Organochlorine residues in shellfish from Maryland waters, 1976–1980

Abstract
Shellfish samples, including the American oyster (Crassostrea virginica), the soft shell clam (Mya arenaria), the hard shell clam (Mercenaria mercenaria) and the blue crab (Callinectes sapidus), were taken from the Maryland section of the Chesapeake Bay and its tributaries over 5 yr (1976-1980) and analyzed to determine residue levels of organochlorine pesticides. Qualitative and quantitative information was obtained for polychlorinated hydrocarbons. The purpose of this study included the establishment of baseline values for levels of shellfish contamination, utilization of the data as an indicator of probable levels of water and sediment contamination in the vicinity of the sampling site and ensurance that shellfish harvested for human consumption were within USA Food and Drug Administration [FDA] guidelines for organochlorine contamination. All mean values and virtually all individual values were within FDA guidelines.