Mature stoner: why are so many seniors smoking weed? (theguardian.com)

Smoking / burning ANYTHING fills you up with toxins like benzene and benzaldehyde, vaping THC probably safer. Nose spray is least toxic. Seniors who smoke weed at all time high for Schizophrenia

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2424288/