Indoor particulate matter and lung function in children (original) (raw)

2019, Science of The Total Environment

People generally spend more time indoors than outdoors resulting in a higher proportion of exposure to particulate matter (PM) occurring indoors. Consequently, indoor PM levels, in contrast to outdoor PM levels, may have a stronger relationship with lung function. To test this hypothesis, indoor and outdoor PM 2.5 and fungal spore data were simultaneously collected from the homes of forty-four asthmatic children aged 10-16 years. An optical absorption technique was utilized on the collected PM 2.5 mass to obtain concentrations of black carbon (BC) and ultraviolet light absorbing particulate matter, (UVPM; a marker of light absorbing PM 2.5 emitted from smoldering organics). Enrolled children completed spirometry after environmental measurements were made. Given the high correlation between PM 2.5 , BC, and UVPM, principal component analysis was used to obtain uncorrelated summaries of the measured PM. Separate linear mixed-effect models were developed to estimate the association between principal components of the PM variables and spirometry values, as well as the uncorrelated original PM variables and spirometry values. A one-unit increase in the first principal component variable representing indoor PM (predominantly composed of UVPM and PM 2.5) was associated with 4.1% decrease (99% CI = −6.9, −1.4) in FEV 1 /FVC ratio. 11.3 μg/m 3 increase in indoor UVPM was associated with 6.4% and 14.7% decrease (99% CI = −10.4, −2.4 and 99% CI = −26.3, −2.9, respectively) in percent predicted FEV 1 /FVC ratio and FEF 25-75 respectively. Additionally, 17.7 μg/m 3 increase in indoor PM 2.5 was associated with 6.1% and 12.9% decrease (99% CI = −10.2, −1.9 and 99% CI = −24.9, −1.0, respectively) in percent predicted FEV 1 /FVC ratio and FEF 25-75 , respectively. Outdoor PM, indoor BC, and indoor fungal spores were not significantly associated with lung function.