Are Melanoma Incidence and Mortality Reasonably Consistent with a Major Role for Solar-Ultraviolet Radiation?
Earlier we set down the general outlines of the pattern of evidence to be expected if total UV dose were not the sole critical factor in solar-related cancers, i.e., UV-B might be a contributing but not sole cause, and pointed out that melanoma behavior fitted that pattern. We have now reviewed the details of the evidence concerning melanoma and ought to inquire further as to the reasonableness of a major role for solar-UV radiation in melanoma. Ozone depletion will result not only in an increase in UV-B flux but also in a shift to shorter wavelengths that reach the earth. If the action spectrum of human skin cancers is similar to the action spectrum for DNA damage, a nonlinear and disproportionately higher increase of these tumors would be anticipated. That is, a given percentage increase in solar UV-B should yield a higher percentage increase in melanoma. If the action spectrum for either form of human skin cancer is not sensitive in the shorter wavelengths, then a lesser effect of o
