Gasoline's Lead Reduction in Mexico City -It's Effects in the Air Quality

With a population of near than 18 million people, the Mexico City Metropolitan Zone (MCMZ) in the Mexican Basin has the most serious ozone problem in Mexico. Sunshine, altitude (2240m), light winds, poor ventilation and mountains forming a closed basin, concentrate the pollutants wich facilitate ozone formation. 0-zone concentrations in the Mexican Basin have been increased since fall 1986. The increase of the ozone events has coincided with the introduction by Petroleos Mexicanos of a new gasoline with a tetraethyl lead concentration of 0.64 ml/gal and a aditive detergent with amine base.