

Both of culture temperature and pH value had impacts on the degree of uranium extraction through changing types and concentrations of mixed organic acids produced by Aspergillus niger, and significant interactions existed between them though pH value played a leading role. And with the change of pH value of mixed organic acids, the types and contents of mixed organic acids changed and impacted on the degree of uranium extraction, especially oxalic acid, citric acid and malic acid. The mean degree of uranium extraction rose to peak when the culture temperature was 25 deg C (76.14 %) and pH value of mixed organic acids was 2.3 (82.40 %) respectively. And the highest one was 83.09 %. The optimal culture temperature (25 deg C) of A. niger for uranium leaching was different from the most appropriate growing temperature (37 deg C). (author)

Effect of natural organic matter on the photo-induced toxicity of titanium dioxide nanoparticles.

Science.gov (United States)

Wormington, Alexis M; Coral, Jason; Alloy, Matthew M; Delmarè, Carmen L; Mansfield, Charles M; Klaine, Stephen J; Bisesi, Joseph H; Roberts, Aaron P

2017-06-01

Nano-titanium dioxide (TiO 2 ) is the most widely used form of nanoparticles in commercial industry and comes in 2 main configurations: rutile and anatase. Rutile TiO 2 is used in ultraviolet (UV) screening applications, whereas anatase TiO 2 crystals have a surface defect that makes them photoreactive. There are numerous reports in the literature of photo-induced toxicity to aquatic organisms following coexposure to anatase nano-TiO 2 and UV. All natural freshwater contains varying amounts of natural organic matter (NOM), which can drive UV attenuation and quench reactive oxygen species (ROS) in aquatic ecosystems. The present research examined how NOM alters the photo-induced toxicity of anatase nano-TiO 2 . Daphnia magna neonates were coexposed to NOM and photoexcited anatase nano-TiO 2 for 48 h. Natural organic matter concentrations as low as 4 mg/L reduced anatase nano-TiO 2 toxicity by nearly 100%. These concentrations of NOM attenuated UV by <10% in the exposure system. However, ROS production measured using a fluorescence assay was significantly reduced in a NOM concentration--dependent manner. Taken together, these data suggest that NOM reduces anatase nano-TiO 2 toxicity via an ROS quenching mechanism and not by attenuation of UV. Environ Toxicol Chem 2017;36:1661-1666. © 2016 SETAC. © 2016 SETAC.

Recovery of Pyruvic Acid using Tri-n-butylamine Dissolved in Non-Toxic Diluent (Rice Bran Oil)

Science.gov (United States)

Pal, Dharm; Keshav, Amit

2016-04-01

An attempt has been made to investigate the effectiveness of the vegetable oil based biocompatible solvent for the separation of pyruvic acid from fermentation broth, by using rice bran oil as natural, non-toxic diluent. Reactive extraction of pyruvic acid (0.1-0.5 k mol/m3) from aqueous solutions has been studied using tri-n-butylamine (TBA; 10-70 %) as an extractant dissolved in non toxic rice bran oil at T = 30 ± 1 °C. Results were presented in terms of distribution coefficient (Kd), extraction efficiency (E %), loading ratio (Z), and complexation constant (\\varphi_{α β }). Extraction equilibrium was interpreted using mass action modeling approach. Based on the extent of loading (Z < 0.5) only (1:1), pyruvic acid: TBA complex was proposed. Equilibrium complexation constant was evaluated to 1.22 m3/k mol. Results obtained are useful in understanding the extraction mechanism.

A Broad Spectrum Catalytic System for Removal of Toxic Organics from Water by Deep Oxidation - Final Report

Energy Technology Data Exchange (ETDEWEB)

Sen, Ayusman

2000-12-01

A most pressing need for the DOE environmental management program is the removal of toxic organic compounds present in groundwater and soil at specific DOE sites. While several remediation procedures have been proposed, they suffer from one or more drawbacks. The objective of the present research was to develop new catalytic procedures for the removal of toxic organic compounds from the environment through their deep oxidation to harmless products. In water, metallic palladium was found to catalyze the deep oxidation of a wide variety of toxic organic compounds by dioxygen at 80-90 C in the presence of carbon monoxide or dihydrogen. Several classes of organic compounds were examined: benzene, phenol and substituted phenols, nitro and halo organics, organophosphorus, and organosulfur compounds. In every case, deep oxidation to carbon monoxide, carbon dioxide, and water occurred in high yields, resulting in up to several hundred turnovers over a 24 hour period. For substrates susceptible to hydrogenation, the conversions were generally high with dihydrogen than with carbon monoxide. It is clear from the results obtained that we have discovered an exceptionally versatile catalytic system for the deep oxidation of toxic organic compounds in water. This system possesses several attractive features not found simultaneously in other reported systems. These are (a) the ability to directly utilize dioxygen as the oxidant, (b) the ability to carry out the deep oxidation of a particularly wide range of functional organics, and (c) the ease of recovery of the catalyst by simple filtration.

Dynamics of three organic acids (malic, acetic and succinic acid) in sunflower exposed to cadmium and lead.

Science.gov (United States)

Niu, Zhixin; Li, Xiaodong; Sun, Lina; Sun, Tieheng

2013-01-01

Sunflower (Helianthus annuus L.) has been considered as a good candidate for bioaccumulation of heavy metals. In the present study, sunflower was used to enrich the cadmium and lead in sand culture during 90 days. Biomass, Cd and Pb uptake, three organic acids and pH in cultures were investigated. Results showed that the existence of Cd and Pb showed different interactions on the organic acids exudation. In single Cd treatments, malic and acetic acids in Cd10 showed an incremental tendency with time. In the mixed treatments of Cd and Pb, malic acids increased when 10 and 40 mg x L(-1) Cd were added into Pb50, but acetic acids in Pb50 were inhibited by Cd addition. The Cd10 supplied in Pb10 stimulated the secretion of malic and succinic acids. Moreover, the Cd or Pb uptake in sunflower showed various correlations with pH and some organic acids, which might be due to the fact that the Cd and Pb interfere with the organic acids secretion in rhizosphere of sunflower, and the changes of organic acids altered the form and bioavailability of Cd and Pb in cultures conversely.

Use of organic acids in acne and skin discolorations therapy

Directory of Open Access Journals (Sweden)

Alicja Kapuścińska

2015-03-01

Full Text Available Acne is one of the most frequent skin disorders that occurs in puberty, but often adults also have acne. The most important factors responsible for acne are elevated production of sebum by hyperactive sebaceous glands and blockage of the follicle because of hyperkeratosis [14]. The third etiopathogenic factor of acne is excessive microflora reproduction [8]. The most significant bacterium that is responsible for formation of skin lesions is Propionibacterium acnes, a rod-shaped Gram-positive and aerotolerant anaerobic bacterium. It is estimated that P. acnes is responsible for acne in approximately 80% of people aged 11 to 30 [27,40]. Even healed skin lesions can often cause skin discolorations and scar formation [51]. Exfoliating chemical substances that are commonly used in dermatology and cosmetology are organic acids. Exfoliating treatment using organic acids is called “chemical peeling” and consists of controlled application of those substances on the skin [38]. The depth of exfoliation depends on organic acid concentration, type of substance and contact time with the skin [41]. Using exfoliating agents seems to be helpful in excessive keratinization – one of several factors responsible for acne. Moreover, epidermis exfoliation is a popular method of removing skin discoloration [22]. Considering chemical structure, exfoliating substances that are most often used in cosmetology contain alpha-hydroxyacids (glycolic acid, lactic acid, mandelic acid and citric acid, beta-hydroxyacids (salicylic acid and other organic acids, such as trichloroacetic acid and pyruvic acid [47]. In this article, a literature review of use of organic acids in acne and skin discoloration therapy is presented.

Green synthesis of low-toxicity graphene-fulvic acid with an open band gap enhances demethylation of methylmercury.

Science.gov (United States)

Hu, Xiangang; Mu, Li; Lu, Kaicheng; Kang, Jia; Zhou, Qixing

2014-06-25

The demethylation of methylmercury has received substantial attention. Here, a novel chemical method for the demethylation of methylmercury is proposed. The low-toxicity graphene-fulvic acid (FA, a ubiquitous material in the environment) was synthesized without the use of a chemical reagent. The hybridized graphene-FA presented an indirect open band gap of 2.25-2.87 eV as well as adequate aqueous dispersion. More importantly, the hybridized graphene-FA exhibited 6- and 10-fold higher photocatalytic efficiencies for the demethylation of methylmercury than FA and free FA with graphene, respectively. This result implies that immobilized, rather than free, FA accelerated the catalysis. Furthermore, inorganic mercuric ion, elemental mercury, and mercuric oxide were identified as the primary demethylation products. For free FA with graphene, graphene quenches the excited-state FA, inhibiting the demethylation by electron transfer. In contrast, the graphene of the self-assembled graphene-FA serves as an electron reservoir, causing electron-hole pair separation. Graphene-FA showed a negligible toxicity toward microalgae compared to graphene. The above results reveal that the green synthesis of graphene and organic molecules is a convenient strategy for obtaining effective cocatalysts.

Flavor Compounds in Pixian Broad-Bean Paste: Non-Volatile Organic Acids and Amino Acids

Directory of Open Access Journals (Sweden)

Hongbin Lin

2018-05-01

Full Text Available Non-volatile organic acids and amino acids are important flavor compounds in Pixian broad-bean paste, which is a traditional Chinese seasoning product. In this study, non-volatile organic acids, formed in the broad-bean paste due to the metabolism of large molecular compounds, are qualitatively and quantitatively determined by high-performance liquid chromatography (HPLC. Amino acids, mainly produced by hydrolysis of soybean proteins, were determined by the amino acid automatic analyzer. Results indicated that seven common organic acids and eighteen common amino acids were found in six Pixian broad-bean paste samples. The content of citric acid was found to be the highest in each sample, between 4.1 mg/g to 6.3 mg/g, and malic acid were between 2.1 mg/g to 3.6 mg/g ranked as the second. Moreover, fumaric acid was first detected in fermented bean pastes albeit with a low content. For amino acids, savory with lower sour taste including glutamine (Gln, glutamic acid (Glu, aspartic acid (Asp and asparagines (Asn were the most abundant, noted to be 6.5 mg/g, 4.0 mg/g, 6.4 mg/g, 4.9 mg/g, 6.2 mg/g and 10.2 mg/g, and bitter taste amino acids followed. More importantly, as important flavor materials in Pixian broad-bean paste, these two groups of substances are expected to be used to evaluate and represent the flavor quality of Pixian broad-bean paste. Moreover, the results revealed that citric acid, glutamic acid, methionine and proline were the most important flavor compounds. These findings are agreat contribution for evaluating the quality and further assessment of Pixian broad-bean paste.

Flavor Compounds in Pixian Broad-Bean Paste: Non-Volatile Organic Acids and Amino Acids.

Science.gov (United States)

Lin, Hongbin; Yu, Xiaoyu; Fang, Jiaxing; Lu, Yunhao; Liu, Ping; Xing, Yage; Wang, Qin; Che, Zhenming; He, Qiang

2018-05-29

Non-volatile organic acids and amino acids are important flavor compounds in Pixian broad-bean paste, which is a traditional Chinese seasoning product. In this study, non-volatile organic acids, formed in the broad-bean paste due to the metabolism of large molecular compounds, are qualitatively and quantitatively determined by high-performance liquid chromatography (HPLC). Amino acids, mainly produced by hydrolysis of soybean proteins, were determined by the amino acid automatic analyzer. Results indicated that seven common organic acids and eighteen common amino acids were found in six Pixian broad-bean paste samples. The content of citric acid was found to be the highest in each sample, between 4.1 mg/g to 6.3 mg/g, and malic acid were between 2.1 mg/g to 3.6 mg/g ranked as the second. Moreover, fumaric acid was first detected in fermented bean pastes albeit with a low content. For amino acids, savory with lower sour taste including glutamine (Gln), glutamic acid (Glu), aspartic acid (Asp) and asparagines (Asn) were the most abundant, noted to be 6.5 mg/g, 4.0 mg/g, 6.4 mg/g, 4.9 mg/g, 6.2 mg/g and 10.2 mg/g, and bitter taste amino acids followed. More importantly, as important flavor materials in Pixian broad-bean paste, these two groups of substances are expected to be used to evaluate and represent the flavor quality of Pixian broad-bean paste. Moreover, the results revealed that citric acid, glutamic acid, methionine and proline were the most important flavor compounds. These findings are agreat contribution for evaluating the quality and further assessment of Pixian broad-bean paste.

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

Energy Technology Data Exchange (ETDEWEB)

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

2011-12-15

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

Effect of malachite green toxicity on non target soil organisms.

Science.gov (United States)

Gopinathan, R; Kanhere, J; Banerjee, J

2015-02-01

Although malachite green (MG), is banned in Europe and US for its carcinogenic and teratogenic effect, the dye being cheap, is persistently used in various countries for fish farming, silk, dye, leather and textile industries. Current research, however, fails to elucidate adequate knowledge concerning the effects of MG in our ecosystem. In the present investigation, for the first time, an attempt has been made to study the effects of MG on soil biota by testing Bacillus subtilis, Azotobacter chroococcum, Saccharomyces cerevisiae, Penicillium roqueforti, Eisenia fetida and seeds of three crop plants of different families. Various tests were conducted for determining cytotoxicity, genotoxicity, acute toxicity, morphological and germination effect. Our data confirmed MG toxicity on fungi and bacteria (gram positive and gram negative organisms) showing elevated level of ROS. Genotoxicity caused in the microorganisms was detected by DNA polymorphism and fragmentation. Also, scanning electron microscopy data suggests that the inhibitory effect of MG to these beneficial microbes in the ecosystem might be due to pore formation in the cell and its eventual disruption. Filter paper and artificial soil test conducted on earthworms demonstrated a LC 50 of 2.6 mg cm(-2) and 1.45 mg kg(-1) respectively with severe morphological damage. However, seed germination of Mung bean, Wheat and Mustard was found to be unaffected in presence of MG up to 100 mL(-1) concentration. Thus, understanding MG toxicity in non target soil organisms and emphasis on its toxicological effects would potentially explicate its role as an environmental contaminant. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of the role of in situ generated (E)-2,4-diene-valproic acid in the toxicity of valproic acid and (E)-2-ene-valproic acid in sandwich-cultured rat hepatocytes

Energy Technology Data Exchange (ETDEWEB)

Surendradoss, Jayakumar; Chang, Thomas K.H.; Abbott, Frank S., E-mail: frank.abbott@ubc.ca

2012-11-01

Valproic acid (VPA) undergoes cytochrome P450-mediated desaturation to form 4-ene-VPA, which subsequently yields (E)-2,4-diene-VPA by β-oxidation. Another biotransformation pathway involves β-oxidation of VPA to form (E)-2-ene-VPA, which also generates (E)-2,4-diene-VPA by cytochrome P450-mediated desaturation. Although the synthetic form of (E)-2,4-diene-VPA is more hepatotoxic than VPA as shown in various experimental models, there is no conclusive evidence to implicate the in situ generated (E)-2,4-diene-VPA in VPA hepatotoxicity. The present study investigated the effects of modulating the in situ formation of (E)-2,4-diene-VPA on markers of oxidative stress (formation of 2′,7′-dichlorofluorescein; DCF), steatosis (accumulation of BODIPY 558/568 C{sub 12}), necrosis (release of lactate dehydrogenase; LDH), and on cellular total glutathione (GSH) levels in sandwich-cultured rat hepatocytes treated with VPA or (E)-2-ene-VPA. Treatment with either of these chemicals alone increased each of the toxicity endpoints. In VPA-treated hepatocytes, (E)-2,4-diene-VPA was detected only at trace levels, even after phenobarbital (PB) pretreatment and there was no effect on the toxicity of VPA. Furthermore, pretreatment with a cytochrome P450 enzyme inhibitor, 1-aminobenzotriazole (1-ABT), did not influence the extent of VPA toxicity in both PB-pretreated and vehicle-pretreated hepatocytes. However, in (E)-2-ene-VPA-treated hepatocytes, PB pretreatment greatly enhanced the levels of (E)-2,4-diene-VPA and this was accompanied by a further enhancement of the effects of (E)-2-ene-VPA on DCF formation, BODIPY accumulation, LDH release, and GSH depletion. Pretreatment with 1-ABT reduced the concentrations of (E)-2,4-diene-VPA and the extent of (E)-2-ene-VPA toxicity; however, this occurred in PB-pretreated hepatocytes, but not in control hepatocytes. In conclusion, in situ generated (E)-2,4-diene-VPA is not responsible for the hepatocyte toxicity of VPA, whereas it

Amino acid sequence and biological characterization of BlatPLA₂, a non-toxic acidic phospholipase A₂ from the venom of the arboreal snake Bothriechis lateralis from Costa Rica.

Science.gov (United States)

Van der Laat, Marco; Fernández, Julián; Durban, Jordi; Villalobos, Eva; Camacho, Erika; Calvete, Juan J; Lomonte, Bruno

2013-10-01

Bothriechis is considered a monophyletic, basal genus of arboreal Neotropical pitvipers distributed across Middle America. The four species found in Costa Rica (B. lateralis, B. schlegeli, B. nigroviridis, B. supraciliaris) differ in their venom proteomic profiles, suggesting that different Bothriechis taxa have evolved diverse trophic strategies. In this study, we isolated a phospholipase A₂ (PLA₂) from B. lateralis venom, aiming at increasing our knowledge on the structural and functional characteristics of group II acidic PLA₂s, whose toxic actions are generally more restricted than those displayed by basic PLA₂s. The new acidic enzyme, BlatPLA₂, occurs as a monomer of 13,917 Da, in contrast to many basic group II PLA₂s which associate into dimers and often display myotoxicity and/or neurotoxicity. Its amino acid sequence of 122 residues predicts an isoelectric point of 4.7, and displays significant differences with previously characterized acidic PLA₂s, with which it shows a maximum sequence identity of 78%. BlatPLA₂ is catalytically active but appears to be devoid of major toxic activities, lacking intravenous or intracerebroventricular lethality, myotoxicity, in vitro anticoagulant activity, and platelet aggregation or inhibition effects. Phylogenetic relationships with similar group II enzymes suggest that BlatPLA₂ may represent a basal sequence to other acidic PLA₂s. Due to the metabolic cost of venom protein synthesis, the presence of a relatively abundant (9%) but non-toxic component is somewhat puzzling. Nevertheless, we hypothesize that BlatPLA₂ could have a role in the pre-digestion of prey, possibly having retained characteristics of ancestral PLA₂s without evolving towards potent toxicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Organic acid excretion in Penicillium ochrochloron increases with ambient pH

Directory of Open Access Journals (Sweden)

Pamela eVrabl

2012-04-01

Full Text Available Despite being of high biotechnological relevance, many aspects of organic acid excretion in filamentous fungi like the influence of ambient pH are still insufficiently understood. While the excretion of an individual organic acid may peak at a certain pH value, the few available studies investigating a broader range of organic acids indicate that total organic acid excretion rises with increasing external pH.We hypothesized that this phenomenon might be a general response of filamentous fungi to increased ambient pH. If this is the case, the observation should be widely independent of the organism, growth conditions or experimental design and might therefore be a crucial key point in understanding the function and mechanisms of organic acid excretion in filamentous fungi.In this study we explored this hypothesis using ammonium limited chemostat cultivations (pH 2-7, and ammonium or phosphate limited bioreactor batch cultivations (pH 5 and 7. Two strains of Penicillium ochrochloron were investigated differing in the spectrum of excreted organic acids.Confirming our hypothesis, the main result demonstrated that organic acid excretion in P. ochrochloron was enhanced at high external pH levels compared to low pH levels independent of the tested strain, nutrient limitation and cultivation method. We discuss these findings against the background of three hypotheses explaining organic acid excretion in filamentous fungi, i.e. overflow metabolism, charge balance and aggressive acidification hypothesis.

Organic compounds as corrosion inhibitors for mild steel in acidic media: correlation between inhibition efficiency and chemical structure

Energy Technology Data Exchange (ETDEWEB)

Elias, Elizandra C.S.; Chrisman, Erika C.A.N. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Escola de Quimica

2009-12-19

The use of inhibitors for mild steels corrosion control which are in contact with aggressive environment is an accepted practice in acid treatment of oil-wells. Organic compounds have been studied to evaluate their corrosion inhibition potential. Film-forming corrosion inhibitors, commonly used to protect oil-field equipment, can be absorbed on the steel surface to give structurally ordered layers. Therefore, the electrons should act as an important role for this adsorption. Studies reveal that organic compounds show significant inhibition efficiency. For this purpose, their molecules should contain N, O and S heteroatoms in various functional groups, long hydrocarbon linear or branched radical and anion and cation active components. However, most of these compounds are not only expensive but also toxic to living beings. According to the 'Green Chemistry' rules, corrosion inhibitors based on organic compounds should be cheap, with low toxicity and have high inhibition efficiency. In this study, the effects of some organic compounds with different groups such as amide, ether, phenyldiamine, anime and aminophenol on the corrosion behavior of mild steel in acidic media have been investigated. The experimental data were obtained by gravimetric measurements. The results show that these compounds reveal a promising corrosion inhibition where phenyldiamine is the most efficient. The effect of molecular structure on the corrosion inhibition efficiency was investigated by semi-empirical quantum chemical calculations. The electronic properties such as highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels, and LUMO-HOMO energy gap orbital density were calculated. The relations between the inhibition efficiency and some quantum parameters are discussed and correlations are proposed. The highest values for the HOMO densities were found in the vicinity nitrogen atom, indicating that it is the most probable adsorption center

Application of toxicity testing in the evaluation of reclamation options for oil sands fine tails

International Nuclear Information System (INIS)

Nelson, L.R.; MacKinnon, M.; Gulley, J.R.

1993-01-01

The hot water process for the extraction of bitumen from oil sands leads to the production of large volumes of wastewater and the formation of a large inventory of fine clay tailings. This fine tailings material and its associated water are acutely toxic to various aquatic test organisms during bioassays. An overview is presented of toxicity testing at Syncrude and Suncor, the application of toxicity testing to fine tailings management, and the role in reclamation planning. The main acutely toxic component of the tailings is the polar organic acid fraction, specifically naphthanates. These naphthanates are readily degraded biologically by indigenous microbial populations. Toxicity testing is aimed at assessing the degree of both acute and chronic toxicity and the long term potential for the input of toxins into the environment from various proposed reclamation measures. 28 refs., 6 figs., 2 tabs

Organic Acids Regulation of Chemical-Microbial Phosphorus Transformations in Soils.

Science.gov (United States)

Menezes-Blackburn, Daniel; Paredes, Cecilia; Zhang, Hao; Giles, Courtney D; Darch, Tegan; Stutter, Marc; George, Timothy S; Shand, Charles; Lumsdon, David; Cooper, Patricia; Wendler, Renate; Brown, Lawrie; Blackwell, Martin; Wearing, Catherine; Haygarth, Philip M

2016-11-01

We have used an integrated approach to study the mobility of inorganic phosphorus (P) from soil solid phase as well as the microbial biomass P and respiration at increasing doses of citric and oxalic acid in two different soils with contrasting agronomic P status. Citric or oxalic acids significantly increased soil solution P concentrations for doses over 2 mmol kg -1 . However, low organic acid doses (<2 mmol kg -1 ) were associated with a steep increase in microbial biomass P, which was not seen for higher doses. In both soils, treatment with the tribasic citric acid led to a greater increase in soil solution P than the dibasic oxalic acid, likely due to the rapid degrading of oxalic acids in soils. After equilibration of soils with citric or oxalic acids, the adsorbed-to-solution distribution coefficient (K d ) and desorption rate constants (k -1 ) decreased whereas an increase in the response time of solution P equilibration (T c ) was observed. The extent of this effect was shown to be both soil and organic acid specific. Our results illustrate the critical thresholds of organic acid concentration necessary to mobilize sorbed and precipitated P, bringing new insight on how the exudation of organic acids regulate chemical-microbial soil phosphorus transformations.

Processing of Unsaturated Organic Acid Aerosols by Ozone

Science.gov (United States)

Aloisio, S.; Donaldson, D. J.; Eliason, T. L.; Cziczo, D.; Vaida, V.

2002-05-01

We present results of in-situ studies of the oxidative "processing" of organic aerosols composed of unsaturated organic compounds. Aerosol samples of 2-octenoic acid and undecylenic acid were exposed to approx. 10 mbar ozone in a room temperature, atmospheric pressure flow tube reactor. In-situ spectroscopic probing of the reaction mixture, as well as GC-MS analysis of the flow tube effluent, shows evidence of efficient oxidation of double bonds in the organic species, with production of gas-phase and aerosol phase ozonolysis products.

Environmental, genetic and cellular toxicity of tenuazonic acid ...

African Journals Online (AJOL)

Alternaria alternata, an important pathogen of many plants, produces tenuazonic acid (TeA) with bioactivity to microbes, plants and animals. TeA is one of the main mycotoxin to humans and other organisms. Using Chlamydomonas reinhardtii, Vicia faba root tip and three mammalian normal cell lines as target materials, ...

Dietary preferences of weaned piglets offered diets containing organic acids

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K. PARTANEN

2008-12-01

Full Text Available A preference test and a performance trial were carried out to examine weaned piglets’ feed intake response to diets containing either lactic acid,formic acid,calcium formate,or sodium benzoate (8 g kg-1 feed.In Experiment 1, throughout a 21-d post-weaning period,30 entire litters (306 piglets weaned at the age of 30 d were allowed to choose between two organic-acid-supplemented diets. All of the four different organic-acid-supplemented diets were tested in pairs against each other,and the six possible combinations were lactic acid +formic acid,lactic acid +calcium formate,lactic acid + sodium benzoate,formic acid +calcium formate,formic acid +sodium benzoate,and calcium for-mate +sodium benzoate.Piglets preferred diets supplemented with sodium benzoate to ones supplemented with formic acid or calcium formate.The acceptability of diets supplemented with lactic acid,formic acid,or calcium formate was similar.In Experiment 2,until the age of 58 d,60 piglets from 10 litters weaned at the age of 28 or 38 d were fed non-acidified diets or ones supplemented with lactic acid,formic acid,calcium formate,or sodium benzoate.Feed consumption did not differ between piglets fed non-acidified and those fed organic-acid-supplemented diets. Growth performance was reduced by dietary calcium formate supplementation, while the performance of piglets fed other organic-acid-supplemented diets did not differ significantly from those fed the non-acidified control diet.The frequency of post-weaning diarrhoea was highest in piglets fed diets supplemented with calcium formate and lowest in piglets fed diets supplemented with formic acid.;

Multiple functions of the crustacean gill: osmotic/ionic regulation, acid-base balance, ammonia excretion, and bioaccumulation of toxic metals

Science.gov (United States)

Henry, Raymond P.; Lucu, Čedomil; Onken, Horst; Weihrauch, Dirk

2012-01-01

The crustacean gill is a multi-functional organ, and it is the site of a number of physiological processes, including ion transport, which is the basis for hemolymph osmoregulation; acid-base balance; and ammonia excretion. The gill is also the site by which many toxic metals are taken up by aquatic crustaceans, and thus it plays an important role in the toxicology of these species. This review provides a comprehensive overview of the ecology, physiology, biochemistry, and molecular biology of the mechanisms of osmotic and ionic regulation performed by the gill. The current concepts of the mechanisms of ion transport, the structural, biochemical, and molecular bases of systemic physiology, and the history of their development are discussed. The relationship between branchial ion transport and hemolymph acid-base regulation is also treated. In addition, the mechanisms of ammonia transport and excretion across the gill are discussed. And finally, the toxicology of heavy metal accumulation via the gill is reviewed in detail. PMID:23162474

Sugars, organic acids, minerals and lipids in jabuticaba

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Annete de Jesus Boari Lima

2011-06-01

Full Text Available The aim of this work was to determine the sugar, organic acid and mineral compositions of the whole fruit and fractions (skin, pulp and seed of the Paulista (Plinia cauliflora and Sabará (Plinia jaboticaba jabuticaba tree genotypes, as well as the oil compositions of their skin and seeds. High levels of sugar, especially fructose, followed by glucose and sucrose, were encountered in the fruit. In the Paulista genotype, higher levels of total and reducing sugars were found in the pulp and skin, which was not observed when comparing the whole fruit of both genotypes. Five organic acids were found in the whole fruit and in the fractions of the two jabuticaba genotypes in quantitative order: citric acid > succinic acid > malic acid > oxalic acid > acetic acid. Potassium was the most abundant mineral found. This fruit was also shown to be rich in magnesium, phosphorus, calcium and copper. The seed oil had nearly the same constitution as the oil extracted from the skin in both genotypes and the major compounds were an unidentified phytosterol, palmitic, linoleic and oleic acids, and squalene.

Pretreatment by low-dose fibrates protects against acute free fatty acid-induced renal tubule toxicity by counteracting PPARα deterioration

International Nuclear Information System (INIS)

Takahashi, Kyoko; Kamijo, Yuji; Hora, Kazuhiko; Hashimoto, Koji; Higuchi, Makoto; Nakajima, Takero; Ehara, Takashi; Shigematsu, Hidekazu; Gonzalez, Frank J.; Aoyama, Toshifumi

2011-01-01

Development of a preventive strategy against tubular damage associated with proteinuria is of great importance. Recently, free fatty acid (FFA) toxicities accompanying proteinuria were found to be a main cause of tubular damage, which was aggravated by insufficiency of peroxisome proliferator-activated receptor alpha (PPARα), suggesting the benefit of PPARα activation. However, an earlier study using a murine acute tubular injury model, FFA-overload nephropathy, demonstrated that high-dose treatment of PPARα agonist (0.5% clofibrate diet) aggravated the tubular damage as a consequence of excess serum accumulation of clofibrate metabolites due to decreased kidney elimination. To induce the renoprotective effects of PPARα agonists without drug accumulation, we tried a pretreatment study using low-dose clofibrate (0.1% clofibrate diet) using the same murine model. Low-dose clofibrate pretreatment prevented acute tubular injuries without accumulation of its metabolites. The tubular protective effects appeared to be associated with the counteraction of PPARα deterioration, resulting in the decrease of FFAs influx to the kidney, maintenance of fatty acid oxidation, diminution of intracellular accumulation of undigested FFAs, and attenuation of disease developmental factors including oxidative stress, apoptosis, and NFκB activation. These effects are common to other fibrates and dependent on PPARα function. Interestingly, however, clofibrate pretreatment also exerted PPARα-independent tubular toxicities in PPARα-null mice with FFA-overload nephropathy. The favorable properties of fibrates are evident when PPARα-dependent tubular protective effects outweigh their PPARα-independent tubular toxicities. This delicate balance seems to be easily affected by the drug dose. It will be important to establish the appropriate dosage of fibrates for treatment against kidney disease and to develop a novel PPARα activator that has a steady serum concentration regardless of

Long-term toxicity assessment of soils in a recovered area affected by a mining spill

International Nuclear Information System (INIS)

Romero-Freire, A.; García Fernández, I.; Simón Torres, M.; Martínez Garzón, F.J.; Martín Peinado, F.J.

2016-01-01

Residual pollution in the Guadiamar Green Corridor still remains after Aználcollar mine spill in 1998. The polluted areas are identified by the absence of vegetation, soil acidic pH and high concentrations of As, Pb, Zn and Cu. Soil toxicity was assessed by lettuce root elongation and induced soil respiration bioassays. In bare soils, total As and Pb concentrations and water-extractable levels for As, Zn and Cu exceeded the toxicity guidelines. Pollutants responsible for toxicity were different depending on the tested organism, with arsenic being most toxic for lettuce and the metal mixture to soil respiration. Soil properties, such as pH or organic carbon content, are key factors to control metal availability and toxicity in the area. According to our results, there is a risk of pollution to living organisms and the soil quality criteria established in the area should be revised to reduce the risk of toxicity. - Highlights: • 15 years after the Aznalcóllar mine spill residual pollution remains in some areas. • Toxic levels were exceeded for total As and Pb and for soluble As, Zn and Cu. • Metals responsible for soil toxicity are different depending on the tested organism. • pH and organic carbon content reduce metal availability and therefore soil toxicity. • Regulatory guidelines in the area should be revised to reduce the risk of toxicity. - Residual pollution in the Guadiamar Green Corridor remains in some areas after long-term stabilization, with some risk of pollution according to toxicity bioassays.

Increased Toxicity of Chemotherapeutic Drugs by All-Trans Retinoic Acid in Cd44 Cells

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A Abbasi

2016-03-01

Full Text Available BACKGROUND AND OBJECTIVE: In recent studies, undifferentiated CD44 cells have been introduced as the major cause of chemotherapeutic drug resistance in esophageal cancer. In this study, we aimed to evaluate the effects of all-trans retinoic acid on reducing chemotherapeutic drug resistance and improving the associated toxic effects. METHODS: In this clinical study, CD44+ and CD44- cells were separated from KYSE-30 cell line, using magnetic-activated cell sorting (MACS method. The cytotoxic effects of retinoic acid treatment, combined with cisplatin and 5-fluorouracil, were separately evaluated in two cell groups, i.e., CD44+ and CD44-. Cytotoxicity was determined by identifying cellular metabolic activity, acridine orange/ethidium bromide staining, and flow cytometry. FINDINGS: In this study, CD44 marker was expressed in 6.25% of the cell population in KYSE-30 cell line. The results of flow cytometry revealed that treatment with a combination of retinoic acid and chemotherapeutic drugs could improve cell cycle arrest in CD44+ cells (p<0.05, unlike CD44- cells. Determination of cellular metabolic activity, increased cell apoptosis along with decreased half maximal inhibitory concentration (IC50, and acridine orange/ethidium bromide staining were indicative of the increased percentage of primary and secondary apoptotic CD44+ cells. However, in CD44- cells, these effects were only observed by using a combination of retinoic acid and cisplatin (p<0.05. CONCLUSION: The present results showed that all-trans retinoic acid could increase the toxicity of cisplatin and 5-fluorouracil in CD44+ cells.

The relationship between metal toxicity and biotic ligand binding affinities in aquatic and soil organisms: a review.

Science.gov (United States)

Ardestani, Masoud M; van Straalen, Nico M; van Gestel, Cornelis A M

2014-12-01

The biotic ligand model (BLM) is a theoretical, potentially mechanistic approach to assess metal bioavailability in soil and aquatic systems. In a BLM, toxicity is linked to the fraction of biotic ligand occupied, which in turn, depends on the various components of the solution, including activity of the metal. Bioavailability is a key factor in determining toxicity and uptake of metals in organisms. In this study, the present status of BLM development for soil and aquatic organisms is summarized. For all species and all metals, toxicity was correlated with the conditional biotic ligand binding constants. For almost all organisms, values for Ag, Cu, and Cd were higher than those for Zn and Ni. The constants derived for aquatic systems seem to be equally valid for soil organisms, but in the case of soils, bioavailability from the soil solution is greatly influenced by the presence of the soil solid phase. Copyright © 2014 Elsevier Ltd. All rights reserved.

Current Status of Air Toxics Management and Its Strategies for Controlling Emissions in Taiwan

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Wen-Tien Tsai

2016-04-01

Full Text Available Since the 1970s, hazardous air pollutants (HAPs, so-called air toxics, have been of great concern because they can cause serious human health effects and have adverse effects on the environment. More noticeably, some of them are known to be human carcinogens. The objective of this paper is to investigate the regulatory systems and human health effects of air toxics which have been designated by the Taiwan government under the Air Pollution Control Act. These toxic air pollutants include acutely toxic gas (i.e., ammonia, chlorine, fluorides, hydrochloric acid, hydrogen cyanide, hydrogen sulfide, nitric acid, phosphoric acid and sulfuric acid, gas containing heavy metals, and carcinogenic chemicals (including formaldehyde, vinyl chloride, asbestos and matter containing asbestos, dioxins and furans, volatile organic compounds, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls. In line with international concern about the carcinogenic risk and environmental persistence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs and heavy metals in recent years, the current status in monitoring and reducing the emissions of PCDDs/PCDFs from stationary sources was analyzed as a case study in the present study. Furthermore, the control strategies for reducing emissions of air toxics from stationary sources in Taiwan were also addressed.

Protective effects of dietary glycine and glutamic acid toward the toxic effects of oxidized mustard oil in rabbits.

Science.gov (United States)

Zeb, Alam; Rahman, Saleem Ur

2017-01-25

The protective role of glycine and glutamic acid against the toxic effects of oxidized oil was studied for the first time. Mustard seed oil was thermally oxidized and characterized for quality characteristics and polyphenolic composition using reversed phase HPLC-DAD. Significant changes in the quality characteristics occurred with thermal oxidation. Fourteen polyphenolic compounds were identified and quantified in oils. Quercetin-3-glucoside, quercetin-3-feruloylsophoroside, catechin, quercetin-3-rutinoside, quercetin-3,7-diglucoside, sinapic acid and vanillic acid hexoside were the major compounds in the fresh and oxidized oil. Oxidized, un-oxidized mustard oils, glycine and glutamic acid were given to rabbits alone or in combination. The biochemical responses were studied in terms of haematological and biochemical parameters and histopathology. It has been observed that biochemical and haematological parameters were adversely affected by the oxidized oil, while supplementation of both amino acids was beneficial in normalizing these parameters. Both amino acids alone have no significant effects, however, oxidized oil affected the liver by enhancing fat accumulation, causing hepatitis, reactive Kupffer cells and necrosis. The co-administration of oxidized oils with glycine or glutamic acid revealed significant recovery of the liver structure and function. In conclusion, glycine or glutamic acid is beneficial and protective against food toxicity and can be considered as an ameliorative food supplement.

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

International Nuclear Information System (INIS)

McKelvie, Jennifer R.; Wolfe, David M.; Celejewski, Magda A.; Alaee, Mehran; Simpson, Andre J.; Simpson, Myrna J.

2011-01-01

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

Acute Toxicity of the Antifouling Compound Butenolide in Non-Target Organisms

KAUST Repository

Zhang, Yi-Fan

2011-08-29

Butenolide [5-octylfuran-2(5H)-one] is a recently discovered and very promising anti-marine-fouling compound. In this study, the acute toxicity of butenolide was assessed in several non-target organisms, including micro algae, crustaceans, and fish. Results were compared with previously reported results on the effective concentrations used on fouling (target) organisms. According to OECD\\'s guideline, the predicted no effect concentration (PNEC) was 0.168 µg l^(−1), which was among one of the highest in representative new biocides. Mechanistically, the phenotype of butenolide-treated Danio rerio (zebrafish) embryos was similar to the phenotype of the pro-caspase-3 over-expression mutant with pericardial edema, small eyes, small brains, and increased numbers of apoptotic cells in the bodies of zebrafish embryos. Butenolide also induced apoptosis in HeLa cells, with the activation of c-Jun N-terminal kinases (JNK), Bcl-2 family proteins, and caspases and proteasomes/lysosomes involved in this process. This is the first detailed toxicity and toxicology study on this antifouling compound.

Arabidopsis and the Genetic Potential for the Phytoremediation of Toxic Elemental and Organic Pollutants

Science.gov (United States)

Cobbett, Christopher S.; Meagher, Richard B.

2002-01-01

In a process called phytoremediation, plants can be used to extract, detoxify, and/or sequester toxic pollutants from soil, water, and air. Phytoremediation may become an essential tool in cleaning the environment and reducing human and animal exposure to potential carcinogens and other toxins. Arabidopsis has provided useful information about the genetic, physiological, and biochemical mechanisms behind phytoremediation, and it is an excellent model genetic organism to test foreign gene expression. This review focuses on Arabidopsis studies concerning: 1) the remediation of elemental pollutants; 2) the remediation of organic pollutants; and 3) the phytoremediation genome. Elemental pollutants include heavy metals and metalloids (e.g., mercury, lead, cadmium, arsenic) that are immutable. The general goal of phytoremediation is to extract, detoxify, and hyperaccumulate elemental pollutants in above-ground plant tissues for later harvest. A few dozen Arabidopsis genes and proteins that play direct roles in the remediation of elemental pollutants are discussed. Organic pollutants include toxic chemicals such as benzene, benzo(a)pyrene, polychlorinated biphenyls, trichloroethylene, trinitrotoluene, and dichlorodiphenyltrichloroethane. Phytoremediation of organic pollutants is focused on their complete mineralization to harmless products, however, less is known about the potential of plants to act on complex organic chemicals. A preliminary survey of the Arabidopsis genome suggests that as many as 700 genes encode proteins that have the capacity to act directly on environmental pollutants or could be modified to do so. The potential of the phytoremediation proteome to be used to reduce human exposure to toxic pollutants appears to be enormous and untapped. PMID:22303204

Enhanced characterization of oil sands acid-extractable organics fractions using electrospray ionization-high-resolution mass spectrometry and synchronous fluorescence spectroscopy.

Science.gov (United States)

Bauer, Anthony E; Frank, Richard A; Headley, John V; Peru, Kerry M; Hewitt, L Mark; Dixon, D George

2015-05-01

The open pit oil sands mining operations north of Fort McMurray, Alberta, Canada, are accumulating tailings waste at a rate approximately equal to 4.9 million m(3) /d. Naphthenic acids are among the most toxic components within tailings to aquatic life, but structural components have largely remained unidentified. In the present study, electrospray ionization high-resolution mass spectrometry (ESI-HRMS) and synchronous fluorescence spectroscopy (SFS) were used to characterize fractions derived from the distillation of an acid-extractable organics (AEO) mixture isolated from oil sands process-affected water (OSPW). Mean molecular weights of each fraction, and their relative proportions to the whole AEO extract, were as follows: fraction 1: 237 Da, 8.3%; fraction 2: 240 Da, 23.8%; fraction 3: 257 Da, 26.7%; fraction 4: 308 Da, 18.9%; fraction 5: 355 Da, 10.0%. With increasing mean molecular weight of the AEO fractions, a concurrent increase occurred in the relative abundance of nitrogen-, sulfur-, and oxygen-containing ions, double-bond equivalents, and degree of aromaticity. Structures present in the higher-molecular-weight fractions (fraction 4 and fraction 5) suggested the presence of heteroatoms, dicarboxyl and dihydroxy groups, and organic acid compounds with the potential to function as estrogens. Because organic acid compositions become dominated by more recalcitrant, higher-molecular-weight acids during natural degradation, these findings are important in the context of oil sands tailings pond water remediation. © 2015 SETAC.

Adolescent Exposure to Toxic Volatile Organic Chemicals From E-Cigarettes.

Science.gov (United States)

Rubinstein, Mark L; Delucchi, Kevin; Benowitz, Neal L; Ramo, Danielle E

2018-04-01

There is an urgent need to understand the safety of e-cigarettes with adolescents. We sought to identify the presence of chemical toxicants associated with e-cigarette use among adolescents. Adolescent e-cigarette users (≥1 use within the past 30 days, ≥10 lifetime e-cigarette use episodes) were divided into e-cigarette-only users (no cigarettes in the past 30 days, urine 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol [NNAL] level 30 pg/mL; n = 16), and never-using controls ( N = 20). Saliva was collected within 24 hours of the last e-cigarette use for analysis of cotinine and urine for analysis of NNAL and levels of 8 volatile organic chemical compounds. Bivariate analyses compared e-cigarette-only users with dual users, and regression analyses compared e-cigarette-only users with dual users and controls on levels of toxicants. The participants were 16.4 years old on average. Urine excretion of metabolites of benzene, ethylene oxide, acrylonitrile, acrolein, and acrylamide was significantly higher in dual users versus e-cigarette-only users (all P < .05). Excretion of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide, and crotonaldehyde were significantly higher in e-cigarette-only users compared with controls (all P < .05). Although e-cigarette vapor may be less hazardous than tobacco smoke, our findings can be used to challenge the idea that e-cigarette vapor is safe, because many of the volatile organic compounds we identified are carcinogenic. Messaging to teenagers should include warnings about the potential risk from toxic exposure to carcinogenic compounds generated by these products. Copyright © 2018 by the American Academy of Pediatrics.

Characteristics of organic acids in the fruit of different pumpkin species.

Science.gov (United States)

Nawirska-Olszańska, Agnieszka; Biesiada, Anita; Sokół-Łętowska, Anna; Kucharska, Alicja Z

2014-04-01

The aim of the research was to determine the composition of organic acids in fruit of different cultivars of three pumpkin species. The amount of acids immediately after fruit harvest and after 3 months of storage was compared. The content of organic acids in the examined pumpkin cultivars was assayed using the method of high performance liquid chromatography (HPLC). Three organic acids (citric acid, malic acid, and fumaric acid) were identified in the cultivars, whose content considerably varied depending on a cultivar. Three-month storage resulted in decreased content of the acids in the case of cultivars belonging to Cucurbita maxima and Cucurbita pepo species, while a slight increase was recorded for Cucurbita moschata species. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

The toxicity of oxidised DWCNTs to the aquatic organisms, and related causing mechanisms

CSIR Research Space (South Africa)

Lukhele, LP

2013-08-01

Full Text Available earlier reported for the three aquatic organisms in earlier scientific reports. Finally, the paper discusses the linkage between the toxicity mechanisms and the physicochemical properties of DWCNTs, namely: agglomeration state, surface chemistry...

PCI-GC-MS-MS approach for identification of non-amino organic acid and amino acid profiles.

Science.gov (United States)

Luan, Hemi; Yang, Lin; Ji, Fenfen; Cai, Zongwei

2017-03-15

Alkyl chloroformate have been wildly used for the fast derivatization of metabolites with amino and/or carboxyl groups, coupling of powerful separation and detection systems, such as GC-MS, which allows the comprehensive analysis of non-amino organic acids and amino acids. The reagents involving n-alkyl chloroformate and n-alcohol are generally employed for providing symmetric labeling terminal alkyl chain with the same length. Here, we developed an asymmetric labeling strategy and positive chemical ionization gas chromatography-tandem mass spectrometry (PCI-GC-MS-MS) approach for determination of non-amino organic acids and amino acids, as well as the short chain fatty acids. Carboxylic and amino groups could be selectively labelled by propyl and ethyl groups, respectively. The specific neutral loss of C 3 H 8 O (60Da), C 3 H 5 O 2 (74Da) and C 4 H 8 O 2 (88Da) were useful in the selective identification for qualitative analysis of organic acids and amino acid derivatives. PCI-GC-MS-MS using multiple reaction monitoring (MRM) was applied for semi-quantification of typical non-amino organic acids and amino acids. This method exhibited a wide range of linear range, good regression coefficient (R 2 ) and repeatability. The relative standard deviation (RSD) of targeted metabolites showed excellent intra- and inter-day precision (chloroformate derivatization. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Organic Acids on Adsorption of Cadmium onto Kaolinite, Goethite, and Bayerite

Institute of Scientific and Technical Information of China (English)

无

2006-01-01

Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals(kaolinite, goethite, and bayerite) were studied under different concentrations and different pH values. Although the types of organic acids and minerals were different, the effects of the organic acids on the adsorption of Cd on the minerals were similar, i.e., the amount of adsorbed Cd with an initial solution pH of 5.0 and initial Cd concentration of 35 mg L-1increased with increasing concentration of the organic acid in solution at lower concentrations, and decreased at higher concentrations. The percentage of Cd adsorbed on the minerals in the presence of the organic acids increased considerably with increasing pH of the solution. Meanwhile, different Cd adsorption in the presence of the organic acids, due to different properties on both organic acids and clay minerals, on kaolinite, goethite, or bayerite for different pHs or organic acid concentrations was found.

Herbal additives and organic acids as antibiotic alternatives in ...

African Journals Online (AJOL)

Herbal additives and organic acids as antibiotic alternatives in broiler chickens diet for organic production. ... Significant increase in lactic acid bacteria counts in ileum and cecum of broiler chicken was shown by all treatments as compared to the control at day 21. In comparison to the control, all treatments significantly ...

The influence of organic acids in relation to acid deposition in controlling the acidity of soil and stream waters on a seasonal basis

International Nuclear Information System (INIS)

Chapman, Pippa J.; Clark, Joanna M.; Reynolds, Brian; Adamson, John K.

2008-01-01

Much uncertainty still exists regarding the relative importance of organic acids in relation to acid deposition in controlling the acidity of soil and surface waters. This paper contributes to this debate by presenting analysis of seasonal variations in atmospheric deposition, soil solution and stream water chemistry for two UK headwater catchments with contrasting soils. Acid neutralising capacity (ANC), dissolved organic carbon (DOC) concentrations and the Na:Cl ratio of soil and stream waters displayed strong seasonal patterns with little seasonal variation observed in soil water pH. These patterns, plus the strong relationships between ANC, Cl and DOC, suggest that cation exchange and seasonal changes in the production of DOC and seasalt deposition are driving a shift in the proportion of acidity attributable to strong acid anions, from atmospheric deposition, during winter to predominantly organic acids in summer. - Seasonal variations in soil solution ANC is controlled by seasonal variations in seasalt deposition and production of dissolved organic acids

Association mapping of main tomato fruit sugars and organic acids

Directory of Open Access Journals (Sweden)

Jiantao Zhao

2016-08-01

Full Text Available Association mapping has been widely used to map the significant associated loci responsible for natural variation in complex traits and are valuable for crop improvement. Sugars and organic acids are the most important metabolites in tomato fruits. We used a collection of 174 tomato accessions composed of S. lycopersicum (123 accessions and S. lycopersicum var cerasiforme (51 accessions to detect significantly associated loci controlling the variation of main sugars and organic acids. The accessions were genotyped with 182 SSRs spreading over the tomato genome. Association mapping was conducted on the main sugars and organic acids detected by gas chromatography-mass spectrometer (GC-MS over two years using the mixed linear model (MLM. We detected a total of 58 significantly associated loci (P<0.001 for the 17 sugars and organic acids, including fructose, glucose, sucrose, citric acid, malic acid. These results not only co-localized with several reported QTLs, including fru9.1/PV, suc9.1/PV, ca2.1/HS, ca3.1/PV, ca4.1/PV and ca8.1/PV, but also provided a list of candidate significantly associated loci to be functionally validated. These significantly associated loci could be used for deciphering the genetic architecture of tomato fruit sugars and organic acids and for tomato quality breeding.

Synergistic Effects of Zinc Oxide Nanoparticles and Fatty Acids on Toxicity to Caco-2 Cells

DEFF Research Database (Denmark)

Cao, Yi; Roursgaard, Martin; Kermanizadeh, Ali

2015-01-01

epithelial (Caco-2) cells. The ZnO NPs exposure concentration dependently induced cytotoxicity to Caco-2 cells showing as reduced proliferation and activity measured by 3 different assays. PA exposure induced cytotoxicity, and coexposure to ZnO NPs and PA showed the largest cytotoxic effects. The presence......Fatty acids exposure may increase sensitivity of intestinal epithelial cells to cytotoxic effects of zinc oxide (ZnO) nanoparticles (NPs). This study evaluated the synergistic effects of ZnO NPs and palmitic acid (PA) or free fatty acids (FFAs) mixture (oleic/PA 2:1) on toxicity to human colon...

Toxicity identification evaluations of produced-water effluents

International Nuclear Information System (INIS)

Sauer, T.C.; Costa, H.J.; Brown, J.S.; Ward, T.J.

1997-01-01

Toxicity identification evaluations (TIEs) were performed on 14 produced-water (PW) samples of various salinities from inland and offshore oil- and gas-production facilities operated by different companies in Wyoming, Texas, California, and Louisiana (USA) to evaluate the efficacy of TIE procedures in determining potential toxicants in PW effluents. The research involved acute (24- and 48-h) freshwater and marine toxicity tests on whole PW and PW fractions generated by standard US Environmental Protection Agency and PW-specific fractionation schemes. Factors influencing PW TIEs were investigated, such as the effect of salinity in selecting fractionation manipulations, the effect of toxicity test replication (i.e., reproducibility) in distinguishing changes in toxicities between whole PW and its fractions, and the suitability of different test species in PW TIEs. The results obtained and lessons learned from conducting these PW TIEs are presented in this article. Components, or fractions, contributing to toxicity differed for each PW with no specific fraction being consistently toxic. For most PW samples, toxicity attributed to any one fraction represented only part of the toxicity of the whole sample. However, no more than two fraction types were identified as potential toxicants in any sample. Potential toxicants identified during this study, besides salinity, included acidic and basic organic compound class fractions, particulates removed by filtration at pH 11, ammonia, hydrocarbons, hydrogen sulfide, material removed by pH change, and volatile compounds

Adsorption of marine phycotoxin okadaic acid on a covalent organic framework.

Science.gov (United States)

Salonen, Laura M; Pinela, Sara R; Fernandes, Soraia P S; Louçano, João; Carbó-Argibay, Enrique; Sarriá, Marisa P; Rodríguez-Abreu, Carlos; Peixoto, João; Espiña, Begoña

2017-11-24

Phycotoxins, compounds produced by some marine microalgal species, can reach high concentrations in the sea when a massive proliferation occurs, the so-called harmful algal bloom. These compounds are especially dangerous to human health when concentrated in the digestive glands of seafood. In order to generate an early warning system to alert for approaching toxic outbreaks, it is very important to improve monitoring methods of phycotoxins in aquatic ecosystems. Solid-phase adsorption toxin tracking devices reported thus far based on polymeric resins have not been able to provide an efficient harmful algal bloom prediction system due to their low adsorption capabilities. In this work, a water-stable covalent organic framework (COF) was evaluated as adsorbent for the hydrophobic toxin okadaic acid, one of the most relevant marine toxins and the parental compound of the most common group of toxins responsible for the diarrhetic shellfish poisoning. Adsorption kinetics of okadaic acid onto the COF in seawater showed that equilibrium concentration was reached in only 60min, with a maximum experimental adsorption of 61mgg -1 . Desorption of okadaic acid from the COF was successful with both 70% ethanol and acetonitrile as solvent, and the COF material could be reused with minor losses in adsorption capacity for three cycles. The results demonstrate that COF materials are promising candidates for solid-phase adsorption in water monitoring devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Boron-containing acids: preliminary evaluation of acute toxicity and access to the brain determined by Raman scattering spectroscopy.

Science.gov (United States)

Soriano-Ursúa, Marvin A; Farfán-García, Eunice D; López-Cabrera, Yessica; Querejeta, Enrique; Trujillo-Ferrara, José G

2014-01-01

Boron-containing compounds (BCCs), particularly boron containing acids (BCAs), have become attractive moieties or molecules in drug development. It has been suggested that when functional groups with boron atoms are added to well-known drugs, the latter are conferred with greater potency and efficacy in relation to their target receptors. However, the use of BCAs in drug development is limited due to the lack of a toxicological profile. Consequently, the aim of the present study was to evaluate the acute toxicity of boric and boronic acids. Thus, a determination was made of the lethal dose (LD50) of test compounds in male CD1 mice, as well as the effective dose required to negatively affect spontaneous motor activity and to produce notable behavioral abnormalities. After treatment of animals at different doses, macroscopic observations were made from a necropsy, and Raman scattering spectroscopic studies were carried out on brain tissue samples. In general, the results show that most of the tested BCAs have very low toxicity, evidenced by the high doses required to induce notable toxic effects (greater than 100 mg/kg of body weight for all compounds, except for 3-thyenilboronic acid). Such toxic effects, presumably mediated by action on the CNS, include eye damage, gastrointestinal effects (e.g., gastric-gut dilatation and fecal retention), sedation, hypnosis and/or trembling. This preliminary toxicological profile suggests that BCAs can be considered potential therapeutic agents or moieties to be added to other compounds in the development of new drugs. Future studies are required to explore possible chronic toxicity of BCCs. Copyright © 2013 Elsevier Inc. All rights reserved.

Crystal and molecular structure of eight organic acid-base adducts from 2-methylquinoline and different acids

Science.gov (United States)

Zhang, Jing; Jin, Shouwen; Tao, Lin; Liu, Bin; Wang, Daqi

2014-08-01

Eight supramolecular complexes with 2-methylquinoline and acidic components as 4-aminobenzoic acid, 2-aminobenzoic acid, salicylic acid, 5-chlorosalicylic acid, 3,5-dinitrosalicylic acid, malic acid, sebacic acid, and 1,5-naphthalenedisulfonic acid were synthesized and characterized by X-ray crystallography, IR, mp, and elemental analysis. All of the complexes are organic salts except compound 2. All supramolecular architectures of 1-8 involve extensive classical hydrogen bonds as well as other noncovalent interactions. The results presented herein indicate that the strength and directionality of the classical hydrogen bonds (ionic or neutral) between acidic components and 2-methylquinoline are sufficient to bring about the formation of binary organic acid-base adducts. The role of weak and strong noncovalent interactions in the crystal packing is ascertained. These weak interactions combined, the complexes 1-8 displayed 2D-3D framework structure.

Behavioral, clinical, and pathological characterization of acid metalliferous water toxicity in mallards

Science.gov (United States)

Isanhart, John P.; Wu, Hongmei; Pandher, Karamjeet; MacRae, Russell K.; Cox, Stephen B.; Hooper, Michael J.

2011-01-01

From September to November 2000, United States Fish and Wildlife Service biologists investigated incidents involving 221 bird deaths at 3 mine sites located in New Mexico and Arizona. These bird deaths primarily involved passerine and waterfowl species and were assumed to be linked to consumption of acid metalliferous water (AMW). Because all of the carcasses were found in or near pregnant leach solution ponds, tailings ponds, and associated lakes or storm water retention basins, an acute-toxicity study was undertaken using a synthetic AMW (SAMW) formulation based on the contaminant profile of a representative pond believed to be responsible for avian mortalities. An acute oral-toxicity trial was performed with a mixed-sex group of mallards (Anas platyrhynchos). After a 24-h pretreatment food and water fast, gorge drinking was evident in both SAMW treatment and control groups, with water consumption rates greatest during the initial drinking periods. Seven of nine treated mallards were killed in extremis within 12 h after the initiation of dose. Total lethal doses of SAMW ranged from 69.8 to 270.1 mL/kg (mean ± SE 127.9 ± 27.1). Lethal doses of SAMW were consumed in as few as 20 to 40 min after first exposure. Clinical signs of SAMW toxicity included increased serum uric acid, aspartate aminotransferase, creatine kinase, potassium, and P levels. PCV values of SAMW-treated birds were also increased compared with control mallards. Histopathological lesions were observed in the esophagus, proventriculus, ventriculus, and duodenum of SAMW-treated mallards, with the most distinctive being erosion and ulceration of the kaolin of the ventriculus, ventricular hemorrhage and/or congestion, and duodenal hemorrhage. Clinical, pathological, and tissue-residue results from this study are consistent with literature documenting acute metal toxicosis, especially copper (Cu), in avian species and provide useful diagnostic profiles for AMW toxicity or mortality events. Blood and

Microbial transformations of natural organic compounds and radionuclides in subsurface environments

International Nuclear Information System (INIS)

Francis, A.J.

1985-10-01

A major national concern in the subsurface disposal of energy wastes is the contamination of ground and surface waters by waste leachates containing radionuclides, toxic metals, and organic compounds. Microorganisms play an important role in the transformation of organic compounds, radionuclides, and toxic metals present in the waste and affect their mobility in subsurface environments. Microbial processes involved in dissolution, mobilization, and immobilization of toxic metals under aerobic and anaerobic conditions are briefly reviewed. Metal complexing agents and several organic acids produced by microbial action affect mobilization of radionuclides and toxic metals in subsurface environments. Information on the persistence of and biodegradation rates of synthetic as well as microbiologically produced complexing agents is scarce but important in determining the mobility of metal organic complexes in subsoils. Several gaps in knowledge in the area of microbial transformation of naturally occurring organics, radionuclides, and toxic metals have been identified, and further basic research has been suggested. 31 refs., 1 fig., 3 tabs

Metabolic evolution of Escherichia coli strains that produce organic acids

Science.gov (United States)

Grabar, Tammy; Gong, Wei; Yocum, R Rogers

2014-10-28

This invention relates to the metabolic evolution of a microbial organism previously optimized for producing an organic acid in commercially significant quantities under fermentative conditions using a hexose sugar as sole source of carbon in a minimal mineral medium. As a result of this metabolic evolution, the microbial organism acquires the ability to use pentose sugars derived from cellulosic materials for its growth while retaining the original growth kinetics, the rate of organic acid production and the ability to use hexose sugars as a source of carbon. This invention also discloses the genetic change in the microorganism that confers the ability to use both the hexose and pentose sugars simultaneously in the production of commercially significant quantities of organic acids.

Top value platform chemicals: bio-based production of organic acids.

Science.gov (United States)

Becker, Judith; Lange, Anna; Fabarius, Jonathan; Wittmann, Christoph

2015-12-01

Driven by the quest for sustainability, recent years have seen a tremendous progress in bio-based production routes from renewable raw materials to commercial goods. Particularly, the production of organic acids has crystallized as a competitive and fast-evolving field, related to the broad applicability of organic acids for direct use, as polymer building blocks, and as commodity chemicals. Here, we review recent advances in metabolic engineering and industrial market scenarios with focus on organic acids as top value products from biomass, accessible through fermentation and biotransformation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modulation of hexavalent chromium toxicity on Οriganum vulgare in an acidic soil amended with peat, lime, and zeolite.

Science.gov (United States)

Antoniadis, Vasileios; Zanni, Anna A; Levizou, Efi; Shaheen, Sabry M; Dimirkou, Anthoula; Bolan, Nanthi; Rinklebe, Jörg

2018-03-01

Dynamics of chromate (Cr(VI)) in contaminated soils may be modulated by decreasing its phytoavailability via the addition of organic matter-rich amendments, which might accelerate Cr(VI) reduction to inert chromite (Cr(III)) or high-cation exchange capacity amendments. We studied Cr(VI) phytoavailability of oregano in a Cr(VI)-spiked acidic soil non-treated (S) and treated with peat (SP), lime (SL), and zeolite (SZ). The addition of Cr(VI) increased the concentrations of Cr(VI) and Cr(III) in soils and plants, especially in the lime-amended soil. The plant biomass decreased in the lime-amended soil compared to the un-spiked soil (control) due to decreased plant phosphorus concentrations and high Cr(VI) concentrations in root at that treatment. Oregano in the peat-amended soil exhibited significantly less toxic effects, due to the role of organic matter in reducing toxic Cr(VI) to Cr(III) and boosted plant vigour in this treatment. In the lime-amended soil, the parameters of soil Cr(VI), soil Cr(III), and root Cr(III) increased significantly compared to the non-amended soil, indicating that Cr(VI) reduction to Cr(III) was accelerated at high pH. Added zeolite failed to decreased Cr(VI) level to soil and plant. Oregano achieved a total uptake of Cr(III) and Cr(VI) of 0.275 mg in plant kg -1 soil in a pot in the non-amended soil. We conclude that peat as soil amendment might be considered as a suitable option for decreasing Cr(VI) toxicity in soil and plant, and that oregano as tolerant plant species has a certain potential to be used as a Cr accumulator. Copyright © 2017 Elsevier Ltd. All rights reserved.

A 90-day repeated-dose toxicity study of dietary alpha linolenic acid-enriched diacylglycerol oil in rats.

Science.gov (United States)

Bushita, Hiroto; Ito, Yuichi; Saito, Tetsuji; Nukada, Yuko; Ikeda, Naohiro; Nakagiri, Hideaki; Saito, Kazutoshi; Morita, Osamu

2018-05-31

Diets supplemented with alpha-linolenic acid (ALA)-enriched diacylglycerol (DAG) oil-which mainly consists of oleic and linolenic, linoleic acids-have potential health benefits in terms of preventing or managing obesity. Although safety of DAG oil has been extensively investigated, toxicity of ALA-DAG oil has not been well understood. Hence, the present study was conducted to clarify the potential adverse effects, if any, of ALA-DAG oil in rats (10/sex/group) fed diets containing 1.375%, 2.75%, or 5.5% ALA-DAG oil for 90 days. Compared to control rats fed rapeseed oil or ALA-triacylglycerol oil (flaxseed oil), rats receiving ALA-DAG oil did not reveal any toxicologically significant treatment-related changes as evaluated by clinical signs, functional observational battery, body weight, food consumption, ophthalmology, urinalysis, hematology, clinical chemistry, organ weight, necropsy and histopathology. The no observed adverse effect levels for dietary exposure to ALA-DAG oil for male and female rats were 2916 and 3326 mg/kg body weight/day, respectively, the highest dose tested. The findings from this study suggest that consumption of ALA-DAG oil is unlikely to cause adverse effects. Copyright © 2018. Published by Elsevier Inc.

Evaluation of acute toxicity of genabilic acid (menbutone 10% in rabbits

Directory of Open Access Journals (Sweden)

S. O. El Okle

2014-09-01

Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 A complete investigation of the acute toxicity of a choleretic compound, menbutone, was performed in rabbits, including lethal dose for 50% of rabbits determination, clinical signs observation and in vivo and post-mortem examinations. Haematological, biochemical and histopathological changes resulting from intramuscular injection of menbutone were also investigated at dose 400 mg/kg body weight. Acute toxicity of menbutone at dose of 400 mg/kg BW induced interstitial myocarditis and multifocal necrosis, whereas serum creatine phosphokinase, creatinine phosphokinase-MB isoenzyme and aspartate aminotransferase activities were significantly increased. Elevation of serum alanine aminotransferase and alkaline phosphatase activities and total bilirubin level associated with lowered albumin content was consistent with histopathological changes of hepatic tissues; hepatic necrosis and fatty infiltration were pronounced indicators of injuries. Renal tubular necrosis and interstitial nephritis were also observed in intoxicated rabbits. Menbutone also induced variations in some haematological parameters. We concluded that acute toxicity of menbutone in rabbits occurred at accidental high doses, as the lethal dose was about 50 fold over the recommended therapeutic dose for other animals. Cardiac muscle, liver and kidneys are the main target organs for menbutone toxicity. Menbutone is not recommended for use in rabbits suffering from any cardiacand hepatic disorders, especially in overdosing situations.

Potentially toxic metals in ombrotrophic peat along a 400 km English-Scottish transect

Energy Technology Data Exchange (ETDEWEB)

Smith, E.J. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); Hughes, S. [Centre for Ecology and Hydrology (Bangor), Deiniol Road, Bangor, Gwynedd LL57 2UP (United Kingdom); Lawlor, A.J. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); Lofts, S. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); Simon, B.M. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); Stevens, P.A. [Centre for Ecology and Hydrology (Bangor), Deiniol Road, Bangor, Gwynedd LL57 2UP (United Kingdom); Stidson, R.T. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); Tipping, E. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom)]. E-mail: et@ceh.ac.uk; Vincent, C.D. [Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom)

2005-07-15

Four samples of ombrotrophic peat were collected from each of 10 upland locations in a transect from the southern Pennines to the Highland Boundary Fault, a total distance of ca. 400 km. Bulk compositions and other properties were determined. Total contents of Al and heavy metals (Ni, Cu, Zn, Cd, Pb) were determined following digestion with hydrofluoric acid, and concentrations of metals extractable with dilute nitric acid were also measured. Supernatants obtained from aqueous extractions of the peat samples were analysed for pH, major cations and anions, dissolved organic carbon and dissolved metals, and concentrations of free metal ions (Al{sup 3+}, Ni{sup 2+}, etc.) were estimated by applying a chemical speciation model. Both total and HNO{sub 3}-extractable metal concentrations varied along the transect, the highest values being found at locations close to industrial and former mining areas. The HNO{sub 3}-extractable soil metal contents of Ni, Cu and Cd were appreciably lower than lowest-observed-effect-concentrations (LOEC) for toxicity towards microorganisms in acid, organic rich soils. However, the contents of Zn at two locations, and of Pb at five locations exceeded LOECs, suggesting that they may be exerting toxic effects in the peats. Soil solution concentrations of free heavy metal ions (Cu{sup 2+}, Zn{sup 2+}, Cd{sup 2+}, Pb{sup 2+}) were substantially lower than LOECs for toxicity towards vascular plants, whereas concentrations of Al{sup 3+} were near to toxic levels at two locations. - P eat metal contents depend upon proximity to industrial and mining areas; the metals may be exerting toxic effects in some places.

Corrosion of alloy C-22 in organic acid solutions

International Nuclear Information System (INIS)

Carranza, Ricardo M.; Rodriguez, Martin A.; Giordano, Celia M.

2007-01-01

Electrochemical studies such as cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS) were performed to determine the corrosion behavior of Alloy 22 (N06022) in 1M NaCl solutions at various pH values from acidic to neutral at 90 C degrees. All the tested material was wrought Mill Annealed (MA). Tests were also performed in NaCl solutions containing weak organic acids such as oxalic, acetic, citric and picric acids. Results show that the corrosion rate of Alloy 22 was significantly higher in solutions containing oxalic acid than in solutions of pure NaCl at the same pH. Citric and Picric acids showed a slightly higher corrosion rate, and Acetic acid maintained the corrosion rate of pure chloride solutions at the same pH. Organic acids revealed to be weak inhibitors for crevice corrosion. Higher concentration ratios, compared to nitrate ions, were needed to completely inhibit crevice corrosion in chloride solutions. Results are discussed considering acid dissociation constants, buffer capacity and complex formation constants of the different weak acids. (author) [es

In Vitro and In Vivo Toxicity of Garcinia or Hydroxycitric Acid: A Review

Directory of Open Access Journals (Sweden)

Li Oon Chuah

2012-01-01

Full Text Available Obesity is one of the pandemic chronic diseases commonly associated with health disorders such as heart attack, high blood pressure, diabetes or even cancer. Among the current natural products for obesity and weight control, Garcinia or more specifically hydroxycitric acid (HCA extracted from Garcinia has been widely used. The evaluation of the potential toxicity of weight control supplement is of the utmost importance as it requires long term continuous consumption in order to maintain its effects. Majority of reports demonstrated the efficacy of Garcinia/HCA without any toxicity found. However, a few clinical toxicity reports on weight-loss diet supplements of which some were combinations that included Garcinia/HCA as an active ingredient showed potential toxicity towards spermatogenesis. Nonetheless, it cannot be concluded that Garcinia/HCA is unsafe. Those products which have been reported to possess adverse effects are either polyherbal or multi-component in nature. To date, there is no case study or report showing the direct adverse effect of HCA. The structure, mechanism of action, long history of the use of Garcinia/HCA and comprehensive scientific evidence had shown “no observed adverse effect level (NOAEL” at levels up to 2800 mg/day, suggesting its safety for use.

Toxic pollutants emitted from thermal decomposition of phthalimide compounds

Energy Technology Data Exchange (ETDEWEB)

Chen Kai; Mackie, John C.; Wojtalewicz, Dominika; Kennedy, Eric M. [Process Safety and Environmental Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308 (Australia); Dlugogorski, Bogdan Z., E-mail: Bogdan.Dlugogorski@newcastle.edu.au [Process Safety and Environmental Protection Research Group, School of Engineering, University of Newcastle, Callaghan, New South Wales 2308 (Australia)

2011-03-15

Phthalimide (PI) and tetrahydrophthalimide (THPI) are two structurally similar compounds extensively used as intermediates for the synthesis of variety of industrial chemicals. This paper investigates the thermal decomposition of PI and THPI under oxygen rich to oxygen lean conditions, quantifying the production of toxicants and explaining their formation pathways. The experiments involved a plug flow reactor followed by silica cartridges, activated charcoal trap and a condenser, with the decomposition products identified and quantified by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and micro gas chromatography ({mu}GC). The density functional theory (DFT) calculations served to obtain dissociation energies and reaction pathways, to elucidate the reaction mechanism. The oxidation of PI and THPI produced several toxic nitrogen-containing gases and volatile organic compounds, including hydrogen cyanide, isocyanic acid, nitrogen oxides, benzonitrile, maleimide and tentatively identified benzenemethanimine. The detection of dibenzo-p-dioxin (DD) and dibenzofuran (DF) suggests potential formation of the toxic persistent organic pollutants (POPs) in fires involving PI and THPI, in presence of a chlorine source. The oxidation of THPI produced 2-cyclohexen-1-one, a toxic unsaturated ketone. The results of the present study provide the data for quantitative risk assessments of emissions of toxicants in combustion processes involving PI and THPI.

Toxic pollutants emitted from thermal decomposition of phthalimide compounds

International Nuclear Information System (INIS)

Chen Kai; Mackie, John C.; Wojtalewicz, Dominika; Kennedy, Eric M.; Dlugogorski, Bogdan Z.

2011-01-01

Phthalimide (PI) and tetrahydrophthalimide (THPI) are two structurally similar compounds extensively used as intermediates for the synthesis of variety of industrial chemicals. This paper investigates the thermal decomposition of PI and THPI under oxygen rich to oxygen lean conditions, quantifying the production of toxicants and explaining their formation pathways. The experiments involved a plug flow reactor followed by silica cartridges, activated charcoal trap and a condenser, with the decomposition products identified and quantified by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and micro gas chromatography (μGC). The density functional theory (DFT) calculations served to obtain dissociation energies and reaction pathways, to elucidate the reaction mechanism. The oxidation of PI and THPI produced several toxic nitrogen-containing gases and volatile organic compounds, including hydrogen cyanide, isocyanic acid, nitrogen oxides, benzonitrile, maleimide and tentatively identified benzenemethanimine. The detection of dibenzo-p-dioxin (DD) and dibenzofuran (DF) suggests potential formation of the toxic persistent organic pollutants (POPs) in fires involving PI and THPI, in presence of a chlorine source. The oxidation of THPI produced 2-cyclohexen-1-one, a toxic unsaturated ketone. The results of the present study provide the data for quantitative risk assessments of emissions of toxicants in combustion processes involving PI and THPI.

Toxicity evaluation of chlorinated organic compounds using immortalized rat hepatocytes; Fushika rat kansaibo wo mochiita yuki enso kagobutsu no dokusei hyoka no kokoromi

Energy Technology Data Exchange (ETDEWEB)

Sone, H; Nakajima, M; Yonemoto, J [National Institute for Environmental Studies, Tsukuba (Japan)

1997-11-10

Chlorinated organic compounds has high priority for toxicity screening among environmental hazardous chemicals. In the present study, we used immortalized rat hepatocytes as a liver model in vitro to evaluate the toxicity of nine chlorinated organic compounds. Toxicity of nine chlorinated organic compounds were evaluated to cellular viability of immortalized rat hapatocytes. The potency of the toxicity based on 50% inhibitory concentration (IC50) value was in the following order: triclocalban>triclosan>3,4-dichloroaniline>2,5-diclorophenol> 2,5-dichloroanisole>p-dichlorobenzene> p-chloroaniline>o-dichlorobenzene=tris (2-chloroethyl) phosphate. The rank order of cytotoxic potency of nine chemicals was compared with toxicity information using animals. The rank order of cytotoxic potency did not relative to the order referenced mean lethal dose (LD50) as an index of acute toxicity of rats or mice. However, the rank order of cytotoxic potency relatively correlated non-observed adverse effect level (NOAEL) under the exposure duration adjusted for chronic toxicity in vivo. These data suggests that the origin of testing cell had better to make match target organ of toxic chemicals for extrapolation from data of bioassay in vitro to in vivo. 16 refs., 2 figs., 3 tabs.

Cyclosporine A and palmitic acid treatment synergistically induce cytotoxicity in HepG2 cells

Energy Technology Data Exchange (ETDEWEB)

Luo, Yi, E-mail: yi.luo@pfizer.com; Rana, Payal; Will, Yvonne

2012-06-01

Immunosuppressant cyclosporine A (CsA) treatment can cause severe side effects. Patients taking immunosuppressant after organ transplantation often display hyperlipidemia and obesity. Elevated levels of free fatty acids have been linked to the etiology of metabolic syndromes, nonalcoholic fatty liver and steatohepatitis. The contribution of free fatty acids to CsA-induced toxicity is not known. In this study we explored the effect of palmitic acid on CsA-induced toxicity in HepG2 cells. CsA by itself at therapeutic exposure levels did not induce detectible cytotoxicity in HepG2 cells. Co-treatment of palmitic acid and CsA resulted in a dose dependent increase in cytotoxicity, suggesting that fatty acid could sensitize cells to CsA-induced cytotoxicity at the therapeutic doses of CsA. A synergized induction of caspase-3/7 activity was also observed, indicating that apoptosis may contribute to the cytotoxicity. We demonstrated that CsA reduced cellular oxygen consumption which was further exacerbated by palmitic acid, implicating that impaired mitochondrial respiration might be an underlying mechanism for the enhanced toxicity. Inhibition of c-Jun N-terminal kinase (JNK) attenuated palmitic acid and CsA induced toxicity, suggesting that JNK activation plays an important role in mediating the enhanced palmitic acid/CsA-induced toxicity. Our data suggest that elevated FFA levels, especially saturated FFA such as palmitic acid, may be predisposing factors for CsA toxicity, and patients with underlying diseases that would elevate free fatty acids may be susceptible to CsA-induced toxicity. Furthermore, hyperlipidemia/obesity resulting from immunosuppressive therapy may aggravate CsA-induced toxicity and worsen the outcome in transplant patients. -- Highlights: ► Palmitic acid and cyclosporine (CsA) synergistically increased cytotoxicity. ► The impairment of mitochondrial functions may contribute to the enhanced toxicity. ► Inhibition of JNK activity attenuated

Ice nucleation in sulfuric acid/organic aerosols: implications for cirrus cloud formation

Directory of Open Access Journals (Sweden)

M. R. Beaver

2006-01-01

Full Text Available Using an aerosol flow tube apparatus, we have studied the effects of aliphatic aldehydes (C3 to C10 and ketones (C3 and C9 on ice nucleation in sulfuric acid aerosols. Mixed aerosols were prepared by combining an organic vapor flow with a flow of sulfuric acid aerosols over a small mixing time (~60 s at room temperature. No acid-catalyzed reactions were observed under these conditions, and physical uptake was responsible for the organic content of the sulfuric acid aerosols. In these experiments, aerosol organic content, determined by a Mie scattering analysis, was found to vary with the partial pressure of organic, the flow tube temperature, and the identity of the organic compound. The physical properties of the organic compounds (primarily the solubility and melting point were found to play a dominant role in determining the inferred mode of nucleation (homogenous or heterogeneous and the specific freezing temperatures observed. Overall, very soluble, low-melting organics, such as acetone and propanal, caused a decrease in aerosol ice nucleation temperatures when compared with aqueous sulfuric acid aerosol. In contrast, sulfuric acid particles exposed to organic compounds of eight carbons and greater, of much lower solubility and higher melting temperatures, nucleate ice at temperatures above aqueous sulfuric acid aerosols. Organic compounds of intermediate carbon chain length, C4-C7, (of intermediate solubility and melting temperatures nucleated ice at the same temperature as aqueous sulfuric acid aerosols. Interpretations and implications of these results for cirrus cloud formation are discussed.

Organic acid profile of commercial sour cassava starch

Directory of Open Access Journals (Sweden)

DEMIATE I.M.

1999-01-01

Full Text Available Organic acids are present in sour cassava starch ("polvilho azedo" and contribute with organoleptic and physical characteristics like aroma, flavor and the exclusive baking property, that differentiate this product from the native cassava starch. Samples of commercial sour cassava starch collected in South and Southeast Brazil were prepared for high performance liquid chromatography (HPLC analysis. The HPLC equipment had a Biorad Aminex HPX-87H column for organic acid analysis and a refractometric detector. Analysis was carried out with 0.005M sulfuric acid as mobile phase, 0.6ml/min flow rate and column temperature of 60° C. The acids quantified were lactic (0.036 to 0.813 g/100g, acetic (0 to 0.068 g/100g, propionic (0 to 0.013 g/100g and butyric (0 to 0.057 g/100g, that are produced during the natural fermentation of cassava starch. Results showed large variation among samples, even within the same region. Some samples exhibited high acid levels, mainly lactic acid, but in these neither propionic nor butyric acids were detected. Absence of butyric acid was not expected because this is an important component of the sour cassava starch aroma, and the lack of this acid may suggest that such samples were produced without the natural fermentation step.

Formation of organic acids from trace carbon in acidic oxidizing media

International Nuclear Information System (INIS)

Terrassier, C.

2003-01-01

Carbon 14 does not fully desorb as CO 2 during the hot concentrated nitric acid dissolution step of spent nuclear fuel reprocessing: a fraction is entrained in solution into the subsequent process steps as organic species. The work described in this dissertation was undertaken to identify the compounds arising from the dissolution in 3 N nitric acid of uranium carbides (selected as models of the chemical form of carbon 14 in spent fuel) and to understand their formation and dissolution mechanism. The compounds were present at traces in solution, and liquid-solid extraction on a specific stationary phase (porous graphite carbon) was selected to concentrate the monoaromatic poly-carboxylic acids including mellitic acid, which is mentioned in the literature but has not been formally identified. The retention of these species and of oxalic acid - also cited in the literature - was studied on this stationary phase as a function of the mobile phase pH, revealing an ion exchange retention mechanism similar to the one observed for benzyltrimethylammonium polystyrene resins. The desorption step was then optimized by varying the eluent pH and ionic strength. Mass spectrometry analysis of the extracts identified acetic acid, confirmed the presence of mellitic acid, and revealed compounds of high molecular weight (about 200 g/mol); the presence of oxalic acid was confirmed by combining gas chromatography and mass spectrometry. Investigating the dissolution of uranium and zirconium carbides in nitric acid provided considerable data on the reaction and suggested a reaction mechanism. The reaction is self-catalyzing via nitrous acid, and the reaction rate de pends on the acidity and nitrate ion concentration in solution. Two uranium carbide dissolution mechanisms are proposed: one involves uranium at oxidation state +IV in solution, coloring the dissolution solution dark green, and the other assumes that uranium monocarbide is converted to uranium oxide. The carboxylic acid

Characterization of acid tars

Energy Technology Data Exchange (ETDEWEB)

Leonard, Sunday A., E-mail: sunday.leonard@ucl.ac.uk [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Stegemann, Julia A. [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Roy, Amitava [J. Bennett Johnston, Sr., Centre for Advance Microstructures and Devices (CAMD), 6980 Jefferson Highway, Louisiana State University, Baton Rouge, LA, 70806 (United States)

2010-03-15

Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

Characterization of acid tars

International Nuclear Information System (INIS)

Leonard, Sunday A.; Stegemann, Julia A.; Roy, Amitava

2010-01-01

Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

Alternatives to Organic Solvents in Industrial Cleaning Processes

DEFF Research Database (Denmark)

Jacobsen, Thomas

1998-01-01

To control chemical hazards in work places, substitution of harmful substances with less harmful or non-toxic products is now a method used in many countries and in many companies. It has previously been demonstrated that it is desirable and possible to use non-volatile, low-toxic vegetable...... cleaning agents in offset printing companies instead of volatile, toxic organic solvents. The present study is based on a project with the aim of defining other industrial processes, where organic solvents used for cleaning or degreasing can be replaced by non-volatile, low-toxic products, which are based...... on esters from fatty acids of vegetable origin (vegetable esters - VE).The study indicates that industrial cleaning/degreasing with organic solvents may be substituted with VEs on metal surfaces and on some coated surfaces, in manufacture of paints and inks, use of paints, use of inks (printing), metal...

Astaxanthin and Docosahexaenoic Acid Reverse the Toxicity of the Maxi-K (BK Channel Antagonist Mycotoxin Penitrem A

Directory of Open Access Journals (Sweden)

Amira A. Goda

2016-11-01

Full Text Available Penitrem A (PA is a food mycotoxin produced by several terrestrial and few marine Penicillium species. PA is a potent tremorgen through selective antagonism of the calcium-dependent potassium BK (Maxi-K channels. Discovery of natural products that can prevent the toxic effects of PA is important for food safety. Astaxanthin (AST is a marine natural xanthophyll carotenoid with documented antioxidant activity. Unlike other common antioxidants, AST can cross blood brain barriers (BBBs, inducing neuroprotective effects. Docosahexaenoic acid (DHA is polyunsaturated ω-3 fatty acid naturally occurring in fish and algae. DHA is essential for normal neurological and cellular development. This study evaluated the protective activity of AST and DHA against PA-induced toxicity, in vitro on Schwann cells CRL-2765 and in vivo in the worm Caenorhbitidis elegans and Sprague Dawley rat models. PA inhibited the viability of Schwann cells, with an IC50 of 22.6 μM. Dose-dependent treatments with 10–100 μM DHA significantly reversed the PA toxicity at its IC50 dose, and improved the survival of Schwann cells to 70.5%–98.8%. Similarly, dose-dependent treatments with 10–20 μM AST reversed the PA toxicity at its IC50 dose and raised these cells’ survival to 61.7%–70.5%. BK channel inhibition in the nematode C. elegans is associated with abnormal reversal locomotion. DHA and AST counteracted the in vivo PA BK channel antagonistic activity in the C. elegans model. Rats fed a PA-contaminated diet showed high levels of glutamate (GLU, aspartate (ASP, and gamma amino butyric acid (GABA, with observed necrosis or absence of Purkinjie neurons, typical of PA-induced neurotoxicity. Dopamine (DA, serotonin (5-HT, and norepinephrine (NE levels were abnormal, Nitric Oxide (NO and Malondialdehyde (MDA levels were significantly increased, and total antioxidant capacity (TAC level in serum and brain homogenates was significantly decreased in PA-treated rats. DHA and AST

Effects of toxic cyanobacteria and ammonia on flesh quality of blunt snout bream (Megalobrama amblycephala).

Science.gov (United States)

Wang, Li; Chen, Chuanyue; Liu, Wanjing; Xia, Hu; Li, Jian; Zhang, Xuezhen

2017-03-01

Toxic cyanobacterial blooms result in the production of an organic biomass containing cyanotoxins (e.g. microcystins) and an elevated ammonia concentration in the water environment. The ingestion of toxic cyanobacteria and exposure to ammonia are grave hazards for fish. The present study assessed the effects of dietary toxic cyanobacteria and ammonia exposure on the flesh quality of blunt snout bream (Megalobrama amblycephala). Dietary toxic cyanobacteria and ammonia exposure had no impact on fish growth performance, fillet proximate composition and drip loss, whereas it significantly decreased fillet total amino acids, total essential amino acids, hardness and gumminess, and increased fillet ultimate pH as well as malondialdehyde content. However, there was no significant interaction between dietary toxic cyanobacteria and ammonia exposure on these parameters. Additionally, dietary toxic cyanobacteria significantly increased fillet initial pH, thaw loss and protein carbonyl content, whereas ammonia exposure did not. The results of the present study indicate that dietary toxic cyanobacteria and ammonia exposure reduced the quality of blunt snout bream fillet. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Protective efficacy of folic acid and vitamin B12 against nicotine-induced toxicity in pancreatic islets of the rat

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Bhattacharjee Ankita

2015-06-01

Full Text Available Although cigarette smoking is associated with insulin resistance and an increased risk for type 2 diabetes, few studies have examined the effect of nicotine on the adult endocrine pancreas. In this study, male Wister rats were treated with nicotine (3 mg/kg body weight/day with or without supplementation of folic acid (36 μg/kg body weight/day or vitamin B12 (0.63 μg/kg body weight/day alone or in combination. Fasting blood glucose, insulin and HBA1C level and different oxidative and anti-oxidative stress parameters were measured and pancreatic tissue sections were stained with eosin-haematoxylene. Data were analysed by nonparametric statistics. The results revealed that nicotine induced prediabetes condition with subsequent damage to pancreatic islets in rats. Nicotine also caused oxidative stress in pancreatic tissue as evidenced by increased nitric oxide and malondialdehyde level and decreased superoxide dismutase, catalase and reduced glutathione level. Compared to vitamin B12 supplementation, folic acid blunted the nicotine-induced toxicity in pancreatic islets with higher efficacy. Further, folic acid and vitamin B12 in combination were able to confer significant protection on pancreatic islets against nicotine induced toxicity. These results suggest that supplementation of folic acid and vitamin B12 in combination may be a possible strategy of detoxification against nicotine-induced toxicity in pancreatic islets of the rat.

Acute and chronic toxicity of boron to a variety of freshwater organisms.

Science.gov (United States)

Soucek, David J; Dickinson, Amy; Koch, Brian T

2011-08-01

Boron enters the aquatic environment from various sources, including weathering of borates, sewage effluents, coal combustion, use of cleaning compounds, and agrochemicals. The present study was designed to generate data on acute and chronic boron toxicity in support of an update of water quality standards in Illinois, USA. We examined the acute toxicity of boron to eight different freshwater organisms including a fish, an insect, two crustaceans, and four bivalve mollusks. To our knowledge, this is the first study to present data on the toxicity of boron to freshwater mollusks. We also sought to clarify whether hardness or pH affect boron toxicity to aquatic life, and to quantify chronic effect levels in two freshwater species. Sensitivity among the various species ranged widely, with the fathead minnow (Pimephales promelas) being the most sensitive. Neither pH nor hardness had a consistent effect on acute boron toxicity to two crustaceans (Ceriodaphnia dubia and Hyalella azteca), but we observed evidence that chloride reduces boron toxicity to H. azteca. The fathead minnow, while more acutely sensitive than the other species, had a lower acute to chronic ratio than did H. azteca, which had reduced reproduction at 13 mg/L. While we do not know the extent to which the eight tested species represent the range of sensitivities of native but untested species in Illinois, the current water quality standard for Illinois (1 mg/L) is conservative with regard to the native species tested thus far. Copyright © 2011 SETAC.

Photodegradation kinetics, transformation, and toxicity prediction of ketoprofen, carprofen, and diclofenac acid in aqueous solutions.

Science.gov (United States)

Li, Jian; Ma, Li-Yun; Li, Lu-Shuang; Xu, Li

2017-12-01

Photodegradation of 3 commonly used nonsteroidal anti-inflammatory drugs, ketoprofen, carprofen, and diclofenac acid, was conducted under ultraviolet (UV) irradiation. The kinetic results showed that the 3 pharmaceuticals obeyed the first-order reaction with decreasing rate constants of 1.54 × 10 -4 , 5.91 × 10 -5 , and 7.78 × 10 -6  s -1 for carprofen, ketoprofen, and diclofenac acid, respectively. Moreover, the main transformation products were identified by ion-pair liquid-liquid extraction combined with injection port derivatization-gas chromatography-mass spectrometry and high-performance liquid chromatography-quadrupole-time of flight mass spectrometric analysis. There were 8, 3, and 6 transformation products identified for ketoprofen, carprofen, and diclofenac acid, respectively. Decarboxylation, dechlorination, oxidation, demethylation, esterification, and cyclization were proposed to be associated with the transformation of the 3 pharmaceuticals. Toxicity prediction of the transformation products was conducted on the EPI Suite software based on ECOSAR model, and the results indicate that some of the transformation products were more toxic than the parent compounds. The present study provides the foundation to understand the transformation behavior of the studied pharmaceuticals under UV irradiation. Environ Toxicol Chem 2017;36:3232-3239. © 2017 SETAC. © 2017 SETAC.

Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

International Nuclear Information System (INIS)

Chattopadhyay, P; Pandey, A; Goyary, D; Chaurasia, A; Singh, L; Veer, V.

2012-01-01

The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m ( 99m Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99m Tc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

Investigating salt and naphthenic acids interactions in the toxicity of oil sands process water to freshwater invertebrates

International Nuclear Information System (INIS)

Turcotte, D.; Kautzman, M.; Wojnarowicz, P.; Cutter, J.; Bird, E.; Liber, K.

2010-01-01

The hot water extraction process used to produce bitumens from oil sands produces a large volume of oil sands process water (OSPW) that contain elevated concentrations of naphthenic acids (NA) and salts. Many oil sands reclamation projects are proposing the use of OSPW as part of reconstructed wetlands projects. This study investigated the toxicity of OSPW to freshwater invertebrates. The toxic interactions between NA and salinity on freshwater invertebrates were assessed. Bioassays with laboratory-cultured Ceriodaphnia dubia were conducted to determine the toxicity of OSPW from selected water bodies. The study showed that while the concentrations of NAs and salinity were elevated in OSPW waters that caused toxic responses, the concentrations of salinity ions varied greatly among the OSPW samples. Results of the study suggested that ion composition may be a factor in toxicity. Interactions between NAs and salinity were then assessed by performing bioassays with mixtures representing major ion combinations in OSPW.

Hormesis in Cholestatic Liver Disease; Preconditioning with Low Bile Acid Concentrations Protects against Bile Acid-Induced Toxicity.

Directory of Open Access Journals (Sweden)

Esther M Verhaag

Full Text Available Cholestasis is characterized by accumulation of bile acids and inflammation, causing hepatocellular damage. Still, liver damage markers are highest in acute cholestasis and drop when this condition becomes chronic, indicating that hepatocytes adapt towards the hostile environment. This may be explained by a hormetic response in hepatocytes that limits cell death during cholestasis.To investigate the mechanisms that underlie the hormetic response that protect hepatocytes against experimental cholestatic conditions.HepG2.rNtcp cells were preconditioned (24 h with sub-apoptotic concentrations (0.1-50 μM of various bile acids, the superoxide donor menadione, TNF-α or the Farsenoid X Receptor agonist GW4064, followed by a challenge with the apoptosis-inducing bile acid glycochenodeoxycholic acid (GCDCA; 200 μM for 4 h, menadione (50 μM, 6 h or cytokine mixture (CM; 6 h. Levels of apoptotic and necrotic cell death, mRNA expression of the bile salt export pump (ABCB11 and bile acid sensors, as well as intracellular GCDCA levels were analyzed.Preconditioning with the pro-apoptotic bile acids GCDCA, taurocholic acid, or the protective bile acids (tauroursodeoxycholic acid reduced GCDCA-induced caspase-3/7 activity in HepG2.rNtcp cells. Bile acid preconditioning did not induce significant levels of necrosis in GCDCA-challenged HepG2.rNtcp cells. In contrast, preconditioning with cholic acid, menadione or TNF-α potentiated GCDCA-induced apoptosis. GCDCA preconditioning specifically reduced GCDCA-induced cell death and not CM- or menadione-induced apoptosis. The hormetic effect of GCDCA preconditioning was concentration- and time-dependent. GCDCA-, CDCA- and GW4064- preconditioning enhanced ABCB11 mRNA levels, but in contrast to the bile acids, GW4064 did not significantly reduce GCDCA-induced caspase-3/7 activity. The GCDCA challenge strongly increased intracellular levels of this bile acid, which was not lowered by GCDCA-preconditioning.Sub-toxic

Lewis Acid-Base Chemistry of 7-Azaisoindigo-Based Organic Semiconductors.

Science.gov (United States)

Randell, Nicholas M; Fransishyn, Kyle M; Kelly, Timothy L

2017-07-26

Low-band-gap organic semiconductors are important in a variety of organic electronics applications, such as organic photovoltaic devices, photodetectors, and field effect transistors. Building on our previous work, which introduced 7-azaisoindigo as an electron-deficient building block for the synthesis of donor-acceptor organic semiconductors, we demonstrate how Lewis acids can be used to further tune the energies of the frontier molecular orbitals. Coordination of a Lewis acid to the pyridinic nitrogen of 7-azaisoindigo greatly diminishes the electron density in the azaisoindigo π-system, resulting in a substantial reduction in the lowest unoccupied molecular orbital (LUMO) energy. This results in a smaller highest occupied molecular orbital-LUMO gap and shifts the lowest-energy electronic transition well into the near-infrared region. Both H + and BF 3 are shown to coordinate to azaisoindigo and affect the energy of the S 0 → S 1 transition. A combination of time-dependent density functional theory and UV/vis and 1 H NMR spectroscopic titrations reveal that when two azaisoindigo groups are present and high concentrations of acid are used, both pyridinic nitrogens bind Lewis acids. Importantly, we demonstrate that this acid-base chemistry can be carried out at the solid-vapor interface by exposing thin films of aza-substituted organic semiconductors to vapor-phase BF 3 ·Et 2 O. This suggests the possibility of using the BF 3 -bound 7-azaisoindigo-based semiconductors as n-type materials in various organic electronic applications.

Tannic acid alleviates bulk and nanoparticle Nd2O3 toxicity in pumpkin: a physiological and molecular response.

Science.gov (United States)

Chen, Guangcai; Ma, Chuanxin; Mukherjee, Arnab; Musante, Craig; Zhang, Jianfeng; White, Jason C; Dhankher, Om Parkash; Xing, Baoshan

2016-11-01

The effect of dissolved organic matter (DOM) on nanoparticle toxicity to plants is poorly understood. In this study, tannic acid (TA) was selected as a DOM surrogate to explore the mechanisms of neodymium oxide NPs (Nd2O3 NPs) phytotoxicity to pumpkin (Cucurbita maxima). The results from the tested concentrations showed that 100 mg L(-1) Nd2O3 NPs were significantly toxic to pumpkin in term of fresh biomass, and the similar results from the bulk particles and the ionic treatments were also evident. Exposure to 100 mg L(-1) of Nd2O3 NPs and BPs in 1/5 strength Hoagland's solution not only significantly inhibited pumpkin growth, but also decreased the S, Ca, K and Mg levels in plant tissues. However, 60 mg L(-1) TA significantly moderated the observed phytotoxicity, decreased Nd accumulation in the roots, and notably restored S, Ca, K and Mg levels in NPs and BPs treated pumpkin. TA at 60 mg L(-1) increased superoxide dismutase (SOD) activity in both roots (17.5%) and leaves (42.9%), and catalase (CAT) activity (243.1%) in the roots exposed to Nd2O3 NPs. This finding was confirmed by the observed up-regulation of transcript levels of SOD and CAT in Nd2O3 NPs treated pumpkin analyzed by quantitative reverse transcription polymerase chain reaction. These results suggest that TA alleviates Nd2O3 BPs/NPs toxicity through alteration of the particle surface charge, thus reducing the contact and uptake of NPs by pumpkin. In addition, TA promotes antioxidant enzymatic activity by elevating the transcript levels of genes involved in ROS scavenging. Our results shed light on the mechanisms underlying the influence of DOM on the bioavailability and toxicity of NPs to terrestrial plants.

Methamphetamine-induced dopaminergic toxicity prevented owing to the neuroprotective effects of salicylic acid.

Science.gov (United States)

Thrash-Williams, Bessy; Karuppagounder, Senthilkumar S; Bhattacharya, Dwipayan; Ahuja, Manuj; Suppiramaniam, Vishnu; Dhanasekaran, Muralikrishnan

2016-06-01

Methamphetamine (Schedule-II drug, U.S. Drug Enforcement Administration) is one of the most abused illicit drug following cocaine, marijuana, and heroin in the USA. There are numerous health impairments and substantial economic burden caused by methamphetamine abuse. Salicylic acid, potent anti-inflammatory drug and a known neuroprotectant has shown to protect against toxicity-induced by other dopaminergic neurotoxins. Hence, in this study we investigated the neuroprotective effects of salicylic acid against methamphetamine-induced toxicity in mice. The current study investigated the effects of sodium salicylate and/or methamphetamine on oxidative stress, monoamine oxidase, mitochondrial complex I & IV activities using spectrophotometric and fluorimetric methods. Behavioral analysis evaluated the effect on movement disorders-induced by methamphetamine. Monoaminergic neurotransmitter levels were evaluated using high pressure liquid chromatography-electrochemical detection. Methamphetamine caused significant generation of reactive oxygen species and decreased complex-I activity leading to dopamine depletion. Striatal dopamine depletion led to significant behavioral changes associated with movement disorders. Sodium salicylate (50 & 100mg/kg) significantly scavenged reactive oxygen species, blocked mitochondrial dysfunction and exhibited neuroprotection against methamphetamine-induced neurotoxicity. In addition, sodium salicylate significantly blocked methamphetamine-induced behavioral changes related to movement abnormalities. One of the leading causative theories in nigral degeneration associated with movement disorders such as Parkinson's disease is exposure to stimulants, drugs of abuse, insecticide and pesticides. These neurotoxic substances can induce dopaminergic neuronal insult by oxidative stress, apoptosis, mitochondrial dysfunction and inflammation. Salicylic acid due to its antioxidant and anti-inflammatory effects could provide neuroprotection against the

Toxic Effects of Peracetic Acid Used as a Chemical Weapon During Workers Riots

International Nuclear Information System (INIS)

Jovic-Stosic, J.; Todorovic, V.; Segrt, Z.

2007-01-01

Peracetic acid (PAA) is a mixture of acetic acid and hydrogen peroxide, often used as antimicrobial agent on food processing equipment. It may explosively decompose on shock, friction or concussion. PAA is a strong oxidant, corrosive to the eyes, skin, respiratory and digestive tract. Depending on concentration, contact may cause severe burns of the skin or the eyes, and inhalation may cause lung edema. We report toxic effects of PAA used as a chemical weapon in workers riots. Group of workers attacked the security guards in beverage plant, throwing out beer bottles filled with PAA. Bottles exploded, producing irritant mists and fumes, and splashing some of the guards with acid. After about 20 minutes of exposure in the closed space, 30 persons were transported to the emergency room; 22 of them were transferred to the hospital. After the initial treatment, 10 patients were admitted for further treatment. The symptoms of exposure included burning sensation and pain of the eyes, throat and skin, cough and shortness of breath. Effects on the eyes included redness and corneal erosions. Pulmonary disturbances were prolonged expirium and wheezing by auscultation, and hypoxemia. Skin burns were ranged as grade I-III. Treatment included rinse of eyes and skin, systemic therapy with corticosteroids, beta adrenergic drugs and theophylline. Surgical treatment was necessary in grade III skin burns. A variety of common industrial chemicals may be misused as a chemical weapon. We point out the hazards of serious toxic effects of PAA if used in riots or terrorists attacks. (author)

In vivo assessment of toxicity and pharmacokinetics of methylglyoxal

International Nuclear Information System (INIS)

Ghosh, Manju; Talukdar, Dipa; Ghosh, Swapna; Bhattacharyya, Nivedita; Ray, Manju; Ray, Subhankar

2006-01-01

Previous in vivo studies from several laboratories had shown remarkable curative effect of methylglyoxal on cancer-bearing animals. In contrast, most of the recent in vitro studies have assigned a toxic role for methylglyoxal. The present study was initiated with the objective to resolve whether methylglyoxal is truly toxic in vivo and to reassess its therapeutic potential. Four species of animals, both rodent and non-rodent, were treated with different doses of methylglyoxal through oral, subcutaneous and intravenous routes. Acute (treatment for only 1 day) toxicity tests had been done with mouse and rat. These animals received 2, 1 and 0.3 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. Chronic (treatment for around a month) toxicity test had been done with mouse, rat, rabbit and dog. Mouse, rat and dog received 1, 0.3 and 0.1 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. Rabbit received 0.55, 0.3 and 0.1 g of methylglyoxal/kg of body weight in a day through oral, subcutaneous and intravenous routes respectively. It had been observed that methylglyoxal had no deleterious effect on the physical and behavioral pattern of the treated animals. Fertility and teratogenecity studies were done with rats that were subjected to chronic toxicity tests. It had been observed that these animals produced healthy litters indicating no damage of the reproductive systems as well as no deleterious effect on the offspring. Studies on several biochemical and hematological parameters of methylglyoxal-treated rats and dogs and histological studies of several organs of methylglyoxal-treated mouse were performed. These studies indicated that methylglyoxal had no apparent deleterious effect on some vital organs of these animals. A detailed pharmacokinetic study was done with mouse after oral administration of methylglyoxal. The effect of methylglyoxal alone and in

High-grade acute organ toxicity as positive prognostic factor in primary radio(chemo)therapy for locally advanced, inoperable head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Wolff, Hendrik Andreas; Bosch, Jan; Hennies, Steffen; Hess, Clemens F.; Christiansen, Hans [Dept. of Radiotherapy and Radiooncology, Univ. Medicine Goettingen (Germany); Jung, Klaus [Dept. of Medical Statistics, Univ. Medicine Goettingen (Germany); Overbeck, Tobias [Dept. of Haematology and Oncology, Univ. Medicine Goettingen (Germany); Matthias, Christoph; Roedel, Ralph M. [Dept. of Otorhinolaryngology, Univ. Medicine Goettingen (Germany)

2010-05-15

Purpose: to test for a possible correlation between high-grade acute organ toxicity during primary radio(chemo)therapy and treatment outcome in patients with locally advanced head and neck squamous cell carcinoma (HNSCC). Patients and methods: from 05/1994 to 01/2009, 216 HNSCC patients were treated with radio(chemo)therapy in primary approach. They received normofractionated (2 Gy/fraction) irradiation including associated nodal drainage sites to a cumulative dose of 70 Gy. 151 patients received additional concomitant chemotherapy (111 patients 5-fluorouracil/mitomycin C, 40 patients cisplatin-based). Toxicity during treatment was monitored weekly according to the Common Toxicity Criteria (CTC), and any toxicity grade CTC {>=} 3 of mucositis, dysphagia or skin reaction was assessed as high-grade acute organ toxicity for later analysis. Results: a statistically significant coherency between high-grade acute organ toxicity and overall survival as well as locoregional control was found: patients with CTC {>=} 3 acute organ toxicity had a 5-year overall survival rate of 4% compared to 8% in patients without (p < 0.01). Thereby, multivariate analyses revealed that the correlation was independent of other possible prognostic factors or factors that may influence treatment toxicity, especially concomitant chemotherapy and radiotherapy technique or treatment-planning procedure. Conclusion: these data indicate that normal tissue and tumor tissue may behave similarly with respect to treatment response, as high-grade acute organ toxicity during radio(chemo)therapy showed to be an independent prognostic marker in the own patient population. However, the authors are aware of the fact that a multivariate analysis in a retrospective study generally has statistical limitations. Therefore, their hypothesis should be further analyzed on biomolecular and clinical levels and other tumor entities in prospective trials. (orig.)

Toxic Byproduct Formation during Electrochemical Treatment of Latrine Wastewater.

Science.gov (United States)

Jasper, Justin T; Yang, Yang; Hoffmann, Michael R

2017-06-20

Electrochemical systems are an attractive option for onsite latrine wastewater treatment due to their high efficiency and small footprint. While concerns remain over formation of toxic byproducts during treatment, rigorous studies examining byproduct formation are lacking. Experiments treating authentic latrine wastewater over variable treatment times, current densities, chloride concentrations, and anode materials were conducted to characterize byproducts and identify conditions that minimize their formation. Production of inorganic byproducts (chlorate and perchlorate) and indicator organic byproducts (haloacetic acids and trihalomethanes) during electrolysis dramatically exceeded recommendations for drinking water after one treatment cycle (∼10-30 000 times), raising concerns for contamination of downstream water supplies. Stopping the reaction after ammonium was removed (i.e., the chlorination breakpoint) was a promising method to minimize byproduct formation without compromising disinfection and nutrient removal. Though treatment was accelerated at increased chloride concentrations and current densities, byproduct concentrations remained similar near the breakpoint. On TiO 2 /IrO 2 anodes, haloacetic acids (up to ∼50 μM) and chlorate (up to ∼2 μM) were of most concern. Although boron-doped diamond anodes mineralized haloacetic acids after formation, high production rates of chlorate and perchlorate (up to ∼4 and 25 μM) made them inferior to TiO 2 /IrO 2 anodes in terms of toxic byproduct formation. Organic byproduct formation was similar during chemical chlorination and electrolysis of wastewater, suggesting that organic byproducts are formed by similar pathways in both cases (i.e., reactions with chloramines and free chlorine).

Physical and chemical parameters of sediment extraction and fractionation that influence toxicity, as evaluated by microtox (trade name)

International Nuclear Information System (INIS)

Ho, K.T.Y.; Quinn, J.G.

1993-01-01

Several physical and chemical parameters of sediment extraction and fractionation of organic compounds that influence bioassay results were evaluated. Each parameter was evaluated with a photoluminescent bacterial bioassay (Microtox) as an end point. Three solvents (acetonitrile, acetone, and methanol) were studied for their ability to extract toxic organic components from marine sediments. Acetone extracted the most toxicity, with no difference between acetonitrile and methanol. Two methods of fractionating sediment extracts (silica-gel-column chromatography (SGCC) and acid-base fractionation) were compared. SGCC was more useful because it resulted in a wider range of responses and was faster to perform than acid-base fractionation. Microtox was used to rank four marine sediments with respect to toxicity and to determine if one chemical class (or fraction) was consistently more toxic among different sediments. With some caveats, Microtox results agreed with general chemical concentration trends and other bioassay results in distinguishing between contaminated and noncontaminated sediments. Although results indicated there was not a consistently most toxic fraction among sediments, there was a consistently least toxic fraction. The effect of sediment storage time on toxicity was also evaluated. Results indicated that the most stable chemical fraction (containing nonpolar hydrocarbons) did not change toxicologically for 30 weeks, whereas the more chemically active fraction (containing ketones, quinones, and carboxyls) changed as soon as one week

[Effects of low molecular weight organic acids on redox reactions of mercury].

Science.gov (United States)

Zhao, Shi-Bo; Sun, Rong-Guo; Wang, Ding-Yong; Wang, Xiao-Wen; Zhang, Cheng

2014-06-01

To study the effects of the main component of vegetation root exudates-low molecular weight organic acids on the redox reactions of mercury, laboratory experiments were conducted to investigate the roles of tartaric, citric, and succinic acid in the redox reactions of mercury, and to analyze their interaction mechanism. The results indicated that tartaric acid significantly stimulated the mercury reduction reaction, while citric acid had inhibitory effect. Succinic acid improved the reduction rate at low concentration, and inhibited the reaction at high concentration. The mercury reduction rate by tartaric acid treatment was second-order with respect to Hg2+ concentration, ranging from 0.0014 L x (ng x min)(-1) to 0.005 6 L x (ng x min)(-1). All three organic acids showed a capacity for oxidating Hg(0) in the early stage, but the oxidized Hg(0) was subsequently reduced. The oxidation capacity of the three organic acids was in the order of citric acid > tartaric acid > succinic acid.

The Acid-Base Balance Between Organic Acids and Circumneutral Ground Waters in Large Peatlands

Science.gov (United States)

Siegel, D. I.; Glaser, P. H.; So, J.

2006-05-01

Organic acids supply most of the acidity in the surface waters of bogs in peatlands. Yet, the fundamental geochemical properties of peatland organic acids are still poorly known. To assess the geochemical properties of typical organic acid assemblages in peatlands, we used a triprotic analog model for peat pore waters and surface waters in the Glacial Lake Agassiz Peatlands, optimizing on charge balance and calibrated to estimates of mole site density in DOC and triprotic acid dissociation constants. Before the calibration process, all bog waters and 76% of fen waters had more than +20% charge imbalance. After calibration, most electrochemically balanced within 20%. In the best calibration, the mole site denisty of bog DOC was estimated as ~0.05 mmol/mmol C., approximately 6 times smaller than that for fen DOC or the DOC in the fen deeper fen peats that underlie bogs. The three modeled de-protonation constants were; pKa1 = ~3.0, pKa2 = ~4.5 and pKa3 = ~7.0 for the bog DOC, and; pKa1 = ~5.2, pKa2 =~ 6.5 and pKa3 = ~7.0 for the fen DOC. Bog DOC, behaves as a strong acid despite its small mole site density. The DOC in bog runoff can therefore theoretically acidify the surface waters in adjacent fens wherever these waters do not receive sufficient buffering alkalinity from active groundwater seepage.

Pretreatment and fermentation strategies to overcome the toxicity of acetic acid in hemicellulosic hydrolysates

DEFF Research Database (Denmark)

Mussatto, Solange I.

Acetic acid is one of the most important toxic compounds present in hemicellulosic hydrolysates. In order to overcome this problem, several strategies were studied for both biomass pretreatment and fermentation steps. Biomass deacetylation by mild alkaline pretreatment or using high pressure CO2...... where acetic acid can also be integrated as a valuable final product. For the fermentation step, it is well known that hemicellulosic hydrolysates usually need to be detoxified prior use as fermentation medium in order to improve the performance of the microorganism to convert sugars in the product...... of interest. Although detoxification improves the fermentability of hydrolysates, this additional step adds cost and complexity to the process and generates extra waste products. In this sense, the adaptation of the fermenting microorganism to increased concentrations of acetic acid can be considered...

Toxic organic compounds from energy production

Energy Technology Data Exchange (ETDEWEB)

Hites, R.A.

1991-09-20

The US Department of Energy's Office of Health and Environmental Research (OHER) has supported work in our laboratory since 1977. The general theme of this program has been the identification of potentially toxic organic compounds associated with various combustion effluents, following the fates of these compounds in the environment, and improving the analytical methodology for making these measurements. The projects currently investigation include: an improved sampler for semi-volatile compounds in the atmosphere; the wet and dry deposition of dioxins and furans from the atmosphere; the photodegradation and mobile sources of dioxins and furans; and the bioaccumulation of PAH by tree bark. These projects are all responsive to OHER's interest in the pathways and mechanisms by which energy-related agents move through and are modified by the atmosphere''. The projects on gas chromatographic and liquid chromatographic tandem mass spectrometry are both responsive to OHER's interest in new and more sensitive technologies for chemical measurements''. 35 refs., 9 figs.

Use of organic acids to inactivate Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on organic fresh apples and lettuce.

Science.gov (United States)

Park, Sang-Hyun; Choi, Mi-Ran; Park, Jeong-Woong; Park, Ki-Hwan; Chung, Myung-Sub; Ryu, Sangryeol; Kang, Dong-Hyun

2011-08-01

This study was undertaken to investigate the antimicrobial effect of organic acids against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on whole red organic apples and lettuce. Several studies have been conducted to evaluate organic acids as sanitizers. However, no studies have compared antimicrobial effects of various organic acids on organic fresh produce, including evaluation of color changes of produce. Apples and lettuce were inoculated with a cocktail of 3 strains each of 3 foodborne pathogens provided above and treated with 1% and 2% organic acids (propionic, acetic, lactic, malic, and citric acid) for 0, 0.5, 1, 5, and 10 min. With increasing treatment time and acid concentration, organic acid treatments showed significant reduction compared to the control treatment (distilled water), and differences in antimicrobial effects between organic acids were observed. After 10 min of treatment with 1% and 2% organic acids in apples, propionic (0.92 to 2.75 log reduction), acetic (0.52 to 2.78 log reduction), lactic (1.69 to >3.42 log reduction), malic (1.48 to >3.42 log reduction), and citric acid (1.52 to >3.42 log reduction) exhibited significant (P acid (1.85 to 2.86 log reduction) showed significant (P acids treatment were not significant during storage. It is suggested that organic acids have a potential as sanitizers for organic fresh produce. These data may help the organic produce industry provide safe fresh produce for consumers. © 2011 Institute of Food Technologists®

Nanomaterial translocation - the biokinetics, tissue accumulation, toxicity and fate of materials in secondary organs

DEFF Research Database (Denmark)

Kermanizadeh, Ali; Balharry, Dominique; Wallin, Håkan

2015-01-01

into the toxicity posed by the NMs in these secondary organs is expanding due to the realisation that some materials may reach and accumulate in these target sites. The translocation to secondary organs includes, but is not limited to, the hepatic, central nervous, cardiovascular and renal systems. Current data...... dioxide and quantum dots) or fast (e.g. zinc oxide) solubility. The translocation of NMs following intratracheal, intranasal and pharyngeal aspiration is higher (up to 10% of administered dose), however the relevance of these routes for risk assessment is questionable. Uptake of the materials from....... For toxicological and risk evaluation, further information on the toxicokinetics and persistence of NMs is crucial. The overall aim of this review is to outline the data currently available in the literature on the biokinetics, accumulation, toxicity and eventual fate of NMs in order to assess the potential risks...

Toxicity of anti-fouling paints for use on ships and leisure boats to non-target organisms representing three trophic levels

International Nuclear Information System (INIS)

Karlsson, Jenny; Ytreberg, Erik; Eklund, Britta

2010-01-01

Leachates of anti-fouling paints for use on ships and leisure boats are examined for their ecotoxicological potential. Paint leachates were produced in both 7 per mille artificial (ASW) and natural seawater (NSW) and tested on three organisms, the bacterium Vibrio fischeri, the macroalga Ceramium tenuicorne, and the crustacean Nitocra spinipes. Generally, leaching in ASW produced a more toxic leachate and was up to 12 times more toxic to the organisms than was the corresponding NSW leachate. The toxicity could be explained by elevated concentrations of Cu and Zn in the ASW leachates. Of the NSW leachates, those from the ship paints were more toxic than those from leisure boat paints. The most toxic paint was the biocide-free leisure boat paint Micron Eco. This implies that substances other than added active agents (biocides) were responsible for the observed toxicity, which would not have been discovered without the use of biological tests. - Leachate from a biocide-free anti-fouling paint for leisure boat use was more toxic than leachates from ship paints.

Performance investigation of low-toxic organic corrosion inhibitors in amine treating unit

International Nuclear Information System (INIS)

Veawab, A.; Tanthapanichakoon, W.

2003-01-01

Amine treating unit is constantly subject to severe corrosion problems leading to extra expenditure and operational limitations. Heavy-metal vanadium compounds are extensively used as corrosion inhibitors to suppress the severe corrosion to an acceptable level. In recent years, the fact that these vanadium compounds are inherently toxic and can potentially pose adverse impacts on the human health and the environment has brought about environmental awareness that causes their uses costly due to the difficulty in waste disposal. To respond to the environmental concern and reduce cost of waste disposal as well as prepare for more stringent regulations for chemical uses, the development of low-toxic corrosion inhibitors is necessary. This work therefore focuses on an investigation of inhibition performance of a number of organic and inorganic compounds that have relatively low toxicity in comparison with conventional inhibitors. The performance evaluation was carried out through corrosion experiments using carbon steel specimens. The experiments were done in 3 and 5 kmol/m 3 monoethanolamine (MEA) solution saturated with CO 2 at 80 o C. It was found that several tested compounds have potential to be effective low-toxic corrosion inhibitors. The promising compounds provide reasonable and in some cases comparable protection performance to the conventional inhibitor. (author)

The non-participation of organic sulphur in acid mine drainage generation.

Science.gov (United States)

Casagrande, D J; Finkelman, R B; Caruccio, F T

1989-12-01

Acid mine drainage is commonly associated with land disturbances that encounter and expose iron sulphides to oxidising atmospheric conditions. The attendant acidic conditions solubilise a host of trace metals. Within this flow regime the potential exists to contaminate surface drinking water supplies with a variety of trace materials. Accordingly, in evaluating the applications for mines located in the headwaters of water sheds, the pre-mining prediction of the occurrence of acid mine drainage is of paramount importance.There is general agreement among investigators that coal organic sulphur is a nonparticipant in acid mine drainage generation; however, there is no scientific documentation to support this concensus. Using simulated weathering, kinetic, mass balance, petrographic analysis and a peroxide oxidation procedure, coal organic sulphur is shown to be a nonparticipant in acid mine drainage generation. Calculations for assessing the acid-generating potential of a sedimentary rock should not include organic sulphur content.

Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination.

Science.gov (United States)

Bai, Shahla Hosseini; Ogbourne, Steven M

2016-10-01

Glyphosate has been the most widely used herbicide during the past three decades. The US Environmental Protection Agency (EPA) classifies glyphosate as 'practically non-toxic and not an irritant' under the acute toxicity classification system. This classification is based primarily on toxicity data and due to its unique mode of action via a biochemical pathway that only exists in a small number of organisms that utilise the shikimic acid pathway to produce amino acids, most of which are green plants. This classification is supported by the majority of scientific literature on the toxic effects of glyphosate. However, in 2005, the Food and Agriculture Organisation (FAO) reported that glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), are of potential toxicological concern, mainly as a result of accumulation of residues in the food chain. The FAO further states that the dietary risk of glyphosate and AMPA is unlikely if the maximum daily intake of 1 mg kg(-1) body weight (bw) is not exceeded. Research has now established that glyphosate can persist in the environment, and therefore, assessments of the health risks associated with glyphosate are more complicated than suggested by acute toxicity data that relate primarily to accidental high-rate exposure. We have used recent literature to assess the possible risks associated with the presence of glyphosate residues in food and the environment.

Uric Acid Spherulites in the Reflector Layer of Firefly Light Organ

Science.gov (United States)

Goh, King-Siang; Sheu, Hwo-Shuenn; Hua, Tzu-En; Kang, Mei-Hua; Li, Chia-Wei

2013-01-01

Background In firefly light organs, reflector layer is a specialized tissue which is believed to play a key role for increasing the bioluminescence intensity through reflection. However, the nature of this unique tissue remains elusive. In this report, we investigated the role, fine structure and nature of the reflector layer in the light organ of adult Luciola cerata. Principal Findings Our results indicated that the reflector layer is capable of reflecting bioluminescence, and contains abundant uric acid. Electron microscopy (EM) demonstrated that the cytosol of the reflector layer's cells is filled with densely packed spherical granules, which should be the uric acid granules. These granules are highly regular in size (∼700 nm in diameter), and exhibit a radial internal structure. X-ray diffraction (XRD) analyses revealed that an intense single peak pattern with a d-spacing value of 0.320 nm is specifically detected in the light organ, and is highly similar to the diffraction peak pattern and d-spacing value of needle-formed crystals of monosodium urate monohydrate. However, the molar ratio evaluation of uric acid to various cations (K+, Na+, Ca2+ and Mg2+) in the light organ deduced that only a few uric acid molecules were in the form of urate salts. Thus, non-salt uric acid should be the source of the diffraction signal detected in the light organ. Conclusions In the light organ, the intense single peak diffraction signal might come from a unique needle-like uric acid form, which is different from other known structures of non-salt uric acid form. The finding of a radial structure in the granules of reflector layer implies that the spherical uric acid granules might be formed by the radial arrangement of needle-formed packing matter. PMID:23441187

The role of calcium, silicon and salicylic acid treatment in protection of canola plants against boron toxicity stress.

Science.gov (United States)

Metwally, Ashraf M; Radi, Abeer A; El-Shazoly, Rasha M; Hamada, Afaf M

2018-01-22

Boron (B) toxicity often limits crop yield and the quality of production in agricultural areas. Here, we investigated the effects of calcium (Ca), silicon (Si) and salicylic acid (SA) on development of B toxicity, B allocation in canola (Brassica napus cultivar Sarw 4) and its role in non-enzymatic antioxidants in relation to yield of this cultivar under B toxicity. Canola seedlings were subjected to four B levels induced by boric acid in the absence or presence of Ca, Si and SA. The results showed that Ca, Si and SA addition ameliorated the inhibition in canola growth, water content (WC), and improved siliqua number, siliqua weight and seed index. The B content in shoots and roots and total B accumulation in the whole plant were increased in control plants under B-toxicity-stress, and these parameters were significantly decreased by addition of Ca, Si and SA. The shoot ascorbate pool (ascorbate, AsA, and dehydroascorbate, DHA), α-tocopherol and phenolics (free and bound) were increased under B toxicity, and were significantly decreased in most cases by addition of Ca, Si and SA, except α-tocopherol, which increased at low B levels (0, 25 and 50 mg kg soil -1 ). The glutathione content did not obviously change by B stress, while added Ca, Si and SA inhibited its accumulation under B stress. In addition, B toxicity reduced the shoot flavonoids content; however, this reduction was not alleviated by the use of Ca, Si and SA treatments. It could be concluded that growth and yield of canola plants grown under high B concentration improved after external application of Ca, Si or SA.

Effect of Soil Filtration and Ozonation in the Change of Baseline Toxicity in Wastewater Spiked with Organic Micro-pollutants

KAUST Repository

Gan, Alexander

2012-07-01

Bioassays for baseline toxicity, which measure toxicants’ non-specific effects, have been shown in previous studies to effectively correlate with the increased presence of pharmaceuticals, personal care products, endocrine-disrupting compounds, and other synthetic organics in treated sewage effluent. This study investigated how the baseline toxicity of anthropogenic compounds-spiked wastewater changed during the treatment of biofiltration and ozone oxidation, as measured by the bioluminescence inhibition of the Vibrio fischeri bacterium. The water quality parameters of dissolved organic carbon, seven common anions, and fluorescence spectroscopy were used to corroborate and collate with the toxicity results. Water quality was evaluated on two bench-scale soil filtration columns, which were configured for pre-ozonation and post-ozonation. Both systems’ soil aerobically removed similar amounts of dissolved organic carbon, and the reduction ranged between 57.7% and 62.1% for the post-ozonation and pre-ozonation systems, respectively. Biological removal of DOC, protein-like, humic-like, and soluble microbial product-like material was highest in the first 28.5 cm of each 114 cm-long system. While bioluminescence inhibition showed that ozonation was effective at lowering baseline toxicity, this study’s bioassay procedure was a very poor indicator of soil filtration treatment; both system’s effluents were significantly more toxic than their non-ozonated influents.

Biochar: a green sorbent to sequester acidic organic contaminants

Science.gov (United States)

Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

2015-04-01

Biochar is a carbon rich product of biomass pyrolysis that exhibits a high sorption potential towards a wide variety of inorganic and organic contaminants. Because it is a valuable soil additive and a potential carbon sink that can be produced from renewable resources, biochar has gained growing attention for the development of more sustainable remediation strategies. A lot of research efforts have been dedicated to the sorption of hydrophobic contaminants and metals to biochar. Conversely, the understanding of the sorption of acidic organic contaminants remains limited, and questions remain on the influence of biochar characteristics (e.g. ash content) on the sorption behaviour of acidic organic contaminants. To address this knowledge gap, sorption batch experiments were conducted with a series of structurally similar acidic organic contaminants covering a range of dissociation constant (2,4-D, MCPA, 2,4-DB and triclosan). The sorbents selected for experimentation included a series of 10 biochars covering a range of characteristics, multiwalled carbon nanotubes as model for pure carbonaceous phases, and an activated carbon as benchmark. Overall, sorption coefficient [L/kg] covered six orders of magnitude and generally followed the order 2,4-D pH dependent lipophilicity ratio (i.e. D instead of Kow), ash content and ionic strength are key factors influencing the sorption of acidic organic contaminants to biochars. Overall, the identified factors, as well as the environmental matrix, should be carefully considered when selecting the type of biochar for sequestration purposes.

Fermentation process for the production of organic acids

Science.gov (United States)

Hermann, Theron; Reinhardt, James; Yu, Xiaohui; Udani, Russell; Staples, Lauren

2018-05-01

This invention relates to improvements in the fermentation process used in the production of organic acids from biological feedstock using bacterial catalysts. The improvements in the fermentation process involve providing a fermentation medium comprising an appropriate form of inorganic carbon, an appropriate amount of aeration and a biocatalyst with an enhanced ability to uptake and assimilate the inorganic carbon into the organic acids. This invention also provides, as a part of an integrated fermentation facility, a novel process for producing a solid source of inorganic carbon by sequestering carbon released from the fermentation in an alkali solution.

Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

Energy Technology Data Exchange (ETDEWEB)

Chattopadhyay, P; Pandey, A; Goyary, D; Chaurasia, A; Singh, L; Veer, V. [Division of Pharmaceutical Technology, Defence Research Laboratory, Assam (India); Department of Life Sciences, Defense Research Development and Organization, New Delhi (India)

2012-07-01

The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m ({sup 99m} Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of {sup 99m}Tc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation. (author)

Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

Directory of Open Access Journals (Sweden)

P Chattopadhyay

2012-01-01

Full Text Available The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma-scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation.

Acid-resistant organic coatings for the chemical industry: a review

DEFF Research Database (Denmark)

Møller, Victor Buhl; Dam-Johansen, Kim; Frankær, Sarah Maria Grundahl

2017-01-01

Industries that work with acidic chemicals in their processes need to make choices on how to properly contain the substances and avoid rapid corrosion of equipment. Certain organic coatings and linings can be used in such environments, either to protect vulnerable construction materials, or......, in combination with fiber reinforcement, to replace them. However, degradation mechanisms of organic coatings in acid service are not thoroughly understood and relevant quantitative investigations are scarce. This review describes the uses and limitations of acid-resistant coatings in the chemical industry...

Nutritional value of organic acid lime juice (Citrus latifolia T., cv. Tahiti

Directory of Open Access Journals (Sweden)

Carolina Netto Rangel

2011-12-01

Full Text Available Acid lime can be used as fresh fruit or as juice to increase the flavor of drinks. Therefore, it is necessary to analyze organic acid lime nutritional composition in order to evaluate if there are important differences among those conventionally produced. No significant differences in total titrable acidity, pH, ascorbic acid, sucrose, calcium, and zinc were found between the acid lime juice from organic biodynamic crops and conventional crops. However, the organic biodynamic fruits presented higher peel percentage than the conventional ones leading to lower juice yield. On the other hand, fructose, glucose, total soluble solids contents, potassium, manganese, iron, and copper were higher in the conventional samples. These results indicated few nutritional differences between organic and conventional acid lime juices in some constituents. Nevertheless, fruit juice from biodynamic crops could be a good choice since it is free from pesticides and other agents that cause problems to human health maintaining the levels similar to those of important nutritional compounds.

Soil properties influence kinetics of soil acid phosphatase in response to arsenic toxicity.

Science.gov (United States)

Wang, Ziquan; Tan, Xiangping; Lu, Guannan; Liu, Yanju; Naidu, Ravi; He, Wenxiang

2018-01-01

Soil phosphatase, which plays an important role in phosphorus cycling, is strongly inhibited by Arsenic (As). However, the inhibition mechanism in kinetics is not adequately investigated. In this study, we investigated the kinetic characteristics of soil acid phosphatase (ACP) in 14 soils with varied properties, and also explored how kinetic properties of soil ACP changed with different spiked As concentrations. The results showed that the Michaelis constant (K m ) and maximum reaction velocity (V max ) values of soil ACP ranged from 1.18 to 3.77mM and 0.025-0.133mMh -1 in uncontaminated soils. The kinetic parameters of soil ACP in different soils changed differently with As contamination. The K m remained unchanged and V max decreased with increase of As concentration in most acid and neutral soils, indicating a noncompetitive inhibition mechanism. However, in alkaline soils, the K m increased linearly and V max decreased with increase of As concentration, indicating a mixed inhibition mechanism that include competitive and noncompetitive. The competitive inhibition constant (K ic ) and noncompetitive inhibition constant (K iu ) varied among soils and ranged from 0.38 to 3.65mM and 0.84-7.43mM respectively. The inhibitory effect of As on soil ACP was mostly affected by soil organic matter and cation exchange capacity. Those factors influenced the combination of As with enzyme, which resulted in a difference of As toxicity to soil ACP. Catalytic efficiency (V max /K m ) of soil ACP was a sensitive kinetic parameter to assess the ecological risks of soil As contamination. Copyright © 2017 Elsevier Inc. All rights reserved.

Seasonal measurements of organic acid fluxes over a ponderosa pine forest

Science.gov (United States)

Fulgham, S. R.; Brophy, P.; Link, M.; Ortega, J. V.; Farmer, D.

2016-12-01

The biosphere acts as both a source and a sink of oxidized organic compounds. Ignoring dry deposition leads to overestimation of secondary organic aerosols by aerosol models, while ignoring emission sources underestimates the budget of organic acids. Developing parameterizations for oxidized organic dry deposition and emission requires observational constraints. Although biosphere parameters are impacted by seasonal variability, most reactive, trace-gas exchange measurements are made for only short periods of time in the main growing season. Here we make fast (5 - 10 Hz) and sensitive (e.g. 0.73 ppt mean limit of detection for formic acid with 10 s averaging) eddy covariance measurements of gas-phase organic acids and other oxidized organic species with a high resolution Time-of-Flight Chemical Ionization Mass Spectrometer with acetate and iodide reagent ions. Measurements were made in 4 - 6 week campaigns over five seasons from summer 2015 to fall 2016 as part of the Seasonal Particles in Forests Flux studY (SPIFFY) at the Manitou Experimental Forest Observatory near Woodland Park, Colorado. Permeation tubes were used for online calibration of carboxylic acids including formic (C1), propionic (C3), butyric (C4), methacrylic (CH2C(CH3)COOH), valeric (C5), and heptanoic (C7) acids. Average daytime mixing ratios for formic acid were 100 ± 100 ppt in winter and 1500 ± 1000 ppt in summer 2016. Upward fluxes of formic acid were observed throughout the experiment, daytime averages and standard deviations ranging from 1900 ± 1000 ppt cm s-1 in winter to 170 ± 130 ppt cm s-1 in spring. Propionic (22 ± 22 ppt cm s-1), butyric (17 ± 16 ppt cm s-1), and methacrylic (3.5 ± 6.1 ppt cm s-1) acids exhibit a mix of upward, near-zero, and downward fluxes. Fluxes were exponentially correlated to temperature, suggesting an ecosystem-scale source of these acids. We also measure exchange velocities of a broad suite of other oxidized organic compounds (31.99 m/z to 311.523 m/z in

Individual and combined effects of organic, toxic, and hydraulic shocks on sequencing batch reactor in treating petroleum refinery wastewater

Energy Technology Data Exchange (ETDEWEB)

Mizzouri, Nashwan Sh., E-mail: nashwan_mizzouri@yahoo.com [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Department of Civil Engineering, University of Duhok, Kurdistan (Iraq); Shaaban, Md Ghazaly [Department of Civil Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

2013-04-15

Highlights: ► This research focuses on the combined impact of shock loads on the PRWW treatment. ► System failure resulted when combined shock of organic and hydraulic was applied. ► Recovery was achieved by replacing glucose with PRWW and OLR was decreased to half. ► Worst COD removals were 68.9, and 57.8% for organic, and combined shocks. -- Abstract: This study analyzes the effects of toxic, hydraulic, and organic shocks on the performance of a lab-scale sequencing batch reactor (SBR) with a capacity of 5 L. Petroleum refinery wastewater (PRWW) was treated with an organic loading rate (OLR) of approximately 0.3 kg chemical oxygen demand (COD)/kg MLSS d at 12.8 h hydraulic retention time (HRT). A considerable variation in the COD was observed for organic, toxic, hydraulic, and combined shocks, and the worst values observed were 68.9, 77.1, 70.2, and 57.8%, respectively. Improved control of toxic shock loads of 10 and 20 mg/L of chromium (VI) was identified. The system was adversely affected by the organic shock when a shock load thrice the normal value was used, and this behavior was repeated when the hydraulic shock was 4.8 h HRT. The empirical recovery period was greater than the theoretical period because of the inhibitory effects of phenols, sulfides, high oil, and grease in the PRWW. The system recovery rates from the shocks were in the following order: toxic, organic, hydraulic, and combined shocks. System failure occurred when the combined shocks of organic and hydraulic were applied. The system was resumed by replacing the PRWW with glucose, and the OLR was reduced to half its initial value.

Acoustic properties of organic acid mixtures in water

Science.gov (United States)

Macavei, I.; Petrisor, V.; Auslaender, D.

1974-01-01

The variation of the rate of propagation of ultrasounds in organic acid mixtures in water points to structural changes caused by interactions that take place under conditions of thermal agitation, at different acid concentrations. At the same time, a difference is found in the changes in velocity as a function of the length of the carbon chain of the acids in the mixture as a result of their effect on the groups of water molecules associated by hydrogen bonds.

Effect of acidic seed on biogenic secondary organic aerosol growth

Science.gov (United States)

Czoschke, Nadine M.; Jang, Myoseon; Kamens, Richard M.

Secondary organic aerosol (SOA) growth in the presence of acid aerosols was studied in twin 500 l Teflon bags and in a 4 m flow reactor. In Teflon bags, isoprene, acrolein and α-pinene were all made to react individually with ozone and exposed to either acid or non-acid inorganic seed aerosols to determine the effect of acid-catalyzed heterogeneous reactions on SOA growth. α-Pinene and ozone were made to react in a flow reactor to assess the immediate effect of mixing an acid aerosol with SOA at high and low relative humidity levels. In all cases, exposure to acid seed aerosol increased the amount of SOA mass produced. Fourier transform infrared spectra of the SOA in acid systems confirmed the transformation of carbonyl functional groups through acid-catalyzed heterogeneous reactions when SOAs formed in acidic environments or were exposed to acidic aerosols. Organic products initially produced from ozonation in the gas phase partition onto the inorganic seed aerosol and react heterogeneously with an acid catalyst forming low vapor pressure products. These acid-catalyzed heterogeneous reactions are implicated in generating the increased SOA mass observed in acidic aerosol systems as they transform predominantly gas phase compounds of high volatility into low vapor pressure predominantly particle phase products.

Sub-chronic toxicity of low concentrations of industrial volatile organic pollutants in vitro

International Nuclear Information System (INIS)

McDermott, Catherine; Allshire, Ashley; Pelt, Frank N.A.M. van; Heffron, James J.A.

2007-01-01

Organic solvents form an important class of pollutants in the ambient air and have been associated with neurotoxicity and immunotoxicity in humans. Here we investigated the biological effects of sub-chronic exposure to industrially important volatile organic solvents in vitro. Jurkat T cells were exposed to toluene, n-hexane and methyl ethyl ketone (MEK) individually for 5 days and solvent exposure levels were confirmed by headspace gas chromatography. A neuroblastoma cell line (SH-SY5Y) was exposed to toluene for the same period. Following exposure, cells were harvested and toxicity measured in terms of the following endpoints: membrane damage (LDH leakage), perturbations in intracellular free Ca 2+ , changes in glutathione redox status and dual-phosphorylation of MAP kinases ERK1/2, JNK and p38. The results show that sub-chronic exposure to the volatile organic solvents causes membrane damage, increased intracellular free calcium and altered glutathione redox status in both cell lines. However, acute and sub-chronic solvent exposure did not result in MAP kinase phosphorylation. Toxicity of the solvents tested increased with hydrophobicity. The lowest-observed-adverse-effect-levels (LOAELs) measured in vitro were close to blood solvent concentrations reported for individuals exposed to the agents at levels at or below their individual threshold limit values (TLVs)

Modeling the acid-base chemistry of organic solutes in Adirondack, New York, lakes

Science.gov (United States)

Driscoll, Charles T.; Lehtinen, Michael D.; Sullivan, Timothy J.

1994-02-01

Data from the large and diverse Adirondack Lake Survey were used to calibrate four simple organic acid analog models in an effort to quantify the influence of naturally occurring organic acids on lake water pH and acid-neutralizing capacity (ANC). The organic acid analog models were calibrated to observations of pH, dissolved organic carbon (DOC), and organic anion (An-) concentrations from a reduced data set representing 1128 individual lake samples, expressed as 41 observations of mean pH, in intervals of 0.1 pH units from pH 3.9 to 7.0. Of the four organic analog approaches examined, including the Oliver et al. (1983) model, as well as monoprotic, diprotic, and triprotic representations, the triprotic analog model yielded the best fit (r2 = 0.92) to the observed data. Moreover, the triprotic model was qualitatively consistent with observed patterns of change in organic solute charge density as a function of pH. A low calibrated value for the first H+ dissociation constant (pKal = 2.62) and the observation that organic anion concentrations were significant even at very low pH (acidic functional groups. Inclusion of organic acidity in model calculations resulted in good agreement between measured and predicted values of lake water pH and ANC. Assessments to project the response of surface waters to future changes in atmospheric deposition, through the use of acidification models, will need to include representations of organic acids in model structure to make accurate predictions of pH and ANC.

Method of processing radiation-contaminated organic polymer materials

International Nuclear Information System (INIS)

Kobayashi, Yoshii.

1980-01-01

Purpose: To process radiation contaminated organic high polymer materials with no evolution of toxic gases, at low temperature and with safety by hot-acid immersion process using sulfuric acid-hydrogen peroxide. Method: Less flammable or easily flammable organic polymers contaminated with radioactive substances, particularly with long life actinoid are heated and carbonized in concentrated sulfuric acid. Then, aqueous 30% H 2 O 2 solution is continuously added dropwise as an oxidizing agent till the solution turns colourless. If the carbonization was insufficient, addition of H 2 O 2 solution is stopped temporarily and the carbonization is conducted again. Thus, the organic polymers are completely decomposed by the wet oxidization. Then, the volume of the organic materials to be discharged is decreased and the radioactive substances contained are simultaneously concentrated and collected. (Seki, T.)

Aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil: a review.

Science.gov (United States)

Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

2013-11-10

Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research.

Aliphatic, Cyclic, and Aromatic Organic Acids, Vitamins, and Carbohydrates in Soil: A Review

Directory of Open Access Journals (Sweden)

Valerie Vranova

2013-01-01

Full Text Available Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research.

Aliphatic, Cyclic, and Aromatic Organic Acids, Vitamins, and Carbohydrates in Soil: A Review

Science.gov (United States)

Vranova, Valerie; Rejsek, Klement; Formanek, Pavel

2013-01-01

Organic acids, vitamins, and carbohydrates represent important organic compounds in soil. Aliphatic, cyclic, and aromatic organic acids play important roles in rhizosphere ecology, pedogenesis, food-web interactions, and decontamination of sites polluted by heavy metals and organic pollutants. Carbohydrates in soils can be used to estimate changes of soil organic matter due to management practices, whereas vitamins may play an important role in soil biological and biochemical processes. The aim of this work is to review current knowledge on aliphatic, cyclic, and aromatic organic acids, vitamins, and carbohydrates in soil and to identify directions for future research. Assessments of organic acids (aliphatic, cyclic, and aromatic) and carbohydrates, including their behaviour, have been reported in many works. However, knowledge on the occurrence and behaviour of D-enantiomers of organic acids, which may be abundant in soil, is currently lacking. Also, identification of the impact and mechanisms of environmental factors, such as soil water content, on carbohydrate status within soil organic matter remains to be determined. Finally, the occurrence of vitamins in soil and their role in biological and biochemical soil processes represent an important direction for future research. PMID:24319374

Formic and Acetic Acid Observations over Colorado by Chemical Ionization Mass Spectrometry and Organic Acids' Role in Air Quality

Science.gov (United States)

Treadaway, V.; O'Sullivan, D. W.; Heikes, B.; Silwal, I.; McNeill, A.

2015-12-01

Formic acid (HFo) and acetic acid (HAc) have both natural and anthropogenic sources and a role in the atmospheric processing of carbon. These organic acids also have an increasing importance in setting the acidity of rain and snow as precipitation nitrate and sulfate concentrations have decreased. Primary emissions for both organic acids include biomass burning, agriculture, and motor vehicle emissions. Secondary production is also a substantial source for both acids especially from biogenic precursors, secondary organic aerosols (SOAs), and photochemical production from volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs). Chemical transport models underestimate organic acid concentrations and recent research has sought to develop additional production mechanisms. Here we report HFo and HAc measurements during two campaigns over Colorado using the peroxide chemical ionization mass spectrometer (PCIMS). Iodide clusters of both HFo and HAc were recorded at mass-to-charge ratios of 173 and 187, respectively. The PCIMS was flown aboard the NCAR Gulfstream-V platform during the Deep Convective Clouds and Chemistry Experiment (DC3) and aboard the NCAR C-130 during the Front Range Air Pollution and Photochemistry Experiment (FRAPPE). The DC3 observations were made in May and June 2012 extending from the surface to 13 km over the central and eastern United States. FRAPPE observations were made in July and August 2014 from the surface to 7 km over Colorado. DC3 measurements reported here are focused over the Colorado Front Range and complement the FRAPPE observations. DC3 HFo altitude profiles are characterized by a decrease up to 6 km followed by an increase either back to boundary layer mixing ratio values or higher (a "C" shape). Organic acid measurements from both campaigns are interpreted with an emphasis on emission sources (both natural and anthropogenic) over Colorado and in situ photochemical production especially ozone precursors.

Effect of fermentation period on the organic acid and amino acid contents of Ogiri from castor oil bean seeds

Directory of Open Access Journals (Sweden)

Ojinnaka, M-T. C.

2013-01-01

Full Text Available Aims: To monitor the changes in the concentration of organic acid and amino acid contents during the fermentation of castor oil bean seed into ogiri.Methodology and results: In this study, ogiri, a Nigerian fermented food condiment was prepared from castor oil bean using Bacillus subtilis as a monoculture starter for the production of three different fermented castor oil bean condiment samples: B1 (0% NaCl/lime, B2 (2% NaCl, B3 (3% lime. Variations in the composition of the castor oil bean with fermentation over 96 h periods were evaluated for organic acid and amino acid contents using High Performance Liquid Chromatography. Organic acids were detected in the fermented castor oil bean samples as fermentation period increased to 96 h. Organic acids identified were oxalic, citric, tartaric, malic, succinic, lactic, formic, acetic, propionic and butyric acids. The lactic acid contents in sample B1 (0% NaCl/lime decreased initially and then increased as the fermentation period progressed. The value at 96 h fermentation was 1.336 µg/mL as against 0.775 µg/mL at 0 h fermentation. Sample B3 (3% lime had lactic acid content that increased as fermentation period increased with lactic acid content of 1.298 µg/mL at 96 h fermentation. The acetic acid content of sample B1 increased as fermentation progressed and at 96 h fermentation, its value was 1.204 µg/mL while those of B2 and B3 were 0.677 µg/mL and 1.401 µg/mL respectively. The three fermented castor oil bean samples also contained sufficient amount of amino acids. Sample B1 had the highest values in isoleucine glycine and histidine with values 1.382 µg/mL, 0.814 µg/mL and 1.022 µg/mL respectively while sample B2 had the highest value in leucine content with 0.915 µg/mL at 96 h fermentation, closely followed by sample B3 and B1 with 0.798 µg/mL and 0.205 µg/mL respectively. The results of amino acid analysis indicated a high concentration of all amino acids at 96 h of fermentation

Prostate hypofractionated radiation therapy with injection of hyaluronic acid: acute toxicities in a phase 2 study.

Science.gov (United States)

Chapet, Olivier; Decullier, Evelyne; Bin, Sylvie; Faix, Antoine; Ruffion, Alain; Jalade, Patrice; Fenoglietto, Pascal; Udrescu, Corina; Enachescu, Ciprian; Azria, David

2015-03-15

Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity. Copyright © 2015 Elsevier Inc. All rights reserved.

Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

International Nuclear Information System (INIS)

Chapet, Olivier; Decullier, Evelyne; Bin, Sylvie; Faix, Antoine; Ruffion, Alain; Jalade, Patrice; Fenoglietto, Pascal; Udrescu, Corina; Enachescu, Ciprian; Azria, David

2015-01-01

Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity

Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

Energy Technology Data Exchange (ETDEWEB)

Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); EMR3738, Université Lyon 1, Lyon (France); Decullier, Evelyne; Bin, Sylvie [Pole Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon (France); Université Lyon 1, Lyon (France); EA SIS, Université de Lyon, Lyon (France); Faix, Antoine [Department of Urology, Clinique Beausoleil, Montpellier (France); Ruffion, Alain [Université Lyon 1, Lyon (France); Department of Urology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Jalade, Patrice [Department of Medical Physics, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Fenoglietto, Pascal [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France); Udrescu, Corina; Enachescu, Ciprian [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Azria, David [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France)

2015-03-15

Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity.

Toxicity of strontium-90 depending on the way of its administration to animal organisms

International Nuclear Information System (INIS)

Shvedov, V.L.

1978-01-01

Toxicity of strontium-90 administered orally is almost thrice lower than that after parenteral administration. The values of the doses absorbed in the critical organ of rats, corresponding to LDsub(50/30), were 2400 to 2600 rad irrespective of the route of the radionuclide administration

Bilateral retrobulbar optic neuropathy as the only sign of zoledronic acid toxicity.

Science.gov (United States)

Lavado, Félix Manco; Prieto, Marta Para; Osorio, María Rosalba Ramoa; Gálvez, María Isabel López; Leal, Lucía Manzanas

2017-10-01

Bisphosphonates may rarely cause ocular adverse effects and retrobulbar optic neuropathy (RON) secondary to zoledronic acid is very rare. A 67-year-old man was referred because of progressive and painless decrease vision in the left eye. He had been treated with 7 cycles of zoledronic acid infusions because of metastatic prostate cancer. On examination, VA was 20/20 in the right eye (OD) and 20/50 in the left eye (OS). The optic nerve was unremarkable OU. Pattern visual evoked potentials (pVEP) and electroretinography were performed with the result of VEP responses abolished in OS, and the VEP waveform within the normal range amplitude and delayed peak latencies in OD. Due to the high suspicion of bilateral RON secondary to zoledronic acid, we decided to discontinue the treatment. Two months later, VA was 20/20 OD and hand motions OS, with relative afferent pupillary defect and a pallor of the optic disc in OS. The diagnosis of bilateral RON secondary to zoledronic acid infusions was confirmed, and it was only partially reversible. Zoledronic acid is a potent new generation bisphosphonate increasingly used in oncologic patients and it is usually well tolerated. Optic nerve toxicity is not a side effect recognised by either the Food and Drug Administration or the drug manufacturers, and to our knowledge, this is the first case of zoledronic acid-related bilateral RON with late onset. In conclusion, patients treated with bisphosphonates should be informed about the possibility of ocular side-effects, and ophthalmologists should be consider discontinuing the drug. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative toxicity test of water-accommodated fractions of oils and oil dispersants to marine organisms

International Nuclear Information System (INIS)

1989-01-01

This reference method describes a simple procedure for comparing the toxicity of oil, oil dispersants, and mixtures thereof, to marine animals. It allows the toxicity of different dispersants to be rapidly compared to that of oil, or of a mixture of oil an oil dispersant. It is designed for routine monitoring and screening purposes and is not appropriate as a research method. The physical and chemical properties of oil dispersants create many difficulties in the measurements of their toxicity to marine organisms. Strictly speaking, their toxicity can only be accurately estimated using complex procedures and apparatus. (A relatively simple apparatus for preparing oil/water or oil/water/oil dispersant emulsions is described in Appendix B). Simpler methods can provide useful information, provided their limitations are clearly understood and taken into consideration in the assessment and application of their results. Some of the special considerations relating to the measurement of the toxicity of oil and oil dispersants are described in Appendix A. The Appendix also explains the rationale and limitations of the method described here. 3 refs, 4 figs, 2 tabs

Effect of inorganic salts on the volatility of organic acids.

Science.gov (United States)

Häkkinen, Silja A K; McNeill, V Faye; Riipinen, Ilona

2014-12-02

Particulate phase reactions between organic and inorganic compounds may significantly alter aerosol chemical properties, for example, by suppressing particle volatility. Here, chemical processing upon drying of aerosols comprised of organic (acetic, oxalic, succinic, or citric) acid/monovalent inorganic salt mixtures was assessed by measuring the evaporation of the organic acid molecules from the mixture using a novel approach combining a chemical ionization mass spectrometer coupled with a heated flow tube inlet (TPD-CIMS) with kinetic model calculations. For reference, the volatility, i.e. saturation vapor pressure and vaporization enthalpy, of the pure succinic and oxalic acids was also determined and found to be in agreement with previous literature. Comparison between the kinetic model and experimental data suggests significant particle phase processing forming low-volatility material such as organic salts. The results were similar for both ammonium sulfate and sodium chloride mixtures, and relatively more processing was observed with low initial aerosol organic molar fractions. The magnitude of low-volatility organic material formation at an atmospherically relevant pH range indicates that the observed phenomenon is not only significant in laboratory conditions but is also of direct atmospheric relevance.

Toxicity of a dental adhesive compared with ionizing radiation and zoledronic acid.

Science.gov (United States)

Alcaraz, Miguel; Olivares, Amparo; Achel, Daniel-Giyngiri; García-Cruz, Emilio; Fondevilla-Soler, Adriana; Canteras-Jordana, Manuel

2015-07-01

To determine the toxicity of aqueous dilutions of a universal self-priming dental adhesive (DA) and comparing these with those elicited by exposure to ionizing radiation (IR), Zoledronic acid (Z) treatment and the synergic effects of the combined treatment with IR+Z. The genotoxic effect of DA was determined by the increase in the frequency of micronuclei in cytokinesis-blocked in cultured human lymphocytes before and after exposure to 2Gy of X-rays. The cytotoxic effect was studied by using the MTT cell viability test in normal prostate cell lines (PNT2) after exposure to different X-ray doses (0Gy-20Gy). The cell lines divided into different groups and treated with different test substances: DA in presence of O2, DA in absence of O2, Z-treated and control. An in vitro dose-dependent and time-dependent cytotoxic effect of DA, Z and IR on PNT2 cells (p>0.001) was demonstrated. DA without-O2, following the recommendations of manufacturers, had a more pronounced effect of increasing cell death than DA with-O2 (p<0.001). In the genotoxicity assay, DA at 25% of its original concentration significantly increased chromosome damage (p<0.001). The samples studied were found to be toxic, and the samples photo-polymerized in absence of O2 showed a bigger cytotoxic effect comparable to the additive toxic effect showed by the combined treatment of IR+Z. Additional effort should be carried out to develop adhesives, which would reduce the release of hazardous substances; since toxic effects are similar to that reported by other agents whose clinical use is controlled by the health authorities.

USING STRUCTURAL EFFECTS ON THE ORGANIZATION OF THE CYTOSKELETON OF RAINBOW TROUT HEPATOCYTES TO SORT PATHWAYS OF REACTIVE TOXICITY

Science.gov (United States)

Quinones have been shown to be more acutely toxic to aquatic organisms than chemicals that are not capable of either direct interaction with cellular nucleophiles or potentially metabolized free radicals. For the development of accurate QSAR models, in vitro toxicity assays are n...

Effect of organic acids traces on the carbon steel corrosion behavior

International Nuclear Information System (INIS)

Stefanescu, D.; Radulescu; Mogosan, S.

2009-01-01

There are many different ways in which organic matter may get in water-steam cycles. One important pathway is constituted by organic matter admitted into the system by chemical make-up water under standard operation conditions (without inverse osmosis). The high molecular weight organic matter, in particularly polysaccharides are broken in organic acids, in particular acetic and formic acid. This paper presents an overview of the investigations undertaken referring to the behavior SA106 gr. B mild steel in secondary circuit aqueous environment contaminated with formic and acetic acid traces. The samples were filmed in static autoclaves in operation conditions of secondary circuit, in contaminated environment and after that they were investigated using metallographic microscopy and SEM. In addition, an electrochemical technique videlicet impedance spectroscopy (EIS) was used to investigate the corrosion behavior of SA106 gr. B carbon steel in secondary circuit medium contaminated with formic and acetic acid traces. (authors)

Amino acids as possible alternative nitrogen source for growth of Euglena gracilis Z in life support systems.

Science.gov (United States)

Richter, P R; Liu, Y; An, Y; Li, X; Nasir, A; Strauch, S M; Becker, I; Krüger, J; Schuster, M; Ntefidou, M; Daiker, V; Haag, F W M; Aiach, A; Lebert, M

2015-01-01

In recent times Euglena gracilis Z was employed as primary producer in closed environmental life-support system (CELSS), e.g. in space research. The photosynthetic unicellular flagellate is not capable of utilizing nitrate, nitrite, and urea as nitrogen source. Therefore, ammonium is supplied as an N-source in the lab (provided as diammonium-dihydrogenphosphate, (NH4)2HPO4) to E. gracilis cultures. While nitrate exerts low toxicity to organisms, ammonium is harmful for many aquatic organisms especially, at high pH-values, which causes the ionic NH4+ (low toxicity) to be partially transformed into the highly toxic ammonia, NH3. In earlier reports, Euglena gracilis was described to grow with various amino acids as sole N-source. Our aim was to investigate alternatives for (NH4)2HPO4 as N-source with lower toxicity for organisms co-cultivated with Euglena in a CELSS. The growth kinetics of Euglena gracilis cultures was determined in the presence of different amino acids (glycine, glutamine, glutamic acid, leucine, and threonine). In addition, uptake of those amino acids by the cells was measured. Cell growth in the presence of glycine and glutamine was quite comparable to the growth in (NH4)2HPO4 containing cultures while a delay in growth was observed in the presence of leucine and threonine. Unlike, aforementioned amino acids glutamate consumption was very poor. Cell density and glutamate concentration were almost unaltered throughout the experiment and the culture reached the stationary phase within 8 days. The data are compared with earlier studies in which utilization of amino acids in Euglena gracilis was investigated. All tested amino acids (glutamate with limitations) were found to have the potential of being an alternative N-source for Euglena gracilis. Hence, these amino acids can be used as a non-toxic surrogate for (NH4)2HPO4. Copyright © 2014 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

Organic acid production from starchy waste by rumen derived microbial communities

OpenAIRE

Ayudthaya, S. P. N.; Van De Weijer, Antonius H. P.; Van Gelder, Antonie H.; Stams, Alfons Johannes Maria; De Vos, Willem M.; Plugge, Caroline M.

2017-01-01

Microbiology Centennial Symposium 2017 - Exploring Microbes for the Quality of Life (Book of Abstracts) Converting organic waste to energy carriers and valuable products such as organic acids (OA) using microbial fermentation is one of the sustainable options of renewable energy. Substrate and inoculum are important factors in optimizing the fermentation. In this study, we investigated organic acid production and microbial composition shift during the fermentation of starchy (p...

Maintenance of adult primate liver in organ culture: Potential use in toxicity testing

International Nuclear Information System (INIS)

Smith, P.F.; O'Brien, K.A.; Allen, L.; DeLuca, J.; Norman, B.; Keenan, K.P.

1991-01-01

Adult Rhesus monkey liver slices were incubated using a dynamic organ culture method to determine hepatocyte viability, drug biotransformation potential and the in vitro response to the hepatotoxicant, allyl alcohol (AA). After 1, 2, 4, or 8 hr, slices were removed from culture and analyzed for incorporation of [ 3 H]-leucine into acid-precipitable material, and medium alanine aminotransferase (ALT) activity was determined. Separate slices were taken for histological evaluation and for evaluation of microsomal 7-ethoxy-4-trifluoromethyl coumarin-O-deethylase (EFCOD) activity. Incorporation of [ 3 H]-leucine into slices was linear over the period of incubation and was specifically inhibited by cycloheximide (10 uM) at all time points. In the absence of AA, enzyme leakage was minimal over 8 hr. Marked ALT leakage occurred with 1 mM AA. Control slices had an initial fall to 55% of in vivo EFCOD activity that stabilized at 40-50% control slices indicated that there was minimal cellular degeneration and that, in PAS-stained sections, glycogen accumulation occurred over the incubation period. This system allows for maintenance and viability of adult primate liver slices in culture for at least 8 hr and may be useful for in vitro toxicity and biotransformation studies

Separation and recovery of organic acids from fermented kitchen ...

African Journals Online (AJOL)

PRECIOUS

2009-11-02

Nov 2, 2009 ... Figure 1 shows the recovery process of organic acids from fermen- ted kitchen waste. ... freezing process was carried out using a deep freezer at -30°C for overnight. .... few factors which affect the production of lactic acid in the.

Effects of Organic and Inorganic Nitrogen on the Growth and Production of Domoic Acid by Pseudo-nitzschia multiseries and P. australis (Bacillariophyceae) in Culture.

Science.gov (United States)

Martin-Jézéquel, Véronique; Calu, Guillaume; Candela, Leo; Amzil, Zouher; Jauffrais, Thierry; Séchet, Véronique; Weigel, Pierre

2015-11-26

Over the last century, human activities have altered the global nitrogen cycle, and anthropogenic inputs of both inorganic and organic nitrogen species have increased around the world, causing significant changes to the functioning of aquatic ecosystems. The increasing frequency of Pseudo-nitzschia spp. in estuarine and coastal waters reinforces the need to understand better the environmental control of its growth and domoic acid (DA) production. Here, we document Pseudo-nitzschia spp. growth and toxicity on a large set of inorganic and organic nitrogen (nitrate, ammonium, urea, glutamate, glutamine, arginine and taurine). Our study focused on two species isolated from European coastal waters: P. multiseries CCL70 and P. australis PNC1. The nitrogen sources induced broad differences between the two species with respect to growth rate, biomass and cellular DA, but no specific variation could be attributed to any of the inorganic or organic nitrogen substrates. Enrichment with ammonium resulted in an enhanced growth rate and cell yield, whereas glutamate did not support the growth of P. multiseries. Arginine, glutamine and taurine enabled good growth of P. australis, but without toxin production. The highest DA content was produced when P. multiseries grew with urea and P. australis grew with glutamate. For both species, growth rate was not correlated with DA content but more toxin was produced when the nitrogen source could not sustain a high biomass. A significant negative correlation was found between cell biomass and DA content in P. australis. This study shows that Pseudo-nitzschia can readily utilize organic nitrogen in the form of amino acids, and confirms that both inorganic and organic nitrogen affect growth and DA production. Our results contribute to our understanding of the ecophysiology of Pseudo-nitzschia spp. and may help to predict toxic events in the natural environment.

Profiling of the Contents of Amino Acids, Water-Soluble Vitamins, Minerals, Sugars and Organic Acids in Turkish Hazelnut Varieties

Directory of Open Access Journals (Sweden)

Taş Neslihan Göncüoğlu

2018-09-01

Full Text Available Proximate composition, profiles of amino acids, sugars, organic acids, vitamins and minerals of fourteen Turkish hazelnut varieties harvested in 2013 and 2014 were investigated. Glutamic acid, arginine and aspartic acid were the most predominant amino acids, representing of about 50% of hazelnut protein. Individual amino acid profiles showed significant differences depending upon the harvest year (p<0.05. Concentration of sucrose was the highest followed by fructose, glucose, stachyose, raffinose and myo-inositol, respectively. Phytic acid was predominant organic acid in all varieties, followed by malic acid. Independent of the variety, hazelnuts were rich in pantothenic acid, nicotinic acid, pyridoxal, biotin, thiamine, nicotinamide. Pantothenic and nicotinic acid were significantly higher in most of the varieties in harvest year 2014. Potassium was the most predominant mineral, followed by magnesium, calcium, sodium, manganese, zinc, iron and copper, respectively.

Production of organic acids in an immobilized cell reactor using ...

African Journals Online (AJOL)

Immobilized cell reactor (ICR) was developed as a novel bioreactor to convert hydrolyzed sugars to organic acids. Sugar fermentation by Propionibacterium acid-propionici entraped by calcium alginate was carried out in continuous mode to produce propionic and acetic acids. In continuous fermentation, more than 90 ...

Concentration and fractionation of hydrophobic organic acid constituents from natural waters by liquid chromatography

Science.gov (United States)

Thurman, E.M.; Malcolm, R.L.

1979-01-01

A scheme is presented which used adsorption chromatography with pH gradient elution and size-exclusion chromatography to concentrate and separate hydrophobic organic acids from water. A review of chromatographic processes involved in the flow scheme is also presented. Organic analytes which appear in each aqueous fraction are quantified by dissolved organic carbon analysis. Hydrophobic organic acids in a water sample are concentrated on a porous acrylic resin. These acids usually constitute approximately 30-50 percent of the dissolved organic carbon in an unpolluted water sample and are eluted with an aqueous eluent (dilute base). The concentrate is then passed through a column of polyacryloylmorpholine gel, which separates the acids into high- and low-molecular-weight fractions. The high- and low-molecular-weight eluates are reconcentrated by adsorption chromatography, then are eluted with a pH gradient into strong acids (predominately carboxylic acids) and weak acids (predominately phenolic compounds). For standard compounds and samples of unpolluted waters, the scheme fractionates humic substances into strong and weak acid fractions that are separated from the low molecular weight acids. A new method utilizing conductivity is also presented to estimate the acidic components in the methanol fraction.

Hepatic Toxicity of Perfluorocarboxylic Acids.

Science.gov (United States)

1996-07-01

1995). 3. N. V. Reo, C. M. Goecke, L. Narayanan, and B. M. Jarnot. "Effects of Perfluoro-n-octanoic Acid , Perfluoro-n-decanoic Acid , and Clofibrate ...Artz, and B. M. Jarnot: "ILiver Phosphorous Metabolic Response to Perfluorocarboxylic Acids and Clofibrate in Rats and Guinea Pigs: A 31 P NMR Study...Peroxisome Induction by Perfluoro-n-decanoic Acid and Clofibrate in the Rat: Proliferation Versus Activity." International Society for the Study of

Removal of organic matter and toxicity in hospital wastewaters by ozone

International Nuclear Information System (INIS)

Grisales Penagos, Dayana; Ortega Lopez, Joela; Rodriguez Chaparro, Tatiana

2012-01-01

Hospital wastewaters are considered to be one of the major sources of emergent contaminants as result of the dairy activities and excretion of the patients. Several studies have demonstrated that these compounds are not easily removed in conventional wastewater treatments that use biological process. This study evaluated the removal of the organic matter present in real hospital effluent applying ozone at different pH conditions (3,0, 6,7, 10). Parameters such as UV254, biodegradability ratio (COD/BOD) and color (VIS436) were measured. Moreover, it was assessed the acute toxicity with Allium cepa L. The results demonstrated that with an ozone dosage of 187 mgO3/h and pH = 10 the biodegradability increased by 70% and the acute toxicity decreased by 62%, whereas for pH =3,0 both UV254 and color removal was notable. The ozone application seems to be a viable alternative to treat hospital effluents as a pretreatment of a biological process.

Removal of organic matter and toxicity in hospital wastewaters by ozone

International Nuclear Information System (INIS)

Grisales Penagos Dayana; Ortega Lopez Joela; Rodriguez Chaparro Tatiana

2012-01-01

Hospital wastewaters are considered to be one of the major sources of emergent contaminants as result of the dairy activities and excretion of the patients. Several studies have demonstrated that these compounds are not easily removed in conventional wastewater treatments that use biological process. This study evaluated the removal of the organic matter present in real hospital effluent applying ozone at different pH conditions (3,0, 6,7, 10). Parameters such as UV254, biodegradability ratio (COD/BOD) and color (VIS436) were measured. Moreover, it was assessed the acute toxicity with Allium cepa L. The results demonstrated that with an ozone dosage of 187 MgO 3 /h and pH = 10 the biodegradability increased by 70% and the acute toxicity decreased by 62%, whereas for pH =3,0 both UV254 and color removal was notable. The ozone application seems to be a viable alternative to treat hospital effluents as a pretreatment of a biological process. Allium cepa L., biodegradability, emergent compounds, recalcitrance

Nature and prevalence of non-additive toxic effects in industrially relevant mixtures of organic chemicals.

Science.gov (United States)

Parvez, Shahid; Venkataraman, Chandra; Mukherji, Suparna

2009-06-01

The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose-response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2(n) factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components.

Acid-base properties of Baltic Sea dissolved organic matter

Science.gov (United States)

Hammer, Karoline; Schneider, Bernd; Kuliński, Karol; Schulz-Bull, Detlef E.

2017-09-01

Calculations related to the marine CO2 system that are based on alkalinity data may be strongly biased if the contributions of organic compounds are ignored. In coastal seas, concentrations of dissolved organic matter (DOM) are frequently high and alkalinity from inorganic compounds is low. In this study, based on measurements of total alkalinity, total CO2, and pH, we determined the organic alkalinity, Aorg, in water from the central Baltic Sea. The maximum Aorg measured in the surface mixed layer during the spring bloom was > 50 μmol/kg-SW but the Aorg decreased with depth and approached zero below the permanent halocline. This behavior could be attributed to the decreased pH of deeper water layers. The data were used to calculate the bulk dissociation constant, KDOM, for marine DOM and the fraction f of dissolved organic carbon (DOC) that acts as a carrier for acid-base functional groups. The p KDOM (7.27) agreed well with the value (7.34) previously estimated in a preliminary study of organic alkalinity in the Baltic Sea. The fraction of carbon atoms carrying acid-base groups was 17% and was somewhat higher than previously reported (12%). Spike experiments performed using artificial seawater and three different humic/fulvic substances tested whether the acid-base properties of these substances explain the results of our field study. Specifically, Aorg was determined at different concentrations (DOC) of the added humic/fulvic substances. The relationship between Aorg and the DOC concentrations indicated that humic/fulvic substances are more acidic (p KDOM < 6.5) than the bulk DOC natural occurring in the Baltic Sea.

Chiral metal-organic frameworks bearing free carboxylic acids for organocatalyst encapsulation.

Science.gov (United States)

Liu, Yan; Xi, Xiaobing; Ye, Chengcheng; Gong, Tengfei; Yang, Zhiwei; Cui, Yong

2014-12-08

Two chiral carboxylic acid functionalized micro- and mesoporous metal-organic frameworks (MOFs) are constructed by the stepwise assembly of triple-stranded heptametallic helicates with six carboxylic acid groups. The mesoporous MOF with permanent porosity functions as a host for encapsulation of an enantiopure organic amine catalyst by combining carboxylic acids and chiral amines in situ through acid-base interactions. The organocatalyst-loaded framework is shown to be an efficient and recyclable heterogeneous catalyst for the asymmetric direct aldol reactions with significantly enhanced stereoselectivity in relative to the homogeneous organocatalyst. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

fractionation of lead-acid battery soil amended with biochar 36

African Journals Online (AJOL)

USER

Biochar has a high surface area, highly porous, variable – charge organic material that has the potential to ... Keywords: Biochar, Lead–acid Battery, Fractionation and Heavy metals. INTRODUCTION .... toxicity of heavy metal ions in the soils.

The Study and Development of Metal Oxide Reactive Adsorbents for the Destruction of Toxic Organic Compounds

National Research Council Canada - National Science Library

Mitchell, Mark B

2008-01-01

... and other toxic organic compounds. The research program that was developed built upon earlier results achieved in the room temperature oxidative decomposition of a chemical warfare agent simulant, dimethyl methylphosphonate (DMMP...

Treatment of Acute Tacrolimus Toxicity with Phenytoin in Solid Organ Transplant Recipients

Directory of Open Access Journals (Sweden)

Arin S. Jantz

2013-01-01

Full Text Available The pharmacokinetics of tacrolimus are influenced by many factors, including genetic variability, acute infections, liver dysfunction, and interacting medications, which can result in elevated concentrations. The most appropriate management of acute tacrolimus toxicity has not been defined though case reports exist describing the therapeutic use of enzyme inducers to increase tacrolimus metabolism and decrease concentrations. We are reporting on the utilization of phenytoin to assist in decreasing tacrolimus concentrations in a case series of four solid organ transplant recipients with acute, symptomatic tacrolimus toxicity presenting with elevated serum creatinine, potassium, and tacrolimus trough concentrations greater than 30 ng/mL. All four patients had the potential causative agents stopped or temporarily held and were given 300 to 400 mg/day of phenytoin for two to three days. Within three days of beginning phenytoin, all four patients had a decrease in tacrolimus concentration to less than 15 ng/mL, a return to or near baseline creatinine concentration, and lack of phenytoin-related side effects. Therefore, phenytoin appears to be a safe and potentially beneficial treatment option in patients with symptomatic tacrolimus toxicity.

Toxicity of proton-metal mixtures in the field: Linking stream macroinvertebrate species diversity to chemical speciation and bioavailability

Energy Technology Data Exchange (ETDEWEB)

Stockdale, Anthony [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Tipping, Edward, E-mail: et@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Lofts, Stephen [Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP (United Kingdom); Ormerod, Stephen J. [Catchment Research Group, Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3US (United Kingdom); Clements, William H. [Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO 80523 (United States); Blust, Ronny [Ecophysiology, Biochemistry and Toxicology Group, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

2010-10-01

Understanding metal and proton toxicity under field conditions requires consideration of the complex nature of chemicals in mixtures. Here, we demonstrate a novel method that relates streamwater concentrations of cationic metallic species and protons to a field ecological index of biodiversity. The model WHAM-F{sub TOX} postulates that cation binding sites of aquatic macroinvertebrates can be represented by the functional groups of natural organic matter (humic acid), as described by the Windermere Humic Aqueous Model (WHAM6), and supporting field evidence is presented. We define a toxicity function (F{sub TOX}) by summing the products: (amount of invertebrate-bound cation) x (cation-specific toxicity coefficient, {alpha}{sub i}). Species richness data for Ephemeroptera, Plecoptera and Trichoptera (EPT), are then described with a lower threshold of F{sub TOX}, below which all organisms are present and toxic effects are absent, and an upper threshold above which organisms are absent. Between the thresholds the number of species declines linearly with F{sub TOX}. We parameterised the model with chemistry and EPT data for low-order streamwaters affected by acid deposition and/or abandoned mines, representing a total of 412 sites across three continents. The fitting made use of quantile regression, to take into account reduced species richness caused by (unknown) factors other than cation toxicity. Parameters were derived for the four most common or abundant cations, with values of {alpha}{sub i} following the sequence (increasing toxicity) H{sup +} < Al < Zn < Cu. For waters affected mainly by H{sup +} and Al, F{sub TOX} shows a steady decline with increasing pH, crossing the lower threshold near to pH 7. Competition effects among cations mean that toxicity due to Cu and Zn is rare at lower pH values, and occurs mostly between pH 6 and 8.

Nitric-phosphoric acid oxidation of organic waste materials

International Nuclear Information System (INIS)

Pierce, R.A.; Smith, J.R.

1995-01-01

A wet chemical oxidation technology has been developed to address issues facing defense-related facilities, private industry, and small-volume generators such as university and medical laboratories. Initially tested to destroy and decontaminate a heterogenous mixture of radioactive-contaminated solid waste, the technology can also remediate other hazardous waste forms. The process, unique to Savannah River, offers a valuable alternative to incineration and other high-temperature or high-pressure oxidation processes. The process uses nitric acid in phosphoric acid; phosphoric acid allows nitric acid to be retained in solution well above its normal boiling point. The reaction converts organics to carbon dioxide and water, and generates NO x vapors which can be recycled using air and water. Oxidation is complete in one to three hours. In previous studies, many organic compounds were completely oxidized, within experimental error, at atmospheric pressure below 180 degrees C; more stable compounds were decomposed at 200 degrees C and 170 kPa. Recent studies have evaluated processing parameters and potential throughputs for three primary compounds: EDTA, polyethylene, and cellulose. The study of polyvinylchloride oxidation is incomplete at this time

Algal toxicity of the alternative disinfectants performic acid (PFA), peracetic acid (PAA), chlorine dioxide (ClO2) and their by-products hydrogen peroxide (H2O2) and chlorite (ClO2-)

DEFF Research Database (Denmark)

Chhetri, Ravi Kumar; Baun, Anders; Andersen, Henrik Rasmus

2017-01-01

Environmental effect evaluation of disinfection of combined sewer overflow events with alternative chemical disinfectants requires that the environmental toxicity of the disinfectants and the main by-products of their use are known. Many disinfectants degrade quickly in water which should......: performic acid (PFA), peracetic acid (PAA) and chlorine dioxide (ClO2) as well as two by-products of their use: hydrogen peroxide (H2O2) and chlorite. All of the five chemicals investigated showed clear toxicity to the algae with well-defined dose response curves. The EC50 values ranged from 0.16 to 2.9 mg...

Repeated subcutaneous administrations of krokodil causes skin necrosis and internal organs toxicity in Wistar rats: putative human implications.

Science.gov (United States)

Alves, Emanuele Amorim; Brandão, Pedro; Neves, João Filipe; Cravo, Sara Manuela; Soares, José Xavier; Grund, Jean-Paul C; Duarte, José Alberto; Afonso, Carlos M M; Pereira Netto, Annibal Duarte; Carvalho, Félix; Dinis-Oliveira, Ricardo Jorge

2017-05-01

"Krokodil" is the street name for an impure homemade drug mixture used as a cheap substitute for heroin, containing desomorphine as the main opioid. Abscesses, gangrene, thrombophlebitis, limb ulceration and amputations, jaw osteonecrosis, skin discoloration, ulcers, skin infections, and bleeding are some of the typical reported signs in humans. This study aimed to understand the toxicity of krokodil using Wistar male rats as experimental model. Animals were divided into seven groups and exposed subcutaneously to NaCl 0.9% (control), krokodil mixture free of psychotropic substances (blank krokodil), pharmaceutical grade desomorphine 1 mg/kg, and four different concentrations of krokodil (containing 0.125, 0.25, 0.5, and 1 mg/kg of desomorphine) synthesized accordingly to a "domestic" protocol followed by people who inject krokodil (PWIK). Daily injections for five consecutive days were performed, and animals were sacrificed 24 hr after the last administration. Biochemical and histological analysis were carried out. It was shown that the continuous use of krokodil may cause injury at the injection area, with formation of necrotic zones. The biochemical results evidenced alterations on cardiac and renal biomarkers of toxicity, namely, creatine kinase, creatine kinase-MB, and uric acid. Significant alteration in levels of reduced and oxidized glutathione on kidney and heart suggested that oxidative stress may be involved in krokodil-mediated toxicity. Cardiac congestion was the most relevant finding of continuous krokodil administration. These findings contribute notably to comprehension of the local and systemic toxicological impact of this complex drug mixture on major organs and will hopefully be useful for the development of appropriate treatment strategies towards the human toxicological effects of krokodil. Copyright © 2017 John Wiley & Sons, Ltd.

Single- and mixture toxicity of three organic UV-filters, ethylhexyl methoxycinnamate, octocrylene, and avobenzone on Daphnia magna.

Science.gov (United States)

Park, Chang-Beom; Jang, Jiyi; Kim, Sanghun; Kim, Young Jun

2017-03-01

In freshwater environments, aquatic organisms are generally exposed to mixtures of various chemical substances. In this study, we tested the toxicity of three organic UV-filters (ethylhexyl methoxycinnamate, octocrylene, and avobenzone) to Daphnia magna in order to evaluate the combined toxicity of these substances when in they occur in a mixture. The values of effective concentrations (ECx) for each UV-filter were calculated by concentration-response curves; concentration-combinations of three different UV-filters in a mixture were determined by the fraction of components based on EC 25 values predicted by concentration addition (CA) model. The interaction between the UV-filters were also assessed by model deviation ratio (MDR) using observed and predicted toxicity values obtained from mixture-exposure tests and CA model. The results from this study indicated that observed ECx mix (e.g., EC 10mix , EC 25mix , or EC 50mix ) values obtained from mixture-exposure tests were higher than predicted ECx mix (e.g., EC 10mix , EC 25mix , or EC 50mix ) values calculated by CA model. MDR values were also less than a factor of 1.0 in a mixtures of three different UV-filters. Based on these results, we suggest for the first time a reduction of toxic effects in the mixtures of three UV-filters, caused by antagonistic action of the components. Our findings from this study will provide important information for hazard or risk assessment of organic UV-filters, when they existed together in the aquatic environment. To better understand the mixture toxicity and the interaction of components in a mixture, further studies for various combinations of mixture components are also required. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of Bile Acids and Acetaminophen Protein Adducts in Children and Adolescents with Acetaminophen Toxicity.

Directory of Open Access Journals (Sweden)

Laura James

Full Text Available Metabolomics approaches have enabled the study of new mechanisms of liver injury in experimental models of drug toxicity. Disruption of bile acid homeostasis is a known mechanism of drug induced liver injury. The relationship of individual bile acids to indicators of oxidative drug metabolism (acetaminophen protein adducts and liver injury was examined in children with acetaminophen overdose, hospitalized children with low dose exposure to acetaminophen, and children with no recent exposure to acetaminophen. Nine bile acids were quantified through targeted metabolomic analysis in the serum samples of the three groups. Bile acids were compared to serum levels of acetaminophen protein adducts and alanine aminotransferase. Glycodeoxycholic acid, taurodeoxycholic acid, and glycochenodeoxycholic acid were significantly increased in children with acetaminophen overdose compared to healthy controls. Among patients with acetaminophen overdose, bile acids were higher in subjects with acetaminophen protein adduct values > 1.0 nmol/mL and modest correlations were noted for three bile acids and acetaminophen protein adducts as follows: taurodeoxycholic acid (R=0.604; p<0.001, glycodeoxycholic acid (R=0.581; p<0.001, and glycochenodeoxycholic acid (R=0.571; p<0.001. Variability in bile acids was greater among hospitalized children receiving low doses of acetaminophen than in healthy children with no recent acetaminophen exposure. Compared to bile acids, acetaminophen protein adducts more accurately discriminated among children with acetaminophen overdose, children with low dose exposure to acetaminophen, and healthy control subjects. In children with acetaminophen overdose, elevations of conjugated bile acids were associated with specific indicators of acetaminophen metabolism and non-specific indicators of liver injury.

Diuron exposure induces systemic and organ-specific toxicity following acute and sub-chronic exposure in male Wistar rats.

Science.gov (United States)

Domingues, Alexandre; Barbisan, Luis Fernando; Martins, Priscila Raquel; Spinardi-Barbisan, Ana Lúcia Tozzi

2011-05-01

Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] is a substitute urea herbicide widely used on agricultural crops with potential mutagenic, teratogenic, reproductive and carcinogenic effects. Nonetheless, its toxic potential on the immune system needs a detailed assessment. Thus, in order to evaluate the adverse effect of this herbicide on lymphohematopoietic organs and macrophage activity, male Wistar rats were orally treated with Diuron at 125, 1250 and 2500 ppm for 14, 28 or 90 days. General signs of toxicity were observed in Diuron-treated groups (1250 and 2500 ppm), including reduced food intake and body weight gain, as well as higher relative weights for spleen, kidneys and liver (28 and 90-day toxicity studies) and elevated serum levels of ALT, albumin, total protein, creatinine and urea (28-day toxicity study). Diuron exposure caused a severe depletion of splenic white pulp compartments and cellularity, followed by a decreased number of CD4(+) T lymphocytes, increased extramedullary hematopoiesis and deposition of hemosiderin in red pulp. Despite alteration in macrophage spreading, the macrophagic activity was not significantly affected by the herbicide. Under these experimental conditions, the results suggest that Diuron exerts systemic and target-organ toxicity, mainly at higher concentration. Copyright © 2011 Elsevier B.V. All rights reserved.

Development and Preliminary Assessment of Hemoperfusion Cartridge with Tannic Acid for Toxic Proteins' Precipitation: An In Vitro Model

Directory of Open Access Journals (Sweden)

Valquíria Miwa Hanai Yoshida

2016-09-01

Full Text Available Charcoal hemoperfusion (CHP is one of the extracorporeal removal techniques that are used to remove toxins from the body. CHP generally is considered the preferred method for extracorporeal extraction of several toxins—toxins that are adsorbed by activated charcoal. Assessments of the tannic acid's protective effects on ophidian poisoning are associated with the toxic proteins' precipitation by tannic acid. The challenge in treating a snakebite lies in removing the injected poison with minimal damage to blood constituent proteins. An alternative is CHP, and this investigation proposed to develop a column for hemoperfuser cartridge, combining charcoal granules trapped between layers of polymeric material conjugated to tannic acid, using an in vitro model scaled to the Wistar rat, which can be tested in an animal model. The cartridge was evaluated using the 22 full factorial design, in duplicate, as a method to study the effects of granulated-charcoal size and tannic acid concentration on the hematologic profile (platelet and leukocyte counts and biochemical profile (total serum protein and albumin dosages of sheep blood. The results demonstrate that charcoal in hemoperfuser cartridge: (1 decreases the serum in sheep blood volume, as consequence, (2 increases the serum proteins' concentration, and (iii exerts slight influence on albumin. The inclusion of tannic acid in hemoperfuser column precipitates some of serum proteins and albumin, decreasing their concentrations in the plasma serum. In conclusion, based on these effects we can suggest the use of 0.02 g tannic acid concentration and 8–20 mesh granulated charcoal in hemoperfuser cartridge for precipitating toxic proteins from snake venoms.

Transcriptomic responses of European flounder (Platichthys flesus) to model toxicants

Energy Technology Data Exchange (ETDEWEB)

Williams, Tim D. [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)], E-mail: t.d.williams@bham.ac.uk; Diab, Amer [Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA (United Kingdom); Ortega, Fernando [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Sabine, Victoria S. [Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA (United Kingdom); Godfrey, Rita E.; Falciani, Francesco; Chipman, J. Kevin [School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); George, Stephen G. [Institute of Aquaculture, University of Stirling, Stirling, Scotland FK9 4LA (United Kingdom)

2008-11-11

The temporal transcriptomic responses in liver of Platichthys flesus to model environmental pollutants were studied over a 16-day time span after intraperitoneal injection with cadmium chloride (50 {mu}g/kg in saline), 3-methylcholanthrene (25 mg/kg in olive oil), Aroclor 1254 (50 mg/kg in olive oil), tert-butyl-hydroperoxide (5 mg/kg in saline), Lindane (25 mg/kg in olive oil), perfluoro-octanoic acid (100 mg/kg in olive oil) and their vehicles, olive oil (1 ml/kg) or saline (0.9%). Statistical, gene ontology and supervised analysis clearly demonstrated the progression from acute effects, biological responses to and recovery from the treatments. Key biological processes disturbed by the individual treatments were characterised by gene ontology analyses and individual toxicant-responsive genes and pathways were identified by supervised analyses. Responses to the polyaromatic and chlorinated aromatic compounds showed a degree of commonality but were distinguishable and they were clearly segregated from the responses to the pro-oxidants cadmium and the organic hydroperoxide, as well as from the peroxisomal proliferator, perfluoro-octanoic acid. This study demonstrated the utility of the microarray technique in the identification of toxicant-responsive genes and in discrimination between modes of toxicant action.

Transcriptomic responses of European flounder (Platichthys flesus) to model toxicants

International Nuclear Information System (INIS)

Williams, Tim D.; Diab, Amer; Ortega, Fernando; Sabine, Victoria S.; Godfrey, Rita E.; Falciani, Francesco; Chipman, J. Kevin; George, Stephen G.

2008-01-01

The temporal transcriptomic responses in liver of Platichthys flesus to model environmental pollutants were studied over a 16-day time span after intraperitoneal injection with cadmium chloride (50 μg/kg in saline), 3-methylcholanthrene (25 mg/kg in olive oil), Aroclor 1254 (50 mg/kg in olive oil), tert-butyl-hydroperoxide (5 mg/kg in saline), Lindane (25 mg/kg in olive oil), perfluoro-octanoic acid (100 mg/kg in olive oil) and their vehicles, olive oil (1 ml/kg) or saline (0.9%). Statistical, gene ontology and supervised analysis clearly demonstrated the progression from acute effects, biological responses to and recovery from the treatments. Key biological processes disturbed by the individual treatments were characterised by gene ontology analyses and individual toxicant-responsive genes and pathways were identified by supervised analyses. Responses to the polyaromatic and chlorinated aromatic compounds showed a degree of commonality but were distinguishable and they were clearly segregated from the responses to the pro-oxidants cadmium and the organic hydroperoxide, as well as from the peroxisomal proliferator, perfluoro-octanoic acid. This study demonstrated the utility of the microarray technique in the identification of toxicant-responsive genes and in discrimination between modes of toxicant action

Application of the Hard and Soft, Acids and Bases (HSAB) theory to toxicant--target interactions.

Science.gov (United States)

Lopachin, Richard M; Gavin, Terrence; Decaprio, Anthony; Barber, David S

2012-02-20

Many chemical toxicants and/or their active metabolites are electrophiles that cause cell injury by forming covalent bonds with nucleophilic targets on biological macromolecules. Covalent reactions between nucleophilic and electrophilic reagents are, however, discriminatory since there is a significant degree of selectivity associated with these interactions. Over the course of the past few decades, the theory of Hard and Soft, Acids and Bases (HSAB) has proven to be a useful tool in predicting the outcome of such reactions. This concept utilizes the inherent electronic characteristic of polarizability to define, for example, reacting electrophiles and nucleophiles as either hard or soft. These HSAB definitions have been successfully applied to chemical-induced toxicity in biological systems. Thus, according to this principle, a toxic electrophile reacts preferentially with biological targets of similar hardness or softness. The soft/hard classification of a xenobiotic electrophile has obvious utility in discerning plausible biological targets and molecular mechanisms of toxicity. The purpose of this perspective is to discuss the HSAB theory of electrophiles and nucleophiles within a toxicological framework. In principle, covalent bond formation can be described by using the properties of their outermost or frontier orbitals. Because these orbital energies for most chemicals can be calculated using quantum mechanical models, it is possible to quantify the relative softness (σ) or hardness (η) of electrophiles or nucleophiles and to subsequently convert this information into useful indices of reactivity. This atomic level information can provide insight into the design of corroborative laboratory research and thereby help investigators discern corresponding molecular sites and mechanisms of toxicant action. The use of HSAB parameters has also been instrumental in the development and identification of potential nucleophilic cytoprotectants that can scavenge toxic

APPLICATION OF THE HARD AND SOFT, ACIDS AND BASES (HSAB) THEORY TO TOXICANT-TARGET INTERACTIONS

Science.gov (United States)

LoPachin, Richard M.; Gavin, Terrence; DeCaprio, Anthony; Barber, David S.

2011-01-01

Many chemical toxicants and/or their active metabolites are electrophiles that cause cell injury by forming covalent bonds with nucleophilic targets on biological macromolecules. Covalent reactions between nucleophilic and electrophilic reagents are however discriminatory, since there is a significant degree of selectivity associated with these interactions. Over the course of the past few decades, the theory of Hard and Soft, Acid and Bases (HSAB) has proven to be a useful tool in predicting the outcome of such reactions. This concept utilizes the inherent electronic characteristic of polarizability to define, for example, reacting electrophiles and nucleophiles as either hard or soft. These HSAB definitions have been successfully applied to chemical-induced toxicity in biological systems. Thus, according to this principle, a toxic electrophile reacts preferentially with biological targets of similar hardness or softness. The soft/hard classification of a xenobiotic electrophile has obvious utility in discerning plausible biological targets and molecular mechanisms of toxicity. The purpose of this Perspective is to discuss the HSAB theory of electrophiles and nucleophiles within a toxicological framework. In principle, covalent bond formation can be described by using the properties of their outermost or frontier orbitals. Because these orbital energies for most chemicals can be calculated using quantum mechanical models, it is possible to quantify the relative softness (σ) or hardness (η) of electrophiles or nucleophiles and to subsequently convert this information into useful indices of reactivity. This atomic level information can provide insight into the design of corroborative laboratory research and thereby help investigators discern corresponding molecular sites and mechanisms of toxicant action. The use of HSAB parameters has also been instrumental in the development and identification of potential nucleophilic cytoprotectants that can scavenge toxic

Synthesis of Amino Acid Precursors with Organic Solids in Planetesimals with Liquid Water

Science.gov (United States)

Kebukawa, Y; Misawa, S.; Matsukuma, J.; Chan, Q. H. S.; Kobayashi, J.; Tachibana, S.; Zolensky, M. E.

2017-01-01

Amino acids are important ingredients of life that would have been delivered to Earth by extraterrestrial sources, e.g., comets and meteorites. Amino acids are found in aqueously altered carbonaceous chondrites in good part in the form of precursors that release amino acids after acid hydrolysis. Meanwhile, most of the organic carbon (greater than 70 weight %) in carbonaceous chondrites exists in the form of solvent insoluble organic matter (IOM) with complex macromolecular structures. Complex macromolecular organic matter can be produced by either photolysis of interstellar ices or aqueous chemistry in planetesimals. We focused on the synthesis of amino acids during aqueous alteration, and demonstrated one-pot synthesis of a complex suite of amino acids simultaneously with IOM via hydrothermal experiments simulating the aqueous processing

Toxicity of petroleum hydrocarbon distillates to soil organisms.

Science.gov (United States)

Cermak, Janet H; Stephenson, Gladys L; Birkholz, Detlef; Wang, Zhendi; Dixon, D George

2010-12-01

Canadian standards for petroleum hydrocarbons in soil are based on four distillate ranges (F1, C6-C10; F2, >C10-C16; F3, >C16-C34; and F4, >C34). Concerns have arisen that the ecological soil contact standards for F3 may be overly conservative. Oil distillates were prepared and characterized, and the toxicity of F3 and two subfractions, F3a (>C16-C23) and F3b (>C23-C34), to earthworms (Eisenia andrei), springtails (Orthonychiurus folsomi), and northern wheatgrass (Elymus lanceolatus), as well as the toxicity of F2 to earthworms, was determined. Clean soil was spiked with individual distillates and measured concentrations were determined for select tests. Results agree with previous studies with these distillates. Reported toxicities of crude and petroleum products to invertebrates were generally comparable to that of F3 and F3a. The decreasing order of toxicity was F3a > F3 > F3b with invertebrates, and F3a > F3b > F3 with plants. The toxicities of F3a and F3b were not sufficiently different to recommend regulating hydrocarbons based on these distillate ranges. The results also suggest that test durations may be insufficient for determining toxicity of higher distillate ranges, and that the selection of species and endpoints may significantly affect interpretation of toxicity test results. Copyright © 2010 SETAC.

Ashwagandha leaf derived withanone protects normal human cells against the toxicity of methoxyacetic acid, a major industrial metabolite.

Science.gov (United States)

Priyandoko, Didik; Ishii, Tetsuro; Kaul, Sunil C; Wadhwa, Renu

2011-05-04

The present day lifestyle heavily depends on industrial chemicals in the form of agriculture, cosmetics, textiles and medical products. Since the toxicity of the industrial chemicals has been a concern to human health, the need for alternative non-toxic natural products or adjuvants that serve as antidotes are in high demand. We have investigated the effects of Ayurvedic herb Ashwagandha (Withania somnifera) leaf extract on methoxyacetic acid (MAA) induced toxicity. MAA is a major metabolite of ester phthalates that are commonly used in industry as gelling, viscosity and stabilizer reagents. We report that the MAA cause premature senescence of normal human cells by mechanisms that involve ROS generation, DNA and mitochondrial damage. Withanone protects cells from MAA-induced toxicity by suppressing the ROS levels, DNA and mitochondrial damage, and induction of cell defense signaling pathways including Nrf2 and proteasomal degradation. These findings warrant further basic and clinical studies that may promote the use of withanone as a health adjuvant in a variety of consumer products where the toxicity has been a concern because of the use of ester phthalates.

Ashwagandha leaf derived withanone protects normal human cells against the toxicity of methoxyacetic acid, a major industrial metabolite.

Directory of Open Access Journals (Sweden)

Didik Priyandoko

Full Text Available The present day lifestyle heavily depends on industrial chemicals in the form of agriculture, cosmetics, textiles and medical products. Since the toxicity of the industrial chemicals has been a concern to human health, the need for alternative non-toxic natural products or adjuvants that serve as antidotes are in high demand. We have investigated the effects of Ayurvedic herb Ashwagandha (Withania somnifera leaf extract on methoxyacetic acid (MAA induced toxicity. MAA is a major metabolite of ester phthalates that are commonly used in industry as gelling, viscosity and stabilizer reagents. We report that the MAA cause premature senescence of normal human cells by mechanisms that involve ROS generation, DNA and mitochondrial damage. Withanone protects cells from MAA-induced toxicity by suppressing the ROS levels, DNA and mitochondrial damage, and induction of cell defense signaling pathways including Nrf2 and proteasomal degradation. These findings warrant further basic and clinical studies that may promote the use of withanone as a health adjuvant in a variety of consumer products where the toxicity has been a concern because of the use of ester phthalates.

Membrane alterations following toxic chemical insult. Research progress report No. 3 (Final), 15 July 1984-31 January 1988

Energy Technology Data Exchange (ETDEWEB)

Liss, A.

1988-03-10

A procaryotic cell system was developed that can be used to determine the toxic action of chemicals acting at the level of the eucaryotic or procaryotic cytoplasmic membrane. Cell wall-less microbes known as mycoplasmas were used. In this current study, two perfluorinated fatty acids (CB and C10) were found to inhibit the growth of the test mycoplasmas. Two apparent activities, cytotoxicity and cytolysis, were observed. At high concentrations (>10 mM), a detergent-like action was noted. At low concentrations (<10 mM), cell death was observed without detectable cell lysis. Altering the cell membrane (the presumed target of the toxic compounds) resulted in altered levels to toxicity. Similar results were obtained when human or murine B-cells were used as the target organism. The toxic action of the perfluorinated fatty acids apparently involves some interaction with the membrane of the cells being treated.

Fructose decomposition kinetics in organic acids-enriched high temperature liquid water

Energy Technology Data Exchange (ETDEWEB)

Li, Yinghua; Lu, Xiuyang; Yuan, Lei; Liu, Xin [Department of Chemical and Biochemical Engineering, Zhejiang University, Zheda Road 38, Hangzhou 310027, Zhejiang (China)

2009-09-15

Biomass continues to be an important candidate as a renewable resource for energy, chemicals, and feedstock. Decomposition of biomass in high temperature liquid water is a promising technique for producing industrially important chemicals such as 5-hydroxymethylfurfural (5-HMF), furfural, levulinic acid with high efficiency. Hexose, which is the hydrolysis product of cellulose, will be one of the most important starting chemicals in the coming society that is highly dependent on biomass. Taking fructose as a model compound, its decomposition kinetics in organic acids-enriched high temperature liquid water was studied in the temperature range from 180 C to 220 C under the pressure of 10 MPa to further improve reaction rate and selectivity of the decomposition reactions. The results showed that the reaction rate is greatly enhanced with the addition of organic acids, especially formic acid. The effects of temperature, residence time, organic acids and their concentrations on the conversion of fructose and yield of 5-HMF were investigated. The evaluated apparent activation energies of fructose decomposition are 126.8 {+-} 3.3 kJ mol{sup -1} without any catalyst, 112.0 {+-} 13.7 kJ mol{sup -1} catalyzed with formic acid, and 125.6 {+-} 3.8 kJ mol{sup -1} catalyzed with acetic acid, respectively, which shows no significant difference. (author)

Severe Toxic Skin Reaction Caused by a Common Anemone and Identification of the Culprit Organism.

Science.gov (United States)

Tezcan, Özgür Deniz; Gözer, Özgür

2015-01-01

In a marine envenomation, identification of the culprit organism can be difficult. In this case report, we present our method to identify snakelocks anemone (Anemonia viridis or formerly Anemonia sulcata) as the culprit of a severe toxic skin reaction. A. viridis is one of the most common anemones of the Mediterranean Sea and the North Atlantic Ocean. It lives at a depth of up to 10 m. It is a member of the phylum Cnidaria, which includes jellyfish, anemones, hydroids, and corals. They have toxic organelles called cnidocysts that have the capacity to inject venom with microscopic harpoon-like structures. The cnidocysts of A. viridis may cause toxic and allergic reactions, and although its venom is one of the most studied cnidarian venoms, detailed case reports are rare. © 2015 International Society of Travel Medicine.

Resilience of small intestinal beneficial bacteria to the toxicity of soybean oil fatty acids

Science.gov (United States)

Di Rienzi, Sara C; Jacobson, Juliet; Kennedy, Elizabeth A; Bell, Mary E; Shi, Qiaojuan; Waters, Jillian L; Lawrence, Peter; Brenna, J Thomas; Britton, Robert A; Walter, Jens

2018-01-01

Over the past century, soybean oil (SBO) consumption in the United States increased dramatically. The main SBO fatty acid, linoleic acid (18:2), inhibits in vitro the growth of lactobacilli, beneficial members of the small intestinal microbiota. Human-associated lactobacilli have declined in prevalence in Western microbiomes, but how dietary changes may have impacted their ecology is unclear. Here, we compared the in vitro and in vivo effects of 18:2 on Lactobacillus reuteri and L. johnsonii. Directed evolution in vitro in both species led to strong 18:2 resistance with mutations in genes for lipid biosynthesis, acid stress, and the cell membrane or wall. Small-intestinal Lactobacillus populations in mice were unaffected by chronic and acute 18:2 exposure, yet harbored both 18:2- sensitive and resistant strains. This work shows that extant small intestinal lactobacilli are protected from toxic dietary components via the gut environment as well as their own capacity to evolve resistance. PMID:29580380

Preparation of High-purity Indium Oxalate Salt from Indium Scrap by Organic Acids

International Nuclear Information System (INIS)

Koo, Su-Jin; Ju, Chang-Sik

2013-01-01

Effect of organic acid on the preparation of indium-oxalate salt from indium scraps generated from ITO glass manufacturing process was studied. Effects of parameters, such as type and concentration of organic acids, pH of reactant, temperature, reaction time on indium-oxalate salt preparation were examined. The impurity removal efficiency was similar for both oxalic acid and citric acid, but citric acid did not make organic acid salt with indium. The optimum conditions were 1.5 M oxalic acid, pH 7, 80 .deg. C, and 6 hours. On the other hand, the recoveries increased with pH, but the purity decreased. The indium-oxalate salt purity prepared by two cycles was 99.995% (4N5). The indium-oxalate salt could be converted to indium oxide and indium metal by substitution reaction and calcination

The Effect of Boric Acid and Borax on Oxidative Stress, Inflammation, ER Stress and Apoptosis in Cisplatin Toxication and Nephrotoxicity Developing as a Result of Toxication.

Science.gov (United States)

Hazman, Ömer; Bozkurt, Mehmet Fatih; Fidan, Abdurrahman Fatih; Uysal, Fadime Erkan; Çelik, Sefa

2018-03-02

The development of treatment protocols that can reduce side effects in chemotherapy applications is extremely important in terms of cancer treatment. In this context, it was aimed to investigate the effects of boric acid and borax on cisplatin toxicity (nephrotoxicity) in rats. In the experimental phase, eight groups were formed from rats. Boric acid and borax were given to the treatment groups with three different doses using gavage. On the fifth day of the study, cisplatin (10 mg/kg) was administered to all rats except the control group. At the end of the study, oxidative stress-related (GSH, MDA, PCO, GPx, 8-OHdG), inflammation-related (TNF-α, IL-1β, IL-18, MCP-1, ICAM, TGF-β), apoptosis-related (p53, caspase 1, 3, 8, 12, bcl-2, bcl-xL, NFkB), and ER stress-related (GRP78, ATF-6, PERK) basic parameters were analyzed in serum, erythrocyte, and kidney tissues. Kidney tissues were also examined by histopathological and immunohistochemical methods. Borax and boric acid at different doses decreased inflammation and oxidative stress caused by cisplatin toxicity and increased ER stress. As a result of the treatments applied to experimental animals, it was determined that boric acid and borax reduced apoptotic damage in kidney tissue, but the decrease was statistically significant only in 200 mg/kg boric acid-administered group. In the study, low anti-apoptotic effects of borate doses with the anti-inflammatory and antioxidant effect may be due to increased ER stress at the relevant doses. Further studies on the effects of boron compounds on ER stress and apoptotic mechanisms may clarify this issue. Thus, possible side effects or if there are new usage areas of borone compounds which have many usage areas in clinics can be detected.

Weak organic acid stress in Bacillus subtilis

NARCIS (Netherlands)

ter Beek, A.S.

2009-01-01

Weak organic acids are commonly used food preservatives that protect food products from bacterial contamination. A variety of spore-forming bacterial species pose a serious problem to the food industry by causing extensive food spoilage or even food poisoning. Understanding the mechanisms of

Inorganic nanomaterials in the aquatic environment: behavior, toxicity, and interaction with environmental elements

Directory of Open Access Journals (Sweden)

Krzyżewska Iwona

2016-03-01

Full Text Available The aim of this paper is to present characteristics, toxicity and environmental behavior of nanoparticles (NPs (silver, copper, gold, zinc oxide, titanium dioxide, iron oxide that most frequently occur in consumer products. In addition, NPs are addressed as the new aquatic environmental pollutant of the 21st century. NPs are adsorbed onto particles in the aquatic systems (clay minerals, fulvic and humic acids, or they can adsorb environmental pollutants (heavy metal ions, organic compounds. Nanosilver (nAg is released from consumer products into the aquatic environment. It can threaten aquatic organisms with high toxicity. Interestingly, copper nanoparticles (Cu-NPs demonstrate higher toxicity to bacteria and aquatic microorganisms than those of nanosilver nAg. Their small size and reactivity can cause penetration into the tissues and interfere with the metabolic systems of living organisms and bacterial biogeochemical cycles. The behavior of NPs is not fully recognized. Nevertheless, it is known that NPs can agglomerate, bind with ions (chlorides, sulphates, phosphates or organic compounds. They can also be bound or immobilized by slurry. The NPs behavior depends on process conditions, i.e. pH, ionic strength, temperature and presence of other chemical compounds. It is unknown how NPs behave in the aquatic environment. Therefore, the research on this problem should be carried out under different process conditions. As for the toxicity, it is important to understand where the differences in the research results come from. As NPs have an impact on not only aquatic organisms but also human health and life, it is necessary to recognize their toxic doses and know standards/regulations that determine the permissible concentrations of NPs in the environment.

Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms

Science.gov (United States)

Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.

2014-01-01

Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ≤ 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

Dual responsive dysprosium-doped hydroxyapatite particles and toxicity reduction after functionalization with folic and glucuronic acids.

Science.gov (United States)

Sánchez Lafarga, Ana Karen; Pacheco Moisés, Fermín P; Gurinov, Andrey; Ortiz, Genaro Gabriel; Carbajal Arízaga, Gregorio Guadalupe

2015-03-01

The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. Copyright © 2014 Elsevier B.V. All rights reserved.

Review of reproductive and developmental toxicity induced by organotins in aquatic organisms and experimental animals