Preliminary assessment of the risks associated with solar ultraviolet-A exposure.
An approach is proposed to assess the periods of human skin exposure to solar ultraviolet-A (UV-A, 315-400 nm) irradiance in natural conditions that are able to yield doses found to trigger carcinogenesis in laboratory experiments. Weighting functions, adopted to perform such estimate are constructed, allowing for a comparison between environmental and laboratory doses. Furthermore, the impact of stratum corneum (SC) thickness on the studied environmental doses was investigated. Based on laboratory studies, it was found that exposure periods of less than a month, at mid-latitudes, could provide irradiance doses capable of causing tumor formation. The duration of these exposure periods closely depends on the exposure regime, atmospheric conditions and SC thickness. It is believed that the presented evaluations could provide a useful preliminary estimation of the risk associated with environmental UV-A exposure prior to the formulation of the corresponding action spectra and determination of the threshold doses.
Petkov
Boyan
B
Institute of Atmospheric Sciences and Climate (ISAC) of the Italian National Research Council (CNR), Via Gobetti 101, 40129, Bologna, Italy. b.petkov@isac.cnr.it
Vitale
Vito
V
Tomasi
Claudio
C
Gadaleta
Emanuela
E
Mazzola
Mauro
M
Lanconelli
Christian
C
Lupi
Angelo
A
Busetto
Maurizio
M
Benedetti
Elena
E
D045744:Cell Line, Tumor; D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D007753:Laboratories; D009381:Neoplasms, Radiation-Induced; D011829:Radiation Dosage; D018570:Risk Assessment; D012867:Skin / Q000528:radiation effects; D013997:Time Factors; D014466:Ultraviolet Rays / Q000009:adverse effects*