What about safe amount of chlorine to drink? Piss?
Chlorine is toxic, and you should not drink it, but tap water has a small amount to ensure to kill al bacterias. We had a cholera epidemic like 30 years ago, and the official recommendation was to add two drops of chlorine to water if you were unsure if it was clean enough. Also swimming pools have chlorine, more than tap water, but you are not suppose to drink too much of it.
A few years ago a moron pissed in a water reservoir and uploaded the video to youtube, so it was an unnecessary public outrage and the water authorities decided to release all the water and fill the reservoir again, as if birds and squirrels use the toilette. Don't ask about swimming pools.
Gasoline? Sometime food has contamination form industrial oil, gasoline and other stuff. It was common to use benzene to remove the natural oil from flour, but I think they changed to another safer solvent. Anyway, there are safety limits for all of that. Zero is very difficult because chromatography is too sensitive.
Cigarette smoking? Probably zero cigarettes is the best, but I remember a silly trend a few years ago about third hand smoke, i.e. how dangerous was to go to a home a few years after someone smoked there and you can still get a small amount of toxic compounds released by the walls contaminated with the smoke.
Asbesto? A single fiber can kill you, but two fibers have like the double of probability to kill you, and a million fibers are even more dangerous. In which case should a building be declared inhabitable?
Chlorine is toxic, and you should not drink it, but tap water has a small amount to ensure to kill al bacterias. We had a cholera epidemic like 30 years ago, and the official recommendation was to add two drops of chlorine to water if you were unsure if it was clean enough. Also swimming pools have chlorine, more than tap water, but you are not suppose to drink too much of it.
A few years ago a moron pissed in a water reservoir and uploaded the video to youtube, so it was an unnecessary public outrage and the water authorities decided to release all the water and fill the reservoir again, as if birds and squirrels use the toilette. Don't ask about swimming pools.
Gasoline? Sometime food has contamination form industrial oil, gasoline and other stuff. It was common to use benzene to remove the natural oil from flour, but I think they changed to another safer solvent. Anyway, there are safety limits for all of that. Zero is very difficult because chromatography is too sensitive.
Cigarette smoking? Probably zero cigarettes is the best, but I remember a silly trend a few years ago about third hand smoke, i.e. how dangerous was to go to a home a few years after someone smoked there and you can still get a small amount of toxic compounds released by the walls contaminated with the smoke.
Asbesto? A single fiber can kill you, but two fibers have like the double of probability to kill you, and a million fibers are even more dangerous. In which case should a building be declared inhabitable?