Arsenic in Your Drinking Water: How the Chemical Industry Influences Public Health Policy
September 22, 2014
In decisions about regulating toxic chemicals, public policy and professional norms give clear advantage to industry and its scientists. When a new pharmaceutical is proposed for sale, the Food and Drug Administration demands proof that it is safe and effective before approving it for the market. Unfortunately the Environment Protection Agency by law does just the opposite. It presumes that a chemical is safe until scientific evidence proves otherwise.
The EPA does little original research, so the burden of protecting the public falls largely on academic scientists funded by federal grants. Yet scientists doing much of the independent research on toxic chemicals typically remain detached from the regulatory process. They prefer that their scientific articles speak for themselves. Chemical companies and their scientists often take the opposite tack. They are quite active in presenting their own findings to the EPA.
Even when EPA scientists conclude that a chemical is dangerous, there can be enormous obstacles to publishing those findings. Take the example of arsenic. The last time the EPA completed a scientific assessment of this known carcinogen was in 1988. In 2009, the EPA sent a new draft assessment to the White House concluding that arsenic was 17 times more potent as a carcinogen than it had previously believed. Ideally, the EPA aims to set drinking water standards that would reduce excess cancers due to exposure to a carcinogen to one in a million. EPA scientists calculated that for people exposed daily to the current standard of arsenic in drinking water (10 parts per billion), the ratio of excess lung and bladder cancers is 7,300 in a million. Considering the exposure people get from food and unregulated private wells, millions of Americans could be at risk.
Pesticide companies that sell an arsenical herbicide hired a public-health scientist to critique the EPA's draft assessment. Among her criticisms was that the EPA had not considered 285 published articles on arsenic since 2008. The pesticide companies took this argument to members of Congress, who in a letter to then-EPA Administrator Lisa Jackson wrote, "We find that troubling and are concerned that this could allow critics to conclude that the agency is ‘cherry-picking’ data to support its conclusions."
Michael Hansen, a senior scientist at Consumers Union who has followed the arsenic review closely, said, “This is a really dishonest ... That’s because the [EPA] document was written in early 2008, and the only reason the public is seeing it [in 2010] is because OMB sat on it.”
Still, one of the letter’s authors, Rep. Mike Simpson of Idaho, used a complicated legislative maneuver to prevent the EPA from completing its assessment or taking any action based on it. Simpson instructed the EPA to turn to the National Academy of Sciences for help on a new assessment and to take into account the 300 published studies since 2008.
The new review will also consider non-cancer effects. Researchers have found associations between arsenic and strokes, heart disease and diabetes. A recently published study also found that school children in Maine who drank arsenic -- even at levels below the drinking-water standard -- scored an average of six points lower on IQ tests than children expose to little or no arsenic.[i] And there's other evidence that arsenic is an endocrine disruptor, showing effects in cell cultures and animals at levels well below 10 parts per billion.
As part of its review, the National Academy in April 2013 invited experts on arsenic to speak at a hearing. One of the speakers was Samuel Cohen, a professor of oncology at the University of Nebraska Medical Center. In his presentation, Cohen said there is a clear threshold dose below which arsenic was not harmful to humans. He said the mode of action for both cancer and non-cancer effects is the same. In an article he sent to the National Academy, Cohen concluded that there are no visible cancer effects on humans from inorganic arsenic at levels below 100 parts per billion.[ii] Cohen did not disclose during his presentation that some of his research is funded by the pesticide companies who lobbied Congress for the delay. Joseph Graziano, who chaired the hearing, later said that he did not know that any of the speakers had ties to the pesticide industry. The National Academy does not require speakers to disclose financial ties. Cohen said he discloses his ties in publications, which say that his is funded by the "Arsenic Science Task Force."
In June, the EPA started its reassessment of arsenic by holding a public “stakeholder” meeting. The agenda listed 46 presentations, 37 of which were from scientists funded by industry. Public health scientists who have done much of the significant research on arsenic were not at the meeting. Rarely do independent scientists attend such meetings or submit public comments. They often say that they don’t have the time or resources. Also, they say they don’t want to be perceived as “activists.”
Pressures from the chemical industry have been successful at reducing the volume of toxic chemical assessments from the EPA to a trickle. While there are at least 80,000 chemicals on the market, the EPA since 1996 has managed to assess an average of only five chemicals a year. The Government Accountability Office in 2008 described the EPA’s scientific assessment process as “at serious risk of becoming obsolete.”[iii]
[i] Wasserman GA(1), Liu X, Loiacono NJ, Kline J, Factor-Litvak P, van Geen A, Mey JL, Levy D, Abramson R, Schwartz A, Graziano JH, A cross-sectional study of well water arsenic and child IQ in Maine schoolchildren. Environ Health. 2014 Apr 1;13(1):23.
[ii] Cohen SM, Arnold LL, Beck BD, Lewis AS, Eldan M. Evaluation of the carcinogenicity of inorganic arsenic. Crit Rev Toxicol. 2013 Oct;43(9):711-52.
[iii] Government Accountability Office, Low Productivity and New Interagency Review Process Limit the Usefulness and Credibility of EPA's Integrated Risk Information System GAO-08-440, Mar 7, 2008.