From Sandra Bennett, Northwest Center for Health and Safety
Your story about the rapidly declining sperm count of British men says that researchers at the University of Aberdeen could find no specific cause for this phenomenon (10 January, p 6). Apparently the researchers suggested that water-borne pollutants, tight underpants or working in a warm environment might be to blame.
Based on other more recent studies, we suspect that the real culprit is far more likely to be increased use of cannabis. As the UK has removed more and more restrictions on marijuana use, its popularity has escalated and users abound. The impact of cannabis on sperm and egg cells has been known for 20 years, and more recent studies show that cannabis use contributes to premature death of these reproductive cells.
The marijuana connection seems far more likely than tight underpants. It might be a good idea to go back to the database and find out which men were using cannabis during the period covered by the study.
Portland, Oregon, US
