White Jason C, Parrish Zakia D, Isleyen Mehmet, Gent Martin P N, Iannucci-Berger William, Eitzer Brian D, Kelsey Jason W, Mattina Maryjane Incorvia
Department of Soil and Water, Connecticut Agricultural Experiment Station (CAES), 123 Huntington Street, New Haven, CT 06504, USA.
Int J Phytoremediation. 2006;8(1):63-79. doi: 10.1080/15226510500507102.
A series of small and large pot trials were conducted to assess the phytoextraction potential of several plant species for weathered polychlorinated biphenyls (PCBs) in soil (105 microg/g Arochlor 1268). In addition, the effect of citric acid on PCB bioavailability to both plants and earthworms was assessed. Under small pot conditions (one plant, 400 g soil), three cucurbits (Cucurbita pepo ssp pepo [zucchini] and ssp ovifera [nonzucchini summer squash], Cucumis sativus, cucumber) accumulated up to 270 microg PCB/g in the roots and 14 microg/g in the stems, resulting in 0.10% contaminant removal from soil. Periodic 1 mM subsurface amendments of citric acid increased the stem and leaf PCB concentration by 330 and 600%, respectively, and resulted in up to a 65% increase in the total amount of contaminant removed from soil. Although citric acid at 10 mM more than doubled the amount of PCB desorbed in abiotic batch slurries, contaminant accumulation by two earthworm species (Eisenia foetida and Lumbricus terrestris) was unaffected by citric acid at 1 and 10 mM and ranged from 11-15 microg/g. Two large pot trials were conducted in which cucurbits (C. pepo ssp pepo and ssp ovifera, C. sativus) and white lupin (Lupinus albus) were grown in 70 kg of PCB-contaminated soil White lupin was the poorest accumulator of PCBs, with approximately 20 microg/g in the roots and 1 microg/g in the stems. Both C. pepo ssp ovifera (summer squash) and C. sativus (cucumber) accumulated approximately 65-100 microg/g in the roots and 6-10 microg/g in the stems. C. pepo ssp pepo (zucchini) accumulated significantly greater levels of PCB than all other species, with 430 microg/g in the roots and 22 microg/g in the stems. The mechanism by which C. pepo spp pepo extracts and translocates weathered PCBs is unknown, but confirms earlier findings on the phytoextraction of other weathered persistent organic pollutants such as chlordane, p,p'-DDE, and polycyclic aromatic hydrocarbons.
开展了一系列小型和大型盆栽试验,以评估几种植物对土壤中老化多氯联苯(PCBs,含量为105微克/克氯丹1268)的植物提取潜力。此外,还评估了柠檬酸对植物和蚯蚓吸收PCBs生物有效性的影响。在小型盆栽条件下(每盆一株植物,400克土壤),三种葫芦科植物(西葫芦南瓜变种西葫芦和南瓜变种非西葫芦夏季南瓜、黄瓜、黄瓜)根部积累的PCBs高达270微克/克,茎部积累量为14微克/克,土壤中污染物去除率为0.10%。定期在地下添加1毫摩尔的柠檬酸,使茎部和叶片中PCBs浓度分别增加了330%和600%,土壤中污染物去除总量增加了65%。尽管10毫摩尔的柠檬酸使非生物批次泥浆中解吸的PCBs量增加了一倍多,但两种蚯蚓(赤子爱胜蚓和陆正蚓)对污染物的积累不受1毫摩尔和10毫摩尔柠檬酸的影响,积累量在11 - 15微克/克之间。进行了两项大型盆栽试验,将葫芦科植物(西葫芦南瓜变种西葫芦和南瓜变种非西葫芦、黄瓜)和白羽扇豆种植在70千克受PCBs污染的土壤中。白羽扇豆是PCBs积累能力最差的植物,根部约为20微克/克,茎部为1微克/克。西葫芦南瓜变种非西葫芦(夏季南瓜)和黄瓜根部积累量约为65 - 100微克/克,茎部为6 - 10微克/克。西葫芦南瓜变种西葫芦积累的PCBs水平明显高于所有其他物种,根部为430微克/克,茎部为22微克/克。西葫芦南瓜变种西葫芦提取和转运老化PCBs的机制尚不清楚,但证实了早期关于其他老化持久性有机污染物如氯丹、p,p'-滴滴伊和多环芳烃植物提取的研究结果。