Prenatal exposure to chemicals found in plastics and pesticides may leave some people more prone to obesity later in life, a scientist said yesterday.

Research by Fred vom Saal, of the University of Missouri-Columbia, suggested that mice were more likely to put on weight if their mothers were fed compounds that disrupt the normal activity of hormones.

The young mice tended to be born very small but doubled their bodyweight in seven days. They were then more likely to remain obese in adulthood.

While the findings applied only to mice, and there was no evidence for a similar effect in humans, Dr vom Saal said that they were of concern because one compound he studied, bisphenol-A, was often found in babies’ bottles. Such chemicals could be contributing to the rise in obesity, he said.

Independent obesity experts, however, said that the rise in adult obesity had occurred over a period in which average birth weight had gone up, not down. Dr vom Saal suggested that the likely reason explanation for any link was that exposure to chemicals in the womb could encourage a “thrifty” metabolism, in which energy was stored as fat.

“This individual could eat the same and exercise the same as someone with a normal metabolic system, but he or she would become obese while the other person remained thin,” he said Professor Richard Sharpe, of the University of Edinburgh, said that metabolic syndrome disorders were likely to be caused by the combination of several factors, including genetic make-up, lifestyle and diet.

He added: “New research must prove to be repeatable if we are to take it seriously.”

85,000

Approximate number of chemicals being screened by the US Environmental Protection Agency for hormone-disrupting effects

Source: US EPA

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