Evaluation of content and estimation of daily intake of cadmium and lead in several varieties of potatoes (Solanum tuberosum L.) cultivated in the Canary Islands (Spain)

Micro solid phase extraction of lead and cadmium using functionalized nanodiamonds@CuAl2O4@HKUST-1 nanocomposite for FAAS analysis in food and water samples

This study focuses on the development and application of a novel nanocomposite (functionalized nanodiamonds@CuAl2O4@HKUST-1)-based µ-SPE method for the sensitive and selective extraction of Pb and Cd from food and water samples. The technique offers high sensitivity and selectivity, allowing accurate measurement of these metals at trace levels. The detection limit is 0.031 µg kg-1 for Cd and 0.052 µg kg-1 for Pb, with a relative standard deviation of 1.7 % for Cd and 4.8 % for Pb. The method was successfully applied to real samples and efficiently quantified Pb and Cd in food and natural water samples. The highest concentrations were found in red lentils (0.274 µg kg-1 Pb) and fresh mint (0.197 µg kg-1Cd), but still below recommended limits set by FAO/WHO (300 µg kg-1 for Pb and 200 µg kg-1 for Cd). It promises to ensure food safety, monitor environmental contamination, and informs regulatory decisions to protect public health.

Heavy metal contamination and health risk evaluation of chestnut (Castanea sativa Miller) consumed in Turkey

This study was performed to determine heavy metals and metalloids in twenty-eight chestnut (Castanea sativa Miller) samples consumed in Turkey by inductively coupled plasma optical emission spectrometry and evaluate health risks for humans through the consumption of chestnut samples. The concentrations of Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni and Zn analyzed in chestnut samples varied from 537 to 635, 608 to 5333, 347 to 972, 207 to 8619, 12,739 to 86,310, 278 to 7549, 8676 to 67,622, 1068 to 18,661 and 3625 to 12,876 µg/kg (dry weight), respectively. The concentrations of Cd and Pb were above the maximum limits determined by the Turkish Food Codex. Healthy risks caused by the heavy metals in the consumed chestnut samples were evaluated by estimating the average daily intake of metal, health risk index (HRI), and total HRI. These results revealed that there is no possible health risk to consumers due to the intake of chestnut samples studied under the current consumption rate.

Heavy Metals in Unprocessed or Minimally Processed Foods Consumed by Humans Worldwide: A Scoping Review

Heavy metals (HM) can be accumulated along the food chain; their presence in food is a global concern for human health because some of them are toxic even at low concentrations. Unprocessed or minimally processed foods are good sources of different nutrients, so their safety and quality composition should be guaranteed in the most natural form that is obtained for human consumption. The objective of this scoping review (ScR) is to summarize the existing evidence about the presence of HM content (arsenic (As), lead (Pb), cadmium (Cd), mercury (Hg), methylmercury (MeHg), and aluminum (Al)) in unprocessed or minimally processed foods for human consumption worldwide during the period of 2011–2020. As a second objective, we identified reported HM values in food with respect to Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) International Food Standards for Maximum Limits (MLs) for contaminants in food. This ScR was conducted in accordance with the Joanna Briggs Institute (JBI) methodology and PRISMA Extension for Scoping Reviews (PRISMA-ScR); advance searches were performed in PubMed, ScienceDirect and FAO AGRIS (Agricultural Science and Technology Information) databases by two reviewers who independently performed literature searches with specific eligibility criteria. We classified individual foods in food groups and subgroups according to the Global Individual Information Food Consumption Data Tool (FAO/WHO GIFT). We homologated all the reported HM units to parts per million (ppm) to determine the weighted mean HM concentration per country and food group/subgroup of the articles included. Then, we compared HM concentration findings with FAO/WHO MLs. Finally, we used a Geographic Information System (GIS) to present our findings. Using our search strategy, we included 152 articles. Asia was the continent with the highest number of publications (n = 79, 51.3%), with China being the country with the largest number of studies (n = 34). Fish and shellfish (n = 58), followed by vegetables (n = 39) and cereals (n = 38), were the food groups studied the most. Fish (n = 42), rice (n = 33), and leafy (n = 28) and fruiting vegetables (n = 29) were the most studied food subgroups. With respect to the HM of interest, Cd was the most analyzed, followed by Pb, As, Hg and Al. Finally, we found that many of the HM concentrations reported exceeded the FAO/OMS MLs established for Cd, Pb and As globally in all food groups, mainly in vegetables, followed by the roots and tubers, and cereals food groups. Our study highlights the presence of HM in the most natural forms of food around the world, in concentrations that, in fact, exceed the MLs, which affects food safety and could represent a human health risk. In countries with regulations on these topics, a monitoring system is recommended to evaluate and monitor compliance with national standards. For countries without a regulation system, it is recommended to adopt international guidelines, such as those of FAO, and implement a monitoring system that supervises national compliance. In both cases, the information must be disseminated to the population to create social awareness. This is especially important to protect the population from the consumption of internal production and for the international markets of the globalized world.

Toxic (Al, Cd, and Pb) and trace metal (B, Ba, Cu, Fe, Mn, Sr, and Zn) levels in tissues of slaughtered steers: risk assessment for the consumers

The levels of toxic metals (Al, Cd, Pb) and trace metals (B, Ba, Cu, Fe, Mn, Sr, Zn) were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) in the muscle (sirloin and chuck) and liver from a total of 180 samples of steers (less than 2 years old) (Bos taurus) of foreign and local origin slaughtered on the island of La Palma (Canary Islands, Spain). As regards toxic metals, Al was the metal with the highest contents in both tissues of the foreign steers (3.75 mg/kg in the muscle and 55.3 mg/kg in the liver) and the local steers (5.60 mg/kg in the muscle and 8.65 mg/kg in the liver). In conclusion, the present study confirmed that beef is a source of trace elements, mainly Fe and Zn. In addition, the consumption of this type of beef did not show significant intakes of toxic metals (Al, Cd, and Pb) and, therefore, the consumption of the steer muscle and liver does not pose a toxicological risk for Spanish consumers.

Bioaccumulation of cadmium in potato tuber grown on naturally high levels cadmium soils in Jamaica

Jamaican soils have been reported to have naturally high level of cadmium (Cd), and its bioaccumulation in edible crops is of great concern for farmers, stakeholders, and public health authorities. The aim of this study was to determine the levels of Cd in soils in Jamaica and its bioaccumulation in potato tubers, and to determine the dominant soil factors influencing this bioaccumulation in potato. In addition, other soil factors were investigated such pH, electric conductivity (EC), cation exchange capacity (CEC), texture, organic matter content (OMC), and soil zinc (Zn) concentration. The soils' pH and Zn concentration were found to be the dominant factors influencing Cd accumulation in potato tubers, and this was confirmed by using a step-wise multiple regression analysis with the soil factors and tuber Cd (P < 0.05). With soil Cd ranging between 0.05 and 62.3 mg kg^-1 and tuber Cd ranging between 0.01 and 0.22 mg kg^-1 fresh weight, the bioaccumulation factor (BCF) of Cd in potato tuber gave a precise assessment of the influence of soil variables on Cd accumulation in potato tuber. The Cd concentration in potato tubers was found 50% higher than that recommended by the World Health Organization (WHO) regulation for potatoes (0.05 mg kg^-1 fresh weight), and therefore, this should raise real concerns about the human health risk in Jamaica.

A Limited Survey of Metal Content in Blue Jack Mackerel ( Trachurus picturatus) Obtained from Markets in the Canary Islands

The levels of 20 metals (aluminum, boron, barium, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, magnesium, manganese, molybdenum, sodium, nickel, lead, strontium, vanadium, and zinc) were analyzed in muscle and liver tissue of Trachurus picturatus marketed in the Canary Islands (Spain) by using inductively coupled plasma optical emission spectrometry. In the liver samples, the mean concentrations in milligrams per kilogram wet weight (wt) of Al (14.7), B (0.99), Ba (1.64), Ca (314), Cd (2.52), Co (0.15), Cu (4.07), Fe (106), Li (3.89), Mn (0.85), Mo (0.16), Na (1510), Ni (0.51), Pb (0.36), Sr (3.54), V (0.78), and Zn (23.13) were higher than those detected in the muscle samples in milligrams per killogram wet wt, which were as follows: Al (8.76), B (0.07), Ba (0.30), Ca (210), Cd (0.01), Co (0.01), Cu (1.51 ), Fe (7.33), Li (1.08), Mn (0.12), Mo (0.01), Na (697), Ni (0.11), Pb (0.04), Sr (1.45), V (0.01), and Zn (4.69). The mean concentrations of Cr, K, and Mg (0.14, 1,904, and 243 mg/kg wet wt, respectively) were higher in muscle than in liver (0.05, 1,333 and 236 mg/kg wet wt, respectively). The mean concentrations of Cd and Pb (0.01 and 0.04 mg/kg wet wt) in muscle did not exceed the maximum limits established by a European Commission regulation (0.1 mg of Cd/kg and 0.3 mg of Pb/kg, respectively). Considering a mean daily consumption of fish muscle for the adult population of 31.9 g/day published in the report on food consumption by the Spanish Ministry of Agriculture and Fisheries, Food and Environment, Mg made the highest contributions to the intake (2.58% for adult women of 60 kg and 2.22% for men of 70 kg), and the estimated intakes of Al (0.35 to 0.46 mg/day), Cd (0.55 to 0.74 mg/day) and Pb (1.66 to 5.53 mg/day) were below the respective established tolerable intakes. In conclusion, the results of this study show that the consumption of muscle from this benthopelagic species can be considered safe in terms of maximum legal limits, while consumption of liver is discouraged as a major source of exposure to toxic metals, such as Al, Cd, and Pb.

Metals in edible seaweed

The concentration levels of 20 metals were analyzed by ICP-OES in edible seaweed (Chondrus, Eisenia, Gelidium, Himanthalia, Laminaria, Palmaria, Porphyra, Undaria), from two origins (Asia vs EU) according to their cultivation practices (conventional vs organic). Red seaweed showed higher concentrations of trace and toxic elements. Porphyra may be used as a potential bioindicator for metals. Significant differences were found between the Asian vs European mean contents. The mean Cd level from the conventional cultivation (0.28 mg/kg) was two points higher than the organic cultivation (0.13 mg/kg). A daily consumption of seaweed (4 g/day) contributes to the dietary intake of metals, mainly Mg and Cr. The average intakes of Al, Cd and Pb were 0.064, 0.001 and 0.0003 mg/day, respectively. Based on obtained results, this study suggests that exposure to the toxic metals analyzed (Al, Cd and Pb) through seaweed consumption does not raise serious health concerns, but other toxic metals should be monitored.

Content of Cadmium and Lead in Vegetables and Fruits Grown in the Campania Region of Italy

Illegal practices of waste combustion and their burial in some land devoted to agricultural crops caused a severe economic crisis of the agriculture and food sector in the Campania region of Italy. To assess the levels of contamination by lead and cadmium, the only metals subject to European Union legislation, a system of monitoring of plant foods in the whole territory of the region has been promoted, with the goal of certifying productions and consumer protection. In fact, products that comply with European Union standards are assigned a Quick Response Code, which guarantees the traceability of the product (manufacturer and location). The code also ensures the safety of the product, as it allows the consumer to see the results of the analysis performed on the specific chain of production. The content of lead and cadmium was determined in 750 vegetable samples by using the atomic absorption spectrophotometry after microwave mineralization. These levels were below the maximum limits in all but three samples; two samples of tomatoes exceeded the maximum level of cadmium, and one sample of valerian contained an excess of lead.