Historical QOD 12/01/08: What compounds are used instead of ethylene glycol in ?non-toxic? anti-freeze? Are they potentially harmful?
Antifreeze traditionally contains ethylene glycol, but some brands marketed as low toxicity or ?non-toxic? use 1,2-propanediol (aka propylene glycol) or 1,3-propanediol (aka trimethylene glycol or 1,3-dihydroxypropane). Although less toxic than ethylene glycol, both compounds have been implicated as a cause of death with blood levels in the 400 mg/dL range.
Garg U, Frazee CC 3rd, Kiscoan M, Scott D, Peterson B, Cathcart D. A fatality involving 1,3-propanediol and its implications in measurement of other glycols. J Anal Toxicol. 2008 May;32(4):324-6. doi: 10.1093/jat/32.4.324. PMID: 18430302.