Toxicity testing costs

Choi J-Y, Ramachandran G, Kandlikar M (2009) The impact of toxicity testing costs on nanomaterial regulation. Environ Sci Technol 43 3030-3034... 

Several antimicrobials have been banned or severely restricted by the EPA based on documented or suspected toxicity or environmental problems. Others have been discontinued in the face of testing costs required by the EPA reregistration program mandated by the Pederal Insecticide, Pungicide, and Rodenticide Act (PIPRA) of 1988 (10). Some of the significant products that have become obsolete are 2,4,5-trichlorophenol/P3 -5 3 -47, sodium... 

The advantages of combining toxicity testing with chemical analysis when dealing with complex mixtures of environmental chemicals are clearly evident. More useful information can be obtained than would be possible if one or the other were to be used alone. However, chemical analysis can be very expensive, which places a limitation on the extent to which it can be used. There has been a growing interest in the development of new, cost-effective biomarker assays for assessing the toxicity of mixtures. Of particular interest are bioassays that incorporate mechanistic... 

Such sentinel workflow uses a prediction to select compounds for a more expensive screen that can confirm predicted hazards (liabilities, such as toxicity). It is, provably, the best workflow in contexts where a low prevalence of the hazard is anticipated, and where there is a backstop means further downstream (e.g., preclinical toxicity testing) for detecting hazards before humans are exposed. This workflow then allows the compounds predicted as safe to bypass the expensive hazards screen, without unacceptable risk, and can add significant value in terms of external screening costs or avoiding use of what may be a bottleneck resource. 

Barata C, Alanon P, Gutierrez-Alonso S, Riva MC, Fernandez C, Tarazona JV (2008) A Daphnia magna feeding bioassay as a cost effective and ecological relevant sublethal toxicity test for environmental risk assessment of toxic effluents. Sci Total Environ 405(l-3) 78-86... 

Persoone, G. Van de Vel, A. Cost-Analysis of Five Current Aquatic Toxicity Tests Report EUR 11342 EN, Commission of the European Communities, 1988 119 pp. 

Persoone, G. Cyst-based toxicity tests. I. A promising new tool for rapid and cost-effective toxicity screening of chemicals and effluents. Zeitschr. Fiir Angewandte Zoologie 1991, 78, 235-241. 

Because of the pressing contemporary need to assess an ever-growing number of chemicals and complex environmental samples, the development and use of small-scale toxicity tests (also called micro-scale toxicity tests or microbiotests ) have increased because of their attractive features. Simply defined as a test involving the exposure of a unicellular or small multicellular organism to a liquid or solid sample in order to measure a specific effect , small-scale tests are generally simple to execute and characterized by traits which can include small sample volume requirements, rapid turnaround time to results, enhanced sample throughput and hence cost-effectiveness (Blaise et al., 1998a). 

Comparative studies involving toxicity tests abound in the scientific literature. There are many reasons compelling ecotoxicologists to conduct work of this nature, some of which are directed 1) to assess the performance, sensitivity and relevance of individual bioassays undertaken on various chemicals and (liquid and solid) media to specify their scope of use, 2) to optimize the diagnostic potential of bioassay batteries to broaden hazard detection (insure that tests in a battery are complementary and not redundant) and 3) to promote the application of novel assays capable of high throughput for cost-effective screening of (complex) environmental samples. 

Persoone, G., Blaise, C., Snell, T., Janssen, C. and Van Steertegem, M. (1993) Cyst-based toxicity tests II. - Report on an international intercalibration exercise with three cost-effective Toxkits, Zeitschrift fur Angewandte Zoologie 19 (1), 17-36. 

For both the Saint-Lawrence River Action Plan (Costan et al., 1993) and the Toyama Bay Japanese (Kusui and Blaise, 1999) studies, the two suites of bioassays employed represented three trophic levels (decomposers, primary producers and primary or secondary consumers), and sought to measure both acute and chronic toxicity. Toxicity tests were selected on the basis of practical and scientific criteria including low sample volume requirement, sensitivity, simplicity of undertaking the assay, ease in maintaining laboratory cultures, cost-effectiveness, procedural reliability and/or frequency of use internationally. 

Requiring low-sample volume micro-scale tests for its cost-effective application, the PEEP index has thus far employed bioassays with bacteria, algae and microinvertebrates. While well-standardized toxicity tests using freshwater fish existed at the time of the PEEP s conception in the early 1990 s (e.g., the Environment Canada fingerling rainbow trout 96-h lethality test to assess industrial wastewaters), they were excluded because of their large sample volume needs (e.g., close to 400 L of effluent sample required to undertake a multiple dilution 96-h LC50 bioassay in the case of the trout test). In addition to effluent sample volume, the cost of carrying out salmonid fish acute lethality bioassays for the 50 priority industrial effluents identified under SLAP I (the first 1988-93 Saint-Lawrence River Action Plan) was prohibitive. 

The use of a common battery of toxicity tests for effluents is a key feature for the management of the aquatic environment. The choice of the tests and the expression of results should be made as objective as possible to maximize the information on potential dangers and minimize cost. This text describes a procedure that was used in order to choose a test battery by means of a series of expert judgments and the use of modeling. 

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