Department of Chemistry, Quaid-i-Azam University, Islamabad, 45320, Pakistan.
Environ Monit Assess. 2019 Oct 17;191(11):650. doi: 10.1007/s10661-019-7829-x.
Fruits are important components of human diet, and their contamination by environmental pollutants is an emerging challenge nowadays. The present study is based on the measurement of selected essential and toxic trace metals including Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Cr, Co, Sr, Li, Ni, Pb, and Cd in commercially available citrus fruits from Pakistan. The samples were digested in HNO and HCLO mixture, and the metal contents were quantified by flame atomic absorption spectrometry. Highest concentration was found for Ca (609.0-3596 mg/kg), followed by relatively higher levels of K (277.6-682.1 mg/kg), Mg (53.65-123.4 mg/kg), Na (1.173-52.14 mg/kg), and Fe (0.236-10.57 mg/kg), while Li, Ni, and Cd showed the lowest contributions in most of the samples. In addition, antioxidant activities such as DPPH radical scavenging assay, hydroxyl radical scavenging activity, ferrous chelating activity, ferric reducing antioxidant power assay, and phosphomolybdenum assay were also evaluated in the fruit samples. Considerably higher antioxidant activities were shown by grapefruit, mandarin, sweet lime, and tangerine. Most of the antioxidant assays were significantly correlated with Na, Mg, Fe, Mn, and Cu levels in the fruits. Human health risk was evaluated in terms of health risk index (HRI), target hazard quotient (THQ), and target cancer risk (TCR) which revealed insignificant health risks; thus, the consumption of these fruits can be considered as safe for human diet.
水果是人类饮食的重要组成部分，而其被环境污染物所污染是当前一个新出现的挑战。本研究基于对巴基斯坦市售柑橘类水果中包括 Na、K、Ca、Mg、Fe、Zn、Cu、Mn、Cr、Co、Sr、Li、Ni、Pb 和 Cd 在内的选定必需和有毒痕量金属的测量。样品在 HNO 和 HCLO 混合物中消解，并用火焰原子吸收光谱法定量金属含量。发现 Ca 的浓度最高（609.0-3596 mg/kg），其次是相对较高的 K（277.6-682.1 mg/kg）、Mg（53.65-123.4 mg/kg）、Na（1.173-52.14 mg/kg）和 Fe（0.236-10.57 mg/kg），而 Li、Ni 和 Cd 在大多数样品中的含量最低。此外，还评估了水果样品中的 DPPH 自由基清除测定、羟基自由基清除活性、亚铁螯合活性、铁还原抗氧化能力测定和磷钼酸盐测定等抗氧化活性。葡萄柚、橘子、甜酸橙和橘子表现出相当高的抗氧化活性。大多数抗氧化测定与水果中的 Na、Mg、Fe、Mn 和 Cu 水平显著相关。根据健康风险指数 (HRI)、目标危害系数 (THQ) 和目标癌症风险 (TCR) 评估了人类健康风险，结果表明健康风险可忽略不计；因此，这些水果的消费可以被认为是安全的人类饮食。
