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

Int J Occup Environ Health. 2014 Apr-Jun;20(2):146-56. doi: 10.1179/2049396714Y.0000000061. Epub 2014 Mar 24.

Abstract

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.

Keywords: Brick workers,; Immunoglobulins; Liver functions,; Matrix metalloproteinase-9,; Silica,.

MeSH terms

  • Adult
  • Air Pollutants, Occupational / toxicity*
  • Autoantibodies / blood
  • Body Mass Index
  • Case-Control Studies
  • Dust*
  • Egypt / epidemiology
  • Humans
  • Immunoglobulin E / blood
  • Immunoglobulin G / blood
  • Industry*
  • Liver / physiopathology*
  • Liver Function Tests
  • Male
  • Matrix Metalloproteinase 9 / blood
  • Middle Aged
  • Occupational Exposure / adverse effects*
  • Occupational Health
  • Silicon Dioxide / toxicity*
  • Smoking / epidemiology
  • Time Factors

Substances

  • Air Pollutants, Occupational
  • Autoantibodies
  • Dust
  • Immunoglobulin G
  • anti-liver kidney microsome antibody
  • Immunoglobulin E
  • Silicon Dioxide
  • Matrix Metalloproteinase 9