Applying sunscreen to prevent skin cancer

Sunbathers apply sunscreen on Scarborough Beach in western Australia in an attempt to thwart the cancerous effects of the sun`s UV rays. Skin cancers are often detected earlier than other cancers since they can reveal themselves externally in the form of moles or enlarged birthmarks. The effectiveness of sunscreen is debatable, however: critics say it can prevent burns but does little to stop cancer, and sunscreen is often made with chemicals that could increase risk of other forms of cancer.