Ever wonder how it was physically possible for your great-grandparents to have like 10 kids? Well, sperm was better. No, seriously. Apparently sperm just isn't doin' it's damn thing like it used to.
While there are regional variations, sperm counts and quality have, by and large, been declining over the past 50 years or so. One 2013 study of more than 26,000 French men, for example, found that sperm concentrations have dropped by nearly 2 percent each year from 1996 to 2005. And other male reproductive problems, like testicular cancer and genital birth defects, are on the rise.
And we might finally know why:
A new study soon to be published in the journal PLOS Genetics suggests that bisphenol A (BPA)—an endocrine disruptor found in many plastics, can linings and receipts, and which mimics the effects of estrogen—may play a role in this decline in male fertility.
Oh damn dudes gotta stop touching plastic, can linings and receipts????? Tall order.
In the study, researchers exposed several different types of mice to low concentrations of BPA at birth, for a short period of time. Once the mice were sexually mature, the scientists examined the animals' testes and measured sperm count. In exposed males, sperm count was significantly lowered in two out of three mice strains tested, says study author
Patricia Hunt, an expert on BPA at Washington State University. The one strain unaffected by BPA, an inbred variety, appears to have developed an unusual resistance to the chemical that wouldn't be expected in other mammals like humans, she adds.
Moral of the story, mice are going to outlive us all.
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