Cross-Shift Changes in Pulmonary Function and Occupational Exposure to Particulate Matter among E-Waste Workers in Ghana

Abstract

Objectives: To examine the association between cross-shift changes in pulmonary function (PF) and personal inhalation exposure to particulate matter (PM) among informal electronic-waste (e-waste) recovery workers with substantial occupational exposure to airborne pollutants from burning and other e-waste recovery activities.Methods: Using a cross-shift design, pre- and post-shift spirometry and concomitant personal inhalation exposure to personal PM (sizes <1, < 2.5, and the coarse fraction, 10-2.5 µm in aerodynamic diameter) were measured among e-waste workers (n=142) at the Agbogbloshie e-waste site and a comparison population (n=65) in Accra, Ghana. Linear mixed models measured associations between percent changes in PF and personal PM; self-reported exposures; and (image-based) activities. Results: Following 4 hour (+ 44 min) work-shifts, decelerations in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) per hour were observed among e-waste workers (2.2% and 1.2%, respectively) and the reference population (1.5% and 0.8%, respectively). Despite significantly higher concentrations of personal PM (all sizes) among e-waste workers, increases in PM (all sizes) were not associated with decelerations in PF in either group. Indicative of a lag-effect, e-waste workers who worked “yesterday” had a larger decrement in FVC (2.4%, 95%CI: -4.04, -0.81) in comparison to those that did not work “yesterday”.Conclusions: The acute respiratory-related health effects due to PM exposure among e-waste workers remains unclear. Limitations included potential selection bias due to the “healthy worker” effect and challenges in eliciting valid PF assessments among e-waste workers, short shift duration, the lack of an inception cohort, and inability to measure pre-shift PF among e-waste workers who sleep at the site (89%). Cross-shift studies are useful for generating robust evidence in traditional work settings; however, they need to be adapted to informal settings where workers do not “clock-in” at the start of a shift.