Microplastics are now present almost everywhere: in the oceans, in drinking water, on food packaging and even in the human body. But the question of what consequences continuous exposure to them may have on health remains an issue under study.

A new study from the College of Veterinary Medicine and Biomedical Sciences at Texas A&M has analyzed the impact of polyethylene, one of the most widely used types of plastic in the world. The findings, published in the journal Science Advances, suggest that exposure to it may be linked to changes similar to those seen in fatty liver disease, with the effects appearing to be amplified when exposure is combined with a diet high in fat, fructose and cholesterol.

Polyethylene, a plastic present in everyday life

Polyethylene is widely used in food packaging, plastic wrap, storage containers and other everyday materials. According to researchers, it accounts for about a third of global plastic production, but its impact on the liver has been less studied than some other types of plastic.

The research team focused on the question of whether exposure to polyethylene could contribute to the development of changes associated with fatty liver disease, a condition in which fat accumulates in liver cells.

The results showed increases in several markers associated with the disease. The effect was even more pronounced when polyethylene exposure was combined with a Western-style diet, high in fat, fructose, and cholesterol.

According to the researchers, this raises the possibility that exposure to microplastics and a diet that burdens metabolism may act together to increase stress on the liver.

How was the damage identified?

To better understand the mechanisms involved, the scientists used spatial transcriptomics, a technology that enables the analysis of gene activity within tissues, while preserving the location of cells.

Through this method, the researchers identified specific areas of liver damage and observed the activation of PPAR-alpha, a protein that plays an important role in regulating fat metabolism in the liver.

They also identified ANXA2, a gene associated with tissue repair processes, as a potential factor in the observed mechanism.

According to the team, identifying these biological pathways could help to better understand how microplastics may affect the organism and, in the future, to develop potential therapeutic strategies.

Can polyethylene lead to more serious injuries?

The study does not provide a definitive answer on the long-term impact of microplastics on humans. The researchers plan to analyze whether polyethylene may also play a role in more advanced stages of liver disease, including fibrosis, and whether interfering with the PPAR-alpha pathway could help limit the harmful effects.

However, the results do not mean that a single plastic product or a single exposure causes liver disease. The study provides primarily experimental data that warrants further investigation, particularly to understand whether these effects replicate in humans.

At a time when microplastics have become part of daily exposure, researchers emphasize the need to better understand the interaction between them, nutrition, and other factors that affect liver health.