It sometimes takes an environmental catastrophe to demonstrate a stark cause and effect.
One such example was the explosion at the Chernobyl nuclear power plant near Kiev in April 1986, which released radioactive materials over Belarus and the Ukraine.
Since then, doctors have noted a 12-fold increase in the rate of thyroid cancer among women in the Belarus region. The increase has been greatest in young females aged 14 years or lower, who have experienced a 30-fold increase in the disease since the explosion.
Between 1980 and 1986, there were 0.15 cases per 100,000 girls aged below 14 years, but this increased to 43.84 cases between 1997 and 2001.
(Source: International Journal of Epidemiology; website: http://www.ije.oupjournals.org).