The world is experiencing a quiet but accelerating collapse in male fertility, according to an article published Tuesday in the journal Human Reproduction Update.
The study found that sperm counts fell by more than 51 percent between 1973 and 2018. And while sperm counts have been declining for decades, the decline seems to be accelerating.
“I think it’s a crisis that we [had] better act now, before it reaches a tipping point that may no longer be reversible,” lead author Hagai Levine of the Hadassah Braun School of Public Health at the Hebrew University of Jerusalem told The Guardian.
Levine added to The Times of Israel that the findings “serve like a canary in a coal mine. We have a serious problem that, if left unsolved, could jeopardize the survival of humanity.”
The rate of decline since 2000 is striking, the study found, with an observed 2.64 percent annual drop in sperm counts per milliliter of semen — more than twice the drop since 1978, according to The Guardian .
While the reasons for the decline are unclear, endocrine-disrupting chemicals found in thousands of everyday objects could be a major factor, co-author Shanna Swan of the Icahn School of Medicine told the Financial Times.
These compounds — found in everything from personal care products to food packaging — have particularly serious effects on reproductive function, Swan noted. She specifically mentioned phthalates and bisphenols, compounds used as linings in products such as water bottles and takeout containers.
The joint study by Levine and Swan builds on existing findings that have linked environmental chemicals to persistent declines in sperm count.
A 2021 Danish study listed chemicals found in or derived from fossil fuels as possible culprits, as The Hill reported.
Potentially harmful chemicals from such sources “were found in samples of blood, urine, semen, placenta and breast milk from all people studied,” the study said.
“It is well known that these chemicals have become part of our tissues and fluids,” the authors added. “We know they can pose a threat to wildlife. Unfortunately, too little has been done to expose their role in humans.”
Plastic derivatives such as bisphenol A (BPA) – often added to food and drink packaging – have also been linked to declining male fertility and birth defects.
Many potentially toxic chemicals “reach us through food,” Andreas Kortenkamp, a professor at Brunel University London, said in June.
“A lot of bisphenol A intake is through milk,” he added. “The liners of milk cartons and canned foods, for example the tomato cans, leak BPA into the product.”
The Israeli study comes as the world’s population recently hit 8 billion. Still, birth rates are broadly falling — meaning it will take longer to add the next billion than the last.