(NaturalNews) Exposure to the ubiquitous industrial chemical bisphenol A (BPA) has once again been linked to decreased sperm health, this time in humans, in a study conducted by researchers from Kaiser Permanente and published in the journal Fertility and Sterility.
The findings are of particular concern because symptoms were found at very low exposures, and because BPA is so widespread.
"BPA, a plastic and resin ingredient used to make a wide variety of plastic goods and to line metal food and drink cans (ever wonder how those canned contents slip so easily out and onto your plate, or into your bowl or mouth?), is a toxin associated with birth defects of the male and female reproductive systems," write Brenda Watson and Leonard Smith in their book The Detox Strategy.
"BPA is commonplace -- found in copious brands of fruit, vegetables, soda, and other frequently eaten canned goods. It migrates from the can or plastic into the contents, which are then ingested."
BPA is also found in coatings of electronics, in paper receipts and a variety of other common products.
In the current study, researchers followed 218 workers at a Chinese epoxy resin factory for five years, testing urine samples for BPA and measuring sperm concentration, count, motility, morphology and vitality.
They found that men with the highest BPA concentrations in their urine were four times more likely to have low sperm count and twice as likely to have low sperm motility as men with no detectable BPA levels. Men with high concentrations also had significantly lower sperm concentration and vitality.
The effects were found at levels common among the general population.
"This study counters the argument that only highly exposed populations are affected," researcher De-Kun Li said. "You can be exposed from the workplace. You can be exposed from consumer products. It doesn't really matter."
"For the past few decades, sperm counts have been declining [and] this might be related to exposures to endocrine-disrupting chemicals such as BPA," said reproductive physiologist Gail Prins of the University of Illinois, who was not involved in the study.