Public Release: 1-Apr-2017
Pyrethroid pesticide exposure appears to speed puberty in boys
The Endocrine Society
Environmental exposure to common pesticides may cause boys to reach sexual maturity earlier, researchers have found. They will present their study results Saturday at the Endocrine Society's 99th annual meeting in Orlando, Fla.
Previous research shows that early puberty increases the risk of diseases in adulthood, for example, testicular cancer in men and breast cancer in women. Early puberty also can stunt growth and cause behavioral problems.
The class of pesticides studied, pyrethroids, accounts for more than 30 percent of global insecticide use, said Jing Liu, Ph.D., lead investigator and an associate professor at Zhejiang University in Hangzhou, China. These chemicals are known endocrine-disrupting chemicals that interfere with the body's hormones.
"We recognize pyrethroids as a new environmental contributor to the observed trend toward earlier sexual maturity in boys," Liu said.
Pyrethroids are used indoors and outdoors to kill mosquitoes and other insects, and are sprayed on crops. Humans likely receive most of their exposure to pyrethroids from food and residential use.
In a study of 463 Chinese boys ages 9 to 16 years, Liu's research team found that a 10 percent increase in 3-PBA was associated with a 4 percent increase in the boys' levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Both these hormones spur production of testosterone in males.