Tissue distribution of heavy metals in heron and egret chicks from Pyeongtaek, Korea.

Iron, zinc, manganese, lead and cadmium were measured in the liver, kidney and bone of Grey Heron (Ardea cinerea), Intermediate Egret (Egretta intermedia), Little Egret (Egretta garzetta) and Black-crowned Night Herons (Nycticorax nycticorax) from Korea. Iron, zinc, manganese, lead and cadmium concentrations had species- and tissue- specific accumulation. Lead concentrations in all tissues of Black-crowned Night Heron and cadmium in kidneys of Intermediate Egret chicks were relatively higher than in other species. Iron and manganese in the liver, zinc in the bone, and lead and cadmium in the kidney were relatively higher than other tissues and these results have been reported in other birds. Lead concentrations in all species were at a level associated with acute lead poisoning and cadmium concentrations except for Grey Heron chicks were at a level associated with chronic cadmium exposure. Lead concentrations in livers and bones of heron and egret chicks were within a range considered background level (<6.00 μg/g dw). But, lead concentrations in kidneys of 12 of 37 heron and egret chicks were at concentrations associated with lethal lead poisoning (6.00-18 μg/g dw) and 7 of 37 chicks were compatible with death (>18.0 μg/g dw). For cadmium, all liver and kidney concentrations were at a level considered background for birds (<3.00 μg/g dw). Essential elements such as iron, zinc and manganese concentrations were within the range observed in other birds.