Dipropylene glycol (SIDS)

OECD SIDS
DIPROPYLENE GLYCOLE
5. Conclusions and Recommendations
5.1 Conclusions
Commercial dipropylene glycol (CAS # 25265-71-8; (CH3-CHOH-CH2O-CH2-CHOH-
CH3) is composed of 3 isomers and is typically 98% pure. The commercial product is
typically composed of up to 48% isomer 110-98-5. Dipropylene glycol is produced as a
byproduct of the manufacture of propylene glycol. The US production capacity of
dipropylene glycol was 131 million pounds (60 thousand tonnes) in 1998. Dipropylene
glycol is used as both a reactive intermediate and as a solvent. Reactive intermediate end
uses in the US include: plasticizers, unsaturated polyester resins, polyurethane polyols,
and alkyd resins. Solvent end uses in the US include: cosmetics, pesticides and functional
fluids: specialty deicers, inks, lubricants.
Dipropylene glycol is a liquid at room temperature, it has a low vapor pressure, and is
miscible with water. Releases to the environment are expected to partition primarily to
water and soil where they will be degraded. It is not expected to bioaccumulate due to
BCFs measured at 0.3 to 4.6. Testing in aquatic species showed a low hazard concern.
PNECs of >50 mg/L were obtained from a fish LC 50 of 5000 mg/l and 32 mg/l from a
clawed toad (Xenopus laevis) LC 50 of 3181 mg/l. The mammalian acute toxicity of
dipropylene glycol is low, with values around 16000 mg/kg reported in tests in rats.
Dipropylene glycol is only minimally irritating to the skin and eye. It appears to have low
potential to produce allergic skin reactions, as only 1 of 503 patients with eczema reacted
to dipropylene glycol. Longer-term studies of dipropylene glycol and the structural
analogues, propylene glycol and tripropylene glcyol, demonstrate a low concern for
chronic, reproductive, and developmental effects. Dipropylene glycol is not genotoxic
and not expected to be carcinogenic.
5.2 Recommendations
The chemical is currently a low priority for further work.
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