Nexus - 0205 - New Times Magazine-pages

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SUNGLASSES & MELANOMA IS THERE A CONNECTION? CONNECTION? THERE melanoma is to avoid the sun. Consistent with this disposition, we are exhorted either to stay out of the sun or should we have to go in it, to arm ourselves with sunscreens and sunglasses as the best protection against melanoma. Contrary to the orthodox position on this subject, we submit that little more than half of the presented cases of melanoma can be explained solely as 'sun-caused'. The conventional interpretation has no coherent hypothesis to offer by way of explaining the remainder of these cases, some of which involve either minimal exposure to sunlight or melanomas in parts of the body not exposed to the sun. On the basis of a multi-disciplinary survey of the world literature, it is our view that a number of environmental factors, including exposure to artificial light sources and electro- magnetic radiation contribute to the unabated rise in the incidence of melanoma. We have argued elsewhere for these views, and shall not repeat the arguments here.’ The thesis we propose to defend in this paper is that the wearing of sunglasses may in some circum- stances unwittingly be either initiating or promoting melanoma. In a peculiar sense, our thesis is a logical extension of our view that the increasing exposure to artificial light is disruptive of some of the ‘natural immune mechanisms’ within the body which would otherwise protect us against melanoma. In support of this interpre- tation is consistent evidence which reveals a higher incidence of melanoma among indoor workers than outdoor workers.* A char- acteristic of indoor environments is that the eye receives only arti- ficial light. By modifying the sunlight entering our eyes, the wear- ing of sunglasses similarly results in the conversion of a natural light source into an artificial one. The result is that the eye is also receiving artificial light when one is out of doors. The possible connection between artificial light and skin cancer is subtle and we make no pretense that it is yet fully elucidated. A substantial body of literature is accumulating, however, which suggests that the link may be far more important than first assumed. It has been known for some time that light entering the eyes affects the function of the pineal gland and the production of pineal melatonin.‘ This gland and its hormones have been associated with several types of cancer,* and removal of the pineal gland has been shown to enhance carcinogenesis.* Melatonin is also associated with the activation of T lymphocytes, and melatonin can either stimulate or inhibit cell proliferation, apparently depending on the amount present. It is also clear that the photoperiodic environment of exposure may possibly be quite a significant factor in the regu- lation of melatonin.’ Early research showed that light in the visible region was responsible for pineal stimulation in rats‘. Recent research with other mammals, however, suggests that UV wavelengths as short as 30.5nm (UVB) also affect pineal function.’ SUNGLASSES AND SPECTACLES by Dr. Ronald S. Laura Professor in Education, University of Newcastle, P.E.R.C. Fellow in Health Education, and John F. Ashton ince the 1960s the incidence of melanoma has risen at an alarming rate,' despite the educational programs and considerable efforts intended to control it. According to the conventional wisdom on the subject, sunlight is the cause of melanoma and thus the way to avoid NEXUS - 17 THEY NOT ONLY AFFECT YOUR EYES, THEY AFFECT YOUR WHOLE BODY. SOME RESEARCH NOW LINKS SUNGLASSES WITH SKIN CANCER. Harvard.University Dept of Education, University of Newcastle. OCTOBER/NOVEMBER 1991 * YEAR BOOK