Exposure to lead and its effect on sleep quality and digestive problems in soldering workers

  • Mahmoud Mohammadyan
  • Mahmood Moosazadeh
  • Abasalt Borji
  • Narges Khanjani
  • Somayeh Rahimi MoghadamEmail author


Some studies show that exposure to lead affects sleep quality and causes digestive disorders. The aim of this study was to evaluate the quality of sleep and digestive disorders in solderers exposed to lead. In a cross-sectional study, the occupational exposure of 40 soldering workers to lead fume and their blood lead levels were measured in the electronics industry of Neyshabur city, according to standard methods. The sleep quality of workers was measured by the Pittsburgh Sleep Quality Index (PSQI) questionnaire and their digestive disorders were recorded in a checklist. This study showed that 67.5% of subjects had poor sleep quality. There was a significant relation between sleep quality, air lead (p = 0.02), and blood lead (p = 0.03). Bad sleep quality was 2.4 times higher in subjects exposed to lead above the threshold (p = 0.03). 92.5% of the population under study suffered from at least one digestive disorder. Digestive disorders such as hiccupping (85%) and nausea (67%) were more common among the workers, and their odds was 3.09 and 2.00 times higher in workers exposed to lead above the threshold, compared with others. Bad sleep quality and gastrointestinal disorders were prevalent among workers exposed to lead. The results of this study confirm the need for further research about the side effects of lead on humans. It also clarifies the need for a revision in the recommended occupational exposure level for lead.


Lead Electronics industry Soldering Sleep hygiene Gastrointestinal disorders 



The authors thank Dr. Abedi, PhD in Analytical Chemistry and the Simorgh Pharmaceutical Industry which helped us prepare and analyze the samples.

Funding information

This study was conducted with the financial support of Mazandaran University of Medical Sciences and Neyshabur University of Medical Sciences, and by grant number 3036-96.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Health Science Research Center, Addiction InstituteMazandaran University of Medical SciencesSariIran
  2. 2.Basic Sciences DepartmentNeyshabur University of Medical SciencesNeyshaburIran
  3. 3.Environmental Health Engineering Research CenterKerman University of Medical ScienceKermanIran
  4. 4.Student Research Committee, Health Sciences Research Center, Faculty of HealthMazandaran University of Medical SciencesSariIran

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