Oil Spill’s Long Term Impact on Health

Don’t breathe a sigh of relief yet; the dangers from the BP Oil Spill are not over. According to BP’s website the well has been sealed, 826,988 barrels of oily liquid have been skimmed from the surface of the water and 265,450 barrels have been removed with surface burns. The spill, possibly the largest to date, caused 300 people to seek medical care due to exposure to the crude oil and the dispersants. Three fourths of these were clean-up workers. Some of crude oil’s components, also called volatile organic compounds (VOCs), are toxic to humans and can cause respiratory irritation and central nervous system depression. Many of the initial 300 who sought medical care displayed symptoms typical of acute exposure to VOCs but these reactions are temporary. Some of the lower weight VOCs, such as benzene which is known to cause leukemia, evaporate within a few hours of reaching the surface, however, another, Napthalene, evaporates more slowly. The National Toxicology Program states that Napthalene is “reasonably anticipated to cause cancer in humans” based on research studies.

A major concern, according to a commentary in the Journal of the American Medical Association, is that “Oil can also release hydrogen sulfide gas and contains traces of heavy metals, as well as nonvolatile polycyclic aromatic hydrocarbons (PAHs) that can contaminate the food chain”. Vertebrates can eventually clear these PAHs from their systems, but invertebrates cannot. This means that the chemicals will accumulate in the invertebrates and be present in oysters, shrimp and crab harvested from the Gulf. In addition:

• Very small amounts of cadmium, lead and mercury from the crude oil can accumulate in fish tissues possibly causing health hazards down the road from consumption of tuna and mackerel.
• The hydrogen sulfide gas released from the oil has been linked to acute and chronic central nervous system effects.
• The burning oil creates a “particulate matter” that can cause cardiac and respiratory problems and premature mortality.
• Skin exposure to the chemical dispersants used and the oil itself can cause dermatitis and skin irritation.

Levels of heavy metals and other toxic substances such as toluene and benzene can be tested for in your body but it will be a long time before we see the full effects of the disaster. Of the people exposed to the Exxon Valdez oil spill (1811 compensation claims were files) most suffered acute reactions to exposure, but 15% were for respiratory problems and 2% for dermatitis. There was a higher incidence of respiratory tract symptoms 2 years after exposure, as well as the possibility of genetic abnormalities and mental health effects including anxiety, posttraumatic stress, depression and psychological stress.

The National Institutes of Health has pledged at least $10 million to study the potential health impacts of the spill, tentatively named the Gulf Worker Study. One of the authors of the Journal of the American Medical Association commentary stated that research into the long term effects of this type of event has been notoriously spotty but maybe this time it will be different. According to Dale Sandler, an epidemiologist at the National Institute of Environmental Health Sciences (NIEHS), “the sweeping research project will prospectively track the health of about 50,000 adult workers and volunteers who contributed to cleaning up the oil spill. The study will include pulmonary and neurological function tests, mental health monitoring, DNA damage analyses, immunological assessments, and other screens.” The study will continue looking into the health effects of the spill and the dispersants used to clean it up but funding will also be available to provide care for those suffering harmful effects from the spill.

Physicians and health care workers need to be aware of these possible health problems and be prepared to ask the right questions: definitive exploration of symptoms, possible occupational exposure or location of residence. There are many symptoms that mimic toxicity from exposure to oil and related chemicals. Physician should focus on the skin, respiratory tract and neurological symptoms and clearly document any symptoms that might be related to oil exposure. Unfortunately, the level of care that is recommended is minimal and is simply clear documentation, removal from exposure and supportive services. Our Gulf Coast health care providers and services in Texas and Louisiana need to be ready to assist by offering appropriate testing and guiding people to the right supportive care to alleviate symptoms.