Contrary to claims by some, offshore crews involved in the cleanup of BP’s massive oil spill last year were not exposed to harmful levels of toxins in the air as millions of gallons of crude gushed into the Gulf of Mexico, an independent scientific study found.
Levels of dangerous compounds associated with oil, including benzene, fell well below federally allowed limits, according to the analysis by San Francisco-based ChemRisk of nearly 5,000 air samples taken by BP near the Macondo well site in the weeks and months following the deadly blowout.
The report, published Friday in Environmental Science and Technology, a scientific journal, found that the measurements for benzene were 32-fold lower than federal limits, while toluene was 510-fold lower, ethylbenzene was 360-fold lower and xylene was 77-fold lower.
It also found no significant difference in the levels of the compounds present in the air before compared with after the Macondo well was capped on July 15, which the firm said suggests engine exhaust from vessels involved in the cleanup could be more to blame than the oil.
ChemRisk used data made public by BP for the study but was not paid by the company for the analysis.
The findings are consistent with results of smaller-scale studies by an arm of the Occupational Safety and Health Administration and the Department of the Interior, and should lay to rest claims by cleanup workers that they were exposed to dangerous levels of cancer-causing benzene, Dennis Paustenbach, president of ChemRisk and a co-author of the study, said in an interview.
“You’d be getting far more benzene when you’re filling up your gas tank,” he said.
Tom Mueller, a BP spokesman, said “extensive” worker monitoring by multiple parties from the beginning of the response have shown consistently low exposure levels, which the ChemRisk study has again confirmed.
“BP is looking forward to seeing more exposure studies published in the peer-reviewed scientific literature,” he said.
Some of the offshore workers involved in the sweeping Gulf cleanup effort have filed lawsuits against BP after experiencing nausea, dizziness, vomiting and headaches during shifts. Speculation of possible benzene exposure has swirled ever since.
High exposure to elevated levels of benzene may cause bone marrow damage and lead to increased risk of developing acute myeloid leukemia.
But scientists with ChemRisk said symptoms experienced by the workers could be explained by heat exhaustion, stress, sea sickness, dehydration or other sickness.