Trace elements in Foodstuffs from the Mediterranean Basin-Occurrence, Risk Assessment, Regulations, and Prevention strategies: A review

Trace elements (TEs) are chemical compounds that naturally occur in the earth's crust and in living organisms at low concentrations. Anthropogenic activities can significantly increase the level of TEs in the environment and finally enter the food chain. Toxic TEs like cadmium, lead, arsenic, and mercury have no positive role in a biological system and can cause harmful effects on human health. Ingestion of contaminated food is a typical route of TEs intake by humans. Recent data about the occurrence of TEs in food available in the Mediterranean countries are considered in this review. Analytical methods are also discussed. Furthermore, a discussion of existing international agency regulations will be given. The risk associated with the dietary intake of TEs was estimated by considering consumer exposure and threshold values such as Benchmark dose lower confidence limit and provisional tolerable weekly intake established by the European Food Safety Authority and the Joint FAO/WHO Expert Committee on Food Additives, respectively. Finally, several remediation approaches to minimize TE contamination in foodstuffs were discussed including chemical, biological, biotechnological, and nanotechnological methods. The results of this study proved the occurrence of TEs contamination at high levels in vegetables and fish from some Mediterranean countries. Lead and cadmium are more abundant in foodstuffs than other toxic trace elements. Geographical variations in TE contamination of food crops clearly appear, with a greater risk in developing countries. There is still a need for the regular monitoring of these toxic element levels in food items to ensure consumer protection.

Trace Elements in Breakfast Cereals and Exposure Assessment in Moroccan Population: Case of Lead and Cadmium

The role of breakfast cereals in a balanced diet has been recognized for many years. Such foods should be safe and not contain toxic substances, especially trace elements. Among these elements, lead (Pb) and cadmium (Cd) are two important inorganic food contaminants. In this study, we assessed the contamination levels of breakfast cereal samples available in Morocco with Pb and Cd. For this, a total of sixty-two (n = 62) samples of breakfast cereals purchased in different markets in the country were surveyed for their Pb and Cd contents by using atomic absorption spectrophotometer (GF-AAS) after total mineralization of samples. Results showed that out of 62 total samples, 47 samples (75.8%) were contaminated with Pb concentrations in the range of 0.016-1.057 μg/g. The remaining samples (24.2%) were under the detection limit (LOD) of Pb. In the case of Cd, 41 samples (66.1%) were contaminated with Cd levels that ranged between 0.011 and 0.123 μg/g. In the present study, four samples (6.45%) of breakfast cereals are above the maximum limit (0.2 μg/g) set by the European Commission Regulation No 1881/2006 for Pb in cereals. However, for the Cd, only one sample exceeded the maximum limit set for this element (0.1 μg/g). The levels compare well with those reported worldwide for similar foodstuffs. The estimation of the provisional weekly intakes of the two elements (Pb and Cd) showed that the risks of development of toxicological effects through breakfast cereals are very low. However, it is important that the long-term exposure to these elements be kept to minimum. This is the first study on the co-occurrence of the two trace elements (Pb and Cd) in breakfast cereal samples commercialized in Morocco.