I subscribe to numerous science and health-oriented newsletters that flood my email inbox every day along with a bevy of unsolicited press releases and blog posts. Broadly speaking, the information provided either warns about some risk in our lives or suggests ways to improve our prospects for longevity. Let me address a typical scare that recently popped up.

I don’t use nail polish, but I have followed its historical development given the interesting chemistry involved. So, when I was informed by a barrage of posts that the European Union had banned trimethylbenzoyl diphenylphosphine oxide (TPO), a chemical used in gel nail polish, I was keen to look into the story behind the story.

First, let’s clarify that regular nail polish and gel nail polish employ totally different chemistries and the warning about TPO applies only to the gel variety. Regular nail polish was adapted from paint used by the automobile industry that in turn owes its origin to an accidental discovery. In 1846, Swiss chemist Christian Friedrich Schönbein, as the story goes, spilled a mixture of nitric and sulphuric acids that he wiped up with his wife’s apron. When he tried to dry the apron in front of the fireplace, he was astonished to see it burst into flames and vanish without leaving a residue. The acids had converted cellulose, the main component of cotton, into flammable nitrocellulose. This came to be known as “guncotton” and eventually became the source of smokeless gunpowder that is still the major propellant used in firearms today.

Just months after Schönbein’s discovery, Louis-Nicolas Ménard and Florès Domonte found that nitrocellulose can be made to dissolve in a mixture of ether and ethanol, leaving behind a plastic film upon the........

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