This is a very important question when you are about to purchase any silicone pipe or a bong. The first thing you have to remember is that all WEEDGETS pipes use borosilicate glass bowls or surgical high temperature steel for the burning of the flower. Silicone bodies of the pipes are just transferring much lower temperature smoke. There are a lot of studies that have been done on this, and the conclusion is always the same – silicone is one of the safest materials to use for cooking or smoking due to its very high melting point temperature. Please know that we only use Medical Grade silicone, which is one grade higher than the food grade silicone many people are using to cook with.