Reviewing the methodologies used to assess household PM2.5 air pollution in sub-Saharan Africa

Abstract

Exposure to household air pollution (HAP) is a major global health issue in low- and middle-income countries, with exposure to fine particulate matter (PM2.5) a major risk factor for a wide range of diseases. Sub-Saharan Africa (SSA) has unique contextual challenges for assessing HAP exposure, it is critical that learning from existing research is applied in future research. Reviews conducted to date have not considered in detail the methods applied when deploying PM2.5 sensors to measure indoor air quality, nor did they focus on HAP. A review of HAP PM2.5 measurement studies in SSA was conducted, focusing on measurement methods in order to understand how monitors have been deployed in the region. A search and extraction following PRISMA guidelines was applied. After exclusions, 51 papers were reviewed and information related to HAP sampling methods was extracted. Common themes in methodologies, assessing their effectiveness, and gaps in future research were highlighted. The findings highlight a considerable lack of research into HAP in the region where there is both an increasing population and an increase in the use of unclean fuels. A lack of standardisation in measurement practices was also identified. A key finding is the necessity for calibration of low-cost sensors against reference instruments within the region where they are deployed and calibrated against specific emission sources. This review provides recommendations to improving the accuracy and reliability of HAP measurement in SSA as well as key learnings for future larger-scale exposure and epidemiological studies to inform robust public health policy.