The environmental scoring of chemicals is viewed by the US Environmental Protection Agency as a tool to assist in the ranking or ordering of the universe of chemicals that are under the jurisdiction of the Toxic Substances Control Act. The purpose of scoring is to identify most of the chemicals that have a high probability for requiring review for regulation or testing. This report describes a three-day workshop held in Washington, DC, August 13 to 15, 1979, to develop an environmental scoring system. Initial discussions centered on the determination of a safety factor (calculated as the concentration at which an effect is observed divided by environmental concentration) that would allow a numerical score to be assigned to a chemical to reflect its potential hazard. Further discussion, however, indicated that the environmental concentration of a chemical is usually not available and that the estimation of an environmental concentration is not readily accomplished; therefore, a scoring system was developed that does not require environmental concentrations. This system relates environmental exposure to toxicity by using a multiplier (3x, 2x, or 1x) which is assigned on the basis of the concentration xt which an effect is observed. The applicability of the scoring system is demonstrated by scoring selected chemicals. (ERA citation 05:027989)

"Health and Environmental Studies Program, Information Center Complex/Information Division, Oak Ridge National Laboratory." "May 1980." Includes bibliographical references. "Contract no. W-7405-eng-26." "ORNL/EIS-158." "EPA/560-11-80-010."