Analytical, Environmental and Geo-Chemistry laboratory (AMGC), Vrije Universiteit Brussel (University of Brussels), Pleinlaan 2, 1050 Brussels, Belgium; Department of Chemistry, University of Sciences, Hue University, Hue 530000, Vietnam.
Faculty of Chemical & Food Technology, University of Technology and Education, Thu Duc, Ho Chi Minh 700000, Vietnam.
Ecotoxicol Environ Saf. 2021 Apr 1;212:111971. doi: 10.1016/j.ecoenv.2021.111971. Epub 2021 Jan 26.
In this study, an AhR-responsive reporter-gene cell-based bioassay CALUX was used to assess the biological potency of dioxins and dioxin-like PCBs (dl-PCBs) in top soil samples collected from a former airbase (A-So) and remote regions from urban and agricultural areas in Thua Thien Hue, Vietnam. In top soil collected from A-So airbase, Bioanalytical EQuivalent (BEQ) concentrations of up to 2700 pg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) per g dry weight (pg BEQ-TCDD g dw) were assessed. Interestingly, while BEQ values for dl-PCBs were found to be up to 13 pg BEQ-TCDD g dw, the dl-PCB activity was not detected in all the hotspot sample extracts. In contrasts, BEQ values for dioxin like compounds from remote regions were much lower and occasionally below the quantification limits of the method. The BEQ activities obtained in this study have a similar trend to the WHO-TEQ results for the samples collected in the A-So airbase. However, BEQ values were higher than those of TEQ, probably reflecting the presence of additional AhR ligands and/or possible non-additive interactions in the sample mixture. This study confirms that after more than 60 years, a strong residual pollution of PCDD/Fs remains on this former air base following the use and storage of Agent Orange during the Vietnam War, raising a health risk for populations exposed in this area because livestock animals graze there.
在这项研究中，使用了一种 AhR 反应性报告基因细胞生物测定 CALUX 来评估从越南顺化前空军基地（A-So）和远离城市和农业地区采集的表层土壤样本中二恶英和类二恶英多氯联苯（dl-PCBs）的生物效力。在 A-So 空军基地采集的表层土壤中，检测到高达 2700 pg 2,3,7,8-四氯二苯并对二恶英（TCDD）每克干重的生物分析等效（BEQ）浓度（pg BEQ-TCDD g dw）。有趣的是，虽然 dl-PCBs 的 BEQ 值高达 13 pg BEQ-TCDD g dw，但在所有热点样本提取物中均未检测到 dl-PCB 活性。相比之下，来自偏远地区的类似二恶英化合物的 BEQ 值要低得多，偶尔低于该方法的定量限。本研究中获得的 BEQ 活性与在 A-So 空军基地采集的样本的世界卫生组织-毒性当量（WHO-TEQ）结果具有相似的趋势。然而，BEQ 值高于 TEQ 值，这可能反映了样品混合物中存在其他 AhR 配体和/或可能存在非加性相互作用。这项研究证实，在越南战争期间使用和储存橙剂 60 多年后，这个前空军基地仍然存在强烈的 PCDD/F 残留污染，对该地区的暴露人群构成健康风险，因为牲畜在那里放牧。
