Mussel watch results from 1986 to 1996

Mussel Watch results from coastal waters of the United States for 1986 through 1996 show decreasing trends in molluscan concentrations of chlorinated hydrocarbons, butyltins, and cadmium. Weaker cases for decreases exist for copper, zinc, and silver. Concentrations of polycyclic aromatic hydrocarbons, arsenic, mercury, nickel, lead, and selenium show no overall trend.