April 30, 2010 -- The Deepwater Horizon incident occurred about 50 miles southeast of Venice, La., on April 22 after an explosion and fire damaged a Transocean oil rig, causing it to burn for hours and sink. There were approximately 700,000 gallons of fuel onboard before the fire, and exactly how much of this fuel burned before it sank is not known, according to the National Oceanic and Atmospheric Administration (NOAA) in Silver Spring, Md.
The spill could affect hundreds of species of fish, birds, and other wildlife along the Gulf Coast, which is one of the world's richest seafood grounds. According to NOAA, there may be risks for people working as oil spill responders, observers, and in wildlife rehabilitation due to inhalation of fumes.
Oil-derived compounds including polycyclic aromatic hydrocarbons (PAHs) tend to be readily cleared from fish and mammals, so eating fish after an oil spill generally does not pose a health risk to humans. But oysters, shrimp, and crab do not readily clear PAHs and are more likely to accumulate these potentially toxic substances after oil exposure, NOAA states.
These compounds can also be toxic for fish eggs and larvae and may can cause a wide range of health problems in other marine species.
Impact on Air Quality
LuAnn White, PhD, a professor of environmental health sciences and the director of the Tulane Center for Applied Environmental Public Health in New Orleans, is on the front lines of the Deepwater Horizon oil spill.
"We are watching it very closely," she tells WebMD. "The odor from the spill could affect people with respiratory diseases such as asthma and emphysema, but the spill happened off shore, so that is good because there is no one out there," she says. The occupational health issues are immense, but proper safeguards are being taken by oil spill responders and others involved in the clean-up process, she adds.
The oil involved in the spill was sweet crude oil. "It didn't have sulfur, so it doesn't smell as bad as other types of oil and it is composed of lighter compounds that will evaporate," she explains.
So far, she says, the odor is light and transient.
There has been other reassuring news regarding air quality, White tells WebMD. "There has been air monitoring along the coastline and that didn't pick up anything so far."
Touching the oil can cause skin irritation and burning, she says. "Standing next to it and not touching it will not cause any problems."
As far as drinking water concerns, there are none. "The Gulf of Mexico is a saltwater body, not a freshwater source, so drinking water contamination is not an issue," she says.
The risk of contaminated seafood reaching consumers is also relatively low, she says. "Fisherman won't be allowed to collect seafood in any area with an oil spill, so seafood caught will come from other areas."
"Any birds that are around the oil spill are susceptible to harm because oil can coat their feathers and then they can't fly or feed," she says. "We always hear people say 'if it's hurting the birds, it is hurting me,' but this is a different phenomenon," White explains. "It is the physical effects of oil coating as opposed to the toxic effects of chemical poisoning."
In general, "most oils spills have more ecological effects than human health effects," she says.
Things may get worse before they get better, says Jonathan Erdman, an editorial meteorologist at the Weather Channel in Atlanta.
There will be several days of winds directing this oil slick toward land, he predicts. And "this is exactly what they don't need," he tells WebMD. "Basically next to a landfall, tropical storm or hurricane, this is the worst-case scenario."
"We would like to see northwest winds to keep the oil slick offshore and keep the smell away from the coast," he says. This is the opposite of what is actually occurring; southeast winds are transporting oil and odor toward the Gulf Coast.
According to what Erdman has heard from local meteorological colleagues, it is being treated like a poor air quality day in the middle of summer in Houston or Atlanta. "The message is if you are sensitive to air quality and have respiratory issues, stay indoors, keep the air conditioner on and the windows shut," he says.