Polyoxyethylene Dinonylphenyl Phosphate

Polyoxyethylene dinonylphenyl phosphate is a phosphate ester nonionic surfactant used as a corrosion inhibitor and penetration aid in metalworking fluids and penetrating oils. It belongs to the nonylphenol ethoxylate (NPEO) derivative family. In penetrating oil formulations it helps displace water from metal surfaces and provides a corrosion-inhibiting layer. The H314 (skin corrosion) and H318 (serious eye damage) classifications apply to the pure substance — at 0.1–1% in the finished product, the mixture-level classification for skin/eye effects is driven by the overall product GHS classification, not this ingredient alone. The nonylphenol scaffold raises environmental concerns related to endocrine disruption potential, consistent with the NPEO family designation as substances of very high concern (SVHC) in some regulatory frameworks. At trace concentrations in aerosol penetrant formulations, direct aquatic exposure during use is primarily through indirect pathways (drainage).