The pun is so satisfying that I'm compelled to point it out. https://dictionary.cambridge.org/dictionary/english/integral
Graph(my coloring) and chart from
https://pmc.ncbi.nlm.nih.gov/articles/PMC9117256/
I will critique an excerpt from an article written by a member of the Norwegian expert commission. My argument is that the mentioned amounts of THC are not sufficient to produce psycho-motor effects.
Article link: https://tidsskriftet.no/2017/10/kronikk/effekter-av-cannabis-varer-lenger-enn-antatt
Translated excerpt:
"As THC is redistributed, significant amounts of THC can be present in the blood over time. THC concentrations sufficient to produce psycho-motor effects and impaired cognition have been measured for approximately 10–15 days and have been detectable for up to 30 days."
Relevant to the pun intended: In mathematics, an integral is a calculation of the area below a graph. In the graph to the left, the green area under the graph is the amount (ng) of THC per 1 ml of whole blood over a period of time.
You can think of the disappeared parts of the green area every interval as the amount of THC that is absorbed into the brain and fatty tissues in the time after smoking cannabis.
Impairment at 20 minutes should be understood as a carry-over effect produced by the absorption of the peak observed in the first few minutes. It is possible to test this claim by administering an amount of THC that will produce an initial peak at 20 ng/ml.
At 180 minutes the same is true, but then we have to take into account that significant amounts of the absorbed THC has been metabolized.
Another way to describe this is to take the average and maximum percentage of impairment and compare it to the THC levels in blood. If we ballpark APMI/(ng/ml) at certain points for both average and maximum levels of ng/ml and impairment we get a wide discrepancy in a number that should be quite similar to point to a stable correlation between ng/ml of THC and degree of impairment.
0 min avg: 90 APMI/65 ng/ml = 1,39
0 min max: 115 APMI/115 ng/ml = 1
20 min avg: 85 APMI/20ng/ml =4,25
20 min max: 105 APMI/45 ng/ml = 2,34
60 min avg: 45 APMI/15 ng/ml = 3
60 min max: 75 APMI/25 ng/ml= 3
120 min avg: 15 APMI/15 ng/ml = 1
120 min max: 35 APMI = 15 ng/ml = 2,34
180 min avg: 5 APMI/ 5 ng/ml = 1
180 min max: 20 APMI/ 10 ng/ml = 2
The takeaway is that a blood level of 5 ng/ml does not provide impairment in and of itself. Absorption 3 hours back is a prerequisite for the impairment seen at 5 ng/ml.