U.S. EPA Regulatory Perspectives on the Use of QSAR for New and Existing Chemical Evaluations
ABSTRACT As testing is not required, ecotoxicity or fate data are available for approximately 5% of the approximately 2,300 new chemicals/year (26,000 + total) submitted to the US-EPA. The EPA's Office of Pollution Prevention and Toxics (OPPT) regulatory program was forced to develop and rely upon QSARs to estimate the ecotoxicity and fate of most of the new chemicals evaluated for hazard and risk assessment. QSAR methods routinely result in ecotoxicity estimations of acute and chronic toxicity to fish, aquatic invertebrates, and algae, and in fate estimations of physical/chemical properties, degradation, and bioconcentration. The EPA's Toxic Substances Control Act (TSCA) Inventory of existing chemicals currently lists over 72,000 chemicals. Most existing chemicals also appear to have little or no ecotoxicity or fate data available and the OPPT new chemical QSAR methods now provide predictions and cross-checks of test data for the regulation of existing chemicals. Examples include the Toxics Release Inventory (TRI), the Design for the Environment (DfE), and the OECD/SIDS/HPV Programs. QSAR screening of the TSCA Inventory has prioritized thousands of existing chemicals for possible regulatory testing of: 1) persistent bioaccumulative chemicals, and 2) the high ecotoxicity of specific discrete organic chemicals.
- SourceAvailable from: Patricia Ruiz
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- "For instance, the U.S. Food and Drug Administration Center for Food Safety and Applied Nutrition and Center for Drug Evaluation and Research and U.S. Environmental Protection Agency Office of Pollution Prevention and Toxics regulate chemicals of environmental, nutritional and pharmacologic significance, respectively, under the Pollution Prevention Act (42 U.S.C. 6601–6610), Toxic Substances Control Act (15 U.S.C. 2601–2692), Food Quality Protection Act (7 U.S.C. 136 et seq.), and other legislative authorities. As the number and diversity of new chemicals continues to rise (Nabholz et al., 1997), these agencies have approached the challenge by introducing (Quantitative) Structure–Activity Relationship ((Q)SAR) based guidance and decision support to chemical risk assessment (Auer et al., 1990; Klopman et al., 2005; Zeeman et al., 1995). The process of scientific risk assessment involves four steps, two of which, hazard identification and hazard characterization, can be approached by (Q) SAR. "
ABSTRACT: Methods of (Quantitative) Structure-Activity Relationship ((Q)SAR) modeling play an important and active role in ATSDR programs in support of the Agency mission to protect human populations from exposure to environmental contaminants. They are used for cross-chemical extrapolation to complement the traditional toxicological approach when chemical-specific information is unavailable. SAR and QSAR methods are used to investigate adverse health effects and exposure levels, bioavailability, and pharmacokinetic properties of hazardous chemical compounds. They are applied as a part of an integrated systematic approach in the development of Health Guidance Values (HGVs), such as ATSDR Minimal Risk Levels, which are used to protect populations exposed to toxic chemicals at hazardous waste sites. (Q)SAR analyses are incorporated into ATSDR documents (such as the toxicological profiles and chemical-specific health consultations) to support environmental health assessments, prioritization of environmental chemical hazards, and to improve study design, when filling the priority data needs (PDNs) as mandated by Congress, in instances when experimental information is insufficient. These cases are illustrated by several examples, which explain how ATSDR applies (Q)SAR methods in public health practice.Toxicology and Applied Pharmacology 10/2010; 254(2):192-7. DOI:10.1016/j.taap.2010.10.017 · 3.71 Impact Factor
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- "The agency uses these methods to fill data gaps in an assessment and to validate submitted data in notifications (Nabholz 2001). Predictions are made by the U.S. EPA Office of Pollution Prevention and Toxics (OPPT) under TSCA (Zeeman et al. 1995). The OPPT has routinely used QSARs to predict ecologic hazards, fate, and risks of new industrial chemicals, as well as to identify new chemical testing needs, for more than two decades. "
ABSTRACT: This article is a review of the use, by regulatory agencies and authorities, of quantitative structure-activity relationships (QSARs) to predict ecologic effects and environmental fate of chemicals. For many years, the U.S. Environmental Protection Agency has been the most prominent regulatory agency using QSARs to predict the ecologic effects and environmental fate of chemicals. However, as increasing numbers of standard QSAR methods are developed and validated to predict ecologic effects and environmental fate of chemicals, it is anticipated that more regulatory agencies and authorities will find them to be acceptable alternatives to chemical testing.Environmental Health Perspectives 09/2003; 111(10):1376-90. DOI:10.1289/ehp.5759 · 7.98 Impact Factor