Dose and Dose-Rate Responses to UV-B Radiation: Implications for Reciprocity
Solar UV radiation interacts with many organisms and systems within the biosphere. The pathway leading from the entrance of photons into the system to the system’s ultimate response is different for various systems and responses. Nevertheless, there are clear-cut parallels between various types of UV responses. This analysis is focused on the effects of various response mechanisms on the quantitative relationship among dose, dose-rate and response, which is the relationship playing a crucial role in risk assessments. In considering these effects, the processes involved are classified into 2 x 2 main categories: deterministic versus stochastic, and reciprocal versus nonreciprocal. The important, but at times vague, distinction between deterministic and stochastic processes is developed in some detail. In connection with this, the often misused concept of a memory effect of an exposure is also considered.
The law of reciprocity (i.e., that the response depends only on the product of dose-rate and exposure time) is important in photobiology. It is what one would expect on the basis of a photochemical reaction. Reciprocity is often found to hold true, to a good approximation, in photobiological experiments. Many responses fail, however, to obey this “law”; this applies especially to long-term responses. Various nonreciprocal processes are treated together with their effects. In connection with reciprocity, the importance of an appropriate definition of “dose” is emphasized.
KeywordsOzone Photosynthesis Toxicology
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- Anderson RR, Parrish JA (1980) A survey of acute effects of UV lasers on human and animal skin. In: Pratesi R, Sacchi CA (eds) Lasers in photomedicine and photobiology. Springer, Berlin Heidelberg New York, p 109Google Scholar
- Claesson S, Juhlin L, Wettermark G (1958) The reciprocity law of UV-irradiation effects. Acta Dermato-Venereol 38:123–136Google Scholar
- De Gruijl FR (1982) PhD Thesis. Chapter 1, State University UtrechtGoogle Scholar
- NBS (1976) National Bureau of Standards Tech Note 910–1:58Google Scholar