Shell disease and metal content of blue crabs, Callinectes sapidus, from the Albemarle-Pamlico Estuarine System, North Carolina

Concentrations of 13 elements were determined for three tissues (gill, hepatopancreas, muscle) in diseased crabs from a contaminated estuary (Pamlico River, NC), and in non-diseased crabs from both the contaminated estuary and a relatively uncontaminated area (Albemarle Sound, NC) during the fall 1989 and summer 1990. The diseased crabs had lesions which completely penetrated their dorsal integument, while the non-diseased crabs lacked lesions. Sediments within the contaminated area showed enrichment of arsenic, cadmium, manganese, titanium and vanadium relative to the uncontaminated area. Levels of aluminum, arsenic, cobalt, manganese, nickel, titanium, vanadium and zinc were significantly higher in both gill and hepatopancreas in crabs from the contaminated area. Manganese was always highest in the diseased crabs in all tissues measured. The concentrations of the remaining elements were greater in the gills of diseased crabs, while highest values of these elements in the hepatopancreas varied among the diseased and non-diseased crabs from the polluted area. Conversely, copper levels were always highest in all tissues in crabs from the uncontaminated area, and typically lowest in the diseased crabs. Concentrations of aluminum and arsenic were also significantly greater in the muscle tissue of crabs from the contaminated area, but no distinct trend was evident with regard to diseased versus non-diseased crabs. Arsenic was the only element accumulated by crabs in the contaminated area which has a known toxic affect on the tissue responsible for cuticle synthesis and repair (hypodermis) in crustaceans. Metals also accumulated could possibly act synergetically to compromise normal metabolism.