That post was in response to a person who was vaping 36mg/ml liquid, at a rate of about 2 millileters per day. Not 72mg/ml. Please, you're not understanding the toxicity or the physiological affects of nicotine. If you ingested 1 millileter of 75mg juice within an hour, your heart would probably stop. Or you'd maybe be just wishing it would. You would be very very ill. Any more questions? BETTER LOOK INTO IT > A BIT FURTHER.
If a person smokes 3 packs of cigarettes per day, you may ingest up to 70 mg of nicotine. The half-life of nicotine in your body is about one hour, depending on you metabolism. So your total intake may be 70, but at any one time you may have in a twelve hour period of time, about 6mg of nicotine ingested for that hour.
If you vape 36mg/ml liquid, a total of 3-4 ml of juice total for the day, say 12 hours, your nicotine ingestion for an hour would be about 12mg. That would test out to be about 1.2 mg nicotine, because with vaping our bodies only absorb about 10% of the total ingested, because unlike smoking, our lungs are not absorbing the nicotine, the absorbtion is taking place in our mouths, nose, and throat. That's the theory anyway. And the testing numbers you referred to is the level of cotinine in you blood, which is a by-product of nicotine absorbed and processed by your body. It is not the nicotine amount you ingested, it is simply the testing standard of measure, whether you test in saliva, urine, or plasma. So the numbers I used here are just the number of mg of nicotine ingested, it probably would not test out at those levels after absorbtion.
The nicotine concentrations you are talking about would require you to wear a haz-mat suit to re-fill your cartridge. Wanna vape it?