Center for Environmental Systems, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, USA.
Chemosphere. 2012 Mar;86(10):1001-7. doi: 10.1016/j.chemosphere.2011.11.036. Epub 2011 Dec 10.
This study investigates the dissolution, sorption, leachability, and plant uptake of tungsten and alloying metals from canister round munitions in the presence of model, well characterized soils. The source of tungsten was canister round munitions, composed mainly of tungsten (95%) with iron and nickel making up the remaining fraction. Three soils were chosen for the lysimeter studies while four model soils were selected for the adsorption studies. Lysimeter soils were representatives of the typical range of soils across the continental USA; muck-peat, clay-loamy and sandy-quartzose soil. Adsorption equilibrium data on the four model soils were modeled with Langmuir and linear isotherms and the model parameters were obtained. The adsorption affinity of soils for tungsten follows the order: Pahokee peat>kaolinite>montmorillonite>illite. A canister round munition dissolution study was also performed. After 24 d, the measured dissolved concentrations were: 61.97, 3.56, 15.83 mg L(-1) for tungsten, iron and nickel, respectively. Lysimeter transport studies show muck peat and sandy quartzose soils having higher tungsten concentration, up to 150 mg kg(-1) in the upper layers of the lysimeters and a sharp decline with depth suggesting strong retardation processes along the soil profile. The concentrations of tungsten, iron and nickel in soil lysimeter effluents were very low in terms of posing any environmental concern; although no regulatory limits have been established for tungsten in natural waters. The substantial uptake of tungsten and nickel by ryegrass after 120 d of exposure to soils containing canister round munition suggests the possibility of tungsten and nickel entering the food chain.
本研究调查了在模拟、特征良好的土壤存在的情况下，来自弹药罐圆形弹药的钨和合金金属的溶解、吸附、浸出和植物吸收。钨的来源是弹药罐圆形弹药，主要由钨（95%）组成，其余部分由铁和镍组成。选择了三种土壤进行淋溶研究，同时选择了四种模型土壤进行吸附研究。淋溶土壤是代表美国大陆典型土壤范围的土壤；泥煤-泥炭、粘壤土和砂质石英砂土壤。四种模型土壤的吸附平衡数据用 Langmuir 和线性等温线进行了拟合，并获得了模型参数。土壤对钨的吸附亲和力顺序为：Pahokee 泥炭>高岭石>蒙脱石>伊利石。还进行了弹药罐圆形弹药的溶解研究。24 天后，测量的溶解浓度分别为：钨、铁和镍的浓度分别为 61.97、3.56 和 15.83 mg/L。淋溶传输研究表明，泥煤和砂质石英土壤具有较高的钨浓度，在淋溶器上层高达 150 mg/kg，随着深度的增加浓度急剧下降，表明土壤剖面中存在强烈的阻滞过程。就对环境构成任何担忧而言，土壤淋溶器流出物中钨、铁和镍的浓度非常低；尽管天然水中尚未为钨制定任何监管限值。在接触含有弹药罐圆形弹药的土壤 120 天后，黑麦草对钨和镍的大量吸收表明钨和镍有可能进入食物链。
