Author(s)

H. R. Pohl, M. Fay & J. F. Risher

Abstract

The Agency for Toxic Substances and Disease Registry (ATSDR) program for chemical mixtures risk assessment has prepared a guidance document (Guidance Manual for the Assessment of Joint Toxic Action of Chemical Mixtures) that instructs how to conduct health risk assessment for chemical mixtures. ATSDR also develops documents called \“interaction profiles” to assess risks associated with exposure to specific chemical mixtures. The assessment method has been applied in practice during consultations in communities around hazardous waste sites. Interaction profiles are written for mixtures of concern that are on ATSDR’s priority list of mixtures at hazardous waste sites, such as mixtures of VOCs most often found in water and mixtures of metals most often found in contaminated soils. Similarly, interaction profiles on persistent lipophilic chemicals found in fish and breast milk provide information on risk associated with exposures in everyday life. In support of the US Geological Survey (USGS), ATSDR has developed an interaction profile for a mixture of pesticides found in well water. In addition, interaction profiles have been developed for Department of Energy (DOE) and National Aeronautics and Space Administration (NASA) sites. These interaction profiles were unique in evaluating risk associated with exposures to radioactive and non-radioactive chemicals. Weight-of-evidence methodology was used to assess the joint toxic action for most of the mixtures. For most mixtures profiled so far, a target-organ toxicity dose modification of the hazard index approach was utilized for conducting exposure-based assessments of noncancer health hazards. Keywords: chemical mixtures, risk assessment, radioactive chemicals, additivity, joint toxic action.

Keywords

chemical mixtures, risk assessment, radioactive chemicals, additivity, joint toxic action.