Pollution keeps falling on their heads


By Andy Coghlan WALKING under high-voltage overhead power lines could treble your exposure to airborne pollutants, warns Denis Henshaw of the University of Bristol. His studies with model human heads suggest that the cables attract pollutants trapped in fine water droplets. Henshaw compared 1000 measurements directly beneath the power lines with a similar number at distant sites, and found that between 1.5 and 3 times as many aerosol particles landed on heads he placed under the cables. In previous experiments, Henshaw showed that the aerosol particles can contain chemical and radioactive pollutants (New Scientist, 17 February 1996, p 4), plus bacteria and viruses. The powerful electrostatic fields generated by the cables polarise droplets of water, which are then attracted to the cables. Pollutants such as sulphur dioxide banging into the cables also become ionised by losing electrons. “That’s the hissing you hear near power lines,” says Henshaw. The ions then dissolve in the water droplets. Henshaw speculates that these ions might also cause disease by being inhaled and retained in the lungs. He has no direct proof that there is a health problem, but quotes a study by Beverly Cohen of the New York University Medical Center. In 1998,
  • 首页
  • 游艇租赁
  • 电话
  • 关于我们