title: Oxidative Stress Biomarkers in Exhaled Breath of Workers Exposed to Crystalline Silica Dust by SPME-GC-MS.
abstract: BACKGROUND
  Silicosis is considered an oxidative stress related disease that can lead to the development of lung cancer. In this study, our purpose was to analysis of volatile organic compounds (VOCs) in the exhaled breath of workers exposed to silica containing dust and compare peak area of these compounds with silicosis patients and healthy volunteers (smokers and nonsmokers) groups.
  
  
  METHODS
  In this cross sectional case-control study, the exhaled breath of 69 subjects including workers exposed to silica (n=20), silicosis patient (n=4), healthy non-smoker (n=20) and healthy smoker (n=25) were analyzed. We collected breath samples using 3-liter Tedlar bags. The VOCs were extracted with solid phase micro-extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). Personal exposure intensity was measured according to NIOSH 7601 method. Respiratory parameters were measured using spirometry.
  
  
  RESULTS
  Seventy percent and 100% of the exposures to crystalline silica dust exceeded from 8 h TWA ACGIH TLVs in case and positive control groups, respectively. A significant negative correlation was found between dust exposure intensity and FEV1/FVC when exposure and positive control groups were studied in a group (r2=-0.601, P<0.001). Totally, forty VOCs were found in all exhaled breath samples. Among the VOCs, the mean of peak area acetaldehyde, hexanal, nonanal, decane, pentad cane, 2-propanol and 3-hydroxy-2-butanone were higher in exhaled breath of the workers exposed to silica and silicosis patient compared to the healthy smoker and nonsmoker controls. In some cases the difference was significant (P<0.05).
  
  
  CONCLUSIONS
  The analysis of some VOCs in exhaled breath of subjects is appropriate biomarker to determine of exposure to silica.
authors.affiliation: Department of Occupational Health, Social Determinants of Health Research Center, Birjand University of Medical Sciences, Birjand, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Jalali
authors.affiliation: Department of Occupational Health, School of Public Health, Yazd University of Medical Science, Yazd, Iran.
authors.forename: Mohammad Javad
authors.initials: MJ
authors.lastname: Zare Sakhvidi
authors.affiliation: Excellence Center for Occupational Health, Research Centre for Health Sciences, School of Public Health, Hamadan University of Medical Science, Hamadan, Iran. bahrami@umsha.ac.ir.
authors.forename: Abdulrahman
authors.initials: A
authors.lastname: Bahrami
authors.affiliation: Excellence Center for Occupational Health, Research Centre for Health Sciences, School of Public Health, Hamadan University of Medical Science, Hamadan, Iran.
authors.forename: Nima
authors.initials: N
authors.lastname: Berijani
authors.affiliation: Department of Biostatistics, School of Public Health, Research Centre for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Hussein
authors.initials: H
authors.lastname: Mahjub
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D015415:Biomarkers / Q000378:metabolism; D001944:Breath Tests; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004391:Dust; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008175:Lung Neoplasms / Q000209:etiology; D008875:Middle Aged; D009784:Occupational Diseases / Q000209:etiology; D016273:Occupational Exposure / Q000009:adverse effects*; D018384:Oxidative Stress; D012119:Respiration; D012822:Silicon Dioxide / Q000009:adverse effects*; D012829:Silicosis / Q000150:complications / Q000378:metabolism*; D055549:Volatile Organic Compounds / Q000009:adverse effects / Q000378:metabolism*
chemical_list: D000395:Air Pollutants, Occupational; D015415:Biomarkers; D004391:Dust; D055549:Volatile Organic Compounds; D012822:Silicon Dioxide
keywords: Biomarkers; Breath tests; Occupational exposure; Oxidative stress; Silicosis; Volatile organic compounds