Quantitative risk assessment of occupational exposure to PCDD/Fs in the waste incineration industry / 中华劳动卫生职业病杂志

Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.

Dioxins levels in human blood after implementation of measures against dioxin exposure in Japan

BACKGROUND@#Over the past few decades, the Japanese Ministry of the Environment has been biomonitoring dioxins in the general Japanese population and, in response to public concerns, has taken measures to reduce dioxin exposure. The objectives of this study were to assess the current dioxin dietary intake and corresponding body burden in the Japanese and compare Japanese dioxin data from 2011 to 2016 and 2002-2010 surveys. We also examined the relationship between blood dioxins and health parameters/clinical biomarkers.@*METHODS@#From 2011 to 2016, cross-sectional dioxin surveys were conducted on 490 Japanese (242 males and 248 females, aged 49.9 ± 7.6 years) from 15 Japanese prefectures. Blood (n = 490) and food samples (n = 90) were measured for 29 dioxin congeners including polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) using gas chromatography coupled with high-resolution mass spectrometry. Using the 2006 World Health Organization toxic equivalence factors, the toxic equivalents (TEQs) were calculated. Clinical biomarkers and anthropometric parameters were also measured and information on lifestyle behaviours collected. Data imputations were applied to account for blood dioxins below the detection limit.@*RESULTS@#The median (95% confidence interval or CI) blood levels and dioxin dietary intake was respectively 9.4 (8.8-9.9) pg TEQ/g lipid and 0.3 (0.2-0.4) pg TEQ/kg body weight/day. The median blood dioxin level in the 2011-2016 survey was found to have decreased by 41.3% compared to the 2002-2010 surveys. Participants who were older were found to be more likely to have higher dioxin levels. Blood dioxins were also significantly associated with body mass index, triglycerides, docosahexaenoic acid, eicosapentaenoic acid, and dihomo-gamma-linoleic acid levels in blood. Furthermore, associations between blood dioxin and dietary dioxin intake were evident in the unadjusted models. However, after adjusting for confounders, blood dioxins were not found to be associated with dietary dioxin intake.@*CONCLUSIONS@#Blood dioxin levels declined over the past decade. This study showed that the measures and actions undertaken in Japan have possibly contributed to these reductions in the body burden of dioxins in the Japanese population.

Determination of Dioxin-like Compounds in Soil byAccelerated Solvent Extraction-Silica Gel Column Cleanup-BasicAlumina Column Separation Coupled with Gas Chromatography-Triple Quadrupole Mass Spectrometry / 分析化学

A method for determination of PCDD/Fs, PCBs and PCNs in soil sample was developed by using accelerated solvent extraction (ASE)-silica gel column cleanup-basic alumina column separation coupled with GC-MS/MS.The sample was extracted by ASE with Hexane-methylene chloride (Hex-DCM, 50∶50, V/V) at 120℃.The basic alumina column was used to separate PCDD/Fs, PCBs and PCNs.The extracts were eluted with Hex-DCM (95∶5, V/V) to obtain PCBs and PCNs, followed by Hex-DCM (50∶50, V/V) to obtain PCDD/Fs.The limits of detection (LOD) were in the range of 0.04-0.25 μg/L, 0.10-0.20 μg/L and 0.01-0.05 μg/L for PCDD/Fs, PCBs, PCNs, respectively.The relative standard deviations (RSDs) of average relative response factors (RRF) were below 13%.The recoveries of 13C-labeled internal standards of the three classes of analytes were 50%-95%, 51%-103% and 49%-74%, respectively.Concentrations of ∑PCDD/Fs, ∑PCBs and ∑PCNs in soil samples were 16.1-1148 pg/g, 6.6-152.6 pg/g and 10.9-99.5 pg/g, respectively.The results were consistent with that of high resolution mass spectrometer.

Determination of Polychlorinated Dibenzo-p-dioxins/Dibenzofurans, Dioxin Like Polychlorinated Biphenyls, Brominated Flame Retardants and Polybrominated Dibenzo-p-dioxins/Dibenzofurans in Flue Gas from Stationary Source / 分析化学

A method for simultaneous determination of PCDDs, dl-PCBs, BFRs and PBDD/Fs in flue gas from stationary source was developed. The sample was extracted by Soxhlet apparatus with toluene, and followed by purification through sulfuric acid partition and multi-layer silica gel column separation. The target compounds were then all separated by passing through the active carbon-dispersed silica gel column and reversal eluting. Gas chromatography coupled with a thermostable capillary column ( short length, thin stationary phase film) was operated at pulse injection mode. High resolution mass spectrometry set at low-electron-energy ionization was used for quantification. The high- and low-brominated compounds were determined simultaneously. The detection limits of this method were 0. 081-1. 2 pg for PCDD/Fs, 0. 10-0. 32 pg for dl-PCBs, 0. 14-12 pg for PBDEs, 0. 26-16 pg for new BFRs, 0. 44-3. 6 pg for tetra- to hepta-BDD/Fs and 8. 2-12 pg for OBDD/F. Recoveries ( RSDs) in spiked flue gas samples were 88%-115%(2. 9%-6. 1%) for PCDD/Fs, 84%-118% (3. 2%-10%) for dl-PCBs, 71%-135% (2. 1%-18%) for PBDEs, 71%-114% (2. 9%-7. 4%) for new BFRs, 83%-127% (5. 2%-10%) for tetra-to hepta-BDD/Fs and 52%-149% ( 23%-24%) for OBDD/F. All quality control data fell within the acceptable range specified in analysis standards for flue gas.