Scientists Discover 42 New ‘Mystery Chemicals’ In Humans Never Found In People Before

Scientists Discover 42 New Mystery Chemicals Never Found In Humans


Scientists have discovered 55 chemicals that have never been reported in humans before now, including 42 they classified as “mystery chemicals.”

If the possibility of having “mystery chemicals” inside your body doesn’t sound good, it’s because it’s not.

The study, conducted by scientists at University of California-San Francisco (UCSF), was published in the March 16, 2021 edition of Environmental Science & Technology.

According to, the chemicals, found both in the blood of both pregnant women and their newborn children, are believed to have come from consumer products or other industrial sources.

“These chemicals have probably been in people for quite some time, but our technology is now helping us to identify more of them,” said Tracey J. Woodruff, Ph.D., a professor of obstetrics, gynecology and reproductive sciences at UCSF.

“It is alarming that we keep seeing certain chemicals travel from pregnant women to their children, which means these chemicals can be with us for generations.”

Alarming would certainly be one way to describe these findings.

While these chemicals can be tentatively identified using chemical libraries, they need to be confirmed by comparing them to the pure chemicals produced by manufacturers that are known as “analytical standards.” And manufacturers do not always make these available.

Recently, for example, chemical manufacturer Solvay stopped providing access to a chemical standard for one perfluorooctanoic acid (PFAS) compound that has emerged as a replacement for phased-out PFAS compounds. The researchers have been using this chemical standard to evaluate the presence and the toxicity of the replacement PFAS.

Co-lead author Dimitri Panagopoulos Abrahamsson, Ph.D., a postdoctoral fellow with UCSF’s PRHE, said, “Our study findings also make clear that chemical manufacturers need to provide analytical standards so that we can confirm the presence of chemicals and evaluate their toxicity.”

All in all, they found 109 different chemicals in the blood samples of pregnant women and their newborns.

The scientists determined that 40 of them are used as plasticizers, 28 are used in cosmetics, 25 in consumer products, 29 as pharmaceuticals, 23 as pesticides, three as flame retardants, and seven are PFAS compounds, which are used in applications such as carpeting and upholstery.

According to the researchers, a mind-boggling 55 of thosee 109 chemicals found appear to have never before been reported in people.

One is used as a pesticide, two are are PFASs, 10 are used as plasticizers, two are used in cosmetics, four are high production volume (HPV) chemicals, and a whopping 37 of them, according to, “have little to no information about their sources or uses.”

“It’s very concerning that we are unable to identify the uses or sources of so many of these chemicals,” said Dr. Woodruff. “EPA must do a better job of requiring the chemical industry to standardize its reporting of chemical compounds and uses. And they need to use their authority to ensure that we have adequate information to evaluate potential health harms and remove chemicals from the market that pose a risk.”