Use of oysters as indicators of copper contamination in the Patuxent River, Maryland

Abstract

The Patuxent River flows into the Chesapeake Bay from its western shore. Historically, the river has been implicated as having been contaminated with copper since the mid-1960's when a steam electric generating plant was built at Chalk Point, 35 km from the mouth of the river . Greening of oysters was noted by Roosenberg (1969) who reported copper levels in oysters from trays set close to the outfall in excess of 1000 μg g dry weight ' . It was claimed that the copper contamination derived from the coppernickel condenser tubing used for cooling two of the four generating units at the Chalk Point Plant . Units 3 and 4 used cooling towers for cooling purposes . In the early 1980's, a detailed study of copper output from the plant was undertaken in this laboratory and by Abbe & Sanders (1986) . The Abbe and Sanders (1986) study was confined to the immediate vicinity of Chalk Point, whereas the current study was extended from Holland Cliff (River Km 45) to Solomons, 3 km from the river mouth. Data describing dissolved and particulate copper concentrations in Patuxent River water have been described in a companion paper (Wright & Zamuda, 1990), which creates a budget for copper input to the river . In the current paper, we describe the bioavailable copper in the Patuxent River as defined by body burdens in