PCDD/F Emission from Pharmaceutical Industries

The emission levels and profiles of unintentionally formed polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) were comprehensively investigated in flue gases released from 16 regenerative thermal oxidizers (RTOs) belonging to 8 pharmaceutical industries (PIs) in China The PCDD/F total concentrations and TEQ values with great variation, ranged from 0.148-9.051 ng m(3) and 0.008-0.255 ng I-TEQ m(3), respectively. Emission levels of most RTOs were lower than the emission standard of China (0.1 ng I-TEQ m(3)), yet two were above 0.25 ng I-TEQ m(3). The PCDD/F concentrations in flue gases were in the order of HWIs > MSWIs > PIs. OCDD was identified to be the dominant congener in most RTOs, accounting for 21-71 wt%. In addition, 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF and 1,2,3,4,7,8-HxCDF were effective TEQ indicators, especially for 2,3,4,7,8-PeCDF with a Pearson correlation coefficient of 0.995. The estimated annual emission amount (AE) of PCDD/Fs for PIs in this study was in the range of 0.435-11.016 mg I-TEQ year with an average of 2.65 mg I-TEQ year(-1). It was estimated that 19.96 g I-TEQ of PCDD/Fs were emitted from Chinese PIs to atmosphere in 2017. This is the first comprehensive investigation on the unintentional emissions of PCDD/Fs from PIs in China.