In 2020, lawmakers in California and Massachusetts banned menthol, a chemical that causes a cooling sensation, as an additive in cigarettes. The idea was, in part, to curb youth smoking; menthol makes cigarettes more palatable by creating a “cooling” sensation. Regulators had deemed the chemical unsafe for its role in promoting nicotine addiction.
Soon after, we learned in detail how the tobacco industry circumvented these laws by substituting menthol with other cooling chemicals in their new “nonmenthol” cigarettes and other tobacco products. This is the oldest trick in the book when dealing with chemicals deemed hazardous or otherwise problematic: stop using the original molecule and either find or make a substitute with the same function but for which safety data are scant or nonexistent. This allows the company to continue to produce chemicals of concern while the agencies like the Food and Drug Administration or the Environmental Protection Agency grind away to catch up to these new alternatives.
So while these new products may be legal, the original concerns remain. In this case, R.J. Reynolds simply substituted menthol with an odorless, synthetic cooling agent known as WS-3, that has the same chilling effect that the menthol bans were intended to address. In fact, WS-3 has a very similar base molecular structure to menthol, with some tweaks. Regardless, the cooling sensations elicited by both menthol and WS-3 reduce the harshness of cigarette smoke, thus maintaining cigarettes’ appeal.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
That the tobacco industry can readily do this speaks to a fatal flaw in how we regulate chemicals in this country—not by what the concern or intended effect of a compound is, or what we know about related compounds, but chemical by chemical, final product by final product. However, no one wants to merely eliminate an individual chemical; we want to eliminate the underlying concerns that triggered regulations in the first place. That is, in the case of these cigarettes, stopping the “cooling” effect that makes smoking more pleasant regardless of the actual molecule that is providing the sensation. The status quo means that regulators are constantly chasing tiny tweaks and clever substitutions instead of regulating classes or, better, the properties that make the molecules concerning.
This whack-a-mole plays out in all kinds of products—not just cigarettes: We ban an individual chemical that gets replaced with another that is not on a restricted substances list. We saw this same story play out for bisphenol A, a plastics precursor and endocrine disruptor that interferes with the normal production and work of the body's hormones. As bisphenol A (BPA) became increasingly regulated by countries around the world, it was replaced with bisphenol S (BPS), which contains only a slight modification to the molecular structure of BPA. Although BPS helped achieve the goal of removing BPA from commercial products, products containing BPS also cause the same endocrine problems. By banning BPA, we removed the chemical, yet not the concern.
So why has this obvious flaw been allowed to continue? First, it isn’t recognized as a flaw. Perhaps this is best explained as, “Chemicals have rights too” in the U.S. There is a prevailing perspective that when we move to regulate a chemical, we are putting that compound “on trial” where the evidence generally needs to meet a certain standard of peer review and the process needs to include public review and comment. Sadly, the U.S. chemical regulatory system moves more slowly than even our judicial system. For instance, it has taken many years for regulatory action to be taken on known problematic substances—such as dichloromethane, chloroform and trichloroethylene—where the science confirming the hazard is well established. But the pace of the legally required review of the science and the regulatory costs is sadly not the biggest impediment.
The biggest problem is that we focus on the chemical and not the concerns (e.g., toxicity, addictive nature, etc.). What does that mean? It means that the ability of a chemical to cause harm is based on the combination of its inherent physical and chemical properties. Its ability to make someone sick or change our atmosphere is not based on how we humans name it—and yet, that is how we regulate—one discrete chemical at a time.
Slow. Laborious. Costly. Ineffective.
It doesn’t have to be that way.
Changing this regulatory framework can be beneficial to the chemical industry by incentivizing sustainable innovation while also being more effective in protecting public health and the environment. Using our understanding of how physical and chemical properties relate to different concerns gives us a new way to protect human health—by regulating the concern and not chemicals. We can define groups of chemicals, based on similar physical and chemical properties, that are safe, and those that are concerning. This approach is based on intrinsic molecular properties causing both hazard and function rather than individual chemical structure. Regulators can use this insight when a new chemical is proposed for commercial use. Innovative companies can benefit by inventing new substances based on this knowledge to design molecules that are more likely to be safe. This approach also creates greater regulatory certainty, reducing a company’s risk in bringing a chemical to market or putting a chemical in their product that might eventually be banned.
For cigarette coolants, this would mean banning any chemical, regardless of structure, that activates the receptor for menthol, named TRPM8. This receptor is located on sensory neurons that enable us to feel cool temperature and is also activated by coolants such as WS-3 found in the new “nonmenthol” cigarettes. Menthol cigarettes have already been banned in Canada, the European Union and other countries, with some countries such as Germany and Belgium, banning diverse TRPM8 activators. Interestingly, the Belgian approach specifically restricts any additives to tobacco products that “facilitate nicotine inhalation or intake,” including “all components and mixtures with cooling and/or analgesic effects.” This is essentially a property-based approach.
A property-based approach can be used to help define safer chemical space—and provide regulatory confidence—as well as outline hazardous chemical space, in which chemicals with certain properties known to be associated with hazard would come under greater scrutiny. Fortunately, leading companies across the many industrial sectors—from cosmetics to electronics—are beginning to think and design in this way.
If we seek to have a chemical world that is truly safe and sustainable by design, we should match our regulatory framework to our intentions. That is, rather than ban individual molecules leading us to chase each new molecule of concern for decades with a new regulation, we should aim to ban the intrinsic concern defined by a set of defined physical-chemical properties. This would lead to chemicals that are safe for people and the planet, based on their intrinsic, safe properties.
Fast. Agile. Efficient. Effective.
In this way, the aim of protecting vulnerable people from additives that make cigarettes more appealing and pleasant would have been realized rather than seeing those hopes go up in smoke.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.