There are several risk factors for obesity including metabolic diseases, genes and lifestyle. Now, a team of researchers has found that exposure to DDT during the 1950s could have raised the risk of obesity in the present generation.
The study, conducted by Washington State University researchers, found that the chemical didn't cause any visible changes in the offspring of rats that were exposed to DDT. However, more than half of third generation rats- males and females- developed obesity.
"What your great-grandmother was exposed to during pregnancy, like DDT, may promote a dramatic increase in your susceptibility to obesity, and you will pass this on to your grandchildren in the absence of any continued exposures," said Michael Skinner, WSU professor and founder of its Center for Reproductive Biology.
Skinner's lab has earlier documented effects of many toxicants including pesticides, fungicides, dioxins, hydrocarbons and bisphenol-A or BPA. However, DDT had the greatest effects on obesity than any other chemical studied by his team.
According to the researchers, the study is an example of transgenerational epigenetic inheritance, where environmental factors change the way genes are expressed across generations. In recent years, there has been a lot of interest in learning how toxicants affect the gene function in future generations.
The U.S. banned the chemical Dichlorodiphenyltrichloroethane (DDT) way back in 1972, which was used as a pesticide in the country and was also used to kill lice. The chemical can pass from a mother to the fetus and can contaminate breast milk of the mothers exposed to DDT.
A recent study published in the journal Environmental Health Perspectives had found that DDT exposure in womb can lead to high blood pressure in women.
DDT is still used in many countries to fight mosquitoes. However, a panel of experts had earlier recommended that the chemical shouldn't be used as it has been known to cause serious health concerns.
The present study is published in the journal BMC Medicine.