Updated “Mixture Manual” Available from ATSDR

The Agency for Toxic Substances and Disease Registry has released “Framework for Assessing Health Impacts of Multiple Chemicals and Other Stressors,” a manual that describes a recommended process for evaluating the potential public health effects of exposures to multiple chemicals and other stressors, such as noise and radiation. The manual outlines a three-tier approach to integrating exposure data and epidemiologic and toxicologic data and assessing potential health effects from combined exposure to multiple agents. The manual is a revision of ATSDR’s 2004 publication “Guidance Manual for the Assessment of Joint Toxic Action of Chemical Mixtures” and reviews scientific advancements since 2000. The new “mixture manual” includes a chapter that discusses the issues involved in the assessment of health effects of exposures to multiple chemicals. The chapter presents background information on three approaches: use of exposure data and epidemiologic and toxicologic data for the actual mixture of concern; use of data for a sufficiently similar mixture; or use of data on the components of the mixture.  An appendix summarizes methods used or proposed by other agencies to assess health effects of mixtures, including methods from OSHA, NIOSH, and EPA.  ATSDR produces the manual in part to meet the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act, or CERCLA. The law mandates that the agency research the health effects of “priority hazardous substances” in cooperation with the National Toxicology Program, and to determine the health effects of substances that are commonly found in combination with other substances. “Framework for Assessing Health Impacts of Multiple Chemicals and Other Stressors” is available as a . For more information from ATSDR about mixtures of hazardous substances, visit the agency’s .