Possible risks in using LED light to monitor your heart rate Post No 2

I had written a post in this blog about possible skin-cancer risk posed by LED radiation used by activity trackers to monitor heart rate. Visit http://newstudentresearch.blogspot.in/2015/12/possible-risks-in-using-led-light-to.html  Today, my wife and I took a photograph of the tanned spot the tracker has created on my wrist. I notice that there is damage to the skin - it is not mere tanning. See the photograph below.