[ulrikrasmussen]

The author points out a synthesis route that includes lead in a reducing agent, and I think that other routes also depend on reducing agents that contain mercury (aluminum amalgam). Heavy metal exposure is cumulative, so even small amounts over a long time could be significant. They also disrupt the same dopaminergic system that heavy doses of stimulants disrupt, so the effects could be hard to find if we only look at the population that uses illicit stimulants.

Heavy disclaimer: I am neither a chemist nor a doctor, so this is speculation on my part.

[zephen]

Yes, if there are multiplicative effects from the different disruptors, that could certainly have a large effect.

[ulrikrasmussen]

Indeed, and for a layman like me it even sounds quite plausible that this could be what is making people go "mad as a hatter": https://en.wikipedia.org/wiki/Erethism

Add to that that the routes of administration preferred by heaver users (smoking and injection) are also those that maximize the harms of mercury exposure.

[zephen]

Some tested samples had mercury. Others, formic acid. Neither one great to inhale.

https://www.dea.gov/sites/default/files/2025-09/CY%202023%20...

[ulrikrasmussen]

Thanks! Only about 2-3% of their samples seemed to contain mercury though, so it is not as prevalent as I could fear. As far as I understand the report, the vast majority of P2P syntheses use a Leuckart reaction and so do not depend on a heavy metal containing reducing agent.