Levels of indoor particulate matter and association with asthma in children in Benin City, Nigeria

The relationship between indoor particulate matter and asthma in children was assessed in this study. Forty-five (45) locations were randomly selected across the five local government areas in Benin City, Edo State, for air quality assessment. Indoor and outdoor particulates (PM 1.0 , PM 2.5 , and PM 10 ) were monitored monthly using a handheld BLATN particulate sampler (Br-Smart-126S series). Reported clinical cases of asthma in children from 2008 to 2017 were collected from two major hospitals in the metropolis. The data obtained were analysed with SPSS for Windows version 21.0. The average concentrations of indoor and ambient PM ranged between 10.7–26.2 and 19.0–49.4 µg/m 3 (PM 1.0 ), 27.4–59.6 and 45.6–93.0 µg/m 3 (PM 2.5 ), and 33.5–67.9 and 60.9–106.1 µg/m 3 (PM 10 ) in the wet and dry seasons. PM 2.5 and PM 10 concentrations were observed above the WHO standards. Indoor particulate concentration was significantly ( p = 0.001–0.012) higher in the dry season across the locations. Outdoor PM correlated positively ( R = 0.568–0.855, p