Vapes typically use lower temperatures than smoking. A Google search should show a plethora of discussion over the safety of brass for smoking devices. The general consensus is brass is one of the safest metals to smoke through. It should not be Chrome or nickel plated however and should be lead free. By definition brass is an alloy of copper and zinc. Other metals are sometimes also included in the mix for various reasons cost machinability Etc brass pipes are still manufactured and sold worldwide