An accidental death due to Freon 22 (monochlorodifluoromethane) inhalation in a fishing vessel

Abstract A case of accidental Freon 22 (monochlorodifluoromethane) poisoning in a fishing vessel is reported. Forensic autopsy revealed severe pulmonary edema and congestion (left lung; 576 g, right lung; 740 g). GC–MS analysis clearly showed that the deceased inhaled Freon 22 gas prior to his death. Freon 22 concentration was 169 ± 7.0 μg/ml in the heart blood. The distribution pattern of Freon 22 in tissue samples was similar to that in previously reported cases. The brain had the highest concentration of Freon 22 followed by the spleen, liver, kidney and lung, respectively. Histopathologically, Oil red O staining of the liver showed many small, positive red areas in the cytosol, which have been reported in other cases of Freon 22 poisoning. However, Schmorl staining revealed that most areas of Oil red O positivity were lipofuscin granules. Lipofuscin in the liver, which closely relates to aging and other cell stresses, could have a relevance to Freon 22 exposure, but further experimental studies are needed to confirm it.