Overexposure to certain environmental elements such as heat, toxins and chemicals can reduce sperm production or sperm function. Specific causes include:

  • Industrial chemicals.Extended exposure to benzenes, toluene, xylene, pesticides, herbicides, organic solvents, painting materials and lead may contribute to low sperm counts.
  • Heavy metal exposure.Exposure to lead or other heavy metals also may cause infertility.
  • Radiation or X-rays.Exposure to radiation can reduce sperm production, though it will often eventually return to normal. With high doses of radiation, sperm production can be permanently reduced.
  • Overheating the testicles.Frequent use of saunas or hot tubs may temporarily lower your sperm count. Sitting for long periods, wearing tight clothing or working on a laptop computer for long stretches of time also may increase the temperature in your scrotum and slightly reduce sperm production. The type of underwear you wear is unlikely to make a significant difference in male fertility.