OCEAN FLOOR CLEANER, STUDY FINDS.

Byline: David Baker Daily News Staff Writer

Although pollution still taints the ocean floor along Southern California, the coastal environment is far cleaner now than it was decades ago, according to a study released Wednesday.

The far-reaching report found healthy fish populations and generally clean water from Point Conception to the Mexican border. And even in Santa Monica Bay and other areas polluted with industrial chemicals, the level of contamination remains relatively low.

``Things tend to have improved over the last 20 years,'' said Steven Bay, a toxicologist who worked on the study. ``Overall, we're in good shape.''

Problem areas remain, however. Every sediment testing site in Santa Monica Bay showed chemical contamination, compared to 90 percent of test sites throughout the region, Bay said.

And the levels of contamination within the bay were higher than in most other areas, in some cases high enough to pose a health threat to fish, although not to humans, he said.

``Santa Monica Bay definitely had higher contamination levels than the rest of the (region),'' said Janet Hashimoto of the U.S. Environmental Protection Agency. ``The result isn't surprising considering it's a highly urbanized area.''

The EPA was just one participant in the five-year study, perhaps the largest survey ever of Southern California's coastal waters.

Combining the efforts of 15 federal, state and local agencies, the study took a snapshot of environmental conditions on the continental shelf just off the coast, with water samples collected at 271 locations and sediment collected at 261.

``The importance of this effort can not be underestimated,'' said Mark Gold, executive director of the environmental group Heal the Bay. ``This kind of regional monitoring finally gives us an accurate picture of what's going on throughout the area.''

Much of the pollution found by the survey actually entered the ocean years ago. The chemical compound DDT, banned in the 1970s because it interferes with the reproduction of fish and birds, accounts for the vast majority of contamination near Los Angeles, Bay said, mostly because it used to be manufactured in the area.

But even though DDT and other contaminants still cycle through the ocean's food chain, their levels have decreased dramatically over the years. Bottom-dwelling fish studied in the survey showed 95 percent less DDT and PCB contamination than they did 20 years ago.

A follow-up study is planned to examine the health of the region's bays, harbors and coastline, areas not covered in the current survey.