Publications

BACKGROUND

Cleaning workers are regularly exposed to cleaning products containing hazardous chemicals. This study investigated acute symptoms associated with chemical exposures among cleaning workers and their safe work practices.

METHODS

This cross-sectional study included 183 cleaning workers employed in an academic medical center and affiliated health sciences campuses in Northern California. Data on respiratory, eye, skin, neurological, and gastrointestinal symptoms and occupational factors were collected by in-person interviews or self-administered questionnaires.

RESULTS

Chemical-related symptoms (several times monthly or more often) were more common among workers who performed patient area cleaning (44%) than hospital custodians (36%) or campus custodians (28%). After controlling for age, sex, and job title, symptoms were associated with exposure to carpet cleaners (OR = 2.98, 95% CI 1.28-6.92), spray products (OR = 2.82, 95% CI 1.16-6.82), solvents (OR = 2.71, 95% CI 1.20-6.15), and multi-purpose cleaners (OR = 2.58, 935% CI 1.13-6.92). Except for gloves, regular use of personal protective equipment was infrequent.

CONCLUSIONS

Study findings suggest a need for additional interventions such as use of less toxic products to reduce health risks among cleaning workers.

RATIONALE

Activation of type 2 cytokine pathways plays a central role in a large subset of subjects with asthma. Th2-high and Th2-low asthma have distinct clinical, pathologic, and molecular phenotypes and respond differently to therapy. The factors that initiate type 2 responses in some subjects with asthma are unknown.

OBJECTIVES

To determine whether expression of epithelial cytokines IL-25, IL-33, and thymic stromal lymphopoietin are associated with type 2 responses and predict response to inhaled corticosteroid (ICS) in asthma.

METHODS

We analyzed pulmonary function tests, blood, and bronchoscopic biopsies from 21 healthy control subjects and 43 subjects with asthma. Subjects with asthma underwent an 8-week treatment with inhaled budesonide.

MEASUREMENTS AND MAIN RESULTS

Epithelial expression of IL-25, but not IL-33 or thymic stromal lymphopoietin, was increased in a subset of subjects with asthma. The IL-25-high subset had greater airway hyperresponsiveness, more airway and blood eosinophils, higher serum IgE, more subepithelial thickening, and higher expression of Th2 signature genes. ICS improved FEV1 and hyperresponsiveness in the IL-25-high but not the IL-25-low subset. Plasma IL-25 levels correlated with epithelial IL-25 expression, airway eosinophilia, and beneficial responses to ICS treatment.

CONCLUSIONS

IL-25 measurements identify two subsets of subjects with distinct asthma phenotypes and different responses to ICS. Because IL-25 has a major role in triggering type 2 responses, bronchial epithelial IL-25 expression is likely a key determinant of type 2 response activation in asthma. Plasma IL-25 level reflects airway IL-25/type 2 response activation and may be useful for predicting responses to asthma therapy.