Differential exposure and acute health impacts of inhaled solid-fuel emissions from rudimentary and advanced cookstoves in female CD-1 mice.
Gibbs-Flournoy, E., Ian Gilmour, M. Higuchi, Jim Jetter, I. George, L. Copeland, R. Harrison, V. Moser, AND J. Dye. Differential exposure and acute health impacts of inhaled solid-fuel emissions from rudimentary and advanced cookstoves in female CD-1 mice. ENVIRONMENTAL RESEARCH. Academic Press Incorporated, Orlando, FL, 161:35-48, (2018).
Air pollution is a global public health problem to which emissions from rudimentary cooking devices contribute significantly. Associated acute health effects include respiratory and eye irritation, headache, cough, acute lower respiratory infection and severe pneumonia in children. The present study was designed to further assess differential exposure and acute respiratory system effects of inhaled CS emissions. We exposed healthy female outbred (CD-1) mice to emissions from the same stoves and wood used by Mutlu et al (2016). We compared the results to those of mice inhaling filtered air. Assessments included: (1) characterization of CS emissions, (2) biomarkers of exposure, and (3) health effects related to altered behavior, pulmonary function, innate immunity, and development of lung injury, inflammation, oxidative stress, or upregulation of adaptive genes.
Background: There is an urgent need to provide access to cleaner end user energy technolo-gies for the nearly 40% of the world’s population who currently depend on rudimentary cooking and heating systems. Advanced cookstoves (CS) are de¬signed to cut emissions and solid-fuel consump¬tion, thus reducing adverse human health and environ¬mental impacts. Study premise: We hypothesized that, compared to a traditional (Tier 0) three-stone (3-S) fire, acute inhala¬tion of solid-fuel emissions from advanced natural-draft (ND; Tier 2) or forced-draft (FD; Tier 3) stoves would reduce exposure biomarkers and lessen pulmonary and innate immune system health effects in exposed mice. Results: Across two simulated cooking cycles (duration~3h), emitted particulate mass concen¬trations were reduced 80% and 62% by FD and ND stoves, respectively, compared to the 3-S fire; with corre¬spond¬ing decreases in particles visible within murine alveolar macrophages. Emitted carbon monox¬ide was reduced ~90% and ~60%, respectively. Only 3-S-fire-exposed mice had increased carbox¬yhemoglobin levels. Emitted volatile organic com-pounds were FD<<3-S-fire ≤ND stove; increased expression of genes involved in xenobiotic metabolism (COX-2, NQO1, CYP1a1) was detected only in ND- and 3-S-fire-exposed mice. Diminished macro¬phage phag¬o¬cytosis was observed in the ND group. Lung glutathione was significantly depleted across all CS groups, however the FD group had the most severe, ongoing oxidative stress. Conclusions: These results are consistent with reports associating exposure to solid fuel stove emissions with modu¬la¬tion of the innate immune system and increased suscep¬tibility to infection. Lower respiratory infections continue to be a leading cause of death in low-income economies. Notably, 3-S-fire-exposed mice were the only group to develop acute lung injury, possibly because they inhaled the highest concentra¬tions of hazardous air toxicants (e.g., 1,3-butadiene, toluene, ben¬zene, acrolein) in association with the greatest number of particles, and particles with the highest % organic car¬bon. However, no Tier 0 to 3 ranked CS group was without some untoward health effect indicating that access to still cleaner, ideally renewable, energy technologies for cooking and heating is warranted.
Record Details:Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Organization:U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LABORATORY
ENVIRONMENTAL PUBLIC HEALTH DIVISION
CARDIOPULMONARY AND IMMUNOTOXICOLOGY BRANCH