2500 micrograms in one ml.
The published occupational limit for AP, which I believe is for a normal "work day" is 135 micrograms, and even this limit is under some scrutiny with some believing it's actually too high.
So, in 1ml of that particular liquid, the vaper is exposed to over 18 times the current occupational limit.
At 3ml per day, the exposure is 7500, which is more than 50 times the occupational limits.
Bear in mind also that some vapers inhale to the deep lungs, rather than a worker might inhale lightly through the nose when subjected to these compounds in a factory/working environment. So there could be different levels of risk depending on whether or not a vaper mouth inhales, or lung inhales. I believe Dr Farsalinos is doing some investigation in this area, but may need more funding to proceed.