Critical knowledge gaps and relevant variables requiring consideration when performing aquatic ecotoxicity assays (original) (raw)

Aquatic concentrations of chemical analytes compared to ecotoxicity estimates

The Science of the total environment, 2017

We describe screening level estimates of potential aquatic toxicity posed by 227 chemical analytes that were measured in 25 ambient water samples collected as part of a joint USGS/USEPA drinking water plant study. Measured concentrations were compared to biological effect concentration (EC) estimates, including USEPA aquatic life criteria, effective plasma concentrations of pharmaceuticals, published toxicity data summarized in the USEPA ECOTOX database, and chemical structure-based predictions. Potential dietary exposures were estimated using a generic 3-tiered food web accumulation scenario. For many analytes, few or no measured effect data were found, and for some analytes, reporting limits exceeded EC estimates, limiting the scope of conclusions. Results suggest occasional occurrence above ECs for copper, aluminum, strontium, lead, uranium, and nitrate. Sparse effect data for manganese, antimony, and vanadium suggest that these analytes may occur above ECs, but additional effect...

Development of Methods for Evaluating Toxicity to Freshwater Ecosystems

Ecotoxicology and Environmental Safety, 2000

This article presents a summary of a collaborative research program involving 5ve European research groups, that was partly funded by the European Commission under its Environmental Research Program. The objective of the program was to develop aquatic toxicity tests that could be used to obtain data for inclusion at Level 2 of the Risk Evaluation Scheme for the Noti5cation of Substances as required by the 7th Amendment to EC Directive 79/831/EEC. Currently only a very limited number of test methods have been described that can be used for this purpose and these are based on an even smaller number of test species. Tests based upon algae (Chlamydomonas reinhardi, Scenedesmus subspicatus, and Euglena gracilis), protozoa (Tetrahymena pyriformis), rotifera (Brachionus calyciflorus), crustacea (Gammarus pulex), and diptera (Chironomus riparius) were developed. The tests encompassed a range of end points and were evaluated against four reference chemicals: lindane, 3,4dichloroaniline (DCA), atrazine, and copper. The capacity of the tests to identify concentrations that are chronically toxic in the 5eld was addressed by comparing the e4ects threshold concentrations determined in the laboratory tests with those determined for similar and/or related species and end points in stream and pond mesocosm studies. The lowest no-observed-e4ect concentrations (NOEC), EC x , or LC x values obtained for lindane, atrazine, and copper were comparable with the lowest values obtained in the mesocosms. The lowest chronic NOEC determined for DCA using the laboratory tests was approximately 200 times higher than the lowest NOEC in the mesocosms.

The state of the aquatic environment as deducted from bioassays-quantitated ecosystem risks

2007

Bioassays represent powerful tools for the assessment of environmental quality. This report focuses on the measurement of the toxicity of surface water samples towards a battery of several differing aquatic organisms. The toxicity is determined by isolating toxic organic chemicals from the surface water by use of a concentration procedure, and by exposing the organisms to the concentrates thus obtained. Subsequently this method evaluates the results statistically, to yield a measure for the degree to which the water represents a risk for the aquatic ecosystem. This risk is expressed in terms of 'toxic potency' which represents the fraction of the ecosystem that is affected in any way by the environmental conditions.

Anthropogenic Pollutants: 10 Years of Progress in Ecotoxicological Studies and Aquatic Risk Assessment

Romanian Journal of Ecology & Environmental Chemistry

The market expansion due to globalization generated more anthropogenic contaminants, enhancing their negative impact on the environment. In order to prevent and balanced their negative effect, more rapid, sensitive and eco-friendly ecotoxicological studies as risk assessments were developed. Each country developed national programs to ensure the research infrastructure for implementation and development of new testing methodologies, generating new experimental data transferable to governmental authorities, economic agents and academia. In this review, we intend to highlighted the progress of Romanian researchers in the last 10 years in the field of ecotoxicology and aquatic risk assessment. The studies focused on aquatic systems as a non-targeted system to the anthropogenic pollutants impact. The implemented methodologies according with international requirements for chemical control like REACH Regulation, Detergents Regulation, Biocide Products Regulation or the Aquatic Risk Assess...

Toxicological benchmarks for screening potential contaminants of concern for effects on aquatic biota: 1994 Revision

1994

This report supersedes a prior aquatic benchmarks report (Suter and Mabrey 1994). It adds two new types of benchmarks. It also updates the benchmark values where appropriate, adds some new benchmark values, replaces secondary sources with primary sources, and provides more complete documentation of the sources and derivation of all values. xiii Table 1. Summary of conventional benchmarks for priority contaminants in fresh water (all values in micrograms per liter) NAWQ Criteria Tier I1 Values Lowest Chronic Value for: Chemical Acute Chronic Secondary Secondary Fish Daphnids Non-Aquatic All Organ-Acute Chronic Daphnid Plants isms Value Value Invertebrates Aluminum 750 87 3,288 1,900 460 460 Ammonia pH and temperature dependent 1.7 Boron Cadmium Calcium Chromium I11 Chromium VI * 1.042 *332

Surface water toxicity assessment by ecotoxicological andin vitrotoxicologocical assays

WIT Transactions on Ecology and the Environment, 2008

Environmental pollution is an ever-growing problem in today's consumer world. Disposal of chemicals and their unwanted by-products into the natural environment poses significant risks to ecosystems and human health. The receiving natural environment is a sink to chemical mixtures and this triggers a range of potential environmental and health problems. It is therefore imperative to develop rapid reliable techniques for initial screening and establishment of toxic potential and risks. The selection of the catchment study locations in Tasmania (creeks stream and rivers) was the result of recorded observations following rainfall of anomalous oyster population mortality and adverse human health in the geographical catchment area. A biological impact was identified in the study area but the casual agents and environmental triggers were unclear hence the need for in vitro toxicology assessment techniques for identifying the triggers and risks associated with exposure to environmental contaminants. The aim of this paper is to present findings of in vitro cytotoxicity assays and their potential in assessing contaminated river water toxicity using human cell cultures. The key to the approach adopted was to investigate exposure to the environmental pollutants and generate human toxicity profiles with a high degree of confidence using cell viability and damage as end points. Furthermore, correlation of the toxicity results using human cell cultures as ecological receptors in the study area clearly indicated the usefulness of and sensitivity of human-derived cells in detecting the toxicity of unknown chemical mixtures.

Toxicity Assessment and Identification for Protection of Natural Waters

Canadian Water Resources Journal, 2002

Conventional pollution prevention strategies for the protection of natural waters usually entail a comparison of analytical results with water quality guidelines. This comparison is often compromised by the inability to identify fu1ly the toxicants in the environment and the need to reference current toxicological databases containing large datagaps. In light of these shortcomings, we describe examples of an alternative approach based on toxicity testing coupled with chemical manipulation and directed chemical analysis. Advantages of this toxicological approach over traditional methods are illustrated for natural water surveys conducted in North America and Mexico. It is demonstrated that toxicity identification evaluation is well suited to the development of water quality criteria for the protection of aquatic ecosystems. REsUME Les strat6gies traditionnelles de pr6vention de 1a pollution pour la protection des eaux naturelles supposent habituellement la comparaison des rdsultats analytiques avec les lignes directrices en matiCre de qualitd de l'eau. Cette comparaison est souvent compromise par I'incapacitd d'identifier de manidre int6grale les substances toxiques dans I'environnement et le besoin de se r6f6rer iL des bases de donn6es toxicologiques actuelles qui pr6sentent de grandes lacunes statistiques. A la lumidre de ces faiblesses, nous d6crivons des exemples d'une autre approche bas6e sur des essais de toxicit6 combin6s d la manipulation chimique et iL l'analyse chimique dirigde. Les avantages de cette approche toxicologique par rapport aux mdthodes traditionnels sont illustrds pour 1es relev6s hydrologiques (eaux naturelles) 6tablis en Amdrique du Nord et au Mexique. I1 a 6t€ d6montr6 que 1'6valuation des donndes sur la toxicitd est bien adaptde d 1'6laboration des critdres de qualit6 de i'eau pour la protection des 6cosystdmes aquatiques.

Biomarkers and PAHs — Prospects for the Assessment of Exposure and Effects in Aquatic Systems

Ecological and Environmental Toxicology Series, 2003

The fields of environmental toxicology, ecological toxicology and ecotoxicology are rapidly expanding areas of research. This explosion of interest within the international scientific community demands comprehensive and up-to-date information that is easily accessible to both professionals and an increasing number of students with an interest in these subject areas.