Is a Common Plastic to Blame for Anxiety?

Plastics are everywhere, and in recent years, the effects of microplastics on human health have become a growing concern. While much of the public conversation on microplastic exposure focuses on physical health, there are increasing questions about the role of microplastics in mental health—especially as we grow to understand more about the link between psychiatric problems and physical processes such as inflammation.

Now, new research suggests a startling connection between early exposure to a common plastic and later development of debilitating anxiety—at least, in rats.

Details of the Study

In a study just presented at ENDO 2026, the annual meeting of the Endocrine Society in Chicago, researchers from the University of Buenos Aires School of Medicine gave pregnant rats oral doses of DEHP—otherwise known as di-(2-ethylhexyl) phthalate, a chemical commonly added to many household plastics to make them more flexible. DEHP is particularly ubiquitous in American life, being present in items often coming into contact with children: from backpacks to vinyl flooring, from rain gear to coatings on chargers for electronics.

In the experiment, the male offspring of the rats who had received DEHP and reached 70 days old were tested in a standard maze protocol. Though all of the rats had had prenatal DEHP exposure, some of the rats also received a GABA agonist, and others testosterone. The DEHP-only rats showed significant anxiety in the maze, as measured by "freezing" behavior, lower curiosity and exploration, and a heightened tendency to stay only in the enclosed parts of the maze.

The rats who had also been exposed to the GABA agonist or testosterone, however, seemed to have relatively less anxiety than the DEHP-only rats. This suggests that GABA and testosterone might play a protective role in mitigating the anxiety-increasing effects of microplastic exposure.

Are There Human Implications? Further Research Is Needed

Do these results apply to humans in the same way? That is unknown. Yet we do know that microplastics have been found to have lasting physiological effects in the body. Despite increased awareness, microplastic exposure also seems to be as high as ever, with anxiety also at record levels in many populations. More research can help clarify this relationship, including the potentially intriguing effects of GABA and testosterone. In the meantime, this seems like one more reason to choose a material other than plastic wherever possible—especially during pregnancy or while raising young children.