国产热热热精品,亚洲视频久久】日韩,三级婷婷在线久久,99人妻精品视频,精品九热人人肉肉在线,AV东京热一区二区,91po在线视频观看,久久激情宗合,青青草黄色手机视频

Science and Health

Sperm may be harmed by exposure to BPA: study

(Xinhua)
Updated: 2010-08-04 13:43
Large Medium Small

WASHINGTON -- In one of the first human studies of its kind, researchers have found that urinary concentrations of the controversial chemical Bisphenol A, or BPA, may be related to decreased sperm quality and sperm concentration, the University of Michigan said Tuesday in a statement.

The new study suggests that more research should focus on BPA and health effects in adults, says John Meeker, assistant professor of Environmental Health Sciences at the University of Michigan School of Public Health. Meeker is the lead author of the study, along with Russ Hauser, professor at Harvard School of Public Health.

Related readings:
Sperm may be harmed by exposure to BPA: study Jennifer Aniston says no to sperm banks
Sperm may be harmed by exposure to BPA: study Dead sperm whale fished out in Philippine bay
Sperm may be harmed by exposure to BPA: study Human sperm gene unchanged for 600 million years

Meeker and Hauser recruited 190 men through a fertility clinic. All gave spot urine samples and sperm samples the same day. Subsequently, 78 of the men gave one or two additional urine samples a month apart. Researchers detected BPA in 89 percent of the urine samples.

Researchers measured sperm concentration, sperm motility, sperm shape and DNA damage in the sperm cell.

"We found that if we compare somebody in the top quartile of exposure with the lowest quartile of exposure, sperm concentration was on average about 23 percent lower in men with the highest BPA, " Meeker said.

Results also suggested a 10 percent increase in sperm DNA damage.

However, the researchers are quick to point out that these results are preliminary and more study is needed. Several studies have documented adverse effects of BPA on semen in rodents, but none are known to have reported similar relationships in humans.

BPA is a common chemical that's stirred much controversy in the media lately over its safety. Critics say that BPA mimics the body's own hormones and may lead to negative health effects. BPA is most commonly used to make plastics and epoxy resins used in food and beverage cans, and people are exposed primarily through diet, although other routes are possible. More than 6 billion pounds of BPA are produced annually in the United States.

临颍县| 天祝| 雅江县| 九寨沟县| 佛山市| 交口县| 纳雍县| 新巴尔虎右旗| 富锦市| 望谟县| 宝应县| 华蓥市| 康保县| 巫溪县| 新晃| 长葛市| 噶尔县| 象山县| 稻城县| 慈溪市| 开阳县| 高阳县| 安徽省| 烟台市| 蒙山县| 江川县| 太保市| 缙云县| 南昌县| 班戈县| 华池县| 花莲县| 翁牛特旗| 西华县| 恩施市| 广宁县| 夹江县| 福泉市| 甘洛县| 台东县| 荃湾区|