title: Does household use of biomass fuel cause lung cancer? A systematic review and evaluation of the evidence for the GBD 2010 study.
abstract: BACKGROUND
  Around 2.4 billion people use traditional biomass fuels for household cooking or heating. In 2006, the International Agency for Research on Cancer (IARC) concluded emissions from household coal combustion are a Group 1 carcinogen, while those from biomass were categorised as 2A due to epidemiologic limitations. This review updates the epidemiologic evidence and provides risk estimates for the 2010 Global Burden of Disease study.
  
  
  METHODS
  Searches were conducted of 10 databases to July 2012 for studies of clinically diagnosed or pathologically confirmed lung cancer associated with household biomass use for cooking and/or heating.
  
  
  RESULTS
  Fourteen eligible studies of biomass cooking or heating were identified: 13 had independent estimates (12 cooking only), all were case-control designs and provided 8221 cases and 11 342 controls. The ORs for lung cancer risk with biomass for cooking and/or heating were OR 1.17 (95% CI 1.01 to 1.37) overall, and 1.15 (95% CI 0.97 to 1.37) for cooking only. Publication bias was not detected, but more than half the studies did not explicitly describe a clean reference category. Sensitivity analyses restricted to studies with adequate adjustment and a clean reference category found ORs of 1.21 (95% CI 1.05 to 1.39) for men (two reports, compiling five studies) and 1.95 (95% CI 1.16 to 3.27) for women (five reports, compiling eight studies). Exposure-response evidence was seen for men, and higher risk for women in developing compared with developed countries, consistent with higher exposures in the former.
  
  
  CONCLUSIONS
  There is now stronger evidence for biomass fuel use causing lung cancer, but future studies need better exposure assessment to strengthen exposure-response evidence.
authors.affiliation: Department of Public Health and Policy, University of Liverpool, Liverpool, UK.
authors.forename: Nigel
authors.initials: N
authors.lastname: Bruce
authors.affiliation: Department of Public Health and Policy, University of Liverpool, Liverpool, UK.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Dherani
authors.affiliation: Environmental Health Sciences, School of Public Health, University of California Berkeley, California, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA Division of Epidemiology, Albert Einstein College of Medicine, Bronx, New York, USA.
authors.forename: H Dean
authors.initials: HD
authors.lastname: Hosgood
authors.affiliation: Maryland Institute for Applied Environmental Health, University of Maryland, School of Public Health, College Park, Maryland, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Sapkota
authors.affiliation: Environmental Health Sciences, School of Public Health, University of California Berkeley, California, USA.
authors.forename: Kirk R
authors.initials: KR
authors.lastname: Smith
authors.affiliation: International Agency for Research on Cancer, Lyon, France.
authors.forename: Kurt
authors.initials: K
authors.lastname: Straif
authors.affiliation: Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Lan
authors.affiliation: Department of Public Health and Policy, University of Liverpool, Liverpool, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Pope
mesh_terms: D016902:Air Pollution, Indoor / Q000009:adverse effects; D018533:Biomass; D003296:Cooking; D004736:Energy-Generating Resources; D005260:Female; D006361:Heating; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology*; D008297:Male; D014934:Wood
keywords: Clinical Epidemiology; Lung Cancer