Emerging Pollutants 1: Substances on First Step Toward Regulation

Chemicals dominate modern life. They’re in the air we breathe, the food we eat, the products we use daily, and the rivers and soils that sustain us. Many are harmless, even helpful, but some carry risks. For regulators, it’s a daunting task to figure out which of the millions of compounds that swirl around us are potentially harmful. In this series of articles, 3E will help you navigate emergent pollutants to examine which substances are likely to attract regulatory attention in the future.

When regulators decide to act on a chemical, they rarely make the decision overnight. Years of research, public pressure, and mounting evidence have usually paved the way. But before any formal restrictions come into play, many substances begin their regulatory journey under a more informal label: “emergent pollutants” — or, in scientific parlance — “contaminants of emerging concern” (CECs).

These are substances that scientists are starting to flag, often because they have already been found in the environment and/or because their chemistry suggests that they could be harmful. CECs are not yet controlled by regulation, but they are moving into the spotlight, making it prudent for the chemical industry to take note.

What Makes a Pollutant “Emerging”?

Leon Barron, an analytical chemist who leads the Emerging Chemical Contaminants Team at Imperial College London, spends his time studying how pollutants move through and interact with the environment. He stresses that the CEC label is not meant to alarm consumers or the public but does signal the need for greater scrutiny from scientists and governments.

“A contaminant of emerging concern is a substance that has been detected, or is very, very likely to be detectable in the environment, and given its nature, is likely to pose some level of risk to wildlife or humans,” Barron told 3E. “That doesn’t mean we should be running around being scared of them. Context and concentration matter enormously.”

Nuance is essential here. Some substances sound dangerous on paper but occur in such low concentrations that they pose little risk. Others may be widely used and benign in some contexts but damaging in others. It’s the job of scientists like Barron to produce data and evidence to provide clarity on CECs, helping regulators figure out the risks they pose.