By Steven ReinbergHealthDay Reporter
WEDNESDAY, Nov. 22, 2017 (HealthDay News) -- Men who have trouble conceiving may have the air they breathe to blame, a new study by Chinese researchers suggests.
Microscopic particles in the air called particulate matter (PM2.5) may affect the quality of sperm, which in turn can make it difficult to fertilize a woman's egg, the researchers said.
PM2.5 stands for particulate matter with a diameter 2.5 micrometers or less. That's about 3 percent of the diameter of a human hair.
"Air pollution is associated with a significant drop in normal sperm shape and size, which may result in a significant number of couples with infertility," said lead researcher Xiang Qian Lao. He is an assistant professor in the School of Public Health and Primary Care at the Chinese University of Hong Kong.
Lao cautioned, however, that this study can't prove that PM2.5 causes the damage to sperm, only that the two are associated.
"You cannot conclude it is a causal relationship in this study, but existing evidence from toxicology and other studies support that the relationship is potentially causal," he said.
Exactly how air pollution might affect sperm isn't ...