by Marla Cone
Editor in Chief
Environmental Health News
December 3, 2008
Warning that “decision-making gridlock” has bogged down efforts to protect public health, a national panel of scientists recommended Wednesday that the U.S. Environmental Protection Agency overhaul its strategy for analyzing the hazards of toxic chemicals and pollutants.
Risk assessment is the scientific tool that policymakers use to guide their decisions about how and when to regulate chemicals in air, water, food and consumer products. But the assessments, often decades-long and cumbersome, fail to provide the answers that policymakers need to make their decisions, according to a panel of experts convened by the National Academy of Sciences
The reforms proposed by the committee would be the first major overhaul of the federal agency's framework for analyzing environmental risks in 25 years. Policy experts, environmentalists and others have complained for years that the EPA has been stricken with “paralysis by analysis.”
“Risk assessment is at a crossroads, and its credibility is being challenged,” wrote the National Research Council panel
, which was chaired by Thomas Burke, an associate dean and professor of health policy at the Johns Hopkins Bloomberg School of Public Health in Baltimore.
Noting that the EPA's risk reports are "subject to considerable scientific, political and public scrutiny," the scientists recommended a series of changes at EPA that they described as "more coherent, consistent and transparent."
"Global impacts are combining with the high financial and political stakes of risk management to place an unprecedented pressure on risk assessors in EPA. But risk assessment remains essential to the agency's mission to ensure protection of public health and the environment. Much work is needed to improve the scientific status, utility, and public credibility of risk assessment," the 15 scientists wrote in their report, entitled "Science and Decisions."
The problems, they said, include "long delays in completing complex risk assessments, some of which take decades to complete; lack of data, which leads to important uncertainty in risk assessments; and the need for risk assessment of many unevaluated chemicals in the marketplace and emerging agents."
The committee was convened at the request of the EPA in an effort to update its strategy, which was modeled after a 1983 National Research Council report, dubbed “the Red Book.” The experts spent 18 months reviewing EPA’s risk assessments and nearly a year preparing the 382-page report.
Top officials from EPA's National Center for Environmental Assessment were briefed Tuesday on the committee's findings, and observers said they seemed supportive of the recommendations.
EPA spokeswoman Suzanne Ackerman said the agency welcomed the report "because of our commitment to providing the best possible risk assessments to protect human health." Agency officials had no specific comments about the recommendations, but Ackerman said they will review them and then develop a plan for implementing them.
The new approach would require a major transformation at the EPA, as well as substantial commitments by the President and Congress, the panel reported.
The federal agency, according to the committee's report, “is struggling to keep up with demands for hazard and dose-response information but is challenged by a lack of resources, including funding and trained staff.”
Lacking clear and timely risk reports from scientists, policymakers cannot readily write rules necessary to protect the public and ecosystems from hazardous chemicals and contaminants.
“The regulatory risk assessment process is bogged down; major risk assessments for some chemicals take more than 10 years,” the scientists wrote in their report.
For example, in the case of trichloroethylene, a cancer-causing solvent contaminating many water supplies, the EPA has been assessing its dangers since the 1980s. Analyses of dioxin and formaldehyde also have lasted for several decades.
For other chemicals, including perchlorate and arsenic, two contaminants in water supplies, the EPA’s risk conclusions have been disputed and interpreted in many different ways, leading to controversial regulatory decisions.
Dr. Richard Jackson, a pediatrician and chair of environmental health sciences at UCLA's School of Public Health, said he is troubled that "the immensity of new science has swamped our ability to interpret it all and turn it into sensible and health protective policy." The existing system, he said, "is just not working and is not protective, especially for children."
Carl Cranor, a philosophy professor at University of California, Riverside who specializes in toxic substances policy, agreed, saying that the new report contains many good recommendations.
“They correctly recognize that risk assessments have been bogged down for a long time and that is certainly true," Cranor said. "Dioxin is notorious."
Many experts say that the strong influence of industry groups has hampered the EPA's process of judging the dangers of chemicals that may be harming human health and ecosystems.
"There’s every incentive to complicate the risks assessment, to make it as detailed, as data-heavy and as data-obscured as possible, because that just delays doing anything about the product that may be causing harm," Cranor said.
"There are legitimate differences in scientific judgment. And then there’s contamination by people who have no interest in figuring out things correctly and are arguing for a political outcome," he added.
More focused assessments
The committee concluded that "a number of improvements are needed to streamline EPA’s risk-assessment process to ensure that risk assessments make better use of appropriate science and are more relevant to decision-making."
One key change, the scientists said, is that the EPA should alter how it designs its assessments so that they are “more closely tied to the questions” that policymakers want answered.
Under the current strategy, the EPA calculates the probability that a certain chemical is hurting people or wildlife. Instead, the committee said, the agency should address what options are available to reduce hazards or exposures and then figure out what information they can provide to help regulators analyze the merits of those options.
Lauren Zeise, a member of the National Research Council committee, said this upfront planning is critical to stopping risk reports from getting bogged down in details that may not even be helpful to policymakers.
"You’ve got to think about what kind of decision will be made with these risk assessments. You want to match the assessment to the question you are trying to answer," said Zeise, who is chief of reproductive and cancer hazard assessment at the California's Office of Environmental Health Hazard Assessment but was speaking only as a member of the national committee. "Making this an explicit exercise frames the degree of the analysis and the complexity and what questions should be asked."
The scientists proposed bringing regulators, scientists and stakeholders together before the assessment begins to set a deadline and determine what key questions need to be addressed. They warned, however, that they are “mindful of concerns about political interference in the process” and that it is imperative that risk assessments “not be inappropriately influenced” by regulators and others.
“This needs to be a formal process, open and transparent, with clear deadlines," Zeise said.
Another key recommendation is that EPA set a clear standard that requires strong evidence whenever the agency decides to disregard common scientific assumptions. Under the committee's proposal, the EPA could cast aside these so-called "defaults," or assumptions, only when the alternative is "clearly superior." This, for instance, would mean that the EPA would have to consider animal cancer data relevant to humans unless there was new scientific evidence for a chemical that clearly outweighed that long-held assumption.
“We thought the EPA's approach was unclear and we raised some concerns about it. What we’re suggesting is that they develop an evidentiary standard. Assessments can get bogged down quite a bit because of this whole issue of defaults," Zeise said.
In the report, one unidentified scientist on the committee criticized a new EPA policy that allows the agency to ignore sound scientific inferences whenever new data questions them. The scientist called it a "definitive and troubling shift" that can lead to "the paralysis of having to re-examine generic information with every new risk assessment."
The agency also needs a consistent approach to handle scientific uncertainties and to ensure that the differences between individuals, such as infants or pregnant women, are considered, the panel reported. Many U.S. policymakers, in the absence of certainty, decide against regulating some substances. The panel said while uncertainty cannot be eliminated, it can be better communicated to regulators.
Cranor said he is most enthusiastic about the recommendations to focus on how people's individual risks vary. He said it is "very important" for the EPA to gauge the dangers that chemicals, such as perchlorate, pose to children, who have a bigger body burden of contaminants, and people with diseases. “Things like this have to be taken into account. I think this NAS report opens up that possibility," said Cranor, author of the book Toxic Torts: Science, Law, and the Possibility of Justice.
The scientists told the EPA to put more emphasis on non-cancer effects of contaminants, to develop more sophisticated ways to analyze cumulative exposures to multiple chemicals, and to overhaul how it determines what dose of a chemical is considered safe. The agency should examine each chemical's effects on human health, such as how it contributes to a disease, and not assume there is a minimum exposure, or threshold, for causing effects, the committee said.
Don't wait for new technology
Because the changes are substantial, the panel recommended that the EPA phase in the new strategy with a series of demonstration projects.
"Some of these things we are suggesting are transformational. But some things could be done rather soon," Zeise said.
New technologies could vastly improve risk assessments by answering lingering questions about the risks that chemicals pose to human health. But they are at least a decade away so the EPA should not wait, the panel said.
While the committee's recommendations are valid, "the key thing is whether there will be support" for such substantial changes within the government, said UCLA's Jackson, former director of the federal government's National Center for Environmental Health.
Cranor said the biggest limitation of the recommendations is that they would come under existing U.S. laws, which he said do not require chemical companies to supply adequate data about the dangers of chemicals before they are used in commerce.
"This document is a valiant attempt to improve the functioning of these laws," he said. "But we wouldn’t have to worry as much about many of these substances if we had far superior testing and screening of them before people are exposed.”
Download the complete report here from the National Academies Press.
Credits: Photo by Alex Calvin, courtesy flickr.com and used under a creative commons license.