Comment by jccooper

For context, leaded gasoline phase-out began in 1973, based on the 1970 Clean Air Act. It was largely gone in the US by the 80s but not officially eliminated (except for General Aviation) until 1996. Other countries continued to use leaded gasoline, largely in Africa and the Middle East; the UN started an effort in 2002 to eliminate it in those places still using it. In July 2021, the last stocks of leaded gasoline (in Algeria) were exhausted (probably literally).