Ultraviolet irradiation of human body sites in relation to occupation and outdoor activity: field studies using personal UVR dosimeters

Effects of Arctic ozone depletion and snow on UV exposure in Finland

The increase in the UV exposure of the Finnish population associated with the combined effects of ozone depletion and snow reflection was studied with the aid of theoretical calculations based on Green's clear sky UV model. A simple formula was utilized to transform horizontal irradiances to vertical irradiances averaged over 360 degrees azimuth angle. The model was verified with spectral and broadband measurements. The difference between the theoretical and measured UV radiation falling to horizontal surfaces was in most cases less than +/- 10%, and the additional error to theoretical vertical irradiances was less than +/- 10%. The calculations show that the annual horizontal doses in Helsinki (60.2 degrees N, 25 degrees E) are about 35% higher than in Saariselkä (68.4 degrees N, 27.5 degrees E), but the difference is only 16% for vertical doses owing to the stronger contribution to vertical (facial) surfaces of the reflection of UV from snow. At Saariselkä, the maximum vertical irradiance at the end of April approaches the midsummer values. The ozone depletions up to 40% in February and March 1992 had no significant effect on the annual doses because the total ozone returned to normal before the UV increased to biologically significant levels.

Stratospheric ozone depletion and the risk of non-melanoma skin cancer in a British population

Quantitative estimation of the increased risk of non-melanoma skin cancer (NMSC) in British people that may result from depletion of the stratospheric ozone layer is given for the present generation of British people. For adults alive today continuing ozone depletion at current rates is predicted to result in a relatively small additional lifetime risk (< 5%) of NMSC, assuming no changes in climate, time spent outdoors, behaviour or clothing habits. The lifetime risk incurred by today's children, however, is 10%-15% greater than expected in the absence of ozone depletion. However, if the production and use of substances which deplete ozone are reduced, as expected under the current provisions of the Montreal Protocol, the increased lifetime risk of skin cancer is likely to be less than this estimate. These predicted increases in risk, resulting from greater solar ultraviolet exposure, can be offset by adopting changes to behaviour during the summer months which may involve spending less time outdoors, wearing appropriate clothing including wide-brimmed hats, applying topical sunscreens, or a combination of these.