A pilot study to assess ground-level ambient air concentrations of fine particles and carbon monoxide in urban Guatemala

摘要

Ambient concentrations and the elemental composition of particles less than 2.5 μm in diameter (PM_(2.5)), as well as carbon monoxide (CO) concentrations, were measured at ground-level in three Guatemalan cities in summer 1997: Guatemala City, Quetzaltenango, and Antigua. This pilot study also included quantitative and qualitative characterizations of microenvironment conditions, e.g., local meteorology, reported elsewhere. The nondestructive X-ray fluorescence elemental analysis (XRF) of Teflon filters was conducted. The highest integrated average PM_(2.5) concentrations in an area (zona) of Guatemala City and Quetzaltenango were 150 μg m~(-3) (zona 12) and 120 μg m~(-3) (zona 2), respectively. The reported integrated average PM_(2.5) concentration for Antigua was 5 μg m~(-3). The highest observed half-hour and monitoring period average CO concentrations in Guatemala City were 10.9ppm (zona 8) and 7.2ppm (zonas 8 and 10), respectively. The average monitoring period CO concentration in Antigua was 2.6 ppm. Lead and bromine concentrations were negligible, indicative of the transition to unleaded fuel use in cars and motorcycles. The XRF results suggested sources of air pollution in Guatemala, where relative rankings varied by city and by zonas within each city, were fossil fuel combustion emitting hydrocarbons, combustion of sulfurous conventional fuels, soil/roadway dust, farm/agricultural dust, and vehicles (evaporation of gas, parts' wear).