I don't know for sure, but I can tell you that I had a severe and constant allergic reaction when exposed to it that would involve losing my voice, abscesses in my throat, a severe blistered rash that covered my whole back, when enduring heavy exposure to the hands it would cause them to peel, and they'd burn when exposed to direct sunlight in the summer. All of my dark skinned colleagues hair would bleach out platinum blonde on their arms, and it would kill grass faster than any weedkiller I've ever used. It took me 6+ months of requesting and multiple Dr. visits to finally obtain a copy of the MSDS that to this day I swear was fake. So from my point of view, YES HELL IT IS VERY TOXIC!!!
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