HOUMA — Some scientists are challenging the government’s assertion that Gulf of Mexico seafood is safe after the BP oil spill.
They question whether federal agencies are properly testing for oil and whether they’re realistically estimating seafood-loving Gulf Coast residents’ risk.
A survey of Gulf Coast seafood meal habits released last week by the Natural Resources Defense Council, a national
environmental group, found that government seafood-testing programs severely underestimated local’s appetite for seafood.
That may also mean the government is underestimating locals’ risk of exposure to oil pollutants.
Consumption rates are used to set the levels of contamination that can be allowed in food before it is ruled a threat to health. The higher the consumption rate, the more toxins are consumed, so the lower the acceptable level of contamination allowed for a product to be deemed safe.
A survey of nearly 550 coastal residents in the four Gulf states by the Natural Resources Defense Council found they had seafood consumption rates far higher than those being used by federal and state regulators to determine if contamination levels pose a risk to human health.
Particularly when it came to eating shrimp, actual consumption was found to be between three to 12 times higher than the rates the U.S. Food and Drug Administration is using.
“It’s common knowledge that people in the Gulf love their seafood. Yet despite this, FDA has been setting safety standards for cancer-causing chemicals based on nationwide seafood-consumption rates, failing to take the uniqueness of the regional diet into consideration,” said Dr. Gina Solomon a senior scientist with the Natural Resources Defense Council, an environmental group.
“This is a problem, because it means that current FDA standards may also be failing to adequately protect many people in the Gulf.”
The FDA protocol is based on national seafood-consumption rates. The agency assumes that people eat two meals of fish and one meal of shrimp per week, with no more than four jumbo shrimp eaten in a sitting.
“That’s probably accurate for Minnesota but not New Orleans,” said toxicologist William Sawyer.
An FDA spokesman said when determining consumption rates for testing, the agency relied on data from the National Health and Nutrition Examination Survey.
“The FDA is not aware of any published data upon which we can rely for seafood-consumption figures other than what we used,” the spokesman said in a prepared statement. “When developing the mutually agreed upon reopening protocol, we asked state regulators in the Gulf if they had any other data sources on seafood-consumption rates, and they were not able to provide any.”
John Stein, manager of the National Oceanic and Atmospheric Administration’s seafood-safety program, added that in all the samples tested so far, levels of hydrocarbons, toxic components of oil, are “very low.” So low that increased consumption of seafood beyond the FDA rates wouldn’t pose significant health risks, he said.
Meanwhile, independent scientists are also concerned that seafood testing isn’t picking up all the oil contaminants in seafood.
Sawyer, of Sanibel, Fla.-based Toxicology Consultants and Assessment Specialists, said immediately after the release began, he and a team of scientists began collecting samples of water, sediment, tar balls and marine life from around the Gulf Coast. To date, they’ve tested about 300 samples.
He said he is concerned that the overuse of dispersant after the Deepwater Horizon spill has placed a high level of hydrocarbons from oil into the Gulf.
Sawyer found a specific type of oil compound that could build up in the flesh of marine animals and seafood. It’s a type of chemical NOAA and the FDA aren’t testing for, he said.
The federal agencies are testing for PAHs, or polycyclic aromatic hydrocarbons, he and federal officials agree.
They have relied on sensory tests — sniffing and tasting the seafood — to determine whether petroleum is present, Sawyer said.
“It assumes that there are volatile hydrocarbons with an odor present, and in many cases, those are long gone from seafood,” he said. “What we have left are hydrocarbons that have no odor.”
But Sawyer said these chemicals still pose a risk to consumers. He believes they could cause liver and kidney damage, especially to those who have underlying conditions such as hepatitis.
Sawyer said based on his findings, he would recommend that Gulf Coast residents severely limit their seafood intake.
Wilma Subra, an independent chemist from New Iberia who has being conducting seafood and soil sampling since the early days of the spill, said her tests have found high levels of organic petroleum hydrocarbons, chemicals from oil, in soils and in soft tissues of shrimp, crabs, fish and oysters.
She said she has also begun to find increasing levels of PAHs that have built up in the tissues of fish, shrimp and crabs as they feed on other oiled marine life.
Subra contends the federal government’s testing is inadequate because the safety standard doesn’t take into account the effect oil toxins could have on vulnerable populations like children, the elderly and sick people.
NOAA officials said years of research have determined that PAHs are the oil compounds of most concern to human health. That’s why they test for those rather than a gamut of other oil-related chemicals.
PAHs are potent and volatile pollutants found in oil known to cause cancer and have a toxic effect on human organs.