Common ‘forever’ chemicals found in drinking water, among other things, have been linked to early menopause in women, raising new concerns over the contaminants. The study builds upon an existing body of research that has linked per- and poly-fluoroalkyl (PFAS) chemicals with a number of health issues, including everything from thyroid disease to certain types of cancers.

The latest study was recently published by the Endocrine Society, which found that women who had higher levels of PFAS chemicals in their blood also experienced menopause an average of two years earlier than women who had lower levels.

This has implications for one’s overall health; early menopause can lead to heart and bone health issues, as well as an overall decrease in quality of life.

PFAS are called ‘forever’ chemicals because they do not break down in the body, where they will accumulate over time. Many people are exposed to these chemicals from drinking water — the Endocrine Society says that around 110 million Americans may be exposed to these chemicals in their tap water. The contaminants may come from a variety of sources, including the foams used to fight fires and things like nonstick cooking pans.

In May 2016, the EPA published a document [PDF] detailing sources of exposure to these synthetic chemicals, stating that ‘major’ ones include drinking water, food, as well as many consumer products like water repellants, flame repellants, certain food containers, contact paper, and more.

Avoiding these chemicals is tricky, unfortunately. Earlier this year, a study found that while some water filters can remove these substances, the most common types like activated carbon filters were less effective and certain options — namely whole-home water filtering systems — were found to potentially increase exposure to these chemicals.

The most recent study’s lead author Ning Ding, Ph.D., MPH, explained:

PFAS are everywhere. Once they enter the body, they don’t break down and build up over time. Because of their persistence in humans and potentially detrimental effects on ovarian function, it is important to raise awareness of this issue and reduce exposure to these chemicals.