The goal of this contract is to provide support of National Toxicology Program (NTP) hazard identification (or hazard assessment) activities targeted toward the prevention of diseases or adverse effects caused by environmental exposure to chemical or physical agents. Spent process streams from the manufacture of styrene-acrylonitrile have migrated into groundwater in certain locations in New Jersey. Increased incidences of certain forms of cancer in children, specifically types of leukemias and neurological cancers, have been observed in the vicinity of this groundwater contamination. Studies were designed to determine the potential toxicity of this previously untested mixture in rats exposed in utero and after birth. Pregnant female F344 rats received feed treated with the test chemical (at 5 concentrations plus feed controls) starting on gestational day 7 and continuing until the end of lactation/weaning of pups. Up to 3 male and female pups from each litter then continued on the same treatment as their dam for an additional period of time. The preliminary 7-week study involved treatment of pups in utero and continuing for 2 weeks post weaning to determine doses to be used in the subsequent 18-week study. The 18-week study was designed similar to the preliminary study, except that pups continued treatment for 13-weeks post weaning, and urinalysis, hematology, clinical chemistries and SMVC evaluations were conducted. Results observed in these studies were used to select doses for the 2-year carcinogenicity study which began in March, 2005 and has now been completed and reported. Keywords Carcinogenicity; toxicity; bioassay; F344 rats; SAN-trimer; styrene-acrylonitrile trimer; perinatal exposure.
