Comment · Wed, February 3, 2021 · ND Owner
NAC smells like sulfur?
Original post in this thread
SnooGuavas2619 · 0 points
I recently got some NAC capsules, and the bottle smells very strongly of sulfur. I know it's not uncommon, but I've been reading about it and many people are saying that NAC is sensitive to heat and that the strong smell could mean that it's oxidized. Is this true? I know temperatures in Arizona are very high, and I also live in a hot country, so maybe it oxidized during shipping?
What they were answering
novacog · 1 points
While researching I came across this older post by you which contradicts your current post. It was on a post that was worried the ND NAC didn't have a sulfur smell. Guessing your data and understanding have changed since a couple years ago or am I misinterpreting? Thanks!
"The stronger the sulfur smell, the more oxidized the NAC has become. That smell is H2S, or hydrogen sulphide. That is created when it's exposed to oxygen, and the SH grouping on the end of the NAC molecule gets ripped off due to oxidation. We specifically handle our NAC in such a way to expose it to as little oxygen as we can, and store it with oxygen absorbing packs in double-sealed containers away from light and heat. We also use PETE jars, which are very good at protecting from oxygen permeation in comparison to other plastics like HDPE or PP. If you were to buy pharma brand Fluimucil, it woudl come in blister packs and have no smell as well."
u/MisterYouAreSoDumb · ND Owner
Yeah, that's what I thought was the case at the time. It's what I was being told by some scientists. However, we later decided to run our own testing in the lab to prove it. It turns out it does not oxidize under normal conditions as a powder. We think the smell is H2S gas trapped in the crystal structure of the NAC, not it actually oxidizing. This would explain why it goes away if you leave it out for a while. The H2S gas releases from the crystal structure it is trapped in, and you can smell it. It's not NEW H2S gas forming from the oxidation of the NAC sitting there. So the sulfur smell is H2S, but it is not forming right then and there because of oxidation. It was already trapped in the crystal structure of the NAC at the time of crystallization during the synthesis.