Institute for Chemical and Bioengineering, ETH Zurich , Vladimir-Prelog-Weg 1, CH-8093 Zürich, Switzerland.
Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
Environ Sci Technol. 2017 Sep 19;51(18):10536-10545. doi: 10.1021/acs.est.7b02968. Epub 2017 Sep 6.
We report on two farms in Switzerland heavily contaminated by polychlorinated biphenyls (PCBs) and dioxins (PCDD/Fs), occurring in the first case from diffuse sources and in the second case from PCB-containing wall paint. Extensive measurements of PCBs and PCDD/Fs on site (soil, forage, and paint) and in cattle (blood, fat, and milk) allowed validation of our novel dynamic toxicokinetic model, which includes the transfer of contaminants from the mother cows to their suckling calf and the uptake of soil by grazing cattle. We show that for calves, the mother milk is the main uptake route of contaminants. For both cows and calves, ingestion of contaminated soil, although often overlooked, is an appreciable uptake path. The remediation of the contaminated stable lead to a 2-3 fold reduction of the PCB levels in animals within one year. The transfer of animals to an uncontaminated mountain site during summer proved to be an effective decontamination procedure with up to 50% reduction of the levels within three months. Our study calls for a rapid removal of PCB-containing materials in animal husbandry farms and shows that the diffuse contamination of soils will remain a source for PCBs and PCDD/Fs in our food chain for decades to come.
我们报道了瑞士的两个农场，这些农场受到多氯联苯（PCBs）和二恶英（PCDD/Fs）的严重污染，第一种情况是由弥散源引起的，第二种情况是由含 PCB 的墙漆引起的。对现场（土壤、饲料和油漆）和牛（血液、脂肪和牛奶）中的 PCBs 和 PCDD/Fs 进行了广泛测量，验证了我们新颖的动态毒代动力学模型，该模型包括污染物从母牛转移到其哺乳小牛以及食草牛对土壤的摄取。我们表明，对于小牛来说，母乳是污染物的主要吸收途径。对于母牛和小牛来说，摄入受污染的土壤虽然经常被忽视，但也是一种重要的吸收途径。受污染的畜栏的修复导致动物体内的 PCB 水平在一年内降低了 2-3 倍。在夏季将动物转移到未受污染的山区证明是一种有效的净化程序，可在三个月内将水平降低 50%。我们的研究呼吁在畜牧业农场中迅速清除含 PCB 的材料，并表明未来几十年，土壤的弥散污染仍将是食物链中 PCBs 和 PCDD/Fs 的来源。
