ABSTRACT In this competitive renewal of the Ruth L. Kirschstein NRSA Institutional Research Training Grant Application, we request funds to support the research training in environmental toxicology at the University of California Riverside. The proposed interdisciplinary research training program is built upon the solid foundation of the existing curriculum structure of the environmental toxicology graduate program. The eighteen preceptors are from the Division of Biomedical Sciences as well as the Departments of Chemistry, Biochemistry, Botany and Plant Science, MCSB (Molecular, Cell and Systems Biology), and Environmental Sciences. They have been very actively engaged in training pre- and postdoctoral individuals in environmental toxicology, and their research projects have been well funded. The research programs of these faculty members include genetic toxicology and epigenetics, analytical chemistry and proteomics, developmental toxicology, and endocrine disruption and metabolism. Pre-doctoral trainees will be selected from the participating Chemistry and Environmental Toxicology graduate programs. An Internal Steering Committee is established to select trainees and monitor progress of trainees, and an External Advisory Board is also named to assist the management of the training program. A total of 9 trainees per year (7 pre-doctorates + 2 postdoctorates) are requested. The trainees will be exposed to multi-disciplinary research involving a variety of cutting-edge technologies in nanofabrication, genomics, proteomics, metabolomics, etc. The request for continued funding of this research training grant is justified by the relevance of the proposed research training to environmental health, the excellent training environment, the superb training experience of the preceptors, the strong institutional commitment, the diverse graduate student body at the University, as well as our success in recruiting, appointing and nurturing the success of trainees in the last two funding cycles.