The researchers found that being a marijuana smoker at the time of diagnosis was associated with a 70 percent increased risk of testicular cancer. The risk was particularly elevated (about twice that of those who never smoked marijuana) for those who used marijuana at least weekly and/or who had long-term exposure to the substance beginning in adolescence.
Chronic marijuana exposure has multiple adverse effects on the endocrine and reproductive systems, primarily decreased sperm quality. Other possible effects include decreased testosterone and male impotency. Because male infertility and poor semen quality also have been linked to an increased risk of testicular cancer, this further reinforced the researchers' hypothesis that marijuana use may be a risk factor for the disease.
clipped from: www.elements4health.com 