Support: Letter from Dow to USEPA Summarizing Preliminary Results of a 90-Day Oral (Gavage) and 1-Generation Reproductive Toxicity Study of Trifluoropropylmethy lcyclotrisiloxane, dated 09/04/2001

摘要

Preliminary results from an ongoing 13-week subchronic and one generation reproductive study with TFPMCT show test article-related changes in liver, heart, and skeletal muscle. In the liver, periportal hepatocyte enlargement with micro to macrovacuolation of the cytoplasm was observed at a Lowest Observed Effect level (LOEL) of 0.8 mg/kg/day. In the heart, test article-related or test article-exacerbated cardio- myopathy was observed at a LOEL of 4.0 mg/kg/day (and possibly at 0.8 mg/kg/day in males). Degeneration in the skeletal muscle was seen at a LOEL of 20 mg/kg/day and was characterized by changes in the shape and size of myocytes, loss of cross striations, and increased cellularity (mononuclear inflammatory cells and/or regenerative myocyte nuclei).