Serum angiotensin-converting enzyme and lysosomal enzymes in tobacco workers

The activities of angiotensin-converting enzyme (ACE) in people with extrinsic allergic alveolitis (EAA) have been both increased and decreased. These observations suggest that pulmonary macrophages or endothelial cells participate in the disease process. Exposure to molds in the tobacco industry has recently been suspected to be associated with chronic extrinsic allergic alveolitis. In the present study, we analyzed the serum activities of ACE and two lysosomal enzymes, beta-N-acetylglycosaminidase (NAG) and beta-glucuronidase (GLU), among 57 tobacco workers. The tobacco workers not exposed had serum ACE levels similar to those of the reference population workers not occupationally exposed to dust (N = 127). The tobacco workers' serum levels of NAG (16.0 +/- 2.0 units/L and GLU (2.4 +/- 0.7 units/L) were higher than among the referents (NAG, 9.1 +/- 2.0 units/L; GLU, 1.0 +/- 0.6 units/L; p less than 0.01). Fifteen tobacco workers with respiratory symptoms compatible with pulmonary diseases caused by organic dust had a trend toward increased ACE, NAG, and GLU levels. The mean level of ACE in serum was higher among the workers with (25.8 +/- 4.5 units/L) than among those without pulmonary fibrosis (20.7 +/- 7.5 units/L; p less than 0.025). The mean ACE level was also higher among workers with the highest exposure to molds (24.6 +/- 7.1 units/L) compared to those with the mildest exposure (18.3 +/- 5.7 units/L; p less than 0.05). Tobacco workers with or without antibodies against one or more microbes had similar mean levels of ACE, NAG, and GLU. All of these findings indicate that raw tobacco dust and its contaminants may cause allergic or toxic reactions or both, reflected by the serum levels of ACE, NAG, and GLU.