It's hard to say anything simply because one person was using it daily six times with adverse effects. There are many factors, such as solvent traces, temperature, DMT purity, etc.

Personally my body feels if something is bad for me, for example if I compare between nice and smooth DMT vapor and cannabis or tobacco smoke.

But I am quite sure it's bad for you if you vaporize it at too high temperature(which is easy to do with many vaporization methods), it's easy to tell from the taste and harshness.

My lungs love it when it's properly vaped:twisted:

If it would be as bad as tobacco smoke(which I highly doubt), it would be well worth it, especially when it's not used so often.

I'm not worried in the least bit.