Polychlorinated biphenyls, glycaemia and diabetes in a population living in a highly polychlorinated biphenyls-polluted area in northern Italy: a cross-sectional and cohort study

  • Claudia Zani
    Department of Experimental and Applied Medicine, Section of Hygiene, Epidemiology and Public Health, University of Brescia, Italy.
  • Francesco Donato
    Department of Experimental and Applied Medicine, Section of Hygiene, Epidemiology and Public Health, University of Brescia, Italy.
  • Michele Magoni
    Brescia Local Health Authority, Italy.
  • Donatella Feretti
    Department of Experimental and Applied Medicine, Section of Hygiene, Epidemiology and Public Health, University of Brescia, Italy.
  • Loredana Covolo
    Department of Experimental and Applied Medicine, Section of Hygiene, Epidemiology and Public Health, University of Brescia, Italy.
  • Francesco Vassallo
    Brescia Local Health Authority, Italy.
  • Fabrizio Speziani
    Brescia Local Health Authority, Italy.
  • Carmelo Scarcella
    Brescia Local Health Authority, Italy.
  • Roberto Bergonzi
    Institute of Occupational Health and Industrial Hygiene, University of Brescia, Italy.
  • Pietro Apostoli
    Institute of Occupational Health and Industrial Hygiene, University of Brescia, Italy.

ABSTRACT

Background. Polychlorinated biphenyls (PCBs) have been found to be associated with diabetes in some, but not all, studies performed so far. The aim of this study was to assess the association between PCB serum levels and glycaemia and diabetes in people living in Brescia, a highly industrialised PCB-polluted town in Northern Italy. Design and Methods. 527 subjects were enrolled in a cross-sectional population-based study: they were interviewed face-to-face in 2003 and also provided a blood sample under fasting conditions. The concentration of 24 PCB congeners was determined using gas-chromatography (GC/MS). Subsequently, all subjects were included in a follow-up (cohort) study. According to the Local Health Authority health-care database, subjects were considered to be diabetic if they had diabetes at interview time (prevalent cases) or during a 7-year follow-up (incident cases). Results. A total of 53 subjects (10.0%) were diabetics: 28 had dia- betes at enrolment and other 25 developed the disease subsequently. Diabetes frequency increased according to the serum concentrations of total PCBs and single PCB congeners, but no association was found when estimates were adjusted for education, body mass index, age and gender by logistic regression analysis. Accordingly, glycaemia increased with PCB serum levels, but no association was observed when multiple regression analysis, including confounding factors, was performed. Conclusions. This study does not support the hypothesis that PCB environmental exposure is strictly associated with diabetes or glycaemia.

AUTHOR BIOGRAPHY

Claudia Zani, Department of Experimental and Applied Medicine, Section of Hygiene, Epidemiology and Public Health, University of Brescia