In the last decade, studies by EWG and other researchers have firmly established that toxic chemicals can pass from pregnant women to fetuses through the umbilical cord, affecting children's future health and development. Now a growing body of research shows that some chemicals may alter gene function in ways that can be passed on not only to the immediate offspring, but also to grandchildren and perhaps even great-grandchildren.
The impact of toxic chemicals on generations of offspring with no direct exposure to the contaminant is known as a transgenerational effect. Increasingly, scientists find that short-term exposures during pregnancy to some chemicals can cause reproductive system damages, alter body weight, and even increase the risk of cancer for great-grandchildren of exposed animals.
These impacts are thought to be passed down through modification of the epigenome – the pattern of gene markers that change DNA to fine tune the functioning of specific cells in the body. The study of why and how this happens is called epigenetics.