Workers who cleaned up the 2010 Deepwater Horizon oil spill in the Gulf of Mexico were more likely than others to have developed asthma or related symptoms, a long-term follow-up shows.
"This is the first study to ever look at specific chemicals from oil spills and link them to respiratory diseases," said study co-author Dale Sandler, of the U.S. National Institute of Environmental Health Sciences (NIEHS).
"If you were an oil spill cleanup worker in the gulf experiencing wheezing or other asthma-like symptoms, it would be good to let your health care provider know you worked on the oil spill," Sandler said in an agency news release.
BP's Deepwater Horizon spill was the largest marine oil spill in U.S. history. The Gulf Long-Term Follow-up Study, or GuLF, found workers on the cleanup site were 60% more likely to be diagnosed with asthma or experience wheezing symptoms. Researchers analyzed data from more than 19,000 spill response and cleanup workers and 5,585 others who were trained but not part of the cleanup.
None had been diagnosed with asthma prior to their work.
About 5% of the cleanup workers (983) reported asthma and asthma symptoms, while 3% of nonworkers had symptoms. The reports included asthma diagnosed by a doctor or self-reported by participants who had never smoked but had wheezing or whistling in the chest all or most of the time.
"Because the GuLF STUDY population is socioeconomically vulnerable, with less than half reporting access to medical care, we included non-doctor confirmed asthma cases to minimize any underreporting of true asthma cases in the population that would be missed due to lack of access to health care," Sandler said.
Some of the chemicals encountered during the Deepwater cleanup are classified as hazardous by the U.S. Clean Air Act.
As part of the study, researchers estimated workers' exposure to specific chemicals. They also looked at the relationship between asthma or related symptoms and the types of jobs cleanup workers held, as well as their exposure to total hydrocarbons.
Researchers then explored links with a subgroup of chemicals in crude oil, including benzene, toluene, ethylbenzene, xylene and n-hexane. Collectively, these are known as BTEX-H and are linked to other health effects in the GuLF study.
As participants' exposure to BTEX-H chemicals rose so did their relative risk for respiratory symptoms, according to the study.
The study included people who mopped up crude oil aboard a sea or shoreline vessel, decontaminated wildlife, did environmental water sampling and provided administrative support. Those who operated, maintained or refueled the heavy cleanup equipment had the highest rates of asthma.
"The more a worker was exposed to these crude oil chemicals, including total hydrocarbons, the individual BTEX-H chemicals, and the BTEX-H mixture, the more likely they were to have asthma symptoms," said lead author Kaitlyn Lawrence, a staff scientist in the NIEHS Epidemiology Branch. "Exposure levels varied depending on the person's cleanup jobs and how long they worked."
The study, published in the September issue of the journal Environment International, is the largest on the health of workers who responded to the spill.
The U.S. Centers for Disease Control and Prevention has more on asthma.
SOURCE: U.S. National Institute of Environmental Health Sciences, news release, Aug. 17, 2022