IARC Monographs Volume 138 / Automotive gasoline and five oxygenated gasoline additives - July 2026

IARC Monographs Volume 138 / Automotive gasoline and five oxygenated gasoline additives MTB / ETBE / TBA / DIPE / TAME - July 2026

ID 26941 | 23.08.2026 / Download Volume 138

This volume of the IARC Monographs provides evaluations of the carcinogenicity of automotive gasoline and five oxygenated gasoline additives – methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-butyl alcohol (TBA), diisopropyl ether (DIPE), and tert-amyl methyl ether (TAME).

Automotive gasoline (referred to hereafter as “gasoline”) is a commercial product primarily used in internal combustion engines. A complex mixture with a composition that has changed over time, it typically comprises volatile, petroleum-derived hydrocarbons, including alkanes, alkenes, and aromatics, which are blended with various additives. The oxygenated additives MTBE, ETBE, TBA, TAME, and DIPE are volatile compounds that have been used in gasoline to increase combustion efficiency, especially since the elimination of lead. All are listed as high-production-volume chemicals. The most widely used, MTBE and ETBE, are no longer added to gasoline in the USA, but are currently used in Europe, Asia, and elsewhere.

Occupational exposure to gasoline is expected mainly during the production and transport of gasoline and during vehicle refuelling, and includes occupations such as service station attendants, refinery workers, tanker truck drivers, automobile mechanics, and gasoline pump repairers and inspectors. For the oxygenated additives, workers may be exposed during production and via gasoline vapour in any of the above occupations. The general population is mainly exposed via gasoline vapour occurring at service stations, in air pollution, or in water and soil contaminated by gasoline spills.

An IARC Monographs Working Group reviewed evidence from epidemiological studies in humans, cancer bioassays in experimental animals, and mechanistic studies to assess the carcinogenic hazard to humans of exposure to these agents and concluded that:

- Automotive gasoline is carcinogenic to humans (Group 1);
- MTBE and ETBE are possibly carcinogenic to humans (Group 2B);
- TBA, DIPE, and TAME are each not classifiable as to its carcinogenicity to humans (Group 3).

[...]

Fonte: IARC




Info / download

Collegati
List Agents classified by the IARC Monographs