Sheikhi Mahdieh, Bostani Amir
Soil Science Department, Faculty of Agriculture, Shahed University, Tehran, 15614, Iran.
Soil and Health Research Center, Shahed University, Tehran, 15614, Iran.
Biol Trace Elem Res. 2025 Sep 8. doi: 10.1007/s12011-025-04811-x.
The effect of mixed potable and wastewater (WW) irrigation on leafy vegetables cultivated in southern Tehran, Iran, was investigated in 2022. Eight species-spinach (Spinacia oleracea), scallion (Allium fistulosum), radish (Raphanus sativus), cress (Lepidium sativum), basil (Ocimum basilicum), purslane (Portulaca oleracea), cilantro (Coriandrum sativum), and savory (Satureja hortensis)-were grown in calcareous loamy soil under greenhouse conditions using five irrigation regimes (0%, 25%, 50%, 75%, and 100% WW) applied every 2 days. Soil salinity, DTPA-extractable Co, Cu, Ni, and Zn, plant growth traits, and health risk indices-transfer factor (TF), bioaccumulation factor (BAF), average daily dietary intake (ADD), hazard quotient (HQ), and cancer risk (CR)-were determined for children and adults. Heavy metal (HM) accumulation differed significantly among wastewater levels and plant species (p < 0.05). While low WW levels (≤ 50%) enhanced plant growth parameters, higher application rates sharply increased soil salinity (up to 6.5 dS m⁻1) and DTPA-extractable Co, Cu, Ni, and Zn. Zn and Cu were retained mainly in roots, whereas Ni and Co were more readily translocated to shoots, especially at 50-75% WW. Radish exhibited the highest TF, particularly for Zn and Ni. Children showed 2.8-3.1 times higher ADD and HQ values than adults, indicating greater vulnerability. The CR for Ni exceeded the 10⁻4 threshold, particularly in radish and scallion. BAF values exceeded 1 in all vegetables except radish, following the order Cu > Zn > Ni > Co. These findings suggest that strategic substitution of WW with potable water can sustain yields while limiting HM risks, guiding safe irrigation strategies in semi-arid urban agriculture.
2022年，研究了伊朗德黑兰南部混合饮用和废水灌溉对叶菜类蔬菜的影响。在温室条件下，将菠菜（Spinacia oleracea）、葱（Allium fistulosum）、萝卜（Raphanus sativus）、水芹（Lepidium sativum）、罗勒（Ocimum basilicum）、马齿苋（Portulaca oleracea）、香菜（Coriandrum sativum）和夏香薄荷（Satureja hortensis）这八个品种种植在石灰性壤土中，每2天采用五种灌溉方式（0%、25%、50%、75%和100%废水）进行灌溉。测定了土壤盐分、DTPA可提取的钴、铜、镍和锌、植物生长性状以及儿童和成人的健康风险指数——转移因子（TF）、生物累积因子（BAF）、平均每日膳食摄入量（ADD）、危害商数（HQ）和癌症风险（CR）。重金属（HM）积累在废水水平和植物品种之间存在显著差异（p < 0.05）。虽然低废水水平（≤50%）提高了植物生长参数，但较高的施用量急剧增加了土壤盐分（高达6.5 dS m⁻¹）以及DTPA可提取的钴、铜、镍和锌。锌和铜主要保留在根部，而镍和钴更容易转运到地上部分，尤其是在50 - 75%废水灌溉时。萝卜表现出最高的转移因子，特别是对于锌和镍。儿童的ADD和HQ值比成人高2.8 - 3.1倍，表明儿童更易受影响。镍的癌症风险超过了10⁻⁴阈值，特别是在萝卜和葱中。除萝卜外，所有蔬菜的生物累积因子值均超过1，顺序为铜>锌>镍>钴。这些研究结果表明，用饮用水战略性替代废水可以在限制重金属风险的同时维持产量，为半干旱城市农业中的安全灌溉策略提供指导。
