Objective: Organic waste workers are exposed to high endotoxin levels that may result in respiratory health effects. This study describes changes in lung function and methacholine airway responsiveness over a workweek in household organic waste loaders.
Methods: Assessment of lung function and methacholine airway responsiveness before and after a workweek in six organic waste loaders with and ten loaders without regular respiratory symptoms. Methacholine responsiveness was expressed as dose-response slope, i.e. % fall in FEV(1) per mg methacholine compared to either the post-saline value (DRS(sal)), or the highest FEV(1) (DRS(max)).
Results: Monday morning, FEV(1) was similar in cases and controls. Over the workweek, FEV(1) and MMEF decreased slightly in both cases and controls (P > 0.10). In contrast, DRS increased in cases and decreased in control subjects (P < 0.10). The difference in % change of DRS was statistically significant after adjustment for smoking and age.
Conclusion: Our results suggest exaggeration of pre-existent airway inflammation during the workweek in organic waste loaders with regular respiratory symptoms. This needs confirmation in larger studies.