The good news is that the ozone hole over Antarctica is slowly healing, thanks to controls on ozone-depleting substances that were once widely used in products such as refrigerators and aerosol cans. Stratospheric ozone protects us from harmful ultraviolet radiation that can cause problems such as skin cancer and crop damage.

For all the problems greasy hair might bring, there's at least once upside: lessened exposure to ozone. In a decidedly odd, though fruitful study, University of Missouri researchers Glenn Morrison and Lakshmi Pandrangi measured the ozone levels surrounding samples of washed and unwashed hair over the course of a day. Dirty hair absorbed seven times the amount of ozone.

In 1974, chemists F. Sherwood Rowland and Mario Molina warned that chlorofluorocarbons (CFCs), widely used as refrigerants, were destroying the ozone layer.

Using a spectrometer, British researchers discovered the ozone hole in the lower stratosphere over Antarctica in the mid-1980s.




The hole swells and contracts; it grew largest in Sept. 2000, spanning about 17.5 million square miles.