Tissue distribution of trace elements and DDE in brown pelicans

Tissues from 10 Californian brown pelicans (Pelicanus occidentalis) were analysed for trace metals, selenium and organochlorine pesticides. For each tissue, detectable concentrations of the various elements were found either in most (8-10) of the birds or in only 1 or 2 (ie seldom between the extremes). Livers contained the highest levels of copper and selenium. Kidneys contained the highest concentrations of cadmium and chromium, and bones had the highest levels of lead and zinc. Mercury levels in feathers were only slightly higher than those in liver and kidney. Arsenic occurred in the liver and kidney of one pelican, and in the liver (only) or kidney (only) of two others. Cadmium, chromium and selenium levels (dry weight basis) were higher than those reported for U.S. Atlantic coast brown pelicans, but arsenic and mercury levels were lower. All the birds contained p,p-DDE, the only organochlorine compound found at quantifiable levels. Mean concentrations in carcass homogenate, breast muscle and wing muscle were, respectively, 0.93, 0.65 and 0.19 ppm (wet weight), and 7.2, 6.0 and 5.6 ppm (lipid weight). Some correlations between data obtained in this study were evident, but sample sizes made analysis difficult.