Too much pollution can damage sperm.
In the first study, published by Rebecca Sokol and colleagues, ozone seemed to be one reason for the change. During a study of the quality of semen from local sperm donors, it was discovered that sperm counts were lower in men from areas where ozone levels were high during the previous 90 days. Researchers say that it would take that long for new sperm to develop.
The study also took into account effects of temperature and seasonal changes. Airborne particulates, nitrogen oxides, and carbon monoxide were not linked with lower sperm counts.
In the second study, American and Czech researchers examined seven semen samples from each of 26 men who live in a polluted Czech region.
They took samples once every September for three years for most of the men and as many as four samples during the winter for the others. In the winter, pollution levels can almost double in that region.
Most of the winter samples contained levels of particulate matter, nitrogen oxides, and sulfur dioxide that exceeded common regulatory limits. The samples had more fractured DNA than the September samples.
(Sources: Environmental Health Perspectives 2006;114; Human Reproduction, October 2005.)
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|Publication:||Nutrition Health Review|
|Article Type:||Brief article|
|Date:||Jun 22, 2005|
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