Personal Exposure to Fine Particles (PM2.5) in Northwest Africa: Case of the Urban City of Bamako in Mali

Personal exposure to particulate matter (PM) from anthropogenic activities is a major concern in African countries, including Mali. However, knowledge of particulates is scant. This study was undertaken to characterize personal exposure to PM2.5 microns or less in diameter (PM2.5) in the city of Bamako in Mali. The exposure to PM2.5, through daily activities was observed from September 2020 to February 2021. Participants wore palm-sized optical PM2.5 sensors on their chest during their daily activities. The exposure levels in four different groups of residents were investigated in relation to their daily activities. The variation in PM2.5 concentration was measured during different activities in different microenvironments, and the main sources of exposure were identified. The highest average 10 min concentrations were observed at home and in bedrooms, while the participants were using specific products typically used in Africa, Asia, and South America that included insecticides (IST; 999 mu g/m(3)) and incense (ICS; 145 mu g/m(3)), followed by traffic (216 mu g/m(3)) and cooking (150 mu g/m(3)). The lowest average 10 min concentrations were also observed in the same microenvironment lacking IST or ICS (<= 14 mu g/m(3)). With no use of specific products, office workers and students were the least exposed, and drivers and cooks were the most exposed. The concentrations are up to 7.5 and 3 times higher than the World Health Organization's yearly and daily recommended exposure levels, respectively, indicating the need to promptly elaborate and apply effective mitigation strategies to improve air quality and protect public health. This study highlights the importance of indoor air pollution sources related to culture and confirms previous studies on urban outdoor air pollution sources, especially in developing countries. The findings could be applied to cities other than Bamako, as similar practices and lifestyles are common in different cultures.

Automated summary

This study aimed to characterize personal exposure to PM2.5 in the city of Bamako, Mali. The findings revealed that different daily activities and microenvironments had an impact on PM2.5 concentrations, with insecticides, incense, traffic, and cooking identified as the main sources of exposure. The study also found that office workers and students had the lowest levels of exposure, while drivers and cooks had the highest levels. These concentrations exceeded the recommended exposure levels by the World Health Organization, highlighting the need for measures to improve air quality and protect public health.