Effect of environs and seasonality on metal residues in tissues of wild and pond-raised crayfish in southern Louisiana.

Two commercially important species of Louisiana crayfish, Procambarus clarkii (Girard) and P. acutus acutus (Girard), from the Atchafalaya River Basin, from open ponds and from the sediment and water of these environs were sampled three times during two consecutive fishing (production) seasons. The abdominal muscle and hepatopancreatic tissue were analyzed separately. Lead, mercury, and cadmium, if present, were in concentrations below the detection limit. In the hepatopancreatic tissue, barium was present in concentrations below 8 mg/kg, copper 11-15 mg/kg, and iron below 640 mg/kg. Abdominal muscle samples had less than 3 mg/kg of most metals. Locations with the highest levels of metal residues in sediment were not necessarily locations where crayfish had the highest levels in their tissues.