Exposure Assessment of PCDD/Fs and Monitoring of Health Effects on Workers and Residents near the Waste Incinerators in Korea

Abstract

Objectives: In this study, the exposure status of the hazardous suvstances from incinerators, such as polychlorinated dibenzo-p-dioxins(PCDDs) and polychlornated dibenzofurans(PCDFs) were stuided, and the relationship between the pxposure of these hazardous substances and their health effects on the workers and residents near municipal solid waste(MSW) incinerators and an industrial incinerator investigated,

Methods: Between July 2001 and June 2002, 13 workers at two MSW incinerators, 16 residents tram the area around the two MSW incinerators, 6 residents from the control area, and further 10 residentsn near an industrial incinerator, estimated to emit higher levels of hazardous substances, were interviewed. Information, including sociodemographic information, personal habits, and work history, detailed gynecologic and other medical history were collected through interviews. Blood samples were also collected from 45 subjects, and analyzed for PCOD/DFs, by high resolution gas chromatography-high resolution mass spectrometry, using the US EPA 1613 method. In addition to the questionnaire survey, urinary concentrations of 8-hvdroxvdeoxvauanosine (8-OH-dG) and malondialdehyde (MDA) were measured as oxidative injury biomarkers. The urinary concentrations of 8-OH-dG were determined by in vitro ELISA, and the MDA by HPLC, using an adduct with thiobarbituric acid.

Results : The PCDD/DFs concentrations in the residents near the industrial incinerator were higher than those in the controls, workers and residents near the MSW incinerators. The average TEQ(Toxic Equivalencies) concentrations of the PCDD/DFs in residents near the industrial incinerator were 53.4pg I-TEQs/g lipod. The estimated daily intakes were within the tolerable daily intake range(1-4 pg I-TEQ/Kg bw/day) suggested by WHO (1997) in only 30% to the people near the industrial incinerator. Animal studies have already shown the even a low body burden of PCDD/DFs, such as 10ng TEQ/kg bw, can cause oxdative damage in aboratory animals. Our study also showed that the same body burden of PCDD/DFs can cause oxidative damage to humans.

Conclusions : The exposures to PCDD/DFs and the oxidative stress of residents near the industrial incinerator, were higher than those in the controls, workers and residents near the MSW incinerators, Proper protection strategies against these hazardous chemicals are needed. Because a lower body burden of PCDD/Fs, such as 10ng TEQ/kg bw, can cause oxidative damage, the tolerable daily intake range should be restrictedly limited to 1pg I-TEQ/kg bw/day.