title: A dynamic smoke generation and nose-only inhalation exposure system for rats: preliminary results from studies of selected transportation materials.
abstract: BACKGROUND
  Smoke inhalation injury is the main cause of fatalities for fire victims. Understanding in the pathophysiology of the injury has not been fully explored in recent years. To further explore the pathophysiological mechanism, a dynamic and controllable animal model is necessary.
  
  
  OBJECTIVE
  To develop a rat model of smoke inhalation injury to simulate human victims in air-restricted vehicle cabin fires.
  
  
  METHODS
  Smoke concentration, including CO, O2, VOCs and smoke temperature under different combustion conditions, were detected. Levels of COHb, respiratory function, lung wet-to-dry weight ratio and protein concentration in BALF and blood were measured. Pathological evaluations of lung in tissues were conducted at 1, 6, 24 and 48 h post-exposure.
  
  
  RESULTS
  Smoke concentration rose with the increase of combustion temperature and decrease of oxygen flow. Further, 215 kinds of VOCs in the smoke were detected, and the concentrations of benzene, methylbenzene, ethylbenzene, dimethylbenzene, phenylethylene and trimethylbenzene was 32.93, 402.06, 764.03, 113.73, 1006.61 and 89.28 mg/m(3), respectively. Significant hypoxemia and CO poisoning occurred in rats. The FCOHb after exposure for 14 min immediately rose to (44.2 ± 12.3) % and then gradually decrease to a normal level at 300 min post-exposure. At 24 h post-exposure, Penh increased significantly (p < 0.05), and high pulmonary vascular permeability and significant lung edema (p < 0.05) were observed in the smoke inhalation group.
  
  
  CONCLUSIONS
  In summary, the novel rat model of smoke inhalation injury system used in the study is dynamic and controllable, and appropriate for use in smoke inhalation injury studies of air-restricted cabins in vehicles.
authors.affiliation: Institute of Toxicology, National Experimental Teaching Demonstrating Center, Third Military Medical University , Chongqing , China and.
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Zhao
authors.forename: Daibo
authors.initials: D
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Cai
authors.forename: Hui
authors.initials: H
authors.lastname: An
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Cui
authors.forename: Huan
authors.initials: H
authors.lastname: Yang
authors.forename: Fei
authors.initials: F
authors.lastname: Han
authors.forename: Lin
authors.initials: L
authors.lastname: Ao
authors.forename: Jinyi
authors.initials: J
authors.lastname: Liu
authors.forename: Jia
authors.initials: J
authors.lastname: Cao
mesh_terms: D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects; D002263:Carboxyhemoglobin / Q000378:metabolism; D004195:Disease Models, Animal; D008168:Lung / Q000187:drug effects / Q000473:pathology; D008297:Male; D018986:Motor Vehicles; D051381:Rats; D017207:Rats, Sprague-Dawley; D012906:Smoke / Q000009:adverse effects* / Q000032:analysis; D015208:Smoke Inhalation Injury / Q000503:physiopathology*
chemical_list: D012906:Smoke; D002263:Carboxyhemoglobin
keywords: Air-restricted cabin; animal model; nose-only; rat; smoke inhalation injury