Adjei-Mensah Rebecca, Ofori Hayford, Tortoe Charles, Torgbor Johnson Paa-Nii, Aryee David, Kofi Frimpong Samuel
Ghana Standards Authority, Box MB 245, Accra, Ghana.
Council for Scientific and Industrial Research- Food Research Institute, Box M 20, Accra, Ghana.
Toxicol Rep. 2021 Nov 5;8:1830-1838. doi: 10.1016/j.toxrep.2021.11.001. eCollection 2021.
Unregulated small-scale mining activities, by young untrained men using some poisonous chemicals, occur in several agricultural forest belts in Ghana. These activities contaminate water bodies in these areas, which happen to be the main farming sites where food crops are intensively cultivated. The presence of these heavy metal contaminants in popular food staples is therefore worrying because of its adverse health implications. Previous studies have shown that processing is able to decrease the concentrations of heavy metals in foods. This study investigated the effectiveness of home processing methods (boiling, frying and roasting) in significantly reducing the levels of heavy metal contaminants in food crops grown in and around two main mining centers in Ghana. The heavy metals contaminants analyzed for, were Arsenic (As), Cadmium, (Cd), lead (Pb), Manganese (Mn), and Mercury (Hg), determined using atomic absorption spectrometry (AAS) and inductively-coupled plasma mass spectrometry (ICP-MS). From the data, the average daily intakes of the heavy metals and the associated long-term health risks to consumers were assessed. Unprocessed samples from Akwatia had higher levels of contaminants than those from Obuasi. Levels of Mn, Pb and As recorded in all unprocessed samples were higher compared to WHO permissible limits in foods. The levels showed a decreasing trend in the processed samples; with the lowest As and Pb content recorded after frying and boiling. The study showed that roasting allowed for the least reduction in the heavy metal contaminations in the four food crops. The levels of Cd in both processed and unprocessed samples were within safe WHO specifications. Except for Pb in unprocessed cassava, boiled cassava and unprocessed plantain and Hg (unprocessed yam and roasted yam), the hazard indices of all metals in all food crops were less than one and posed no risk to consumers. The study therefore reveals that the normal home processing methods are able to reduce the levels of heavy metal contaminants found in cassava, cocoyam, plantain and yam considerably.
在加纳，未经培训的年轻人使用一些有毒化学物质进行无监管的小规模采矿活动，这些活动出现在该国的几个农业森林带。这些活动污染了这些地区的水体，而这些地区恰好是集约化种植粮食作物的主要农作地点。因此，常见主食中这些重金属污染物的存在令人担忧，因为其对健康有不利影响。先前的研究表明，加工能够降低食品中的重金属浓度。本研究调查了家庭加工方法（煮、煎和烤）在显著降低加纳两个主要采矿中心及其周边种植的粮食作物中重金属污染物水平方面的有效性。所分析的重金属污染物为砷（As）、镉（Cd）、铅（Pb）、锰（Mn）和汞（Hg），使用原子吸收光谱法（AAS）和电感耦合等离子体质谱法（ICP-MS）进行测定。根据数据，评估了重金属的平均每日摄入量以及对消费者的相关长期健康风险。阿夸蒂亚的未加工样品中的污染物水平高于奥布阿西的样品。与世界卫生组织规定的食品允许限量相比，所有未加工样品中记录的锰、铅和砷的水平更高。加工后的样品中这些水平呈下降趋势；煎和煮后记录的砷和铅含量最低。研究表明，烤对四种粮食作物中重金属污染的降低作用最小。加工和未加工样品中的镉水平均在世界卫生组织的安全规格范围内。除了未加工木薯、煮木薯、未加工大蕉中的铅以及未加工山药和烤山药中的汞外，所有粮食作物中所有金属的危害指数均小于1，对消费者没有风险。因此，该研究表明，正常的家庭加工方法能够大幅降低木薯、芋、大蕉和山药中发现的重金属污染物水平。
