How Tobacco Companies Use Chemistry to Get around Menthol Bans

3 June 2024

By Julie B. Zimmerman, Hanco C. Erythropel, Tobias D. Muellers, Predrag V. Petrovic, Stephanie S. O’Malley, Suchitra Krishnan-sarin, Sairam V. Jabba, Sven E. Jordt & Paul T. Anastas, Scientific America

Regulating chemicals one-by-one has allowed the tobacco industry to skirt menthol bans by creating new additives with similar effects but unclear safety profiles

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.

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.