Avian liver organochlorine and PCB from South coast of the Caspian Sea, Iran.

Liver samples (n = 43) of 9 avian species representing the families Phalacrocoracidae, Podicipedidae, Laridae, and Anatidae, were collected from the Iranian coast of the Caspian Sea. Samples were analyzed for organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), and seven PCB congeners. p,p'-DDE was predominantly found in all species, at concentrations ranging from the limit of quantification (LOQ) to 340 ng/g ww. Most frequently encountered PCB congeners, in all samples, were 118, 153 and 138; and birds in Phalacrocoracidae had the highest liver PCB (mean 90 +/- 32; ranging from <LOQ to 106 ng/g ww) whereas Podicipedidae had the highest OCP (mean 147 +/- 49; ranging from <LOQ to 340 ng/g ww) (P < 0.05). Differences in the diet, and migratory routes, were important species-specific factors that affected hepatic concentration of OCP and PCB in the species we studied. Range of OCP and PCB concentrations in the present study was lower than those reported for birds in other regions of the world. Hepatic PCB concentration found in our avian species was below toxic effect levels that have been previously reported in birds. To our knowledge this is the first report of persistent organochlorine pollutants in liver of birds from Iran.