by Christopher Gerry
Weathering over fifty years’ worth of damning scientific evidence, asbestos, a known carcinogen, appears as resistant to American legislation as it is to fire, electricity, and heat. Asbestos is a naturally occurring fibrous substance with properties that make it an attractive material for use in construction and manufacturing. An overwhelming amount of evidence, however, has linked ingestion or inhalation of microscopic asbestos fibers to cancer—most notably a rare disease called mesothelioma—and no level of asbestos exposure is safe.
Despite these risks, roughly 125 million people worldwide are exposed to asbestos while at work: shipbuilders, miners, electricians, and other blue-collar workers are at particularly high risk. In response, over 50 countries have banned all future uses of asbestos. While these bans must be coupled with the removal of existing asbestos products to be effective, they are a logical and productive first step. The United States, unfortunately, is still crawling.
Scientific evidence and human behavior diverge more frequently than this scientist would like to admit. Public opinion differs significantly from the scientific consensus on many important topics, but public opinion doesn’t seem to be the force that’s standing in the way of meaningful asbestos regulation. Instead, special interests appear to be subverting both scientific evidence and the will of the public. Politicians will need to craft robust legislation that’s capable of withstanding attacks from those who have a vested interest in asbestos’ success.
The ongoing battle in your body
The dangers of asbestos exposure have been known for over half a century. Research from the 1960s led by Dr. Irving Selikoff, who had previously co-developed a revolutionary tuberculosis drug, helped to establish the causal link between asbestos and diseases like mesothelioma and lung cancer. After noticing that a handful of workers from a local asbestos plant were dying of rare lung-related illnesses, Dr. Selikoff conducted several large studies that detailed the consequences of asbestos exposure. He observed that asbestos workers had significantly increased rates of cancer and mortality, and that some patients who had worked with asbestos for less than a week had detectable lung scarring 30 years later.
One of Dr. Selikoff’s most striking observations was the “remarkably high” incidence of mesothelioma. Mesothelioma is a rare (~3,000 cases per year in the United States) but highly lethal cancer of the tissue that lines your internal organs, most commonly the lungs. While most people who are exposed to asbestos will never develop the disease—only 3% of the workers in Dr. Selikoff’s study died of mesothelioma—asbestos accounts for over 80% of mesothelioma cases.
It’s unclear how asbestos exposure leads to mesothelioma, but one hypothesis involves our own immune systems. When inhaled asbestos fibers accumulate in the lungs and cause damage to the surrounding tissue, the body responds via a process called inflammation. This process recruits immune cells to the site of an injury to try to remove the problem and fix the damage that it caused. Inflammation promotes cell healing and growth, but it also generates chemicals that can damage the genetic material of nearby cells. When these “mutated” cells are encouraged to grow, they sometimes do so in an uncontrolled manner that leads to cancer. Short-term inflammation doesn’t cause cancer, but people exposed to asbestos suffer from chronic inflammation that can last for decades because the body is terrible at clearing asbestos fibers from the lungs.
The past battle in the legislature
Laws passed in the 1970s allowed federal authorities to regulate the use, distribution, and manufacture of asbestos. One of the most consequential pieces of legislation in this arena was the Toxic Substances Control Act (TSCA) of 1976, which afforded the Environmental Protection Agency (EPA) authority over new commercial chemicals and existing chemicals that posed an “unreasonable risk of injury to health or to the environment.”
Several years of increasingly stiff regulations culminated in the EPA’s attempt to leverage the TSCA to enact an outright ban on almost all asbestos-containing products in 1989. Asbestos mining companies and product manufacturers quickly filed a lawsuit (supported by the Canadian government) challenging the ban, citing the high costs of finding a suitable asbestos alternative.
In the 1991 ruling ‘Corrosion Proof Fittings v. Environmental Protection Agency,’ the Fifth Circuit Court of Appeals unanimously rejected most of the EPA’s ban on technical grounds. It held that the EPA had violated the TSCA by not adequately demonstrating that the asbestos ban was the “least burdensome” action that could achieve an acceptable level of risk. In other words, the TSCA required the EPA to minimize the disruption to those being regulated rather than maximize public health benefits. The ruling also stated that the EPA had failed to prove that its proposed asbestos substitutes were safe, despite the overwhelming (and undisputed) dangers of asbestos itself. Asbestos has not been banned in the United States since.
After the defeat of the ban, incremental asbestos legislation continued to churn through Congress. One such bill passed in 2016 was the Frank R. Lautenberg Chemical Safety for the 21st Century Act, which was the first major amendment to the TSCA. Among other provisions, the Lautenberg Act mandated the EPA to conduct risk assessments of hazardous chemicals and expanded the agency’s power to respond to the results of those studies. The EPA has since declared asbestos to be one of the first 10 chemicals it will evaluate, and it has recently proposed a significant new use rule (SNUR) that aims to curb future manufacturing, importing, and processing of asbestos and asbestos-containing materials.
The upcoming battle in the EPA
The scientific evidence has been strong enough to convince many countries to ban all types of asbestos, so why are American federal agencies still at the “risk assessment” stage? Research is clearly not the problem—the EPA spent 10 years and millions of dollars adding to the already weighty corpus of asbestos research prior to its 1989 ban. Instead, lawmakers have been unable or unwilling to draft legislation strong enough to withstand challenges from lobbyists for the asbestos industry.
The Lautenberg Act was a necessary improvement to the TSCA—the original law couldn’t ban a known carcinogen, after all—but its increased reliance upon the EPA may have made it vulnerable to internal sabotage. President Trump has expressed skepticism about the dangers of asbestos repeatedly and without evidence. His administration’s first EPA Director, Scott Pruitt, was less than eager to discuss asbestos regulation during his confirmation process. And recently, the EPA has decided to ignore the effects of chemicals in the ground, air, or water in their risk evaluations—only direct exposure will be considered.
Despite the common slogan, data rarely speak for themselves. Only time will tell if this new legislation is as strong as the research it’s designed to empower.
Christopher Gerry is a fifth-year graduate student in the Department of Chemistry & Chemical Biology at Harvard University. He currently serves as Co-Editor-in-Chief of the Science in the News blog.