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Helping people reduce their risks of skin cancer and cataract

A practical guide for using the global solar UV index

Overexposure to solar ultraviolet (UV) radiation is responsible for two major public health problems: skin cancer and cataract.

Between 2 and 3 million non-melanoma skin cancers and at least 132,000 malignant melanomas occur globally each year. There has been a significant increase in the incidence of skin cancers since the 1970s. A changing lifestyle and sun-seeking behaviour are responsible for much of the increase in skin cancers. Depletion of the ozone layer, which provides a protective filter against UV radiation, aggravates the problem.

"Very simple and inexpensive protection measures, such as wearing a shirt, hat, sunglasses and sunscreen and seeking shade during midday hours can significantly reduce the risk of these conditions," reports Intersun, WHO's Global UV Project. "Such measures could eliminate up to 70% of skin cancers in several countries."

Sun exposure may also be responsible for more than 2 million cases of blindness due to cataract worldwide. Furthermore, UV radiation may impair immune function which could enhance the risk of infections and limit the efficacy of vaccination programmes.

Sun protection programmes to raise awareness of the health hazards of UV radiation and to encourage people to adopt protective measures are urgently needed.

An integral part of such programmes is the Global Solar UV Index (UVI), an educational tool, developed in 1997 through an international effort by WHO in collaboration with the United Nations Environment Programme (UNEP), the World Meteorological Organization (WMO), the International Commission for Non-Ionizing Radiation Protection (ICNIRP), and the German Federal Office for Radiation Protection. This simple measure of UV radiation levels at the Earth's surface indicates the potential for skin damage and alerts people to take appropriate protective actions.

Many countries have been using the UVI to promote sun protection - along with the weather forecast in newspapers, TV and radio. However, people often did not fully understood its meaning or usefulness, and the symbols, colour codes and protection messages greatly differed between countries, creating confusion.

Intersun is introducing an internationally agreed communication concept to harmonize reporting of the UVI worldwide and to improve its use as an educational tool. The new concept is published in a WHO booklet: "Global Solar UV Index - A Practical Guide".

UVI values are grouped into exposure categories of low, moderate, high, very high and extreme with corresponding colour codes. Simple icons indicate the appropriate sun protective behaviour. Ready-made materials for UVI reporting are available in a graphics package which will soon be downloadable from Intersun's web site.

The practical guide also provides basic facts about UV radiation exposure, its determinants and health effects, the use of the UVI, and options for public education messages for different target audiences and settings.

For more information contact:

Eva Rehfuess
Telephone: (+41 22) 791 4979
Fax: (+41 22) 791 1383

Mr Gregory Hartl
Telephone: +41 (22) 791 4458
Mobile phone: +41 (79) 203 6715