Stratospheric ozone depletion, UV radiation and health

It has been recognized for several decades that the release of chlorofluorocarbons and other atmospheric pollutants depletes stratospheric ozone, which in turn increases human exposure to ultraviolet radiation, causing skin cancer and cataracts.
The recognition of direct effects on human health effects was a major stimulus to the Montreal Protocol, which acts to reduce emissions of pollutants that weaken the ozone layer. Although this international agreement is proving highly effective in reducing risks in the long term, UV radiation remains a health hazard.
The World Health Organization, and partner organizations - through the Intersun project - have developed and promote the UV Index, a tool to inform and educate the public about sun protection.