The fuel-characteristics of a particular gasoline-blend, which will resist igniting too early—and cause engine knocking and reduce efficiency in reciprocating engines—are measured as the octane rating of the fuel blend; the gasoline blend with the most stable octane rating then is produced in several fuel-grades for different types of motor. Tetraethyl lead and other lead compounds are not used in modern automotive gasoline, except in aviation, off-road motor vehicles, and racing car motors.[2][3]
Gasoline can be released into the Earth's environment as an uncombusted liquid fuel, as a flammable liquid, or as a vapor by way of leakages occurring during its production, handling, transport and delivery.[4] Gasoline contains known carcinogens.[5][6][7] Gasoline is often used as a recreational inhalant and can be harmful or fatal when used in such a manner.[8] When burned, one liter (0.26 U.S. gal) of gasoline emits about 2.3 kilograms (5.1 lb) of CO2, a greenhouse gas, contributing to human-caused climate change.[9][10] Oil products, including gasoline, were responsible for about 32% of CO2 emissions worldwide in 2021.[11]
On average, U.S. petroleum refineries produce about 19 to 20 gallons of gasoline, 11 to 13 gallons of distillate fuel diesel fuel and 3 to 4 gallons of jet fuel from each 42 gallon (152 liters) barrel of crude oil. The product ratio depends upon the processing in an oil refinery and the crude oil assay[12] (see § Etymology).
^Gary, James H.; Handwerk, Glenn E. (2001). Petroleum refining: technology and economics (4. ed.). New York Basel: Dekker. p. 1. ISBN978-0-8247-0482-7.
^Mehlman, MA (1990). "Dangerous properties of petroleum-refining products: carcinogenicity of motor fuels (gasoline)". Teratogenesis, Carcinogenesis, and Mutagenesis. 10 (5): 399–408. doi:10.1002/tcm.1770100505. PMID1981951.
^Baumbach, JI; Sielemann, S; Xie, Z; Schmidt, H (15 March 2003). "Detection of the gasoline components methyl tert-butyl ether, benzene, toluene, and m-xylene using ion mobility spectrometers with a radioactive and UV ionization source". Analytical Chemistry. 75 (6): 1483–90. doi:10.1021/ac020342i. PMID12659213.
^"Gasoline Sniffing". HealthyChildren.org. Archived from the original on 11 March 2024. Retrieved 11 March 2024.
^Ritchie, Hannah; Roser, Max; Rosado, Pablo (11 May 2020). "CO₂ and Greenhouse Gas Emissions". Our World in Data. Global Change Data Lab. Archived from the original on 19 April 2023. Retrieved 19 April 2023.