Decline in male births in U.S. and Japan may be caused by contamination

This is one of those cases where if you happen to be watching the news on a specific topic you begin to see trends.

Over the past several years I've read several articles about the possible connection between exposure to certain pollutants and lower male birth rates. This includes stories of entire communities that are in close proximity to certain types of industry or contamination that are experiencing very low male birth rates.

These are just a few of the articles:

• 09-Apr-2007 - Pollution: Where have all the baby boys gone?
• 18-Sep-2005 - Study: Fewer boys near chemical plants
• 18-Jul-2005 - Examining Environmental Factors in Sex Ratio
• 27-Apr-2007 - Pollutant affects sex chromosome
• 10-May-2006 - Sex-bending chemicals meddling with evolution
• 05-May-2000 - Where the boys aren't: Industrial nations puzzle over decline in male birth ratio.
• 24-May-2000 - DECLINING MALE BIRTHRATE BAFFLING SCIENTISTS
• 01-Mar-2003 - PCBs'' legacy: fewer boys. (Endocrine Disruptions).
• 01-Jan-2002 - Where the Boys Aren't: Dioxin and the Sex Ratio.

It makes you wonder if the problem will end up being the solution to the problem . . .

Here's the most recent article:

A study published in this week’s online edition of Environmental Health Perspectives reports that during the past thirty years, the number of male births has decreased each year in the U.S. and Japan. In a review of all births in both countries, the University of Pittsburgh-led study found significantly fewer boys being born relative to girls in the U.S. and Japan, and that an increasing proportion of fetuses that die are male. They note that the decline in births is equivalent to 135,000 fewer white males in the U.S. and 127,000 fewer males in Japan over the past three decades and suggest that environmental factors are one explanation for these trends.

“The pattern of decline in the ratio of male to female births remains largely unexplained,” said Devra Lee Davis, Ph.D., M.P.H., lead investigator of the study, director of the University of Pittsburgh Cancer Institute’s Center for Environmental Oncology and professor of epidemiology, University of Pittsburgh Graduate School of Public Health. “We know that men who work with some solvents, metals and pesticides father fewer baby boys. We also know that nutritional factors, physical health and chemical exposures of pregnant women affect their ability to have children and the health of their offspring. We suspect that some combination of these factors, along with older age of parents, may account for decreasing male births.” More . . .