BIO-MAGNIFICATION OF HEAVY-METALS BY ORGANISMS IN A MARINE MICROCOSM

Protection of the public health requires that marine organisms used for food be protected from contamination by heavy metals which are potentially toxic to the consumer. Bioaccumulation of heavy metals by oysters, clams, crabs, shrimp, and fish in near-shore environments has been shown in a number of investigations. The objective of this investigation was to study possible pathways of bioaccumulation by determining the relative bioaccumulation of ten selected, potentially toxic metals by the marine organisms comprising limited microcosms in two Texas bays. Results indicate that the food organisms (crab, oyster, and clam) residing in the Texas bay microcosms are the least likely of the entire population to biomagnify the ten heavy metals studied. Crabs biomagnified less than the attached, filter feeding oysters and clams.