Damana Shibiru, Geletu Abiyot Kelecha, Keru Ibrahim Umer
Department of Chemistry, College of Natural and Computational Science, Mattu University, Mattu, Ethiopia.
Department of Chemistry, College of Natural and Computational Science, Oda Bultum University, Harar, Ethiopia.
Environ Health Insights. 2024 Apr 15;18:11786302241246455. doi: 10.1177/11786302241246455. eCollection 2024.
Khat () is a stimulant plant grown in East Africa and the Arabian Peninsula. Heavy metal pollution has been a global concern due to its acute and chronic health effects and the major route of exposure is the consumption of contaminated foods. In this study, the determination and health risk assessment of heavy metals (Mn, Cu, Zn, Ni, Cr, Cd, and Pb) in khat and its support soil samples was carried out.
Khat and its support soil were analyzed for the levels of 7 toxic heavy metals by Atomic Absorption Spectrophotometer. Samples were randomly collected from 3 districts of khat farming kebeles and digested using mixture of strong acids.
The concentrations (mg/kg) of analytes in soil and khat samples were: Cu (6.78-35.80); Zn (24.30-199.02); Mn (7.59-1855.40); Ni (6.37-64.80); Cr (0.82-169.20); Cd (14.2-38.8), and Pb (ND). Among the analyzed heavy metals in soil, Mn was with the highest concentration, followed by Zn, Cr, Cu, Ni, and Cd while that of Zn was the maximum followed by Cu, Mn, and Cr in khat. The levels of Zn, Cr, and Cd in soil samples from all study sites and detected concentrations of Cr in khat samples exceeded the recommended FAO/WHO levels.
The hazard index (HI) of metals in khat from study areas was less than 1 indicating a less likelihood of non-carcinogenic toxicological health effects. However, the presence of these toxic chemicals in soil and khat indicates product contamination and needs extensive further investigation involving other heavy metals.
巧茶是一种生长在东非和阿拉伯半岛的刺激性植物。由于其对健康的急性和慢性影响，重金属污染已成为全球关注的问题，主要暴露途径是食用受污染的食物。本研究对巧茶及其支撑土壤样本中的重金属（锰、铜、锌、镍、铬、镉和铅）进行了测定和健康风险评估。
采用原子吸收分光光度计分析巧茶及其支撑土壤中7种有毒重金属的含量。从3个巧茶种植社区随机采集样本，并用强酸混合物进行消解。
土壤和巧茶样本中分析物的浓度（mg/kg）为：铜（6.78 - 35.80）；锌（24.30 - 199.02）；锰（7.59 - 1855.40）；镍（6.37 - 64.80）；铬（0.82 - 169.20）；镉（14.2 - 38.8），铅（未检出）。在土壤中分析的重金属中，锰的浓度最高，其次是锌、铬、铜、镍和镉，而在巧茶中锌的含量最高，其次是铜、锰和铬。所有研究地点土壤样本中的锌、铬和镉含量以及巧茶样本中检测到的铬浓度均超过了粮农组织/世界卫生组织推荐的水平。
研究区域巧茶中金属的危害指数（HI）小于1，表明非致癌毒理学健康影响的可能性较小。然而，土壤和巧茶中这些有毒化学物质的存在表明产品受到了污染，需要对其他重金属进行广泛的进一步调查。
