Residential environment,indoor air pollution and risk of lung cancer:a case-control study

Objective To investigate the relationship between residential environment,indoor air pollution and the incidence of lung cancer.Methods A case-control study was conducted among 1 374 first pathologically confirmed lung cancer patients in three general hospitals in Fuzhou city of Fujian province (the First Affiliated Hospital of Fujian Medical University,Fujian Medical University Union Hospital,and Fuzhou General Hospital of Nanjing Military Command) and 1374 gender and age (±2 years) frequency-matched healthy permanent residents (living in Fuzhou city more than 10 years) who visited departments other than oncology department at the same hospital as the cases during the same period from January 2006 to December 2014.Epidemiological data were collected with an in-person interview using a standard questionnaire.Results Compared to those in the controls,significantly higher ratios were reported in the cases for exposures to exhausted gas (10.2% vs.4.2%),waste water (3.2% vs.0.9%),dust (2.2% vs.0.5%),mixed pollution (2.6% vs.0.7%),other pollution (1.5% vs.0.6%),passive smoking at home (46.5% vs.25.7%),using coal as cooking fuel 10 years ago (40.2% vs.22.9%),using coal as cooking fuel during recent 10 years (11.6% vs.5.2%),light smokiness during cooking (54.7% vs.48.3%),medium smokiness during cooking (23.8% vs.18.7%),heavy smokiness during cooking (4.5% vs.1.7%),with a kitchen not separated from bedroom (2.9% vs.1.5%),normal residential ventilation (18.5% vs.9.0%),and insufficient residential ventilation (3.3% vs.1.2%)(P<0.05 for all);whereas significantly lower proportions were reported in the cases for using a ventilator in kitchen (58.8% vs.75.3%),keeping proper oil temperature during cooking (63.3% vs.70.2%),and living in a storied building (67.6% vs.86.8%)(P<0.05 for all).After adjusting for confounding factors including gender,age,nationality,education,marital status,body mass index,smoking status,exposure history of occupational risk factors,family history of cancer,and history of lung diseases,the results of multivariate unconditional logistic regression analyses indicated that exposure to exhaust gas,waste water,dust,mixed pollution,passive smoking at home,using coal as cooking fuel 10 years ago,smokiness during cooking,and insufficient residential ventilation were risk factors of lung cancer;while keeping proper oil temperature during cooking and living in a storied building were protective factors of lung cancer incidence.Conclusion Residential environment and indoor air pollution could increase the risk of lung cancer.