Evaluation of various soaking agents as a novel tool for heavy metal residues mitigation from spinach

Abstract Heavy metals pollution is a global threat to the environment and ecosystem due to various human and natural activities. Heavy metal intake through vegetables and diet leads to numerous ailments such as nervous disorder, kidney damage tubular growth and bone disease. The present study was conducted to mitigate the residue of heavy metals Hg, Pb, Zn and As in spinach collected from self-grown supervised field by using different washing treatments. Amount of trace metals was measured in fresh and chemically washed spinach samples with the help of Atomic Absorption Spectrophotometer (AAS). Results revealed that highest reduction of mercury, lead, zinc and arsenic residues with 10% citric acid was 23%, 28%, 54% and 22% respectively among the tested solutions. However, tap water treatment also reduced 7%, 7%, 15% and 6, respectively. Among various washing solutions citric acid proved maximum reduction potential followed by Lemon extract, sodium carbonate, reddish extract and hydrogen peroxide respectively. The percent reduction by various solutions ranged from 7 to 23%, 7 to 28%, 15 to 54% and 6 to 22% for elimination of mercury, lead, zinc and arsenic, respectively. More reduction was found in zinc followed lead, mercury and arsenic.

摘要：受各类人类活动与自然活动影响，重金属污染已对全球环境及生态系统构成严重威胁。通过蔬菜与膳食摄入重金属，会引发多种疾病，包括神经功能紊乱、肾损伤、肾小管病变及骨病。本研究旨在通过不同清洗处理方式，降低自种监管农田采集的菠菜中汞（Hg）、铅（Pb）、锌（Zn）及砷（As）的残留量。借助原子吸收分光光度计（Atomic Absorption Spectrophotometer, AAS），对新鲜样本及经化学清洗处理的菠菜样品中的痕量金属含量进行了测定。实验结果显示，在所有受试清洗液中，10%柠檬酸溶液对汞、铅、锌、砷残留的去除率最高，分别可达23%、28%、54%及22%。但自来水清洗处理的去除率也分别达到7%、7%、15%及6%。在各类清洗液中，柠檬酸溶液的重金属去除效果最优，其次依次为柠檬提取物、碳酸钠、红提取物及过氧化氢。各类清洗液对汞、铅、锌、砷的去除率范围分别为7%~23%、7%~28%、15%~54%及6%~22%。整体而言，锌的去除效果最佳，其次依次为铅、汞与砷。