While I went hiking with my dad, I took the lead, so I didn't see him for a minute. Then I smelled something, taking a deep breath. I looked back, and there he was, about 3 feet away with some tinfoil in his hand.
I figured it was an illegal drug, so I immediately exhaled and got far away from him. I tried breathing in clean air over and over, in order to make sure the drug had no effect on me, but again, some tiny amounts were in the air, even far away.
Could the amount that I breathed have caused me to experience ANY effects of this drug? I felt a little bit light-headed but I'm not sure if that was due to my intense fear of having inhaled it on accident. Mentally, I never want to be exposed to a drug even once. My question is basically, then, what is the minimum ppm that crack cocaine requires to induce the bare minimum amount of psychological effect, and what would the ppm be at 3 ft from a smoker outdoors (with the wind blowing toward me in the worst case)?
Thanks.