Swordfish, mackerel and other commercial fish purchased from selected Los Angeles-area markets have been found to have levels of toxic contamination comparable to those in some sport fish cited last year in public health warnings to pier fishermen, according to a pilot study released Monday in Santa Monica.
The study, by a team of Loma Linda University research associates, was described as the first attempt to determine whether fish sold in Los Angeles-area stores and distributed nationally contain the same high levels of DDT and PCBs--two powerful carcinogens--as sport fish identified by earlier scientific studies.
The findings, which are considered preliminary, were outlined during a congressional subcommittee hearing chaired by Rep. Henry Waxman (D-Los Angeles) to study pollution in Santa Monica Bay.
David Steinman, a journalist who organized the three-member research group, said the preliminary study was based on laboratory analyses of more than 100 fish--including white croaker, cod, rockfish, ocean perch, swordfish, shark, barracuda and mackerel--purchased from fresh-fish markets in Redondo Beach, Westchester, Koreatown, Marina del Rey and Long Beach.
Although it is impossible to know the exact origin of the fish, he said, most were identified as species indigenous to the California coastline. In addition, proprietors at several of the markets assured him the fish were caught locally, making him "reasonably sure these were . . . all (caught) within the Southern California region," Steinman said.
Steinman, who organized a pilot study released last September showing elevated blood-levels of DDT and PCBs among Los Angeles-area sport fishermen, said the newly completed study found significant levels of the two compounds in each commercial fish that was tested. (The federal safety standard for PCB and DDT in fish is 5 parts per million, although many scientists say that standard is not stringent enough.)
The white croaker bought in the markets, for example, contained 2.3 parts per million of DDT, an amount comparable to levels cited in samples of white croaker taken last year from local piers. Levels reported last April by health officials ranged from 7.6 parts per million off the Palos Verdes coast to 1.7 parts per million at the Cabrillo Pier in Los Angeles Harbor, a location cited in public health warnings.
Another commercial fish, rockfish, was found to have DDT levels of .825 parts per million, about four times the levels identified in rockfish caught by sport fisherman in Santa Monica Bay, Steinman said in an interview.
PCB levels were studied for the first time in commercial swordfish (.180 parts per million), mackerel (.112) and barracuda (.115), Steinman said. He said those levels were comparable to the levels reported in pier-caught white croaker, whose PCB levels ranged from .42 parts per million at the Gerald Desmond Bridge in Long Beach to .18 parts per million at Cabrillo Pier.
In testimony before a panel of scientists and legislators, Steinman described the overall contamination levels as comparable to those found in sport fish and said his findings would seem to refute the belief that commercial fish contain far less contamination than sport fish caught from piers or near-shore boats.
"For anybody who thinks the white croaker are any different in markets than they are (from) the piers, that's nonsense," Steinman testified.
But the report drew skepticism from Frank Iacono, general manager of the Fishermen's Cooperative Assn., a trade group representing 27 commercial vessels in San Pedro.
Iacono, contacted following the hearing, said swordfish identified as whole fresh fish by some markets may be imported from as far away as Hawaii or the East Coast. "That kind of fish comes from all over the country," he said.
Barracuda and mackerel are migratory fish that may have fed anywhere along a vast stretch of the California coastline, he said.
"Maybe some that (researchers sampled) happened to stay in one little area that was polluted," Iacono said. "I think . . . mackerel migrate all the way from Mexico up past San Francisco."
Federal and state officials who appeared at Monday's hearing, including Dr. Alex Kelter, chief of Environmental Health Hazard Assessment for the state Department of Health Services, agreed that little is known about toxic pollution in commercial fish.
Under questioning by Waxman and Rep. Mel Levine (D-Santa Monica), who requested the subcommittee hearing, Kelter said questions raised by the pilot study would be addressed as part of a $1-million fish study now being planned by the state.
If the results of the pilot study are confirmed, Kelter said, the state could consider restricting some areas from commercial fishing or removing some fish from market shelves.
Steinman said the study team included John Ljubenkov, a private marine consultant based in San Pedro, and Dr. Gary Wikholm, a physician working in his last year of residency at the Glendale Family Medicine Center.