Ben Mordechay Evyatar, Mordehay Vered, Tarchitzky Jorge, Chefetz Benny
Department of Soil and Water Sciences, Institute of Environmental Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel.
Department of Soil and Water Sciences, Institute of Environmental Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel.
Sci Total Environ. 2022 May 20;822:153574. doi: 10.1016/j.scitotenv.2022.153574. Epub 2022 Jan 31.
Reclaimed wastewater irrigation, a common agricultural practice in water-scarce regions, chronically exposes the agricultural environment to a wide range of contaminants of emerging concern (CECs) including pharmaceuticals and personal care products. Here we provide new data and insights into the processes governing the translocation of CECs in the irrigation water-soil-plant continuum based on a comprehensive dataset from 445 commercial fields irrigated with reclaimed wastewater. We report on CEC exposures in irrigation water, soils, and edible produce (leafy greens, carrots, potatoes, bananas, tomatoes, avocados, and citrus fruits). Our data show that CEC concentrations in irrigation water and their physiochemical properties (mainly charge and lipophilicity) are the main factors governing their translocation and accumulation in the soil-plant continuum. CECs exhibiting the highest detection frequency in plants (lamotrigine, venlafaxine, and carbamazepine) showed a reduction in their leaf accumulation factor with increasing soil organic matter content. The higher soil organic matter likely reduced the available CEC concentration in the soil solution due to soil-CEC interactions, leading to reduced uptake. Interestingly, the concentration of carbamazepine in the leaves showed a saturation-like trend when plotted against its concentration in the soils. This probably resulted from steady-state conditions when uptake equals in-planta decomposition. Our data indicate that due to continuous reclaimed wastewater irrigation, the soil acts as a sink for CECs. CECs in the soil reservoir can be desorbed into the soil solution during the rainy season and be taken up by rain-fed crops.
再生水灌溉是缺水地区常见的农业做法，长期使农业环境暴露于包括药品和个人护理产品在内的多种新出现的关注污染物（CECs）中。在此，我们基于来自445个使用再生水灌溉的商业田地的综合数据集，提供了关于CECs在灌溉水-土壤-植物连续体中迁移过程的新数据和见解。我们报告了灌溉水、土壤和可食用农产品（绿叶蔬菜、胡萝卜、土豆、香蕉、西红柿、鳄梨和柑橘类水果）中的CEC暴露情况。我们的数据表明，灌溉水中CEC的浓度及其物理化学性质（主要是电荷和亲脂性）是控制其在土壤-植物连续体中迁移和积累的主要因素。在植物中检测频率最高的CECs（拉莫三嗪、文拉法辛和卡马西平）随着土壤有机质含量的增加，其叶片积累系数降低。较高的土壤有机质可能由于土壤-CEC相互作用而降低了土壤溶液中可利用的CEC浓度，导致吸收减少。有趣的是，当将叶片中卡马西平的浓度与其在土壤中的浓度作图时，呈现出类似饱和的趋势。这可能是由于吸收等于植物内分解时的稳态条件所致。我们的数据表明，由于持续的再生水灌溉，土壤充当了CECs的汇。土壤储库中的CECs在雨季可解吸到土壤溶液中，并被雨养作物吸收。
