Countywide : DDT Levels Prompt New Health Questions

High levels of DDT compounds found in Orange County soil samples pose “no immediate public health threat whatsoever,” an official of the California Regional Water Quality Control Board said Tuesday.

But Joanne E. Schneider, environmental specialist for the board, said a 32-county state survey released Monday that found the banned pesticide persisting in agricultural soils does raise questions about its potential harm to small fish and animals.

Schneider said she is asking state health officials to include Newport Bay in a major study of toxic substances in sport fish caught along the coast of Orange and Los Angeles counties. Mussels transplanted in Newport Bay in 1983-84 were found to have the highest levels of DDT ever recorded in the state Mussel Watch program.

“The concern we would have is whether there is any impact on fish and wildlife associated with high levels of DDT found in soil,” Schneider said of the Food and Agriculture Department report.

Results of both the Mussel Watch program, the state’s toxic substances monitoring program for bait fish, and the regional board’s own study of sediment in the bay’s network of upstream tributaries have already documented higher-than-expected concentrations of DDT.

What health and environmental officials do not know, Schneider said, is the level of toxics accumulating in larger fish in the bay’s food chain, and the potential impact on humans who eat those fish.

The regional board and county health officials already have succeeded in persuading the state Department of Health Services to add Orange County’s coast to a study of toxic substances in sport fish off Los Angeles County.

Schneider said they are now lobbying to add Newport Bay to the study area.

“The idea is to collect a sufficient data base to allow epidemiologists to calculate the public health risk of eating certain types of fish,” she said.