if you believe the University of Arkansas (which is a pretty credible source to me), then, no, the process of eliminating harmful substances from your body is done through the kidney, liver and intestines, just as you suggest. Here is a link http://uamshealth.com/healthlibrary2/medicalmyths/canyousweattoxinsoutof….
The word “toxin” has been so overused lately. A toxin is a substance that can cause disease when present in the body, and encompasses many natural and synthetic sources. Our body removes toxins through the liver, kidneys and intestines quite effectively, but the skin is not a mode of toxin removal.
Our skin provides a barrier from the environment and our body, and functions to regulate internal temperature through sweating, conduction and convection and radiation. When we sweat the fluid produced consists of predominately water, some trace minerals, lactic acid and urea.
Sweating does not draw toxins out of the body, and unless there were toxins present on the surface of the skin that sweat would remove, the process of sweating exclusively provides a way for the body to cool internal core temperature through evaporation heat loss.