Young girls may be experiencing puberty earlier as a result of exposure to chemicals found in shampoo, perfumes and deodorants, a new study has suggested.
According to a paper on the scientists’ findings, published in the journal Human Reproduction, female offspring of women with higher levels during pregnancy had sexually matured at an earlier age, although no difference was found in male offspring.
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Lead researcher Dr Kim Harley, associate professor in public health at the University of California, Berkeley, said: “Mothers who had higher levels of two chemicals in their bodies during pregnancy - diethyl phthalate, which is used in fragrance, and triclosan, which is an antibacterial agent in certain soaps and toothpaste - had daughters who entered puberty earlier.
“We also found that girls with higher levels of parabens in their bodies at the age of nine entered puberty earlier. One hypothesis is that chemicals in the environment might be playing a role, and our findings support this idea.”
Recent studies have shown that puberty is typically starting at around the age of ten among girls in developed countries - at least five years earlier than a century ago. Harley’s team warn that earlier puberty for girls can increase the risk of mental health problems as teenagers, as well as breast and ovarian cancer later in life.
However, as The Times notes, the new study does not prove that the link between the chemicals and early puberty was causal. “It may be partly explained, for instance, by girls using shampoo and deodorant more when they hit puberty early,” the newspaper says.