European Chemicals Agency Seeks Comments on OELs for Toluene
A scientific report (PDF) published this month by the European Chemicals Agency includes ECHA’s recommendations regarding occupational exposure limits for toluene. The agency was tasked by the European Commission to evaluate toluene as part of the process for establishing OELs for the chemical agent in the European Union. One of ECHA’s scientific committees, the Committee for Risk Assessment (RAC), will use the agency’s new report to develop its opinion on OELs for toluene.
According to ECHA, toluene’s main uses include as an additive to enhance gasoline’s octane rating and as a solvent in industrial applications. The agency notes that toluene is used in many other applications, such as in paints, coatings, and textiles; as a laboratory reagent; and in products for de-icing, washing and cleaning, and leather treatment. Occupational exposure to toluene can occur in the petroleum and painting industries as well as in coke plants, and workers who manufacture products including coatings, adhesives, sealants, and polymers may also be exposed, ECHA’s report explains. Additional workers the agency says may be exposed to toluene include employees of gas stations, nail and hair salons, and car mechanics. The primary route of exposure for workers is via inhalation, but ECHA states that dermal absorption of liquid toluene can occur during tasks such as using glue by hand.
ECHA recommends an eight-hour time-weighted average (TWA) OEL for toluene of 77 mg/m3, or 20 ppm, and a 15-minute short-term exposure limit of 383 mg/m3, or 100 ppm. The agency also proposes a biological limit value (BLV) of 30 μg toluene/L urine as measured at the end of the work shift. According to ECHA, the BLV corresponds to its recommended eight-hour TWA value. The report also outlines proposed skin and noise notations due to toluene’s ability “to be rapidly and significantly absorbed through the skin” and because exposure to it may lead to “solvent-induced hearing impairment.”
“Toluene is known to cause direct cochleotoxic effects (involvement of both the inner ear and the central nervous system), enhanced if noise is present,” ECHA’s report states. “However, it should be noted that there is no clear data on dose-response relationships nor clear effects on auditory thresholds in humans.”
ECHA invites stakeholders to comment on its OEL proposals both to gather input on the report and to support RAC in adopting its opinion on OELs for toluene. Comments are due by Oct. 3. More information is available on the ECHA website.
Related: An educational session presented at AIHA Connect 2025 focused on considerations for controlling ototoxicant exposures. The Synergist has previously published articles that provide an introduction to ototoxicants and discuss challenges related to ototoxicants and hearing impairment for occupational hygiene.