Ultraviolet Radiation Exposure: Some Observations and Considerations, Focusing on Some Italian Experiences, on Cancer Risk, and Primary Prevention

Abstract

Solar ultraviolet radiation may cause acute and chronic health effects on the skin, eyes, and also on the immune system. Actinic keratosis, non-melanoma skin cancers, and malignant melanoma are the main long-term adverse skin effects. In the white population, the most common type of cancer worldwide is skin cancer, and the incidence of this cancer has increased during the last decades. The most important risk factor responsible for this trend seems to be Ultraviolet Radiation (UVR). IARC has classified UVR as being carcinogenic to humans. UV radiation exposure is ubiquitous; to study skin cancer risk, it is important to take into account the fact that UV exposure may occur both for occupational activities but also during vacation or recreational activities. Furthermore, exposure to artificial UVR such as those emitted by artificial devices, classified by IARC as carcinogenic to humans, is also to be considered. Due to the prominent role of UVR, primary prevention of skin cancer is very suitable, because when following specific rules this risk factor can be reduced. The incidence rate of skin cancer is higher in people with fair skin. Outdoor workers exposed to solar UVR are at risk of developing skin cancer, particularly non-melanoma skin cancers, and welders exposed to artificial UVR are at risk of developing ocular melanoma. A specific project on solar UVR risk in outdoor workers in Tuscany, Italy, has shown that outdoor workers had an unsatisfactory sun protection behaviour. The project demonstrates the complexity of studying UVR exposure and recommended the need for prevention programs. Risk increases with increasing ambient solar radiation and with unsafe behaviours in the sun or when using artificial UVR (e.g., sunbeds). Effective prevention strategies have to be adopted both for the outdoor workers and for the general population exposed to UVR. A standardized program of proven efficacy, such as that implemented in Australia, should also be implemented in other countries. All these strategies could contribute to the aim of decreasing the morbidity and mortality of cancers associated with this exposure. The aim of this paper is to provide an overview of UVR exposure risk, particularly occupational risk, and to give some elements to understand the complexity of the relation between UVR exposure and cancer risk, as well as to outline primary prevention measures, focusing also on Italian experiences that could be useful for providing additional elements of knowledge on this topic.