C23: Very nice paper about human UV exposures through glass.

From: D.E. Godar DEG@CDRH.FDA.GOV
Date: 12/3/97
Time: 3:36:28 PM
Remote Name: 150.148.47.70

Comments

I found this paper to be very interesting from a number of diiferent perspectives including increased risk for skin cancer from ambient UV that penetrates through glass, mostly UVA. The authors found that the number of MEDs a person would receive in Australia could be doubled if they spend some time driving and/or working in a greenhouse (and possibly close to windows). These exposures can be of the same order of magnitude as those received during leisure activities. Of course, a truck driver would receive much more than the ordinary driver and the same applies to greenhouse workers. I am wondering if past cancer risk assessments took these exposures into account, but it doesn't seem likely since this is new information. We will definately have to take these findings into consideration in future risk assessments of skin cancer. Congradualtions on a very nice piece of work, and I must say it is well written also. I have a couple of quick questions. You say that the MEDs received from driving (I assume it is over the course of one year?) is about the same order of magnitude as that received during outdoor leisure activities, but the MEDs you are referring to are actually mostly from UVA. Isn't that correct? It wasn't clear in the abstract that stated UV, and not UVA. Or did I miss the small contribution from UVB. Also, if I read the paper correctly, a person in Australlia could be at as high as twice the risk for skin cancer as might have been calculated in the past. And of course, since this increased exposure is mostly in the UVA region, they would be at an elevated risk for primarily melanoma - according to Setlow's findings compared to deGruijl and van der Leun's findings for SCC in the UVA region. Could you comment on the implications your findings would have on cancer risk assessments and if anyone plans to redo these based on this new data. Also, now I am very curious as to what yearly exposure an American and a Northern European might receive in one year compared to an Australian. Can you make latitude adjustments and estimate what these differences might be? I really would like to know this because I hope to perform some risk estimates in the near future and total solar ambient exposure data is needed. Curiously, the Robertson-Berger meter yields a relative response curve that looks exactly like the SCUPh SCC action spectrum. I admit my ignorance in this area, but would this mean that it is the best meter for measuring UV, since it appears to be similar in it's sensitivity to UV as human skin?