NEW ORLEANS (AP) -- Sampling by environmental groups has found oysters contaminated with oil along the Louisiana coast befouled by the BP PLC oil spill, a finding that casts doubt on statements by state and federal officials that all seafood tested here is safe to eat.
Batches of oysters were sampled on Aug. 2 and 3 near the mouths of the Atchafalaya and Mississippi rivers and laboratory tests revealed the animals were tainted by oil, according to Wilma Subra, a well-known Louisiana chemist working for environmental groups. The oysters were obtained from a reef and an old crab trap, she said.
She said oil was found in the animals even though there was no obvious sign of oil on them. She said the oil -- which she believes comes from the BP oil spill -- at the levels found in lab tests is very unusual.
"We found oysters in the shell and they appeared to have accumulated the hydrocarbons," Subra said. "I would think that these are indications that there is contamination in the oysters and additional sampling should be performed."
The sampling was backed by the Louisiana Environmental Action Network, the Lower Mississippi Riverkeeper and the Atchafalaya Basinkeeper.
Randy Pausina, an assistant secretary at the Louisiana Department of Wildlife and Fisheries, questioned the validity of Subra's report. "Everything I have seen, everything has been clean," he said.
The Louisiana Department of Health and Hospitals says that since the April 20 Deepwater Horizon explosion the agency has found no oyster samples with high levels of oil contamination. The agency has been testing for the worst kinds of oil compounds known as polycyclic aromatic hydrocarbons, which have been linked to cancer. However, in 85 of 116 oyster samples, DHH has detected only minute amounts of PAHs, the agency data shows.
"We have not found anything at a level of concern," said Olivia Watkins, a DHH spokeswoman. "What we have found is extremely low."
Louisiana has opened some waters to oyster harvesting, but much of the state's coast remains closed to oystermen because of concerns over oil.
John Tesvich, the chairman of the Louisiana Oyster Task Force, the industry's main group, said he would not be surprised if some oysters along heavily oiled shores were contaminated.
"I think it is reasonable to believe that you can find oysters with oil on them," he said. Still, he said those areas that have been opened for oyster harvesting "have been checked extensively" and were clean.
He urged people to use caution in eating oysters in areas that have been oiled. "There are locals who will harvest them recreationally," he said. "It would be wise to look for signs of oil."
Earl Melancon Jr., an oyster biologist at Nicholls State University in Thibodaux, La., said he has been looking at oysters near the heavily oiled Grand Terre Island in Jefferson Parish and found encouraging signs.
"Right now, I'm not seeing any effects at this time," he said. "They seem to be doing fine. I'm feeling optimistic about the oysters. If (the oil) is there, it is subtle. I am not seeing any physiological stress on these oysters."
But environmentalists are not convinced.
"We started out with an open mind about this, but our members were saying there was oil in places where they (officials) said there was no oil, and there were still problems in places where they (officials) said there weren't any problems," said Marylee Orr, executive director of the Louisiana Environmental Action Network. "When we got these results back, we were surprised. There shouldn't be hydrocarbons in oysters."
Ed Cake, a Mississippi oyster biologist and consultant working with oyster farmers, said he was concerned about the future of oysters along the Gulf Coast.
"Here we are four months after the spill, and they (officials) are trying to sweep it under the carpet or disperse it and say it is over," Cake said. "As it has been with opening shrimp season and now oyster season, I think it is too soon to know how oil has affected these organisms."
His concern is that oysters are consuming oil that has been broken down into tiny droplets by chemical dispersants.
"We know biologically that oil, and especially small droplets of oil that have been dispersed, are in the same size range of particles that oysters feed on," he said. In turn, he said those microscopic amounts of oil can cause "lesions and they may lead to death or cause defects or disrupt reproduction."
Copyright 2010 The Associated Press.