What type of laser could cause skin cancer if not used properly?

Question

a) Red semiconductor laser

b) Blue semiconductor

c) Eximer laser

d) YAG laser

Answer 1

Only the excimer laser will cause skin cancer.  Though the other answer is correct in saying that skin damage can result in skin cancer, the type of damage cause by red, blue, or IR (YAG) light will be the same type of damage that is caused by a hot object like a flame.  This type of damage, especially if chronic, can increase the likelihood of cancer, but only minimally.  Excimer lasers, on the other hand, produce UV radiation that causes damage in different way, by directly breaking molecular bonds, like those that hold DNA together.  This can lead much more directly to skin cancer, as it is the same effect that UV radiation from the Sun causes.  So, though all of them could increase likelihood of skin cancer, c) is the only one that would do it in an appreciable way.

Answer 2

All of the above and none of the above. Cancer can be caused by repeated damage to the skin cells caused by the deposition of energy into the cell. The more important factors are the exposure rates, energy/cm2 deposition, recovery time and susceptibility.

The lower the frequency the less likely that it will cause cancer at a given exposure rate but it is a stochastic (non-threshold) effect.