title: Synergistic impaired effect between smoking and manganese dust exposure on pulmonary ventilation function in Guangxi manganese-exposed workers healthy cohort (GXMEWHC).
abstract: OBJECTIVE
  The aims of this study were to investigate the effects of manganese (Mn) dust exposure on lung functions and evaluate the potential synergistic effect between smoking and Mn dust exposure among refinery workers.
  
  
  METHODS
  A retrospective study including 1658 workers in a ferromanganese refinery was conducted, with subjects who were from the Guangxi manganese-exposed workers healthy cohort (GXMEWHC). Based on the Mn manganese cumulative exposure index (Mn-CEI), all subjects were divided into the low exposure group (n = 682) and the high exposure group (n = 976). A pulmonary function test was performed using an electronic spirometer, including the values and percentages of FVC, FEV1, FEV1/FVC, MMEF, PEFR, MVV, respectively.
  
  
  RESULTS
  No significant effect of Mn dust exposure on the pulmonary function was found in the female workers (all p>0.05). However, there was an obvious decrease in the male workers in the high exposure group compared with those in the low exposure group (FVC -60 ml, FEV1 -120 ml, MMEF -260 ml/s, MVV -5.06 L, all p<0.05). In the high exposure group, the reduction in FVC% predicted, MMEF and MMEF% predicted was 1.0%, 210 mL/s, and 4.9%, respectively. In particular, among the exposed subjects smokers had a statistically significant decrease in lung function compared with non-smokers and the reduction in FVC% predicted, MMEF and MMEF% predicted was 1.0%, 210 mL/s, and 4.9%, respectively (p<0.05). Partial correlation analysis showed that there was also negative correlation between Mn-CEI and decreased changes in MMEF (r = -0.159, p = 0.018) and also MMEF% predicted (r = -0.163, p = 0.015).
  
  
  CONCLUSIONS
  Mn dust can impair the pulmonary ventilation function of male workers but not females, and individual smoking habits and manganese exposure had a synergistic effect on the lung function decrease.
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Fenfen
authors: F
authors: Wang
authors: Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Yunfeng
authors: Y
authors: Zou
authors: Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors: Yuefei
authors: Y
authors: Shen
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Yaoqiu
authors: Y
authors: Zhong
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Yingnan
authors: Y
authors: Lv
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Damin
authors: D
authors: Huang
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Kangcheng
authors: K
authors: Chen
authors: Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Qin
authors: Q
authors: Li
authors: Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Li
authors: L
authors: Qing
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Bing
authors: B
authors: Xia
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Cheng
authors: C
authors: Su
authors: Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China.
authors: Shuyan
authors: S
authors: Ma
authors: Department of occupational health and environmental health, School of Public Health, Guangxi Medical University, Nanning, Guangxi, China; Center for Genomic and Personalized Medicine, Guangxi Medical University, Nanning, Guangxi, China.
authors: Xiaobo
authors: X
authors: Yang
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D004391:Dust; D005260:Female; D006801:Humans; D008297:Male; D008345:Manganese / Q000009:adverse effects*; D008669:Metallurgy; D016273:Occupational Exposure / Q000009:adverse effects*; D012123:Pulmonary Ventilation / Q000187:drug effects / Q000502:physiology*; D012129:Respiratory Function Tests / Q000379:methods / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects*; D013147:Spirometry; D011795:Surveys and Questionnaires
chemical_list: D004391:Dust; D008345:Manganese