You've got to be kidding. :/ As lwien said, you can't feel lead exposure. It just builds up in the body. I'm not saying the zap produces lead exposure. I don't know that cheap 'made in China box vapes' are unsafe either, but I'm not taking any chances there either. As for chromium, it's used by the body for processing blood sugar and is found in meat, potatoes, cheese, breads, fruits and vegetables. In large amounts it's toxic but so are lots of things, including water. As for absorbing toxic amounts of it from a stainless steel heat exchanger, the melting point of chromium is over 1900 degrees C, while lead melts at 327 C, so how are you safe from lead while I'm exposed to dangerous levels of chromium? I'd start being very careful about what you're presenting on this forum as facts. And if you can't post the exact quote from someone else's post, and provide the link, then I strongly suggest that you refrain from reporting what others have said. Lately some of your posts have been irresponsible and not up to the standards we require on this forum.