What it is
Pungent pressed mustard-seed oil, a traditional cooking fat across North India and Bengal — and sold in the US labeled "for external use only."
Why your biology objects
Here the flag isn't linoleic acid (a modest ~15%) — it's erucic acid at 20–40%, a very-long-chain fat the heart oxidises poorly and that caused myocardial lipidosis in animal studies. Food limits cap erucic acid at 2%; traditional mustard oil runs 10–20× that. Genuinely ancestral in origin, but the specific molecule is the problem.