Brazil's discontinued 'blue gasoline' high‑octane fuel history

Blue gasoline, known locally as "gasolina azul," was a high‑octane 95 RON fuel distinguished by a blue dye and the presence of tetraethyl lead. It was essential for high‑performance vehicles such as the Dodge Charger R/T, which required its high octane and anti‑knock properties.

The fuel existed alongside a lower‑octane "yellow" gasoline (87 RON). The 1970s oil crisis prompted Brazil's Proálcool program (established in 1975) to promote ethanol. The first ethanol‑only car, the Fiat 147, appeared in 1979. In 1982 the government added 12 % ethanol to regular gasoline, raising its octane to match the former blue gasoline and ending the distinction between the two fuels.

Today Brazil sells gasoline with an average octane of 91 RON (regular) and premium grades up to 98‑103 RON, containing around 32 % ethanol, a shift from the lead‑based formulation that disappeared with the end of blue gasoline.