NOTTINGHAM, United Kingdom — Chemicals found in common household products may be damaging sperm quality in men and dogs, a new study finds.
Researchers at the University of Nottingham say that one of the chemicals, diethylhexyl phthalate (DEHP), is often found in carpets and flooring, upholstery, wires, toys, and even in clothing. DEHP is a substance added to products to increase plasticity or flexibility. The other chemical, polychlorinated biphenyl 153 (PCB), is banned in countries across the globe after being widely used in electronics and machinery in the 1970s. But PCBs are still found in the environment — and consequently in the food chain — thanks to leaks or products that were improperly discarded or stored.
The study is the first to test the effects of the contaminants on both human sperm and dog sperm. The authors had previously discovered that sperm quality in domestic dogs had significantly declined in recent decades — numbers that tend to mirror research on declining fertility in men. Those studies report up to a 50% global reduction in sperm quality over the past 80 years.
Researchers exposed sperm samples from nine men and 11 stud dogs living in the UK to both chemicals, and found similar levels of damage in both species. The authors were sure to test the samples using levels of exposure comparable to what one might encounter in everyday life.
“In both cases and in both subjects, the effect was reduced sperm motility and increased fragmentation of DNA,” says co-author Rebecca Sumner in a university release.
Researchers say the findings raise new red flags when it comes to chemical pollutants within the home, as well as in locations that might have greater concentrations of PCBs in the environment.
“This new study supports our theory that the domestic dog is indeed a ‘sentinel’ or mirror for human male reproductive decline and our findings suggest that man-made chemicals that have been widely used in the home and working environment may be responsible for the fall in sperm quality reported in both man and dog that share the same environment,” adds lead researcher Richard Lea, an associate professor and reader in reproductive biology at the School of Veterinary Medicine and Science at the university.
Future studies, the authors say, should hone in on specific regions around the world that could be more detrimental to fertility in men and dogs because of these pollutants.
The study is published in the journal Scientific Reports.