Liver functions in silica-exposed workers in Egypt: possible role of matrix remodeling and immunological factors.

BACKGROUND: Brick manufacturing constitutes an important industrial sector in Egypt with considerable exposure to silica. OBJECTIVES: We aimed for evaluating hepatic functions in silica-exposed workers in the clay brick industry, and the possible role of matrix remodeling and immunological factors. METHODS: A case-control study, 87 workers as exposed and 45 as control subjects. Questionnaire, clinical examination, and laboratory investigations: liver functions, matrix metalloproteinase-9, immunoglobulins G and E, and anti-liver kidney microsomal antibody. RESULTS: In the exposed workers, mean levels of liver functions, matrix metalloproteinase-9 (MMP-9), and IgG and IgE were significantly higher. In the silicotic subgroup the mean level of GGT was almost twice the level in the non-silicotic subjects. Logistic regression showed that abnormal GGT and ALT were associated with production workers. CONCLUSION: Workers in the clay brick industry showed evidence of liver disease that could be related to matrix remodeling.

Angiotensin-converting enzyme gene polymorphisms and hypertension in occupational noise exposure in Egypt.

BACKGROUND: The gene-environment interaction in the pathogenesis of hypertension has not been extensively studied in occupational noise. OBJECTIVES: The aim of this study was to determine the relationship between noise and hypertension in Egyptian workers, the interaction of angiotensin-converting enzyme (ACE) gene polymorphisms as modifiers, and the possible relationship between noise hearing impairment and hypertension. METHODS: Study subjects were divided into two groups depending on noise exposure level. The control group (n = 161) was exposed to noise intensity <85 dB and the exposed group (n = 217) was exposed to noise intensity ≧85 dB. A polymerase chain reaction was used to differentiate the various genotypes of ACE insertion/deletion (I/D) and ACE G2350A. RESULTS: Noise significantly increased the likelihood of hypertension. Carriers of the genotypes AG, GG, and DD were vulnerable to hypertension on noise exposure. No association between hypertension and hearing impairment or noise-induced hearing loss (NIHL) was found. CONCLUSION: Our results support the association between ACE gene polymorphisms and occurrence of hypertension in noise-exposed workers.