Send to

Choose Destination
Mar Pollut Bull. 2005 Jan;50(1):30-9.

The role of organochlorines in cancer-associated mortality in California sea lions (Zalophus californianus).

Author information

Environmental Conservation Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA 98112, USA.


Wild California sea lions (Zalophus californianus) have an unusually high prevalence of neoplasms (18% of stranded dead adults) and high levels of contaminants. The contribution of organochlorine (OC) tissue burdens to the probability of sea lions dying from carcinoma was explored using a logistic regression model. Levels of PCBs and DDTs were determined in blubber of sea lions diagnosed with metastatic carcinoma and animals that had died from non-carcinoma-related incidents (e.g., gunshot, domoic acid poisoning). Animals with carcinoma had higher mean concentrations (based on wet weight) of PCBs and DDTs (more than 85% and 30% higher, respectively) in blubber than did sea lions without carcinoma; the highest concentrations of OCs in the sea lions affected with carcinoma were measured in the males. Blubber thickness was significantly different between the two groups of sea lions, but after controlling for this difference, there was still a significant effect of PCBs, but not DDTs, on the probability of sea lions dying with carcinoma. Age, sex, mass and length did not affect the probability of dying from carcinoma.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center