A Feb. 24 article about industry-funded scientists who withheld data about the toxicity of hexavalent chromium referred incorrectly to a Baltimore study of chromium workers. The study involved about 70,000 person-years of data, not 70,000 people.
Chromium Evidence Buried, Report Says
Friday, February 24, 2006
Scientists working for the chromium industry withheld data about the metal's health risks while the industry campaigned to block strict new limits on the cancer-causing chemical, according to a scientific journal report published yesterday.
The allegations, by researchers at George Washington University and the Washington-based Public Citizen Health Research Group, are based on secret industry documents obtained by the authors.
They come just days before the Occupational Safety and Health Administration is to announce its new standard for workplace exposure to hexavalent chromium -- a known carcinogen handled by 380,000 U.S. workers in the steel, aerospace, electroplating and other industries.
Documents in the report, published in the peer-reviewed online journal Environmental Health, show that the industry conducted a pivotal study that found a fivefold increase in lung cancer deaths from moderate exposures to chromium but never published the results or gave them to OSHA. Company-sponsored scientists later reworked the data in a way that made the risk disappear.
OSHA has not said what the new limit will be. But sources close to the agency have been told to expect a standard that would allow five times more exposure than it had initially proposed -- a shift that would be a victory for the industry, saving it billions of dollars in upgrades and plant closures.
Company representatives and the contract scientist who led the reworked analysis denied any wrongdoing.
"The idea that there was a conspiracy here . . . is completely and utterly false," said Kate McMahon-Lohrer, a lawyer at Collier Shannon and counsel to the Chromium Coalition, an industry group that has worked for a decade to forestall tighter regulation.
But David Michaels, director of the project on scientific knowledge and public policy at GWU's School of Public Health and a senior author of the report, compared the industry's behavior to that of tobacco and pharmaceutical companies that were found to have withheld damning evidence of risks associated with their products.
"Participants in proceedings before OSHA and other regulatory agencies should be required to provide all relevant data," Michaels said.
Scientists have known for decades that inhaled particles of hexavalent chromium, or "chromium VI" -- made notorious in the movie "Erin Brockovich" -- can cause lung cancer. But exposure limits for workers have not changed since 1943, when the metal dust was considered a mere skin irritant.
In 1993, Public Citizen petitioned OSHA to set a new standard. Nine years and two lawsuits later, a federal court ordered OSHA to do so by January 2006 (later extended to Feb. 28).
The decades-old "permissible exposure level" is 52 micrograms per cubic meter of air. On the basis of the few large studies done in recent years, advocates sought a new level of 0.25 micrograms. In 2004, OSHA released a proposed limit of 1 microgram.