Association between personal PM10 exposure and pulmonary function in healthy volunteers from a semi-arid city on the US-Mexican border

Abstract

Most studies about associations between exposures to PM10 and decreased pulmonary function do not consider people in good respiratory health and immediate (hours) effects of personal PM10 exposures. This study evaluated associations between personal PM10 exposures and pulmonary function (i.e., forced expiratory volume in one second or FEV1, forced vital capacity or FVC, and FEV1/FVC) in 97 healthy adult residents of Mexicali, Baja California, Mexico. Subjects used a personal environmental monitor that sampled PM10 every 5 min during the 24 h of their daily activities. Associations of personal-PM10 and pulmonary function were analyzed using multiple linear and linear-log regressions, with correction of serial autocorrelation, controlling for temperature, relative humidity, age, height, weight, body mass index, gender, and time. The largest statistically significant association was found between PM10 and FEV1, adjusting for age, height, and gender. FEV1 decreased –56.0 mL (95% CI: –107.0, –5.0 mL) per each increment of 10 µg/m3 of PM10 in air or –50.0 mL (95% CI: –92.0 mL, –9.0 mL) per each 20% increase in personal-PM10-concentration, when using linear or linear-log regression, respectively. No significant associations were found for FVC or FEV1/FVC ratio. The study showed that personal PM10 exposure in healthy adult volunteers from Mexicali was associated with small but significant decreases of FEV1; more significant when assessing the PM10 levels recorded sixteen hours before.