No association between in utero exposure to emissions from a coalmine fire and post-natal lung function

BACKGROUND AND OBJECTIVE: Studies linking early life exposure to air pollution and subsequent impaired lung health have focused on chronic, low-level exposures in urban settings. We aimed to determine whether in utero exposure to an acute, high-intensity air pollution episode impaired lung function 7-years later. METHOD: We conducted a prospective cohort study of children who lived in the vicinity of a coalmine fire. Respiratory function was measured using the forced oscillation technique (FOT). Z-scores for resistance at 5 Hz (R(5)), reactance at 5 Hz (X(5)) and area under the reactance curve (AX) were calculated. Two sets of analyses were conducted to address two separate questions: (1) whether mine fire exposure (a binary indicator; conceived after the mine fire vs in utero exposed) was associated with the respiratory Z-scores; (2) whether there was any dose–response relationship between fire-related PM(2.5) exposure and respiratory outcomes among those exposed. RESULTS: Acceptable lung function measurements were obtained from 79 children; 25 unexposed and 54 exposed in utero. Median (interquartile range) for daily average and peak PM(2.5) for the exposed children were 4.2 (2.6 – 14.2) and 88 (52—225) µg/m(3) respectively. There were no detectable differences in Z-scores between unexposed and exposed children. There were no associations between respiratory Z-scores and in utero exposure to PM(2.5) (daily average or peak). CONCLUSION: There was no detectable effect of in utero exposure to PM(2.5) from a local coalmine fire on post-natal lung function 7-years later. However, statistical power was limited. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12890-023-02414-7.