Toxic pulmonary edema due to inhalation of pyrolyzed polytetrafluoroethylene products in lab animals

Relevance. Thermal decomposition of various polymeric materials occur in emergency situations associated with fires, with pulmonotoxicants releasing in the environment. During pyrolysis of polytetrafluoroethylene (Teflon), a highly toxic perfluoroisobutylene is produced.

Intention. To create an experimental animal model of toxic pulmonary edema due to products of thermal decomposition of polytetrafluoroethylene.

Methodology. Polytetrafluoroethylene underwent pyrolysys at 440–750 0С during 6 minutes. Toxic pulmonary edema was modeled on rats via inhalation of pyrolysis products of polytetrafluoroethylene. An amount of polytetrafluoroethylene burned under these conditions with resulting death of 50 % of rats during 1 day was (2.68 ± 0.60) g. The toxic pulmonary edema diagnosis was confirmed histologically and by lung/body ratio.

Results. In the pyrolysis products of polytetrafluoroethylene, highly toxic perfluoroisobutylene was found via gas chromatography with mass spectrometric detection, with relative content of 85.9 %. Such an exposure during 15 min increased (p = 0.01) lung/body ratio in laboratory animals in 3 hours. The toxic pulmonary edema diagnosis was confirmed histologically  (signs of alveolar edema). Animals started to die 7 hours after the pyrolysis products inhalation.

Conclusion. In the study on rats, toxic pulmonary edema was modeled via inhalation of pyrolysis products of polytetrafluoroethylene. This model can be used for searching etiotropic and pathogenetic therapy for poisoning with pulmonotoxicants.

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