In an under-the-radar release of new test results for its Gulf of Mexico oil spill workers, BP PLC is reporting potentially hazardous exposures to a now-discontinued dispersant chemical -- a substance blamed for contributing to chronic health problems after the Exxon Valdez cleanup -- among more than 20 percent of offshore responders.

BP's new summary of chemical testing, posted to its website this week after a nearly monthlong absence of new data, also makes notable revisions to the company's public characterization of the health risks facing Gulf workers. The oil giant now describes the government as a partner in developing the program for monitoring cleanup crews.

In a June 9 report on worker test results, BP confidently asserted that the health hazards of exposure to both dispersant chemicals and the components of leaking crude "are very low." In its latest summary, BP replaced those three words with an assurance that health risks "have been carefully considered in the selection of the various methods employed in addressing its spill."

The new BP summary, including results up to June 29, show a broad majority of workers testing below exposure limits set by the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH).

But the Valdez-linked chemical 2-butoxyethanol was detected at levels up to 10 parts per million (ppm) in more than 20 percent of offshore responders and 15 percent of those near shore. The NIOSH standard for 2-butoxyethanol, which lacks the force of law but is considered more health-protective than the higher OSHA limit, is 5 ppm.

Some public-health advocates pointed out that BP references the NIOSH ceiling of each chemical it tested for except 2-butoxyethanol, an ingredient in the Corexit 9527 dispersant that BP phased out after spraying it in the Gulf during the early days of the spill. "They're playing with these numbers," said Mark Catlin, a veteran industrial hygienist who has studied the worker-health fallout from the 1989 Valdez spill.

Natural Resources Defense Council Senior Scientist Gina Solomon described BP's continued offshore 2-butoxyethanol detection during the month of June as "worrisome."

"It suggests to me that there is still, clearly, a serious air-quality concern. ... [Gulf] air quality, if anything, seems to be deteriorating," Solomon said.

Hunter College toxicology professor Frank Mirer said it would be "implausible" that the ongoing detection of 2-butoxyethanol among workers could be attributable to only BP's early use of Corexit 9527.

On June 9, BP's testing summary stated: "BP has, for the very start, worked hard to ensure that the people involved in all the activities associated with the incident are protected." That sentence also appeared in this week's report, with "BP" replaced by "the Unified Area Command," the government's joint oil spill response effort.

More questions than answers

BP's latest report on worker exposures adds test results for three components of crude oil not mentioned in previous monitoring summaries: toluene, xylene and ethylbenzene. Solomon praised the company for releasing more of its data amid pressure for increased transparency from members of Congress (E&E Daily, June 15).

"I was very happy to see they have presented results for many more chemicals than they were previously," she said.

However, the company's continued use of bar graphs that encompass ranges of exposures -- without including where and under what conditions the Gulf tests are performed -- left several occupational safety experts with more questions than answers.

New York Committee for Occupational Safety and Health industrial hygienist David Newman, who served on a U.S. EPA expert panel that evaluated lingering public health risks after the Sept. 11 attacks, cautioned against focusing on worker testing data without considering broader details of particular on-the-job chemical exposures.

"We had a humongous amount of data after 9/11," Newman said. "Most if not all of the data were reassuring. And yet harm was done."

Catlin echoed Newman's warning. "There are certainly some folks saying, 'Look at all this data, everything looks good,'" he said, "but we saw that same thing on the Exxon Valdez. ... The summary data BP provides is too sketchy to be able to give a clean bill of health."

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