ABSTRACT
Depletion of the ozone layer has become a topic of considerable importance and concern. Evidence indicates that the concentration of stratospheric ozone has already decreased globally over the past several years (Stolarski et al., 1991) and additional decreases are to be expected over the coming decades. A further depletion of the ozone layer would lead to an increase in the amount of UV radiation; UV radiation can be divided into UV-A (wavelengths 315–400 nm), UV-B (280–315 nm), and UV-C (100–280 nm). If short-wave UV radiation is absorbed by various components of plant and animal cells, several essential molecules are damaged, most notably the DNA which carries the genetic instructions for the synthesis of proteins, fundamental to a proper functioning of the cell. As all living organisms are built up of cells, solar UV radiation may be expected to have a widespread and fundamental effect on our biosphere, including direct effects on man (de Gruijl & van der Leun, 1993). The adverse effects, particularly of UV-B radiation, on human health are: sunburn, skin cancer, skin ageing, cataracts, and a probable impairment of human resistance to infectious diseases. The effects of excessive levels of UV-B on agriculture and ecosystems are: reduced crop yields, damage to phytoplankton, and adverse effects on aquatic food chains (UNEP, 1994).
