The data indicated the presence of trace amounts of TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin), other chlorinated dioxins, chlorinated phenols, PBB (poly-brominated biphenyls), and PCB (polychlorinated biphenyl) in some of various samplings of fish, generally taken from the lower Tittabawassee River in Michigan. The TSCA 8 (e) Risk Evaluation Group has concluded that the data on TCDD do not appear to indicate a substantial risk of injury to human health or the environment. Dow is not a producer or processor of PBB or PCB. We are not familiar in detail with the effects information on these chemicals. The monitoring results cover selective analysis of water and mud from the river, the plant discharge stream, native fish from several locations above and below Dow's Midland plant, and a bioaccumulation study. The monitoring occurred during the period of latter 1976 through June, 1978.