Prenatal exposures affect sperm later

In Taiwan, a 1979 industrial accident known as Yu Cheng contaminated rice oil with huge quantities of polychlorinated biphenyls (PCBs) and furans. Both are types of dioxinlike compounds.

Children born to women who had eaten much of the tainted oil exhibited a host of developmental problems (SN: 11/11/95, p. 310). A new follow-up study has found hints that fertility will be impaired in young men who had received substantial exposure to the toxic pollutants while in the womb.

Because animal studies had shown that dioxinlike pollutants can alter reproductive development (SN: 5/30/92, p. 359), an international team of researchers decided to scout for reproductive changes in sons of Yu Cheng victims. Yueliang Leon Guo of National Cheng Kung University Medical College in Taiwan and his coworkers compared semen from the 12 reproductively mature young men in this group with sperm from 23 unexposed men who were also around 17 years old.

Contrary to the researchers’ expectation, there was no difference in sperm counts between the groups, notes study coauthor George H. Lambert, director of Rutgers University’s Center for Child and Reproductive Environmental Health in Piscataway, N.J.

“A second surprise,” he says, “was our finding of changes in sperm motility.” Fewer sperm from the Yu Cheng sons were fully active, and fewer of those that were active moved appropriately, the team reports in the Oct. 7 Lancet. Also, sperm from Yu Cheng sons were less capable than those from unexposed men of penetrating hamster-egg cells, a standard fertility assay.

Janet Raloff is the Editor, Digital of Science News Explores, a daily online magazine for middle school students. She started at Science News in 1977 as the environment and policy writer, specializing in toxicology. To her never-ending surprise, her daughter became a toxicologist.

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