Moshe Stark

Detection of occult lung impairment in welders by induced sputum particles and breath oxidation

BACKGROUND We evaluated particulate matter in combined induced sputum (IS) and oxidation in exhaled breath condensate (EBC) to test whether underlying inflammatory changes are present in asymptomatic welders. METHODS Thirty welders from the Israel Defense Forces exposed to aluminum/iron (Group 1) or to cadmium/chromium/iron/lead/nickel (Group 2, N = 16) and 27 non-exposed administrators were studied. IS was recovered, particle size distribution, hydrogen peroxide and pH were measured, and exhaled breath condensate was collected. RESULTS Group 2 had a higher % neutrophils than all other participants (P = 0.0001) and a higher % particles >2 microm in diameter (P = 0.0017). Percent particles and years of exposure highly correlated (P = 0.051). All welders EBC samples had higher concentrations of hydrogen peroxide than controls (P = 0.0001). pH was lower only for Group 2 (P = 0.0001). CONCLUSIONS Combined IS and EBC measurements detect underlying inflammation in airways of asymptomatic welders. It emerged that airway inflammation is present in asymptomatic welders, and that the particle burden, inflammatory cells, and level of oxidative stress are a function of the type and the duration of welding. Am. J. Ind. Med. 51:503-511, 2008.

A Novel Alternative to Environmental Monitoring to Detect Workers at Risk for Beryllium Exposure-Related Health Effects

The purpose of this study was to describe a methodology for surveillance and monitoring of beryllium exposure using biological monitoring to complement environmental monitoring. Eighty-three Israeli dental technicians (mean age 41.6 ± 1.36 years) and 80 American nuclear machining workers (54.9 ± 1.21 years) were enrolled. Biological monitoring was carried out by analyzing particle size (laser technique) and shape (image analysis) in 131/163 (80.3%) induced sputum samples (Dipa Analyser, Donner Tech, Or Aquiva, Israel). Environmental monitoring was carried out only in the United States (Sioutas impactor, SKC, Inc., Eighty Four, Pa.). Pulmonary function testing performance and induced sputum retrieval were done by conventional methods. Sixty-three Israeli workers and 37 American workers were followed up for at least 2 years. Biological monitoring by induced sputum indicated that a >92% accumulation of <5 μm particles correlated significantly to a positive beryllium lymphocyte proliferation test result (OR 3.8, 95% CI 1.2–11.4, p = 0.015) among all participants. Environmental monitoring showed that beryllium particles were <1 μm, and this small fraction (0.1–1 μ) was significantly more highly accumulated in nuclear machining workers compared to dental technicians. The small fractions positively correlated with induced sputum macrophages (r = 0.21 p = 0.01) and negatively correlated with diffusion lung carbon monoxide single breath (DLCO-SB r = 0.180 p = 0.04) in all subjects. Years of exposure were positively correlated to the number of accumulated particles 2–3 μ in diameter (r = 0.2, p = 0.02) and negatively correlated to forced expiratory volume in one second/forced vital capacity findings (r = −0.18, p = 0.02). DLCO was decreased in both groups after two years of monitoring. Biological monitoring is more informative than environmental monitoring in the surveillance and monitoring of workers in beryllium industries. Induced sputum is a feasible and promising biomonitoring method that should be included in the surveillance of exposed workers.

Aging leads to impaired epicutaneous sensitization that causes attenuated allergy and pulmonary inflammation in mice

Aging is associated with altered decreased barrier function in the skin, which can lead to different types of immunoglobulin E (IgE)‐mediated sensitization to environmental allergens. Yet, allergen‐specific respiratory sensitization among the elderly is not well described. The aim of this study was to investigate the effect of aging on allergic pulmonary inflammation induced by epicutaneous sensitization of mechanically irritated skin in mice. For this purpose, 6‐week‐, 6‐month‐, and 18‐month‐old female BALB/c mice, underwent epicutaneous sensitization with ovalbumin (OVA) or phosphate buffered saline (PBS), followed by an inhaled OVA challenge. Blood OVA‐specific IgE levels measured after epicutaneous sensitization, as well as, bronchial alveolar lavage fluids (BALF) leucocyte, eosinophil, and cytokine levels measured after OVA inhalation challenge were similar among the 6‐week‐old (young) and 6‐month‐old (adult) groups. However, significantly decreased levels of systemic OVA IgE, and BALF leukocyte, eosinophil and T helper cell type 2 cytokine levels, were measured after OVA inhalation challenge in elderly (18‐month‐old) mice compared to the other groups of mice. In addition, interleukin‐10 (IL‐10), a regulatory suppressor cytokine, was more abundant in the BALF of the elderly group after epicutaneous sensitization and inhalation challenge. Our results suggest that elderly mice have a reduced allergic response to induced sensitization with OVA, possibly regulated by increased IL‐10 levels.