Study: BPA exposure may lead to thyroid hormone changes in men

An international group of researchers from the Peninsula Medical School and the University of Exeter recently identified changes in sex hormones that are associated with bisphenol A (BPA) in men. BPA, which has also been associated with thyroid hormone disruption, is a chemical commonly used in food and drink containers.

During the study, which was published in the latest issue of Environmental Health Perspectives, researchers measured the amount of BPA excreted per day in urine samples of 715 Italian men aged between 20 and 74 years old. The scientists examined statistical associations between the amount of BPA exposure and serum testosterone concentrations.

The average BPA exposure level in this study population was slightly higher than recent comparable estimates for the U.S. population. However, the study found that higher exposure was statistically associated with endocrine changes in men, specifically small increases in levels of testosterone.

"This is just the first step in proving that at 'ordinary' exposure levels, BPA might be active in the human body," said David Melzer, professor of epidemiology and public health at the Peninsula Medical School. "This new evidence does justify proper human safety studies to clarify the effects of BPA in people."

BPA is used in polycarbonate plastic products such as refillable drinks containers, some plastic eating utensils and many other products in everyday use. The main source of BPA in people is thought to be from residues in food. It is detectable in the bodies of more than 90 percent of the population.