Article overstates study's findings about BPA and testosterone in men.

Capitalizing on two hot scientific topics – environmental chemicals and testosterone – Shari Roan’s recent Los Angeles Times article boldly claims that new research shows that "chemicals in plastics can increase testosterone in men." Unfortunately, while that headline and the opening paragraph are likely to grab readers' attention, it's an overstatement of the actual published research, in which the authors were careful not to draw any such conclusions.

Instead of saying that BPA causes increased testosterone levels, the coverage would have been more accurate had the reporter stuck to her later statement that "men who had high levels of the chemical bisphenol A also had higher testosterone levels compared to men with lower levels of the chemical in their bodies."

Bisphenol A (BPA) is found in polycarbonate plastics, epoxy resins, some carbonless papers and other products. It is estrogenic, which means it can disrupt hormone levels, and may contribute to myriad health concerns ranging from metabolic disorders to fertility issues.

The researchers looked at serum levels of reproductive hormones – such as testosterone and estrogen – in relation to levels of BPA in a group of more than 700 Italian adults. They found that among the men studied, higher levels of BPA were associated with higher total testosterone levels. The authors were careful not to read any further as to cause and effect into the intriguing finding. Unlike an experiment with animals, the researchers could not give the participants BPA and then see how their hormone levels change over time. As a result, they cannot draw any conclusions as to whether the BPA actually caused the high tesosterone levels.

While it is correct to say that the results show that elevated BPA levels were linked to elevated testosterone levels in this study, to draw the conclusion that one causes the other is clearly an overstatement that the authors of the study were careful to avoid. It is possible, for instance, that elevated levels of both chemicals were, in fact, associated with some other factor, such as diet or metabolism. To better understand just how BPA exposure might affect reproductive hormone levels - and whether the relationship is, in fact, causal -  future studies and experiments of different types are needed.