title: Household air pollution and the lung microbiome of healthy adults in Malawi: a cross-sectional study.
abstract: Domestic combustion of biomass fuels, such as wood, charcoal, crop residue and dung causes Household Air Pollution (HAP). These inhaled particulates affect more than half of the world's population, causing respiratory problems such as infection and inflammatory lung disease. We examined whether the presence of black carbon in alveolar macrophages was associated with alterations in the lung microbiome in a Malawi population.
  
  
  
  Bronchoalveolar lavage samples from 44 healthy adults were sequenced using 16S rDNA amplification to assess microbial diversity, richness and relative taxa abundance. Individuals were classified as high or low particulate exposure as determined by questionnaire and the percentage of black carbon within their alveolar macrophages.
  
  
  
  Subjects in the low and high particulate groups did not differ in terms of source of fuels used for cooking or lighting. There was no difference in alpha or beta diversity by particulate group. Neisseria and Streptococcus were significantly more abundant in samples from high particulate exposed individuals, and Tropheryma was found less abundant. Petrobacter abundance was higher in people using biomass fuel for household cooking and lighting, compared with exclusive use of electricity.
  
  
  
  Healthy adults in Malawi exposed to higher levels of particulates have higher abundances of potentially pathogenic bacteria (Streptococcus, Neisseria) within their lung microbiome. Domestic biomass fuel use was associated with an uncommon environmental bacterium (Petrobacter) associated with oil-rich niches.
authors: Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK. jamie.rylance@lstmed.ac.uk.|Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi. jamie.rylance@lstmed.ac.uk.
authors: Jamie
authors: 0000-0002-2323-3611
authors: J
authors: Rylance
authors: Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.
authors: Anstead
authors: A
authors: Kankwatira
authors: Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA.
authors: David E
authors: DE
authors: Nelson
authors: Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, USA.
authors: Evelyn
authors: E
authors: Toh
authors: Department of Medicine, Indiana University, Indianapolis, IN, USA.
authors: Richard B
authors: RB
authors: Day
authors: Center for Biomedical Informatics, Department of Public Health Sciences, Loyola University Chicago, Maywood, IL, 60153, USA.
authors: Huaiying
authors: H
authors: Lin
authors: Center for Biomedical Informatics, Department of Public Health Sciences, Loyola University Chicago, Maywood, IL, 60153, USA.
authors: Xiang
authors: X
authors: Gao
authors: Center for Biomedical Informatics, Department of Public Health Sciences, Loyola University Chicago, Maywood, IL, 60153, USA.
authors: Qunfeng
authors: Q
authors: Dong
authors: The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, 06032, USA.
authors: Erica
authors: E
authors: Sodergren
authors: The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut, 06032, USA.
authors: George M
authors: GM
authors: Weinstock
authors: Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.
authors: Robert S
authors: RS
authors: Heyderman
authors: Department of Medicine, Indiana University, Indianapolis, IN, USA.
authors: Homer L
authors: HL
authors: Twigg
authors: Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.|Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.
authors: Stephen B
authors: SB
authors: Gordon
mesh_terms: D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects / Q000032:analysis*; D018893:Bronchoalveolar Lavage / Q000379:methods; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D002244:Carbon / Q000032:analysis / Q000493:pharmacokinetics; D003296:Cooking / Q000379:methods; D003430:Cross-Sectional Studies; D005260:Female; D005579:Fossil Fuels / Q000009:adverse effects / Q000032:analysis; D006798:Housing; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D016676:Macrophages, Alveolar / Q000737:chemistry / Q000378:metabolism; D008295:Malawi; D008297:Male; D064307:Microbiota; D052638:Particulate Matter / Q000009:adverse effects / Q000032:analysis*; D012959:Socioeconomic Factors
chemical_list: D005579:Fossil Fuels; D052638:Particulate Matter; D002244:Carbon
keywords: Alveolar macrophage; Household air pollution; Petrobacter; Respiratory microbiome