Nothing, Ian Kidd does better writeups on drugs testing in combat sports than anyone and already debunked the hair test nonsense, that poster is just parroting talking points he's heard from clowns like Montoya and Montero.
Debunking the misinformation around Canelo’s clenbuterol positives
The hair test
There has been a push in some quarters to use the “hair test” in order to convict or clear Canelo. To hear it told, this hair test is the answer to every question. In reality, hair testing for clenbuterol isn’t used for a reason; it’s incredibly unreliable.
The amount of clenbuterol that shows up in hair varies
massively depending on factors like hair color.
One study gave a group of people the same amount of clenbuterol. One participant, a 27-year-old female, showed 23 ng/g of clenbuterol in her hair afterwards. Another participant, also a 27-year-old female, showed 161 ng/g of clenbuterol in her hair. They both took the exact same amount, but one had seven times as much in her sample. The suggested reason for this discrepancy? The women had different hair color. This hair color discrepancy was supported by the other data in the study.
That might sound ridiculous, but other studies have found the same thing.
Another study, with more participants, found that even among subjects with similar hair color, the variation is still large. Despite every subject having hair listed as “brown” or “dark brown”, this study also found significant variation:
The lowest detected amount of clenbuterol in the first segment of hair was 0.43 pg/ng, the largest amount was 4.76 pg/ng. Both of these subjects had hair classed as “brown,” and both took the same amount of clenbuterol in the same way. That’s a difference of an entire order of magnitude. A similar issue was found in the second segments, which ranged from a detected amount of 0.00 pg/ng to 0.86 pg/ng.
Tests that have results varying by so much even under a controlled conditions are
not reliable tests. The idea that they would somehow give us the information we need to determine if Canelo accidentally or deliberately ingested clenbuterol is ridiculous.