The Oil Spill and Human Health: More Questions Than Answers

When BP's (BP) Deepwater Horizon drilling rig exploded on April 20, killing 11 of its crew and causing a massive oil spill in the Gulf of Mexico, few imagined that more than two months later it would still be spewing an estimated 35,000 to 60,000 barrels of oil a day, causing the U.S.'s worst-ever environmental disaster.

With the undersea well still gushing oil and cleanup efforts barely making a dent, questions abound about the spill's short- and long-term effects on the environment and human health. In fact, very little is known about the health effects of oil spills as only seven spills have been studied of the hundreds around the world.

Cleanup Crews Experiencing Acute Symptoms

From the few studies of past spills, one of them by the National Institute for Occupational Safety and Health (NIOSH) after the Exxon Valdez spill, certain acute symptoms were expected, and already Gulf residents and cleanup workers are experiencing them: headaches, nausea, vomiting, diarrhea, throat irritation, eye pain, coughing or choking and dizziness.

Of greater concern is a more recent study of those exposed in Spain after the 2002 Prestige oil tanker spill, which found an increase in DNA damage. Other potential long-term risks include lung, kidney and liver damage.

With the temperature in the Gulf of Mexico hovering around 110 degrees Fahrenheit during the summer, one of the main short-term health concerns is heat exhaustion, especially among workers on the open sea.

Because so little is known about the long-term health effects of direct exposure to petroleum, the Department of Health and Human Service has set aside $10 million to track oil spill-related illnesses in states along the Gulf Coast and study cleanup workers. It asked the Institute of Medicine to host a workshop last week in New Orleans on the issue.

Crews Exposed to Fumes and Direct Contact

As of Friday, 453 oil exposure complaints had been reported to the American Association of Poison Control Centers. Of the total, 174 calls came from Louisiana, 111 from Florida, 95 from Alabama, and 38 from Mississippi. The reports so far were mostly related to odors or fumes, and mainly among those involved in the cleanup, because they have the most direct exposure to the oil.

Most exposure of Gulf residents and cleanup workers has been via inhalation, though skin contact is also common.

Volunteers among the cleanup workers are at the highest risk, because many lack extensive training in these types of hazards. The U.S. National Guard deployed 17,000 members to help with the cleanup effort. In total, nearly 35,000 cleanup workers are involved, some of whom agreed to be tracked by NIOSH.

Dispersants Inhaled Deep into the Lungs

Some of the spilled oil evaporates into the air and creates a heavy vapor that stays near the ground -- in the human breathing zone, writes Gina Solomon, a senior scientist at the Natural Resources Defense Council. "When winds whip up oily sea water, the spray contains tiny droplets of oil, which are small enough to be inhaled deep into the lungs." Aah -- oil-scented rain.

The EPA is monitoring the air on the Gulf coastline. It "has observed odor-causing pollutants associated with oil on the shore in the Gulf region at low levels. Some of these chemicals may cause short-lived effects like headache; eye, nose and throat irritation; or nausea." The EPA lists the odors in the air of the Gulf.

It appears that so far benzene and naphthalene aren't a major cause for concern, Solomon adds, but "the levels of hydrogen sulfide EPA is reporting in some areas could cause short-term symptoms in sensitive people and could potentially pose a long-term risk if the elevated levels continue."

"As for dispersants," Linda Greer, director of the Health and Environment program at the NRDC writes, "the questions that linger include how dangerous the dispersants are and whether exposure to the chemicals could cause cancer."

Toll on Emotional Health as Well

Another concern has come to the nation's attention with the suicide of William Allen Kruse, the 55-year-old fishing boat captain who helped in the Gulf cleanup effort after losing his livelihood. Doctors say that the short-term effects of the devastation of the Gulf environment and economy will include depression and psychological stress, raising suicide risk among those affected. Social workers in the Gulf region say that they are seeing a rising number of mental health problems.

And because the spill will continue for weeks or months to come and many of its effects haven't yet manifest, experts say it's impossible to tell what the overall health impact will be.

There are far more questions than answers at this stage, and the unknowns are great -- especially health-cost estimates. The full scale of the impact of the largest U.S. oil spill on our environment and health is yet to be grasped, much less measured.