SAN FRANCISCO--A pollutant called octylphenol found widely in the environment severely damages the reproductive systems of adult male rats, according to research presented here this week at the American Society for Cell Biology's annual meeting. The results may heighten the concerns of some scientists that octylphenol, an ingredient in textile manufacturing and other industrial processes, and related chemicals may contribute to fertility problems in humans.
Cell biologists Fredric Boockfor and Charles Blake of the University of South Carolina Medical School injected rats three times a week with 20 milligrams of octylphenol--an amount comparable to what has been found in the fatty tissue of fish in some polluted rivers. The scientists saw "a roughly fourfold increase" in sperm abnormalities and a 50% decrease in sperm count after 1 month of treatment, Blake says. After 2 months, the rats' reproductive organs were shriveled up and unable to produce any sperm at all.
The researchers say their dramatic results--and those from other labs linking octylphenol with reproductive problems in marine life and development problems in rat embryos--bolster concerns that octylphenol, dioxin, polychlorinated biphenyls (PCBs), and other hormonelike chemicals might be responsible for a possible decline in fertility rates in developed countries. According to estimates from environmental groups, about 300,000 tons of octylphenol and related compounds are dumped in U.S. waterways every year, where they are absorbed by algae and other plants and concentrate in the fatty tissue of animals. "Things like this could be contributing to the decline in human reproductive potential," Boockfor says.
The purported decline in human fertility is a matter of debate among scientists, notes Dolores Lamb, a urologist at Baylor College of Medicine in Houston. But she says these findings should lead to well-designed studies to assess the fertility of human males.