New research suggests that so-called endocrine-disrupting chemicals in many foods and household items put the whammy on human sperm cells, potentially impairing a man's fertility.
"For the first time, we have shown a direct link between exposure to endocrine-disrupting chemicals from industrial products and adverse effects on human sperm function," study co-author Dr. Niels E. Skakkebaek, a professor at Copenhagen University Hospital in Denmark, said in a written statement.
For the study, an international team of researchers used a newly developed bioassay to gauge the impact of endocrine disruptors on human sperm.
What did the scientists find? About one-third of the chemicals showed adverse effects in sperm, including ultraviolet-filtering chemicals like 4-methylbenzylidene camphor (4-MBC) used in some sunscreens; the antibacterial agent Triclosan, which is used in some toothpaste; and di-n-butylphthalate (DnBP) used in some glue products.
Endocrine disruptors were linked to an increase in sperms' calcium levels, which may sabotage their swimming behavior and trigger the premature release of enzymes that enable sperm cells to fuse with an egg cell.
That's not all. In the female reproductive tract, endocrine disruptors might cause problems by drowning out the hormonal signal that sperm cells usually follow to find the egg.
“In my opinion, our findings are clearly of concern as some endocrine-disrupting chemicals are possibly more dangerous than previously thought," Dr. Skakkebaek told The Independent. "However, it remains to be seen from forthcoming clinical studies whether our findings may explain reduced couple fertility which is very common in modern societies."
The study was published online in the journal EMBO Reports on May 9, 2014.