Researchers at Uppsala and Karlstad universities in Sweden discovered that the chemical bisphenol F (BPF) found in plastic can cause changes in genes that are important for the development of nervous system.
According to scientists, external factors can cause changes in the gene expression through an epigenetic mechanism. This means that individual genes are modified by the "methylation" method. Increased methylation in DNA makes it harder for the cellular machinery to read that particular part. As a result, the expression of methylated genes is often impaired.
In this study, the scientists measured BPF level in the urine of pregnant women during the first trimester, then kept record of their babies after birth. DNA methylation and cognitive abilities were examined in children at age ̃7. Because the fetus contacts mother's blood through placenta, it is also exposed to substances in its mother's body.
Women are exposed to many plastic chemicals that affect the neural development in their children.
The results of the analysis demonstrated that in fetuses exposed to higher levels of BPF, methylation increased in a specific part of the GRIN2B gene, which has an important role in the nervous system. Furthermore, higher methylation is associated with lower IQ in children.
However, the study also showed that the susceptibility of these children to BPF varied by sex. Specifically, the epigenetic link between BPF and mental capability was observed only in boys.
In their previous study, researchers discovered that 25% of examined 7-year-olds who were exposed to the highest extent of bisphenol F, during the 10th week of pregnancy, experienced a 2-point decrease in total IQ compared with 25% of children who were exposed to the lowest extent. This is a tiny difference that is not easily seen in a child but, on the other hand, it eventually becomes noticeable on a population scale.
This discovery can be used to explain why exposure to this chemical during fetal development may be associated with lower IQ scores at 7 year-old kids.
Source: Healthy life