I've used it, as a supplement to my testosterone injections. I believe a few pharmacies still have some stores of DHT but it's not easy to find. I don't know how accessible it is in Canada these days.
Yes, it is possible to accidentally get those hormones on someone else if you're using a topical cream (T or DHT). It's not that you sweat it out, but rather, if people come in contact with the areas you apply it. Or, if you are not careful after application and still have residue on your hands. I don't about that show, but from what I've read, DHT cream has been used for boys with micropenis just before they naturally enter puberty, to give them a chance for extra growth there.