Aquatic Toxicology

BLOOD GLUCOSE RESPONSE OF CLARIAS GARIEPINUSEXPOSED TO ACUTE CONCENTRATIONS OF GLYPHOSATE-ISOPROPYLAMMONIUM (SUNSATE®)

by Okomoda Victor

Co-authored by Ataguba G.A.. Published in Journal of Agriculture and Veterinary Sciences

Clarias gariepinus with mean weight 6.86g +0.34 obtained from a homogenous source
through induced breeding were... more Clarias gariepinus with mean weight 6.86g +0.34 obtained from a homogenous source
through induced breeding were exposed to different concentrations of Sunsate® for 96hours
using static bioassays with continuous aeration under laboratory conditions to determine the
acute toxicity of glyphosate in Sunsate® on the fish. LC50 of the exposed fingerlings were
found to be 17.5 mg l-1. The fish showed toxicosis symptoms such as loss of balance,
respiratory distress, vertical and erratic movement, accumulation of mucus on the body
surface and death. Result on blood glucose response shows that as the concentration
increases so the blood glucose, therefor precautious use of Sunsate®in the control of aquatic
weed is advised.

Evaluation of the quality of waters flowing into the Vistula River at the longitude of the city of Toruń by means of biotests with the use of Artemia salina and Hydra attenuata.

by Paweł Napiórkowski

The article based on lecture from II Conference ofPolish Ecotoxicological Societv Wrocław 2008

From April to October 2005, samples of surface waters were collected at 9 different sites within the city of Toruń... more From April to October 2005, samples of surface waters were collected at 9 different sites within the city of Toruń (tributaries of the Vistula River). Samples were subjected to ecotoxicological assessment with the use of biotests with Artemia salina and Hydra attenuata. Also, basic physicochemical parameters of the sampled water were measured. Based on the results of the mortality rate of tested organisms, LC50 and EC50 were calculated, and the toxicity of the studied waters was determined according to the Tonkes scale. It was found that the studied waters are nontoxic or slightly toxic. Also, the differences were observed among the studied organisms regarding the degree of sensitivity to the same tests.

Changes in non-specific biomarkers in the Mediterranean barbel (Barbus meridionalis) exposed to sewage effluents in a Mediterranean stream (Catalonia, NE Spain).

by Gines Viscor

Evaluation of Short-Term Fish Reproductive Bioassays for Predicting Effects of a Canadian Bleached Kraft Mill Effluent

by Steven Melvin

van den Heuvel MR, Martel PH, Kovacs TG, MacLatchy DL, Van Der Kraak GJ, Parrott JL, McMaster ME, O'Connor BI, Melvin SD, and LM Hewitt. 2010. Water Qual. Res. J. Can. 45(2):175-186

Under the Canadian Environmental Effects Monitoring (EEM) program for pulp and paper effluents, the observation of a... more Under the Canadian Environmental Effects Monitoring (EEM) program for pulp and paper effluents, the observation of a national response pattern of decreased gonad size and increased fish condition and liver size has triggered a centralized multiagency investigation of cause (IOC) of reproductive impacts in fishes. The purpose of the component of the IOC study presented here is to compare a number of fish bioassays for determining reproductive and reproductive-endocrine effects of a bleached kraft mill effluent. The bleached kraft mill chosen for this study had demonstrated the national response pattern in previous EEM cycles. The bioassays employed to examine reproduction were fathead minnow (Pimephales promelas) 5- and 21-d, mummichog (Fundulus heteroclitus) 25-d, and zebrafish (Danio rerio) 7-d tests, all of which had egg production as the primary reproductive endpoint. Additional bioassays examining reproductive-endocrine endpoints included a 7-d mummichog test, a 7- and a 21-d threespine stickleback (Gasterosteus aculeatus) test, a rainbow trout (Oncorhynchus mykiss) 7-d test, and in vitro sex steroid receptor and plasma protein binding bioassays. The zebrafish and fathead minnow reproductive tests showed significant suppression of egg production at the 100% effluent concentration. Endocrine data derived from the tests showed that this effluent did not impact steroidogenic endpoints at any concentration. Bioassays showed that this effluent i) was capable of eliciting cytochrome P4501A induction at as low as 10% vol/vol effluent, ii) was weakly androgenic at 10% vol/vol, and iii) showed no evidence of in vivo estrogenicity. These results were consistent with in vitro receptor binding assays showing a highly variable level of androgenic equivalents over six months of effluent testing, with little evidence of estrogenic activity. Bioassay results were consistent in that the overall conclusion was that this effluent has only a weak potential to cause reproductive impairment and would likely not do so at environmentally relevant concentrations. Field studies and a fathead minnow lifecycle study conducted concurrently were in agreement with reproductive bioassay results as white sucker exposed in the receiving environment no longer had significantly reduced gonadal development. Overall, this study provided evidence that the laboratory assays evaluated for various reproductive endpoints have potential application for future IOC work.

An individual–based modeling approach for evaluation of endpoint sensitivity in harpacticoid copepod life cycle tests and optimization of test design

by Thomas G. Preuss

T.G. Preuss, M.Brinkmann, E. Lundström, B.E. Bengtsson, M. Breitholtz

In the present study, an individual-based model for Nitocra spinipes was developed and used to optimize the test... more In the present study, an individual-based model for Nitocra spinipes was developed and used to optimize the test design of a proposed Organisation for Economic Co-operation and Development test guideline for harpacticoid copepods. The variability between individuals was taken into account, based on measured data, leading to stochastic model output. Virtual experiments were performed with the model to analyze the endpoint sensitivity and the effect of number of replicates and inspection intervals on statistical power. The impact of mortality was evaluated; most sublethal effects could not be determined if the mortality was ≥70%. Most sensitive to mortality was the determination of effects on brood size, for which the statistical power was reduced at 10% mortality. Our simulations show that increasing the number of replicates from 72 to 96 or 144 has little impact on the statistical power, whereas 25 replicates disallow relevant endpoint detection. Furthermore, it was demonstrated that the proposed 1D inspection interval can be shifted to a 3D interval, without losing statistical power. It was demonstrated that developmental endpoints have a higher statistical power than reproductive endpoints in the current test design. The present study highlights the usefulness of individual-based models for optimizing the experimental design. The use of such models in the development of standard test guidelines will lead to a faster and less resource-demanding process.

Evaluación de Impactos Ambientales Causados por Vertimientos Sobre Aguas Continentales

by Nelson Fernández

Coautoría con Alberto Ramírez y Ricardo Restrepo. Publicado en Revista Ambiente y Desarrollo-Universidad Javeriana (http://www.javeriana.edu.co/fear/ins_amb/rad12-13.htm)

En este documento se desarrolla una metodología de valoración para vertimientos a partir de dos indicadores... more En este documento se desarrolla una metodología de valoración para vertimientos a partir de dos indicadores ambientales. Esto es el índice de contaminación biológico ICOBIO y el índice de contaminación por toxicidad ICOTOX.

5 [alpha]-Dihydrotestosterone is a potent androgen in the fathead minnow (Pimephales promelas)

by Luigi Margiotta-Casaluci

Margiotta-Casaluci L. and Sumpter J.P.

General and Comparative Endocrinology, 2011.
171 (3):309-318.

Dihydrotestosterone (DHT) is one of the most physiologically important androgens in many male vertebrates, with the... more Dihydrotestosterone (DHT) is one of the most physiologically important androgens in many male vertebrates, with the exception of teleost fish, in which 11-ketotestosterone (KT) is generally considered the major circulating male androgen. In the present study, we investigated the effects of KT and DHT on fathead minnow juveniles (Pimephales promelas), with the aim to compare the effects of the two androgens on critical physiological processes, such as somatic growth, male secondary sexual characteristics expression, and gonad maturation. Juvenile fish (60 days post-hatch) were exposed to 20 and 200 ng/L of KT and DHT for 45 days. Exposure to both androgens significantly stimulated somatic growth in both males (20 and 200 ng/L) and females (200 ng/L). Nuptial tubercle formation was induced by both KT and DHT, but only the latter, at 200 ng/L, caused the appearance of dorsal fin spot in 92% of males and 75% of females. Circulating plasma T concentrations showed a sex-specific response; a significant increase was recorded in exposed males and a decrease in females. Both androgens induced a significant advancement of the spermatogenic processes in males at 200 ng/L. In contrast, only DHT caused a severe disruption of ovarian physiology and morphology in females, inducing the development of spermatogenic tissue (intersex). These results show that in fathead minnow juveniles, DHT had in vivo androgenic potency comparable to KT in males, and higher than KT in females, suggesting a potential involvement of DHT in the mediation of fathead minnow androgenic responses.

Pharmaceuticals in the Aquatic Environment: Steroids and Anti-Steroids as High Priorities for Research

by Luigi Margiotta-Casaluci

Tamsin Runnalls, Luigi Margiotta-Casaluci, Subramaniam Kugathas, John Sumpter

Human and Ecological Risk Assessment, 2010.
16 (6):1318-1338.

Many human pharmaceuticals, with many modes of action, are present in the aquatic environment. It is very difficult to... more Many human pharmaceuticals, with many modes of action, are present in the aquatic environment. It is very difficult to know which of these might pose a threat to aquatic organisms, and which are of no environmental concern. Hence, it is difficult to design a research strategy that most effectively maximizes the possibility of identifying those pharmaceuticals that do pose the greatest risk. We consider that steroidal pharmaceuticals, and drugs that inhibit the actions of endogenous steroids, merit more research than they have yet received so far. We analyzed a comprehensive U.K. database covering all prescriptions of pharmaceuticals to determine the annual usage of all steroid and anti-steroid pharmaceuticals. We found that both progestogens and glucocorticoids are used in much greater amounts than estrogens, whereas androgens are used in similar amounts to estrogens. There is also very significant use of anti-estrogens, anti-androgens, and anti-mineralocorticoids. All these pharmaceuticals are likely to be constantly entering the aquatic environment in effluents from sewage treatment works. River concentrations of these pharmaceuticals will be very low; probably in the ng or sub-ng/l range. However, such low concentrations mat still pose a threat to aquatic organisms, especially fish.

Landscape ecotoxicology of coho salmon spawner mortality in urban streams

by Blake Feist

Feist, BE, ER Buhle, P Arnold, JW Davis & NL Scholz (2011) Public Library of Science ONE 6(8): e23424. doi:10.1371/journal.pone.0023424

In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to... more In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to spawn in urban basins of the Puget Sound region have been prematurely dying at high rates (up to 90% of the total runs) for more than a decade. The current weight of evidence indicates that coho deaths are caused by toxic chemical contaminants in land-based runoff to urban streams during the fall spawning season. Non-point source pollution in urban landscapes typically originates from discrete urban and residential land use activities. In the present study we conducted a series of spatial analyses to identify correlations between land use and land cover (roadways, impervious surfaces, forests, etc.) and the magnitude of coho mortality in six streams with different drainage basin characteristics. We found that spawner mortality was most closely and positively correlated with the relative proportion of local roads, impervious surfaces, and commercial property within a basin. These and other correlated variables were used to identify unmonitored basins in the greater Seattle metropolitan area where recurrent coho spawner die-offs may be likely. This predictive map indicates a substantial geographic area of vulnerability for the Puget Sound coho population segment, a species of concern under the U.S. Endangered Species Act. Our spatial risk representation has numerous applications for urban growth management, coho conservation, and basin restoration (e.g., avoiding the unintentional creation of ecological traps). Moreover, the approach and tools are transferable to areas supporting coho throughout western North America.

The effect of synthetic surfactants on the hydrobiological mechanisms of water self-purification

by Sergei Ostroumov

A discovery: it is the first time it is proved that synthetic surfactants (and detergents) give rise to inhibition of the ecological mechanisms that improve water quality in aquatic (freshwater and marine) ecoystems.
**
more key words: ecology, Environment, Biology, Water Quality, Key relevant publications, Authored, and, co-authored, by, Dr., S. A. Ostroumov, personal care product formulations, household product formulations, discoveries, innovations, new, data, results, improving, key, important, biomachinery, fundamental, biological, effects, anthropogenic,

Ostroumov S.A. The effect of synthetic surfactants on the hydrobiological mechanisms of water self-purification. -... more Ostroumov S.A. The effect of synthetic surfactants on the hydrobiological mechanisms of water self-purification. - Water Resources. 2004. Volume 31, Number 5 p. 502-510. http://www.scribd.com/doc/41169530/WR502; DOI 10.1023/B:WARE.0000041919.77628.8d. [Long-term studies of the biological effect of surfactants, including the effect surfactants exert on filter feeders, are reviewed. The role of filter feeders in the functioning of freshwater and marine ecosystems is analyzed. New aspects in the assessment of environmental hazard due to the impact of chemical pollutants, including surfactants and detergents, are established]. In Russian: http://www.scribd.com/doc/57648905/4VodnResursy-R;

Main discoveries made by the same author:
Публикации того же автора. Основные результаты. Main Results: http://www.scribd.com/doc/59437439/;
On the author / Об авторе (С.А.О.):
http://www.famous-scientists.ru/3732/;

On some issues of maintaining water quality and self-purification.

by Sergei Ostroumov

It is the first time that an innovative conceptualization is given of how the biota (all aquatic organisms) of aquatic ecosystem function towards improving water quality. Also, some new experimental data were generated and presented in the paper. The paper is useful to increase water sustainability, it could be useful in university education as well.
more key words: ecology, Environment, Biology, Water Quality, Key relevant publications, Authored, and, co-authored, by, Dr., S. A. Ostroumov, personal care product formulations, household product formulations, discoveries, innovations, new, data, results, improving, key, important, biomachinery, fundamental, biological, effects, anthropogenic,

**
http://www.researchgate.net/profile/Sergei_Ostroumov/blog/9142_FAQBiotic_Self-purification_of_Aquatic_Ecosystems; FAQ on the paper:
S. A. Ostroumov. On the Biotic Self-purification of Aquatic Ecosystems: Elements of the Theory. — Doklady Biological Sciences. 2004. v.396, pp.206-211.

Ostroumov S. A. On some issues of maintaining water quality and self-purification.- Water Resources, 2005. Volume 32,... more Ostroumov S. A. On some issues of maintaining water quality and self-purification.- Water Resources, 2005. Volume 32, Number 3, p. 305-313. http://www.scribd.com/doc/57511892/0305 [Generalizations presented in this paper represent, in systematized form, the basic elements of the qualitative theory of water self-purification in freshwater and marine ecosystems. Recommendations are given for maintaining water quality and sustainable development of water resources.

New experimental data were generated: Results of experimental studies of the effect exerted by the surfactant Triton X-100 and the OMO synthetic detergent on freshwater bivaqlve mollusks, freshwater mussels Unio tumidus]. ISSN 0097-8078 (Print) 1608-344X (Online). DOI 10.1007/s11268-005-0039-7.

Main discoveries made by the same author:
Публикации того же автора. Основные результаты. Main Results: http://www.scribd.com/doc/59437439/;
On the author / Об авторе (С.А.О.):
http://www.famous-scientists.ru/3732/;

A Framework for Trait-based Assessment in Ecotoxicology.

by Thomas G. Preuss

RUBACH,M.N.; ASHAUER, R.; BUCHWALTER, D.B.; DE LANGE, H.J.; HAMER, M.; PREUSS, T.G.; TÖPKE, K.; MAUND, S.J.
Integr. Environ. Assess. Manag. 7(2):172-186.

A key challenge in ecotoxicology is to assess the potential risks of chemicals to the wide range of species in the... more A key challenge in ecotoxicology is to assess the potential risks of chemicals to the wide range of species in the environment on the basis of laboratory toxicity data derived from a limited number of species. These species are then assumed to be suitable surrogates for a wider class of related taxa. For example, Daphnia spp. are used as the indicator species for freshwater aquatic invertebrates. Extrapolation from these datasets to natural communities poses a challenge because the extent to which test species are representative of their various taxonomic groups is often largely unknown, and different taxonomic groups and chemicals are variously represented in the available datasets. Moreover, it has been recognized that physiological and ecological factors can each be powerful determinants of vulnerability to chemical stress, thus differentially influencing toxicant effects at the population and community level. Recently it was proposed that detailed study of species traits might eventually permit better understanding, and thus prediction, of the potential for adverse effects of chemicals to a wider range of organisms than those amenable for study in the laboratory. This line of inquiry stems in part from the ecology literature, in which species traits are being used for improved understanding of how communities are constructed, as well as how communities might respond to, and recover from, disturbance (see other articles in this issue). In the present work, we develop a framework for the application of traits-based assessment. The framework is based on the population vulnerability conceptual model of Van Straalen in which vulnerability is determined by traits that can be grouped into 3 major categories, i.e., external exposure, intrinsic sensitivity, and population sustainability. Within each of these major categories, we evaluate specific traits as well as how they could contribute to the assessment of the potential effects of a toxicant on an organism. We then develop an example considering bioavailability to explore how traits could be used mechanistically to estimate vulnerability. A preliminary inventory of traits for use in ecotoxicology is included; this also identifies the availability of data to quantify those traits, in addition to an indication of the strength of linkage between the trait and the affected process. Finally, we propose a way forward for the further development of traits-based approaches in ecotoxicology.

General unified theory of survival - a toxicokinetic and toxicodynamic framework for ecotoxicology

by Thomas G. Preuss

JAGER, T.; ALBERT, C; PREUSS, T.G; ASHAUER R
Env. Sci. Technol. 45 (7): 2529–2540

Toxicokinetic-toxicodynamic models (TKTD models) simulate the time-course of processes leading to toxic effects on... more Toxicokinetic-toxicodynamic models (TKTD models) simulate the time-course of processes leading to toxic effects on organisms. Even for an apparently simple endpoint as survival, a large number of very different TKTD approaches exist. These differ in their underlying hypotheses and assumptions, although often the assumptions are not explicitly stated. Thus, our first objective was to illuminate the underlying assumptions (individual tolerance or stochastic death, speed of toxicodynamic damage recovery, threshold distribution) of various existing modeling approaches for survival and show how they relate to each other (e.g., critical body residue, critical target occupation, damage assessment, DEBtox survival, threshold damage). Our second objective was to develop a general unified threshold model for survival (GUTS), from which a large range of existing models can be derived as special cases. Specific assumptions to arrive at these special cases are made and explained. Finally, we illustrate how special cases of GUTS can be fitted to survival data. We envision that GUTS will help increase the application of TKTD models in ecotoxicological research as well as environmental risk assessment of chemicals. It unifies a wide range of previously unrelated approaches, clarifies their underlying assumptions, and facilitates further improvement in the modeling of survival under chemical stress.

Arsenic Contamination of Groundwater in Nepal—An Overview

by Jay Krishna Thakur

http://www.mdpi.com/2073-4441/3/1/1/

Abstract: In Nepal, arsenic (As) contamination is a major issue of current drinking water supply systems using... more Abstract: In Nepal, arsenic (As) contamination is a major issue of current drinking water supply systems using groundwater and has recently been one of the major environmental health management issues especially in the plain region, i.e., in the Terai districts, where the population density is very high. The Terai inhabitants still use hand tube and dug wells (with hand held pumps that are bored at shallow to medium depth) for their daily water requirements, including drinking water. The National Sanitation Steering Committee (NSSC), with the help of many other organizations, has completed arsenic blanket test in 25 districts of Nepal by analysing 737,009 groundwater samples. Several organizations, including academic institutions, made an effort to determine the levels of arsenic concentrations in groundwater and their consequences in Nepal. The results of the analyses on 25,058 samples tested in 20 districts, published in the status report of arsenic in Nepal (2003), demonstrated that the 23% of the samples were containing 10–50 µg/L of As, and the 8% of the samples were containing more than 50 µg/L of As. Recent status of over 737,009 samples tested, the 7.9% and 2.3% were contaminated by 10–50 µg/L and >50 µg/L, respectively of As. The present paper examines the various techniques available for the reduction of arsenic concentrations in Nepal in combination with the main results achieved, the socio-economic status and the strategies. This paper aims to comprehensively compile all existing data sets and analyze them scientifically, by trying to suggest a common sustainable approach for identifying the As contamination in the nation, that can be easily adopted by local communities for developing a sustainable society. The paper aims also to find probable solutions to quantify and mitigate As problem without any external support. The outcome of this paper will ultimately help to identify various ways for: identify risk areas; develop awareness; adopt the World Health Organization (WHO) guideline; identify alternative safe water sources and assess their sustainability; give priorities to water supply and simple eco-friendly treatment techniques; investigate impacts of arsenic on health and agriculture; strengthen the capability of government, public, Non-governmental Organization (NGO) and research institutions.

Keywords: arsenic; arsenic contamination in groundwater of Nepal; drinking water; groundwater resources management

Free download:
http://www.mdpi.com/2073-4441/3/1/1/

Mercury trophic transfer in a eutrophic lake: the importance of habitat-specific foraging

by Collin Eagles-Smith

Published in Ecological Applications, 2008

Invasive fish induced effect on food web mercury bioaccumulation

by Collin Eagles-Smith

Published in Ecological Applications, 2008

Rapid changes in mercury concentrations of small estuarine fish

by Collin Eagles-Smith

Published in Environmental Science and Technology, 2009