A study conducted by biomedical scientists at the University of California, Riverside, has found that a father’s exposure to microplastics can lead to metabolic disorders in his offspring. The research, which used mouse models and was published in the Journal of the Endocrine Society, is the first to demonstrate a link between paternal microplastic exposure and long-term health effects in subsequent generations.
Microplastics are plastic particles less than 5 millimeters in size that result from the breakdown of consumer products and industrial waste. Previous studies have detected microplastics in human reproductive systems, but this new research is the first to show a direct connection between paternal exposure and health risks for offspring.
The researchers induced metabolic disorders in the mice’s offspring by feeding them a high-fat diet. This approach aimed to highlight any effects of paternal exposure that might not be visible under normal dietary conditions. While all fathers were fed a regular diet, their offspring received a high-fat diet similar to unhealthy eating patterns common in some populations.
The findings revealed that female offspring of male mice exposed to microplastics were more likely to develop metabolic disorders compared to those whose fathers had no such exposure. According to Changcheng Zhou, professor of biomedical sciences at UCR School of Medicine and lead author of the study, “The exact reasons for this sex-specific effect are still unclear. In our study, female offspring developed diabetic phenotypes. We observed upregulation of pro-inflammatory and pro-diabetic genes in their livers — genes previously linked to diabetes. These changes were not seen in male offspring.”
Male offspring did not develop diabetes but showed a small decrease in fat mass. Female offspring experienced decreased muscle mass along with increased diabetes risk.
To investigate how these traits were passed on, researchers used PANDORA-seq technology developed at UCR. They discovered that microplastic exposure altered small RNA molecules within sperm—specifically tRNA-derived small RNAs (tsRNAs) and rRNA-derived small RNAs (rsRNAs). These non-coding RNAs may influence gene expression during development.
“To our knowledge, ours is the first study to show that paternal exposure to microplastics can affect sperm small non-coding RNA profiles and induce metabolic disorders in offspring,” Zhou said.
Zhou also noted broader implications: “Our discovery opens a new frontier in environmental health, shifting the focus toward how both parents’ environments contribute to the health of their children.” He added that men planning families should consider reducing their exposure to substances like microplastics.
The team plans further studies on whether maternal exposure has similar effects and ways these changes might be mitigated. The research involved collaboration with scientists from University of Utah School of Medicine and University of Nevada, Reno School of Medicine and received partial funding from the National Institutes of Health.
“Our future studies will likely look at whether maternal exposure produces similar risks and how these metabolic changes might be mitigated,” Zhou said.
The paper is titled “Paternal microplastic exposure alters sperm small non-coding RNAs and affects offspring metabolic health in mice.”
