In daily life, everyone is exposed to a certain degree of chemical substances from household products, food, packaging and the environment. These substances can even reach unborn children via the mother’s womb or placenta. The level of exposure is usually very low, but some substances can disrupt the hormone system and have negative consequences for health, as PhD Candidate Virissa Lenters discovered over the course of her research.
Lenters examined whether combinations of exposure to specific chemicals, such as pesticides, perfluorinated compounds and flame retardants, can have negative effects on human health. To do so, she used a new generation of statistical models in epidemiological studies.
Lower birth weight, less testosterone
Her research shows that pregnant women with higher concentrations of these chemicals in their blood have babies with a lower than average birth weight. This in turn increases the risk of diseases later in life. In a group of young men, exposure to phthalates, which are present in plastics, correlated to depressed testosterone levels. Exposure to polychlorinated biphenyls (which have been outlawed for years, but are still present in the environment) were related to lower sperm quality. In a third study, Lenters found a relationship between several chemical substances and the diversity of the intestinal flora. She found no evidence, however, for the hypothesis that this would increase the risk of asthma.
Better protection against harmful substances
“My research shows that some new statistical models are better able than traditional methods to determine the influence of compounds of chemical substances on health”, says Lenters. “These new methods will eventually lead to better protection of public health against harmful chemical substances.”