Environmental Contaminants in Birds: Phosphate-Mine and Natural Wetlands

摘要

Large ponds used to settle the waste clays from Florida's phosphate surface mining operations are attractive to waterfowl, and contain elevated levels of trace elements and radionuclides of the uranium series naturally associated with phosphate ore. Four species of waterfowl were sampled to investigate accumulation of radionuclides and trace elements and to evaluate potential deleterious effects for the birds and humans consuming them. Greater radium-226 levels in the substrate of the settling ponds than in natural wetlands were reflected in elevated concentrations in bones for all four species. Diet/substrate ratios were less than 1 for all species in all areas. Bone/substrate ratios differed between settling areas and natural wetlands. Radium-226 levels in soft tissues were consistently less than those in bones, and did not appear to represent an increased threat to humans eating the tissue.