Workers exposed to high levels of the chemical BPA were more likely to have erectile dysfunction and other sexual problems than men not exposed to the chemical, a new study has found.

The research, appearing in the latest issue of the journal Human Reproduction, studied 634 Chinese factory workers over five years, comparing men whose workplaces had high levels of BPA to those who had none. Workers in the factories with BPA had four times the risk of erectile dysfunction and seven times more risk of ejaculation problems, researchers from Kaiser Permanente found.

While other studies have linked high BPA levels to sexual dysfunction in animals, the authors say this study is the first in humans to study BPA's impact on men's reproductive system.

BPA, or bisphenol-A, use is widespread and the chemical is present in the urine of some 92 percent of Americans, the study states. Manufacturers use BPA to make the linings of food and beverage bottles and cans because it's durable, makes plastics harder and can withstand high temperatures.

Whether it's safe remains controversial. The government has been debating BPA, while consumer groups push hard for bans of the chemical. The Food and Drug Administration is expected to release findings from a long study on the issue later this month. Meanwhile, studies continue to question the safety of BPA. Last week, we told you about a Consumer Union report that found measurable levels of the chemical in canned foods.

In the study on sexual problems linked to BPA, the authors acknowledge more study is needed on the topic. For starters, men in the study were exposed to BPA levels 50 times higher than what the average man faces in the States. But for now, they say, given the widespread use of BPA their finding should be considered as the debate continues over its safety.