Indoor and outdoor PM2.5 and CO in high- and low-density Guatemalan villages

Continuous particles less than 2.5 mum in diameter (PM2.5) and carbon monox ide (CO) were monitored during breakfast, lunch, and dinner in three high-d ensity and four low-density villages near Quetzaltenango, Guatemala a to he lp assess the viability of this region for a proposed respiratory health an d stove intervention study. Approximately 15 homes were visited during each mealtime in each of the seven villages; in all, 98 homes were visited, wit h a sampling duration of 2-3 min per home per meal. For each village, a lin e (transect) was drawn on a village map along existing roads from one end o f the village to the other; homes and between-home outside locations along the transect were monitored. Although the predominant stove type was the op en fire, several other stoves, in various levels of disrepair, were observe d frequently. The highest indoor concentrations of PM2.5 were observed in h omes using the open fire (avg.= 5.31 mg/m(3): SD = 4.75 mg/m(3)) or equival ent, although homes using the plancha - indigenous wood-burning stove with chimney - also had measurements >13.8 mg/m(3), PM2.5 limit of detection. Th e highest indoor concentrations of CO were also observed in homes using the open fire (avg.=22.9 ppm; SD=28.1 ppm),with a maximum measurement of >250 ppm. For both PM2.5 and CO, levels measured in homes with plancha, lorena, or open fire were significantly higher than levels taken in the street or i n homes using a gas stove. The Spearman correlation coefficient between PM2 .5 and CO for all data combined was 0.81, and ranged from 0.30 for the lore na to 0.68 for the plancha in homes using wood-fueled stoves. Although indo or PM2.5 and CO levels were not significantly different between high- and l ow-density villages, street-level PM2.5, (p = 0.002) and CO (p = 0.002), we re significantly higher in the high-density villages. These data provide a useful picture of the pollution levels coming from a range of cooking stove s in various levels of disrepair, as well as a representation of how outdoo r particle moss and CO levels vary from high- versus low -density villages.