A novel study that continued for five decades has unveiled that the ones exposed to high levels of pesticide DDT in womb have four times more likely to be diagnosed with breast cancer.

It has been now many years that the pesticide has been banned in many countries, but in Africa and Asia it still continues to be widely used. Study's co-author Barbara Cohn of the Public Health Institute in Berkeley, California, said, "Environmental chemicals have long been suspected causes of breast cancer, but until now, there have been few human studies to support this idea".

The study is the first to unveil that chemical exposure for pregnant women could have lifelong consequences for their daughter's breast cancer risk. In the research, scientists have assessed a group of women exposed to DDT in utero in the 1960s. It was the time when the pesticide was quite popular in America.

For the reference part, the data came from a California program called Child Health and Development Studies (CHDS). In the data, 20,754 pregnancies were studied from 1959 to 1967. Out of them, the researchers focused on 118 mothers who had daughters and were diagnosed with breast cancer by age 52.

With the help of stored blood samples, researchers came to know how much DDT exposure they had when they were pregnant and shortly after birth. The chemicals in DDT are known to be endocrine disruptors that can imitate and interfere with the function of the hormone estrogen.