In Reply.—
I am pleased that Young agrees that it is not possible to obtain a safe tan by whatever means. At least we agree on one point because, unfortunately, there is little else in his letter I can agree with.I did not say "that nobody has studied the possible protective benefits of a tan induced by a bergapten-containing sunscreen." I did say that the question "has not been adequately studied by anyone."1 I was well aware of the two studies he cites and worded my comment in that way because of the inadequacies of both studies. Young et al2 claim, and presumably believe, they measured the amount of DNA damage induced by exposure to solar-simulated (SS) radiation to compare the protection afforded by a bergapten-induced tan vs a tan induced by SS radiation alone. They are wrong. They measured repair of DNA damage by testing for unscheduled DNA