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EPA Begins Evaluating 10 Common Chemicals for Toxicity

Known and suspected carcinogens including asbestos are among the first compounds to be scrutinized under a reformed law

Workers removing asbestos, a known human carcinogen.

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The EPA has started flexing its newfound powers to control chemicals in the U.S. Last week the agency announced the first 10 compounds it will evaluate for safety under the reformed Toxic Substances Control Act (TSCA). The legislation, amended last June, strengthens the agency’s authority to regulate new and existing chemicals. Its list, which includes substances such as asbestos, is just the beginning of its revamped efforts.

In the coming years, the U.S. Environmental Protection Agency plans to review thousands of chemicals for their potential risk to human health and ecosystems. It could restrict or ban any of them—something the EPA has had little power to do before. “These 10 chemicals are not new, they’ve been in use for decades,” explains Richard Denison, alead senior scientist at the Environmental Defense Fund. “But under the old law, there was no mandate for EPA to review those chemicals—that’s part of why this reform was so important.”

TSCA is the U.S.’s main chemical regulatory law. It covers substances that industries and businesses use and well as chemicals found in consumer products. Congress passed the TSCA in 1976, giving the EPA authority to assess new chemicals and restrict or ban them if they “present an unreasonable risk of injury to health or the environment.”


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The weakness, however, was that chemicals existing before the 1976 law—about 62,000 of them—were grandfathered in. “They were presumed to be safe,” Denison says. “Only if EPA could muster the information to make a very strong case for regulating those chemicals, could they be touched.” The EPA did not have much power in reviewing new chemicals either. If the agency needed critical information, it could only ask companies for data they already had—the EPA could not require additional testing unless it had strong evidence the compound presented a potential risk. That allowance created a catch-22, because risk was hard for the EPA to prove without the necessary data. “The burden was on the EPA,” Denison notes. “And the agency was forced to let chemicals on the market in the absence of information.”

Other parts of the law also made it hard for the EPA to exercise real oversight—for instance, the EPA had to consider the cost of regulating when evaluating a substance, rather than just considering health. In over 40 years under the original TSCA law the agency reviewed only a tiny portion of thousands of chemicals used in the U.S., and it restricted only five existing and four new ones.

The reformed law changes this dynamic. It requires the EPA to review all new and existingchemicals on the market. For new ones, the EPA must then make a finding on whether or not it is a risk to humans or the environment before it enters the market. If the EPA does not have enough information to definitively decide, it will hold up that chemical until it gets the data it needs. The agency has more power to require testing now as well. And under the reformed law, the EPA has a completely health-based safety standard for its evaluations, rather than one that takes into account costs of regulation.

Over the next three years, the agency will collect information on the uses of the first 10 chemicals, people’s exposure, hazard, persistence in the environment and other factors. “EPA needs to have a very comprehensive picture of these chemicals,” Denison says. It will then decide whether any among the 10 pose an “unreasonable risk” to the environment or human health. For those that do, the EPA has two years to create regulations that mitigate the risk. The list includes the following chemicals:

  • 1,4-dioxane

  • 1-bromopropane

  • asbestos

  • carbon tetrachloride

  • cyclic aliphatic bromide cluster

  • methylene chloride

  • N-methylpyrrolidone

  • pigment violet 29

  • trichloroethylene

  • tetrachloroethylene (also known as perchloroethylene)

 

The EPA list is not a huge surprise to experts in the industry—it falls in line with the intentions of the reform. Each substance ranks high for hazard and exposure, and some are persistent in the environment. “The EPA has taken a lot of care to select these chemicals that many people would agree are a no-brainer for action,” says Lynn Goldman, dean of The George Washington University’s Milken Institute School of Public Health.

Asbestos, probably the most infamous chemical on the list, is a known human carcinogen and is stillused in the U.S. in some building construction materials and auto parts. (Despite common belief, most uses of asbestos are not already banned—although its use has declined.) A few compounds on the list, such as trichloroethylene, are designated as probable human carcinogens. (Trichloroethylene is used as a refrigerant, solvent and a dry cleaning fluid, and is present in drinking water, indoor environments, soil and other sources.) The other chemicals on the list are categorized either as possible human carcinogens, having reproductive toxicity or acute aquatic toxicity. A full description of exposure sources and hazards appears on the EPA list.

Goldman has worked in the field for decades—she was assistant administrator for toxic substances at the EPA during the Clinton administration and worked in environmental health for the California Department of Public Health—and she says that she’s been aware of many of the chemicals on the EPA list for years. “Over the years a lot of evidence accumulated in terms of them being probable or known carcinogens,” she says.

Of course, there are other chemicals noton this initial list that the public or advocacy groups would have liked to see included, but that’s not too surprising either. “If Congress had asked the EPA to review 20 or even 50 in the first group, they could have easily done that,” Goldman notes. Denison agrees: “Trying to select 10 is a challenge,” he says, “There are many more that warrant such scrutiny.”

Experts are hopeful that President-elect Donald Trump’s administration will not try to block or slow down the implementation of the reformed TSCA law—given his anti-EPA and antienvironmental rhetoric—because Congress passed the bill with near-unanimous bipartisan support as well as industry backing. There is “some room for optimism,” Denison says. Just a day after the EPA released its list, a bipartisan group of nine senators wrote a letter to Trump’s transition team, imploring the incoming administration to “vigorously implement the new law.”