Future Directions in Research on the Genetic Toxicology of Complex Mixtures

Abstract

The recognition that most human exposure to environmental chemicals occurs as exposures to complex mixtures has stimulated research on the toxicology of complex mixtures (36). The future assessment of complex mixtures of environmental pollutants will increasingly rely on new interdisciplinary strategies including state-of-the-art genetic and molecular methodologies. Integrated multidisciplinary studies are now beginning to assess human exposure, dosimetry, and cancer risk relative to complex mixtures of pollutants, and to apportion the human exposure and risk to various sources. Strategies which hold promise for incorporation of genetic bioassay data in the risk assessment of complex mixtures include: (i) biomonitoring environmental levels, fate, transformation, and human exposure; (ii) characterization of the genotoxic components of complex mixtures using advanced chemical and bioassay methods; (iii) molecular dosimetry of complex mixtures; and (iv) mechanistic studies of the effects of complex mixtures induced by both genetic and nongenetic mechanisms. Important advances in understanding the genetic and carcinogenic effects of complex environmental mixtures will increasingly rely on the successful implementation of multidisciplinary integration of environmental, laboratory, and human studies using state-of-the-art biological, chemical, and molecular methods.