The concentration of lead in the atmosphere was measured at 13 locations throughout the city of Riyadh during the working week (Saturday and Wednesday). The concentration of lead was also measured in samples of soil taken from the same locations. The results indicate that lead concentrations in the atmosphere and soil were significantly higher in areas where the traffic density was consistently high than in more residential areas. There was a significant relationship between the concentrations of airborne lead and the corresponding concentration of lead in the soil (P < 0.01).