Background: About half of the world's population is exposed to smoke from burning biomass fuels at home. The high airborne particulate levels in these homes and the health burden of exposure to this smoke are well described. Burning unprocessed biological material such as wood and dried animal dung may also produce high indoor endotoxin concentrations.

Objective: In this study we measured airborne endotoxin levels in homes burning different biomass fuels.

Methods: Air sampling was carried out in homes burning wood or dried animal dung in Nepal (n = 31) and wood, charcoal, or crop residues in Malawi (n = 38). Filters were analyzed for endotoxin content expressed as airborne endotoxin concentration and endotoxin per mass of airborne particulate.

Results: Airborne endotoxin concentrations were high. Averaged over 24 hr in Malawian homes, median concentrations of total inhalable endotoxin were 24 endotoxin units (EU)/m(3) in charcoal-burning homes and 40 EU/m(3) in wood-burning homes. Short cooking-time samples collected in Nepal produced median values of 43 EU/m(3) in wood-burning homes and 365 EU/m(3) in dung-burning homes, suggesting increasing endotoxin levels with decreasing energy levels in unprocessed solid fuels.

Conclusions: Airborne endotoxin concentrations in homes burning biomass fuels are orders of magnitude higher than those found in homes in developed countries where endotoxin exposure has been linked to respiratory illness in children. There is a need for work to identify the determinants of these high concentrations, interventions to reduce exposure, and health studies to examine the effects of these sustained, near-occupational levels of exposure experienced from early life.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2920920PMC
http://dx.doi.org/10.1289/ehp.0901605DOI Listing

Publication Analysis

Top Keywords

airborne endotoxin
20
homes burning
16
burning biomass
16
endotoxin concentrations
12
homes
11
endotoxin
11
concentrations homes
8
biomass fuels
8
levels homes
8
wood dried
8

Similar Publications

Enhancing indoor air quality and cardiopulmonary health in patients with asthma by photocatalytic oxidation and filters air cleaner.

J Hazard Mater

November 2024

Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung City, Taiwan, ROC; Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung City, Taiwan, ROC; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung City 807, Taiwan, ROC; Research Center for Precision Environmental Medicine, Kaohsiung Medical University, Kaohsiung City, Taiwan, ROC; Institute of Wildlife Conservation, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung City, Taiwan, ROC. Electronic address:

Background: Air purifiers can enhance indoor air quality and health outcomes, and studies have primarily focused on filters and particulate matter (PM) in households. Photocatalytic oxidation (PCO) is a promising technique for eliminating gaseous pollutants and bioaerosols. However, no field study was conducted in household.

View Article and Find Full Text PDF

Airborne dust and bioaerosols in Canadian conventional and alternative houses for laying hens.

J Occup Environ Hyg

December 2024

Département de Biochimie, de Microbiologie et de Bio-informatique, Faculté des Sciences et de Génie, Université Laval, Quebec City, Quebec, Canada.

Awareness about laying hen welfare has led to the phase-out of conventional battery cages in favor of the adoption of alternative housing systems for egg production in many countries. However, the greater freedom of movement for animals and the presence of manure and litter (sawdust, straw, feathers, etc.) on the floor in some alternative housing systems may be suitable conditions for dusts, bacteria, and fungi to be aerosolized, raising concerns about indoor air quality and respiratory health of workers.

View Article and Find Full Text PDF

LPS-induced lung tissue-resident trained innate immunity provides differential protection against pneumococci and SARS-CoV-2.

Cell Rep

October 2024

McMaster Immunology Research Centre, Department of Medicine, and M. G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada. Electronic address:

Recent evidence indicates that tissue-resident innate immune memory and trained innate immunity (TII) can be induced centrally in myeloid cells within the bone marrow and locally in tissue-resident macrophages in respiratory mucosal tissues. However, it remains unclear whether acute exposure to airborne microbial components like lipopolysaccharide (LPS) induces lasting innate immune memory in airway macrophages and TII capable of protection against heterologous pathogens. Using a murine model, we demonstrate that acute LPS exposure leads to dynamic changes in the immune phenotype of airway macrophages that persist long after the acute inflammatory response has subsided.

View Article and Find Full Text PDF

TCA metabolism regulates DNA hypermethylation in LPS and -induced immune tolerance.

Proc Natl Acad Sci U S A

October 2024

Department of Pediatrics, The Global TB Program, William T Shearer Center for Immunobiology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030.

Severe and chronic infections, including pneumonia, sepsis, and tuberculosis (TB), induce long-lasting epigenetic changes that are associated with an increase in all-cause postinfectious morbidity and mortality. Oncology studies identified metabolic drivers of the epigenetic landscape, with the tricarboxylic acid (TCA) cycle acting as a central hub. It is unknown if the TCA cycle also regulates epigenetics, specifically DNA methylation, after infection-induced immune tolerance.

View Article and Find Full Text PDF

Influence of different cleaning methods on the concentration of airborne endotoxins and microbial aerosols in the oral clinical environment.

BMC Oral Health

September 2024

Department of Periodontal I/Hebei Key Laboratory of Stomatology/Hebei Technology Innovation Center of Oral Health, School and Hospital of Stomatology, Hebei Medical University, Room 408, Hospital of Stomatology Hebei Medeical University 383 Zhongshan East Road, Chang 'an District, Shijiazhuang, 050017, PR China.

Aim: This study aims to evaluate the effectiveness of various cleaning methods in reducing airborne endotoxin and microbial aerosols during oral cleaning procedures.

Method: Forty patients undergoing oral cleaning procedures were randomly assigned to one of four groups (n = 10 per group). Group A received strong suction alone; Group B received strong suction combined with an air disinfection machine; Group C received strong suction combined with a dental electric suction machine; Group D received strong suction in conjunction with both an air disinfection machine and a dental electric suction machine.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!