Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China.
Environ Sci Pollut Res Int. 2018 Jan;25(1):12-17. doi: 10.1007/s11356-016-7724-8. Epub 2016 Oct 3.
Hydroxylated polychlorinated biphenyls (OH-PCBs) have been found in the environment with high toxicity. Recently, methoxylated polychlorinated biphenyls (MeO-PCBs) were identified as new pollutants and detected in sewage sludge. This study presents a detailed investigation on the uptake, translocation, and metabolism of OH-PCBs and MeO-PCBs in typical crops including maize, wheat, and rice. The interconversion between OH-PCBs and MeO-PCBs were observed. Demethylation of MeO-PCBs was favored over methylation of OH-PCBs. The metabolites were mainly generated in the roots and then translocated to the shoots. Analog-specific differences showed that the accumulation amounts of MeO-PCBs were higher than those of OH-PCBs in the crops. The translocation abilities followed this order: 3'-OH-CB-65 > 4'-OH-CB-101 > 3'-MeO-CB-65 > 4'-MeO-CB-101. The conversion rates were generally higher for 4'-OH-CB-101 than 3'-OH-CB-65 and higher for 4'-MeO-CB-101 than 3'-MeO-CB-65. Interspecies variability among the crops was also observed. The amounts of metabolites and acropetal translocation inside the plants were the greatest for maize. However, the concentration of compounds normalized by the mass of corresponding plant tissue was highest in wheat. These findings provide valuable information for a better understanding of the phytoaccumulation and phytotransformation of OH-PCBs and MeO-PCBs.
羟基多氯联苯 (OH-PCBs) 在环境中被发现具有高毒性。最近，甲氧基多氯联苯 (MeO-PCBs) 被确定为新的污染物，并在污水污泥中被检测到。本研究详细调查了 OH-PCBs 和 MeO-PCBs 在典型作物（包括玉米、小麦和水稻）中的吸收、迁移和代谢。观察到 OH-PCBs 和 MeO-PCBs 之间的互变。MeO-PCBs 的脱甲基化比 OH-PCBs 的甲基化更有利。代谢物主要在根部生成，然后迁移到地上部分。特异性差异表明，MeO-PCBs 在作物中的积累量高于 OH-PCBs。迁移能力的顺序为：3'-OH-CB-65 > 4'-OH-CB-101 > 3'-MeO-CB-65 > 4'-MeO-CB-101。4'-OH-CB-101 的转化率通常高于 3'-OH-CB-65，而 4'-MeO-CB-101 的转化率则高于 3'-MeO-CB-65。不同作物之间也存在种间变异性。玉米体内代谢物的数量和向地上部分的迁移最大，而小麦中相应植物组织质量归一化的化合物浓度最高。这些发现为更好地理解 OH-PCBs 和 MeO-PCBs 的植物积累和植物转化提供了有价值的信息。
