marginally significantP = 0.053
Multiple regression analysis showed a negative association between PM 2.5 exposure and FVC% predicted (− 2.81%, 95% CI − 5.27 to − 0.34%, P = 0.027) and a marginally significant negative correlation with FVC (− 114.38 ml, 95% CI − 230.36 to 1.59 ml, P = 0.053).