By Melissa Pamer Staff Writer
Last year, a broad federal study, funded by the Montrose settlement, showed that many species of fish along the Palos Verdes Shelf remained contaminated. Advisories to anglers about limiting consumption have been in effect since 1991. Concentrations of the chemicals generally declined over the period of the study but remained high.
More than 35 years after local companies stopped dumping now-banned toxic chemicals off the Palos Verdes Peninsula, a new study shows that seals and sea lions feeding in the area have contamination levels that are "terrifyingly high," according to one environmental advocate.
The California State University, Long Beach, study found that California sea lions, Pacific harbor seals and northern elephant seals have much higher concentrations than previous data has shown for the pesticide DDT and a group of industrial compounds called PCBs.
The chemicals were dumped off San Pedro's White Point from 1947 to 1971 by Harbor Gateway-based Montrose Chemical Corp. and other companies. The ocean pollution resulted in a decadelong legal battle and, in 2001, a $140million settlement with state and federal governments.
More than 120 tons of DDT and PCBs settled on the Palos Verdes Shelf, contaminating many varieties of marine life and changing fishing habits along the coast.
The Cal State study, published this month in the scientific journal Marine Pollution Bulletin, said the contamination levels it found were among the highest ever detected worldwide for marine mammals.
"The results are extremely disturbing because the concentrations of DDT are so extremely high," said Mark Gold, executive director of Heal the Bay. "I personally have not seen values this high in any species."
Gold said the study indicates that the federal Environmental Protection Agency "urgently" needs to move forward with its delayed clean-up effort. A plan is set to be released early next year, an EPA official said.
Previous studies have looked at contaminants in sea lions and seals along the California coast, but few have focused specifically on the Palos Verdes Shelf, a DDT "hot spot."
The new study looked at 145 seals and sea lions - called pinnipeds - that were stranded on the coast of Los Angeles and Orange counties from 1994 to 2006, using tissue samples saved by marine mammal centers in San Pedro and Laguna Beach.
California sea lions had, on average, 594 parts per million of DDT and 87 parts per million for PCB. Results were much higher for Pacific harbor seals, which had a small sample size, and lower for Northern elephant seals, which typically come to the region's waters only for breeding and molting.
The pinnipeds' high body-fat content makes them particularly susceptible to the accumulation of fat-loving DDT and PCBs, as does their position higher on the food chain, said Gwen Goodmanlowe, the Cal State Long Beach lecturer who published the study with graduate student Mary Ellen Blasius.
"To me, the take-home message is that we stopped dumping this stuff 30-something years ago, and it's still causing problems," Goodmanlowe said.
"We don't know if they're dying from these (chemicals), but there is a possibility that these animals with these high levels are suspectable to other things - cancer, suppressed immune systems," she said.
During the Montrose litigation, seals and sea lions were never proved to show measurable effects from the contamination, so the species are not part of restoration plans, said David Witting, a federal fish biologist.
"There was never any doubt that there was lots of DDT in sea lions," said Witting, who helps oversee restoration programs funded by the Montrose settlement. "The question is, is it hurting them?"
That matter has never been investigated, in part because it's a difficult topic to study and it's almost impossible to isolate the effects of DDT and PCBs, Goodmanlowe said.
The effects of chemical contaminants of pinnipeds may have been ignored in part because - unlike bald eagles - sea lions and seals have seen continued population growth, Witting said.