Oil Spills, Health Effects of

Along with fouling marine and coastal ecosystems, offshore oil spills pose potential health hazards for humans, both as workers respond to spills and as oil impacts the environments where people live. After the 1989 Exxon Valdez oil spill that occurred in Prince William Sound off the coast of Alaska, one study published in the American Journal of Psychiatry showed that residents living in areas affected by the spill were more likely to suffer mental health problems than the general population, even years after the spill. (Few studies were conducted, however, on the health impacts of workers who were exposed to the oil during clean-up efforts.) In the wake of the 2010 BP (formerly British Petroleum) Deepwater Horizon oil spill in the Gulf of Mexico, information remains inconclusive on the actual human health hazards that could derive from the spill.

At a gathering of public health experts in late June 2010, U.S. surgeon general Regina Benjamin (1956–) noted some scientists' predictions that little or no toxic effects would result from short-term exposure to the oil, while indicating that “other scientists express serious concerns about the potential short-term and long-term impacts the exposure to oil and dispersants could have on the health of responders and [the local] communities.” However, near the end of April 2011, the U.S. National Institutes of Health (NIH) began what was called a “massive, long-range health study” of the workers and volunteers who helped clean up the Gulf oil spill. Without clear medical indications concerning the long-term health consequences of about 55,000 workers and volunteers in Alabama, Florida, Louisiana, and Mississippi, the study intended to examine many of these people for ten years, looking for possible mental and physical health problems from their direct participation in the cleanup of Gulf of Mexico oil spill.

Virtually everyone who lives near a coastline could be affected by an oil spill, as more than 38,000 oil tankers traverse the world's oceans and seas, delivering oil in its various stages from ports near the extraction site to ports where it is refined and later consumed. Offshore drilling fields are located primarily in the North Sea, the Gulf of Mexico, the South China Sea, and off the coasts of Nigeria, Angola, Brazil, the Canadian provinces of Nova Scotia and Newfoundland, and eastern Russia. Large land-based oil fields are located in the Middle East, the United States, Russia, Mexico, and Venezuela. Persons especially at risk to the potentially harmful effects of oil exposure include those with existing respiratory problems, pregnant women, and children. Potential adverse health problems for such people include respiratory ailments, such as those associated with the lower respiratory tract, and nausea. Developing fetuses and small children may also develop neurological problems and hereditary mutations.

Although its composition varies somewhat depending on its source, crude oil is a naturally occurring brown or black liquid that is composed of a mixture of hydrocarbons and other organic compounds. Crude oil is toxic, flammable, and contains volatile organic compounds (VOCs) that have known adverse effects on human health, such as benzene (a carcinogen) and polycyclic aromatic hydrocarbons (PACs), which are toxic to the central nervous system. VOCs evaporate easily, moving from the oil into the air, and can be carried by prevailing winds miles from the source of a spill and into coastal communities. There is evidence that some dispersants, solvents, and collecting agents used to manage the spill can enhance some of the toxic effects of crude oil alone. Harmful airborne pollution released by burning the oil on the surface of a spill is also a health concern for both responders and local on-shore populations.

Hundreds of workers cleaning Alaskan shores, marshes, and oiled waterways after the Exxon Valdez spill complained of skin rashes, dizziness, headaches, and nausea during their work and for a short time afterward. Some experienced longer-lasting symptoms, including shortness of breath, muscle aches, and neurological problems, such as numbness and tingling of the extremities.

Public health officials along the Gulf Coast are monitoring for these symptoms in communities affected by the Deepwater Horizon spill, as well as establishing data-collection methods to document possible longer-term consequences of oil exposure, such as kidney damage, birth defects, and cancer. As of 2012, complaints among coastal residents, along with workers cleaning the oil both on land and at sea, included skin rashes, headaches, nausea, and irritation in the throat and eyes. Several workers also experienced heat stress due to working in hot and humid weather.

Although high levels of mental and emotional stress are expected during a natural or technological disaster, the Deepwater Horizon oil spill impacted an area whose vulnerable population was still recovering from hurricanes Ivan, Katrina, and Rita. Benjamin Springgate, a physician and public health researcher at Tulane University in New Orleans, Louisiana, estimated that over 30% of people in the impact zone of Hurricane Katrina experienced symptoms of anxiety, depression, or other mental illness after the storm, and also predicted that the impacts of the Deepwater Horizon oil spill on the mental health of coastal residents will be long term. The most frequent symptoms of stress-related mental disorders include feelings of hopelessness, disturbances in sleep patterns, lack of concentration, mood swings, irritability, inability to make productive decisions, nightmares or persistent memories of disturbing or frightening events, and general anxiety.

The most frequent mental disorders diagnosed among people affected by an oil spill include posttraumatic stress syndrome, anxiety disorders, and depression. A psychiatrist or other mental health professional diagnoses these disorders, mostly after a careful discussion of the symptoms. Other oil-spill-related illnesses are diagnosed according to the nature of symptoms, physical examination, and additional diagnostic or laboratory tests. For example, respiratory irritation from exposure to VOCs or other chemicals, followed by inflammation and decreased lung function, causes chemical pneumonia. It is most often diagnosed by history and physical examination, especially auscultation of (listening to) the lungs, examination of the sputum, and x rays, as are other types of pneumonia.

The full effects of the Deepwater Horizon oil spill on the health and well-being of people living in communities along the northern Gulf of Mexico was not anticipated to be fully known until the oil was cleaned and the physical, ecological, and economic environments were restored, a process that was expected to take years. Scientists anticipated that the information gained from careful study of the detrimental effects of the oil spill on the physical and mental health of spill responders and Gulf coast residents would help identify both short- and long-term health issues related to the spill and allow for an effective response now and during future technological disasters.

Avoiding contact with the oil is the most effective way to prevent negative health effects from an oil spill. Beaches along the northern Gulf Coast had no swimming signs and flags posted in locations where oil from the Deepwater Horizon spill had affected the shore. Workers both offshore and at the spill site used a variety of personal protective equipment, including gloves, white plastic protective (hazmat) suits, respirators, and other barrier methods designed to prevent exposure to oil. (Hazmat is short for hazardous materials.)

When winds bring onshore fumes from the spill, residents with existing respiratory problems are advised to remain indoors with recirculating air. Pregnant women should avoid oil-contaminated beaches and air, as components of crude oil are known teratogens and exposure to crude oil can result in decreased fetal survival. Children are also particularly vulnerable to DNA (deoxyribonucleic acid) damage from long-term exposure to airborne toxins emanating from oil spills. The U.S. Environmental Protection Agency set up more than 100 monitoring stations along affected areas of the Gulf Coast to detect unhealthy levels of VOCs, overall ozone, and particulate matter in the air and to issue regular air quality reports.

Innovative approaches were taken along the Gulf Coast to reach people who might be experiencing symptoms of stress but were unlikely to seek help. Peer listeners were trained to identify signs of distress during conversation, to offer encouragement that help is available, and to provide referrals to nearby mental health services. Personnel with knowledge of and sensitivities to local cultures, including those who speak Vietnamese and Spanish, were also made available to hear the needs and concerns of fishermen and other close-knit communities.

See also Exxon Valdez; Gulf oil spill; Ozone.

Brenda Wilmoth Lerner, RN