Twenty-year trends and exposure assessment of polychlorinated dibenzodioxins and dibenzofurans in human serum from the Seoul citizens.

This study investigated polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in air (n = 108) and human serum (n = 1802) samples collected over 20 years to evaluate the long-term exposure to PCDD/Fs and health effects on the Korean general population. The serum PCDD/F levels were higher in males than in females and were significantly correlated with age, body mass index, and manifestation of diabetes mellitus. From 2000 to 2019, the PCDD/F levels declined by 96% in the air, but only by 36% in the serum, because PCDD/Fs are relatively stable in the human body and are exposed to humans after PCDD/Fs are distributed and migrated in various environmental matrices. The PCDD/F levels in other environmental matrices have also decreased at rates that differed among the matrices due to the different retention times and changes in continuous input of contaminants. As PCDD/Fs migrate from environmental matrices to the human body, the fraction of PCDDs increased whereas that of PCDFs decreased because of their relatively short half-lives. This study provides a concrete evidence that PCDD/F emissions by national regulations can achieve long-term reduction in human exposure. To the best of our knowledge, this is the longest and largest study to evaluate the long-term trends and annual changes of PCDD/Fs in the atmosphere and human serum, simultaneously.