Lawsuits are already being prepared alleging harm to people who are living near or working to clean up the Deepwater Horizon oil spill off the coast of Louisiana. The law firm Smith Stag in New Orleans says it has assembled a group of lawyers in the Gulf states to process such claims.
Stuart Smith, a partner in the firm, says he has been in touch with people in Alaska who say they were hurt during the Exxon Valdez spill in 1989 by chemicals in the oil and dispersants used to keep it from reaching shore "which are also toxic." He says he's concerned about the potential health effects on the thousands of out-of-work fishermen, shrimpers and oystermen who will be taking part in the cleanup in the Gulf of Mexico.
So what are the human health risks from a disaster such as this?
LuAnn White, a toxicologist and director of Tulane University's Center for Applied Environmental Public Health, doesn't believe there's much danger to people, especially those on the coast or inland.
"Oil spills are ecological events, not human health events," she says. The most dangerous gases that come off the hydrocarbons in crude oil, benzene and toluene, will disperse as they come up through 5,000 feet of ocean water and then into the air, she says. And as the entire event "is happening in the middle of the Gulf of Mexico," they won't have much effect on people on land.
Benzene is a known carcinogen in humans, according to the Centers for Disease Control and Prevention.
As for workers trying to clean the spill and cap the well, if they follow standard procedures "chances are when they load up the diesel on their boats they're getting a higher dose" of hydrocarbons, which can cause lung irritation, than from the spilled oil, she says.
Others disagree. Riki Ott, a marine biologist and activist from Cordova, Alaska, who has written two books about the Exxon Valdez spill, says there were 6,722 cases of upper-respiratory illness among workers who helped clean up.
A study done by the Korea Centers for Disease Control and Prevention found that residents exposed to oil from the 2007 sinking of the Hebei Spirit oil tanker off the Korean coast had increased risks of headache, nausea, dizziness, fatigue, tingling of limbs, sore throat, cough, runny nose, shortness of breath, itchy skin, rash and sore eyes.
Jeffrey Short, a scientist with the ocean conservation group Oceana, says in previous spills, especially Exxon Valdez, that was a danger during the shoreline cleanup phase.
There isn't much scientific literature on the topic in part because "the people who got sickest and won against Exxon got settlements that required that the records be sealed. But there were a lot of anecdotal complaints about the impact on cleanup workers," says Short, who was lead chemist for the National Oceanic and Atmospheric Administration on the damage assessment at the Exxon spill.
Another issue relates to the chemical dispersants being injected underwater near the leaks in an attempt to break up the oil and keep it from floating toward beaches where it could do more damage. More than 156,000 gallons of dispersant have been used on the spill.
The dispersants reduce surface tension so the oil breaks into fine droplets instead of being a sheet on the water surface. The potential human hazard for the two dispersants being used to break up the oil is rated high for one of them, moderate for another, according to the Material Data Safety Sheets posted on the government's Deepwater Horizon Response website.
The biggest issue for people on shore will be coming into direct contact with globs of the "mousse," as the heavier elements of the oil whipped up by wind and wave action are called because of their resemblance to the chocolate dessert.
Eventually, the weathering process -- decomposition, evaporation and dissolution -- turns them "into a fairly hard, asphalt-like substance fairly quickly" which makes any toxic substances that might be trapped in it relatively inert, Short says.
"You wouldn't want to eat" these tar balls, but they're not considered dangerous, Short says. The beaches in Santa Barbara, Calif., site of a 1969 spill, "have tar balls all over them to this day," he says.
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