Oil Slick's Human Health Risks Small, but Concerns Linger

May 3, 2010— -- People living in the coastal areas near the massive oil slick in the Gulf of Mexico likely have little to fear in terms of health effects, environmental health specialists say -- though it is likely that the scope of the ecological disaster will still worry many.

"I think that people get afraid about health effects when these events happen, and rightfully so," said LuAnn White, director of the Center for Applied Environmental Public Health and an expert who is currently working with the Louisiana state health department to assess the effects of the spill. "But what we see from oil spills is more ecological effects than human health effects."

Still, some remain concerned over the impact that the spill could have on the safety of the seafood for which the Gulf Coast is famous.

The slick emanates from an underwater pipe fractured after a BP oil rig exploded and sunk on April 20. The U.S. Coast Guard estimates that 5,000 barrels a day are leaking from the resulting wreckage, and it is now believed that the total cost of the disaster could eclipse that incurred by the Exxon Valdez tanker spill off the coast of Alaska in 1989.

It is not the first time Louisiana has encountered an oil spill; in 2005, Hurricane Katrina dislodged a 250,000-barrel storage tank near New Orleans, which subsequently released oil into several residential areas. At that time, public health experts feared that residents could be exposed to gases called volatile compounds that emanate from oil and can be toxic and cancer-causing.

White said, however, that the fact that this spill is far from shore makes it highly unlikely that those on shore will be exposed to these gases.

Oil Spill's Toxic Fumes Far From Shore, Experts Say

"This is happening in the middle of the Gulf, where there is nobody around," she said, adding that thus far, tests by the Environmental Protection Agency have turned up no evidence of dangerous airborne chemicals in coastal areas from the spill.

Dr. Philip Landrigan, director of the Children's Environmental Health Center at the Mount Sinai School of Medicine in New York, said that in addition to exposure to volatile compounds the health considerations that come along with an oil spill include skin rashes from direct contact with the oil, as well as the risk of ingesting the oil -- a risk he said is "probably greatest for small children who might intentionally or inadvertently swallow some of the oil."

But Dr. Marcel Casavant, chief of Pharmacology and Toxicology at Nationwide Children's Hospital in Columbus, Ohio, said most will not be in situations in which they will be exposed to these dangers. The exception, he said, could be those who will be working to clean up the mess.

"People who have to work in this environment are likely to have bigger exposures and do have higher risks," he said. "Because the hazards are real and this training and protection are so important, those of us who aren't working with the spill or volunteers working with a group formally designated to help with rescue and cleanup should just stay away."

Meanwhile, one method that the U.S. Coast Guard has adopted to diminish the slick has been to burn off some of it -- an approach that has also released large amounts of smoke into the atmosphere.

"Smoke from burning oil contains many chemicals; some are potentially-lethal poisons and some are nuisance irritants, but even these nuisance irritants can trigger breathing problems in people with asthma or emphysema or other lung disease," Casavant said. "The good news is that the further we are from the fire, the less dangerous is the smoke that reaches us, and the more likely that we'll have no symptoms or only just irritation -- runny itchy or burning eyes, scratchy or sore throat, or minor cough."

Thus far, White said, the smoke released from these efforts has not reached shore. "If they will do more burning, certainly we will watch to see where that smoke goes," she said.

Could Oil Spill Effects Linger in Seafood?

The oil slick is almost certain to have a devastating impact on the seafood industry in the Gulf of Mexico -- a region from which 20 percent of all seafood in the U.S. originates. Environmental experts already expect harvests to be decimated, and many shrimpers have begun the shrimp season early in order to get to the seafood before the slick does.

The possibility of human illness from seafood contamination is of the chief concerns that White has heard from many people so far has been. But she said that even though the oil spill will have a huge effect on the industry, she does not believe the situation presents an immediate threat to those who consume seafood.

"There is not going to be fishing or shrimping in the area where the spill is, and there will probably not be much fish or shrimp in these areas currently," she said. White also said that unlike other chemicals, such as heavy metals and BPA, the chemicals that make up crude oil "usually do not bioaccumulate" -- that is, they do not linger in the tissues of animals and build up to a degree that they become toxic.

But Casavant said the potential for contamination still exists.

"Fish and seafood can be contaminated by the spilled oil," Casavant said. "Of those fish and seafood that survive, the main risk public health authorities worry about will be cancer.

"It's not that eating a contaminated shrimp or mussel causes cancer, but eating various amounts of some of the components of the oil increases one's chances of getting cancer."

For this reason, he said, it will be up to environmental agencies to be on the lookout for these chemicals -- possibly for years to come.

"Testing is needed; careful, repeated testing of both the water and the organisms," he said. "And from that testing the public health and fisheries authorities will make determinations of when it's acceptable to take which species from which areas."