Patterns of domestic exposure to carbon monoxide and particulate matter in households using biomass fuel in Janakpur, Nepal

Abstract

Household Air Pollution (HAP) from biomass cooking fuels is a major cause of morbidity and mortality in low-income settings worldwide. In Nepal the use of open stoves with solid biomass fuels is the primary method of domestic cooking. To assess patterns of domestic air pollution we performed continuous measurement of carbon monoxide (CO) and particulate Matter (PM2.5) in 12 biomass fuel households in Janakpur, Nepal. We measured kitchen PM2.5 and CO concentrations at one-minute intervals for an approximately 48-h period using the TSI DustTrak II 8530/SidePak AM510 (TSI Inc, St. Paul MN, USA) or EL-USB-CO data logger (Lascar Electronics, Erie PA, USA) respectively. We also obtained information regarding fuel, stove and kitchen characteristics and cooking activity patterns. Household cooking was performed in two daily sessions (median total duration 4 h) with diurnal variability in pollutant concentrations reflecting morning and evening cooking sessions and peak concentrations associated with fire-lighting. We observed a strong linear relationship between PM2.5 measurements obtained by co-located photometric and gravimetric monitoring devices, providing local calibration factors of 4.9 (DustTrak) and 2.7 (SidePak). Overall 48-h average CO and PM2.5 concentrations were 5.4 (SD 4.3) ppm (12 households) and 417.6 (SD 686.4) μg/m3 (8 households), respectively, with higher average concentrations associated with cooking and heating activities. Overall average PM2.5 concentrations and peak 1-h CO concentrations exceeded WHO Indoor Air Quality Guidelines. Average hourly PM2.5 and CO concentrations were moderately correlated (r = 0.52), suggesting that CO has limited utility as a proxy measure for PM2.5 exposure assessment in this setting. Domestic indoor air quality levels associated with biomass fuel combustion in this region exceed WHO Indoor Air Quality standards and are in the hazardous range for human health.

Household Air Pollutionin Rural Western Kenya: A Major Public Health Challenge

“…This zone covers 848.64 km 2 and it constitutes 34% of the total area of the County (GoK, 2013a).The soils found in this zone are red and brown clays derived from volcanic ash. These soils are fertile with a high content of clay mineral which gives a continuous supply of plant nutrients (GoK, 2013a).…”

Performance of low-cost monitors to assess household air pollution

“…TZOA-R had a firmware bug in the internal Real Time Clock, resulting in poor time stamp mapping). However, this is not the case of the EL-USB-CO, which is an established device that has been previously used in household air pollution studies as a personal monitor 53,54 and as an indoor monitor 16,55,43,56,57 . Generally it has been used to measure CO for periods of 24h or less, although three studies have attempted to use it for longer periods 43,54,56 .…”

“…Although the EL-USB-CO has been widely used to assess CO levels in different settings 16,43,[53][54][55][56][57][58] , there are limited published reports evaluating the performance of the EL-USB-CO monitor versus benchmark monitors under semi-controlled or real-world conditions. However, we highlight the work in Ghana of Piedrahita et al 58 who identified failure and malfunction of the EL-USB-CO in 25% of their sampling days and subsequently conducted laboratory tests to further investigate its performance.…”

“…We used the DustTrak DRX (Model 8534, TSI Inc., MN, USA) and the Q-Trak (Model 7575, TSI Inc.) as the PM 2.5 and CO benchmark monitors, respectively. Although they are not regulatory-grade monitors, their portability and affordability have made them widely used in prior air quality research studies 4,25,27,28,[43][44][45][46] . We also included a PM 2.5 sampling pump (BGI4004, BGI/Mesa Labs Inc., Waltham, MA, USA) provided with a cyclone sampler (GK2.05SH (KTL), BGI/Mesa Labs Inc.) and 37-mm and 2-µm pore size Teflon filters (Zefon International Inc., Ocala, FL, USA).…”

Comparison of next‐generation portable pollution monitors to measure exposure to PM 2.5 from household air pollution in Puno, Peru

“…While the relationship between CO and PM 2.5 was well-validated for the specific setting of the Western Highlands in Guatemala, this relationship has been shown to have poor-to-moderate correlation in other contexts. 16,17 Traditional pump and cyclone approaches for assessing personal exposure include a battery-powered sampling pump typically worn on the hip or in a backpack with tubing attached to a particle size-selective device installed in the human breathing zone. 11,18 These setups are generally expensive, noisy, heavy, and bulky for personal exposure measurements on women and children 19,20 and are often filter-based, requiring laboratory analysis and delaying results for study participants and subsequent analyses.…”