There are plenty of studies about the effects of bisphenol A on animals, but it’s always challenging to study the effects of a ubiquitous chemical in humans. Findings from a new epidemiologic study helps fill in some of the gaps in understanding BPA’s effects on humans.

The NIOSH-funded study conducted by the Kaiser Foundation Research Institute followed 634 male workers who were exposed to high levels of BPA at Chinese factories, and compared their sexual health to that of male counterparts whose workplaces did not involve the chemical. The Washington Post’s Lindsey Layton describes the results:

The men handling BPA were four times as likely to suffer from erectile dysfunction and seven times as likely to have difficulty with ejaculation, said De-Kun Li, a scientist at the Kaiser Foundation Research Institute  

The workers studied did not have to spend years in the factory to develop problems – sexual dysfunction began in new workers after just months on the job, Li said.

The workers had levels of exposure to BPA that were 50 times what an average U.S. man faces. But the findings raise questions about whether exposure at lesser levels can affect sexual function, Li said. “This was a highly exposed group, and we see the effect,” he said. “Now, we have to worry about lower-level exposure.”