Self-reported work activities, mucus membrane symptoms, and respiratory health outcomes among an industrial hog operation worker cohort, North Carolina, USA

BackgroundRespiratory disease among industrial hog operation (IHO) workers is well documented; however, it remains unclear whether specific work activities are more harmful and if personal protective equipment (PPE), as used by workers, can reduce adverse health outcomes.ObjectivesTo assess the relationship between self-reported IHO work activities and PPE use with mucus membrane and respiratory health symptoms in an occupational cohort.MethodsIHO workers (n=103) completed baseline and up to eight bi-weekly (i.e., every two weeks) study visits. Workers reported typical (baseline) and transient (bi-weekly) work activities, PPE use, and physical health symptoms. Baseline and longitudinal associations between work activities and health outcomes were assessed using generalized logistic and fixed-effects logistic regression models, respectively.ResultsAt baseline, reports of ever versus never drawing pig blood, applying pesticides, and increasing years worked at any IHO were positively associated with reports of eye, nose, and/or throat irritation. Over time, transient exposures, including those associated with dustiness in barns, cleaning of barns, and pig contact were associated with increased odds of symptoms including sneezing, headache, and eye or nose irritation, particularly in the highest categories of exposure. When PPE was used, workers had decreased odds of symptoms interfering with sleep (odds ratio (OR): 0.1; 95% confidence interval (CI): 0.01, 0.8), sneezing (OR: 0.1; 95% CI: 0.01, 1.0), and eye or nose irritation (OR: 0.1; 95% CI: 0.02, 0.9). Similarly, when they washed their hands ≥8 times per shift (the median) versus less frequently, workers had decreased odds of any respiratory symptom (OR: 0.3; 95% CI: 0.1, 0.8).DiscussionIn this healthy volunteer IHO worker population, increasingly unfavorable work activities were associated with self-reported mucus membrane and respiratory health outcomes. Strong protective associations were seen between PPE use and handwashing and the odds of symptoms, warranting further investigation in intervention studies.