Ethylene Glycol Monobutyl Ether

2-Butoxyethanol (EGMBE) is a glycol ether solvent used in glass cleaners, all-purpose cleaners, and degreasers as a coupling agent — it keeps oil-soluble and water-soluble ingredients in one phase and improves drying without streaks. It's the characteristic-smelling ingredient in many blue glass cleaners. The occupational health concern is real: sustained inhalation or skin absorption at workplace concentrations can cause hemolytic anemia in animal studies. OSHA PEL is 50 ppm TWA (skin notation). But at 1–5% in a consumer aerosol used briefly, the exposure dose is orders of magnitude below any threshold of concern. The "gloves for prolonged or repeated contact" language in SDS Section 8 is appropriate for professional detailers doing multiple applications daily, not for a homeowner cleaning windshields weekly. Readily biodegradable (>60% in 28 days in OECD 301B), low aquatic toxicity, no persistence or bioaccumulation.