There's been a lot of talk about how pollution suppresses testosterone, here a study that shows how it (indirectly) increases it. From the Daily Mail:
Researchers at Zhejang University, in Hangzhou, China, looked at a class of pesticides called pyrethroids that account for more than 30 percent of global insecticide use. 'Residues of this pesticide are often found in vegetables, in milk and in baby food,' said lead investigator Dr Jing Liu, an associate professor at Zhejiang University. Evidence of recent exposure to the chemical appears in human urine as a metabolite, or molecule, called 3-phenoxybenzoic acid (3-PBA). The metabolite is known to be an endocrine-disrupting chemical that interferes with the body's hormones. The researchers studied more than 460 Chinese boys between the ages of 9 and 16. They found that a 10 percent increase in 3-PBA was associated with a four percent increase in the boys' levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).