PCDDs/DFs emissions from crematories in Japan

Concentrations of PCDDs and PCDFs in emission gases from 10 crematories wer e measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. F urthermore, emission of PCDDs/DFs from all crematories in Japan is estimate d. The following results are obtained: (1) total concentration of PCDDs/DFs was 2.2-290 ng/N m(3), whose TEQ concentration was 0.0099-6.5 ng TEQ/N m(3 ); (2) total concentration of PCDFs was higher than that of PCDDs; (3) T4CD Fs was the highest in the homologue pattern and 2,3,7,8-T4CDF was the highe st in the isomer pattern; (4) emission of PCDDs/DFs was the largest in the first 20 min of cremation; (5) concentration of PCDDs/DFs was related to th e existence of a secondary combustion chamber and a dust collector, and the ratio of the numbers of main and secondary combustion chambers; (6) total emission of PCDDs/DFs from crematories in Japan was estimated to be 8.9 g T EQ/yr. (C) 2000 Elsevier Science Ltd. All rights reserved.