Chapter 9: Solvents and hydrocarbons · Part 1: Glycol ethers
DPnB
- Made from a hazardous chemical
The worst fact: it damaged chromosomes in 3 of 5 tests on mammal cells in a lab dish, although a mouse test was negative.
Why brands use it: it's a stronger grease solvent than PnB and couples water and oil.
Take care if: nothing beyond normal label directions.
Comes from: propylene oxide reacted with butanol. Australia classes propylene oxide as "May cause genetic defects; May cause cancer". That doesn't mean it's in the product, but it's not a great starting point for something you clean with.
Myth check: "Low-odour means low-hazard": smell says nothing about safety, either way.
Contaminants: nil.
Fair to say: the OECD rated it low priority for further work, and it's only slightly irritating to eyes. The US EPA's Safer Choice list marks it with a yellow triangle: it meets the program's criteria and is among the safest for its job, but has some hazard profile issues.
Correct as of November 2026. What the badges mean
Sources
- Safe Work Australia. Hazardous Chemical Information System (HCIS): classifications for each chemical, and for ethylene oxide, propylene oxide, epichlorohydrin, benzene, 1,3-butadiene-containing butane and 1,2-dichloroethane. Workplace exposure standards (amended November 2025) and workplace exposure limits (July 2025). Labelling of workplace hazardous chemicals code of practice (2015). Trichloroethylene health monitoring guide.
- US EPA. Trichloroethylene; regulation under TSCA, 89 FR 102568 (2024), and later notices (2025–2026); Perchloroethylene; regulation under TSCA, 89 FR 103560 (2024), and 91 FR 47145 (2026); 40 CFR 751.305 and 751.605; Carbon tetrachloride rule (2024); IRIS: ethylene glycol monobutyl ether (2010); Safer Choice Ingredient List.
- OECD. SIDS initial assessment: propylene glycol ethers (SIAM 17, 2003).
The full source list is at the end of Chapter 9.