This has been discussed and addressed over the 58 pages of this thread.
The best advice you could be given is to read back through the entire thread.
There is a good chance you will find the information you are looking for.
The tubes at least have been approved by FDA (US FDA 21 CFR 177.1975) regulations, as have the mouthpieces, and water accessories.
As for the mold injected casing...
The casing of the NO2 meets the requirements and is approved by the United States FDA for use in food contact applications and it is heat resistant within the applicable temperature range. Further, the pure Brass heating element has been independently lab tested for performance and chemical content. The testing also included lead, which we felt was very important given the recent focus on lead being found in products without the owners knowledge. Vaporstore.com claims that their independent lab tests found the NO2 had a minuscule trace amount of 0.01%, this is less than what is often found in the air we breathe!
This lab's study is published, and registered with the FDA
Info available at
Vaporstore. Contact them for specifics, or research it on your own. (You have a direction now to follow to do your "homework")
These people are very cautious about publishing data, that might contradict FDA requirements/restrictions.