Plastic, which is now common, contains endocrine-disrupting chemicals, or EDCs (内分泌干扰物), that has been linked to increased risk of many chronic diseases. Parental exposure to EDCs, for example, has been shown to cause metabolic (新陈代谢的) disorders, including obesity and diabetes, in the later generations.
Led by Changcheng Zhou, a professor of biomedical sciences in the School of Medicine at the University of California, the researchers investigated the impact of fathers' exposure to a phthalate called dicyclohexyl phthalate, or DCHP (邻苯二甲酸二环己酯), on the metabolic health of first generation (F1) and second generation (F2) in mice. Phthalates are chemicals used to make plastic more durable.
The researchers found that fathers' DCHP exposure for four weeks led to high insulin (胰岛素) resistance and impaired insulin signaling in F1. The same effect, but weaker, was seen in F2.
"We found fathers' exposure to EDCs may have intergenerational and transgenerational detrimental effects on the metabolic health of their later generations," Zhou said. "To the best of our knowledge, our study is the first to demonstrate this."
In the case of fathers' exposure in the study, intergenerational effects are changes that occur due to direct exposure to a stressor, such as exposure to DCHP of fathers (FO generation) and his Fl generation. Transgenerational effects are changes passed down to later generations that are not directly exposed to the stressor (for example, F2 generation).
"This suggests that fathers' DCHP exposure can lead to sex-specific transgenerational effects on the metabolic health of their later generations," Zhou said.
Zhou stressed that the impact of exposure to DCHP on human health is not well understood, even though DCHP is widely used in a variety of plastic products and has been detected in food, water, and indoor particulate matter.
"It's best to minimize our use of plastic products," Zhou said. "This can also help reduce plastic pollution, one of our most pressing environmental issues."