Continuous measurement of gaseous pollutants in Buenos Aires city

Data on CO, NO, NO2 and O-3 concentrations measured in Buenos Aires city us ing a continuous monitoring station are reported. This is the first systema tic study of this kind carried out in the city, which is, together with its surroundings, the third more populated in Latin America. Measurements were performed during 12 months in one of the principal avenues near downtown. Results indicate that vehicular traffic is the principal source of CO and N Ox. The concentration of O-3 is generally quite low and results from the mi xing of clean air masses with exhaust gases containing high amounts of NO. The monthly averages of CO and NO decrease from Winter to Summer in correla tion with the increase of the mean wind speed and average temperature. Thes e results are compared with previous measurements on the spatial distributi on of NO2 in the whole city using passive diffusion tubes and with the conc entration of CO, which is being continuously registered since several years in the downtown area. Measurements performed at a green, windy, low traffi c area beneath the La Plata river are also shown. (C) 1999 Elsevier Science Ltd. All rights reserved.