Airborne lead concentration levels on the Korean peninsula between 1991 and 2004

In this study, a comprehensive analysis was made to describe the environmental behavior and pollution status of lead (Pb) in 13 major cities in Korea in a 14-year time span (1991–2004). The results clearly indicate that spatial distribution of Pb is clearly distinguished between different city types and between different temporal intervals. The Pb concentration levels in the cities of strong industrial activities are found to be higher than those of relatively clean ones by approximately an order of magnitude. Examination of the seasonal patterns indicated a strong consistency in almost all cities so that Pb concentration peaked during spring and winter, while it dropped noticeably during summer. If the long-term trend of Pb pollution is examined for the entire study period (14 years), it appears to contrast between different city types in relation with the relative intensity of Pb pollution. In cities of strong industrial activities, the reduction of Pb seemed to occur more effectively due to the stringent measures implemented to ban metal emissions over the past decades. In contrast, such temporal patterns appear to be more complicated in cities with moderately or fairly clean environments. This is possibly due to the fact that the effect induced by the phase-out of the dominant source (i.e., leaded gasoline) became less significant, while other sources were further diversified and/or intensified through time. The overall results of this comprehensive study confirm the fact that the status of Pb pollution in most city areas can be reflected fairly sensitively by changes in social and environmental conditions.