Determination of Potentially Toxic Elements in Quinoa Crops Located in the Huacaybamba–Huanuco-Peru Area

Abstract

Soil contamination by heavy metals is a global environmental problem, which has attracted public attention due to the consumption of various agricultural products. When heavy metals are mentioned, they refer mainly to metals and metalloids that have biological toxicity such as cadmium, lead, mercury and arsenic, which have the capacity to bioaccumulate in the kidneys and liver, causing carcinogenic renal and brain tumors. These elements are mobilized in soils through natural processes such as mineral deposits, groundwater, hot springs, volcanic rocks, and also through anthropogenic activities related to mining activity in the area. Consequently, heavy metal contamination poses a great threat to human health, due to the potential risk of bioaccumulation of these heavy metals through the food chain. Quinoa is a plant grown in the Andean highlands of Peru and Bolivia and is becoming increasingly popular due to its high nutritional value and protein content. In particular, the cultivation of quinoa has grown substantially in recent years, and is in great demand in the national and international markets, due to the fact that the free trade agreement for imports of quinoa in the US does not pay tariffs, thus Peruvian exports could be favored. However, despite the interest that quinoa has generated in terms of its nutritional properties, little is known about the environmental profile of its production and processing. Therefore, the main objective of this study is to determine the presence of some potentially toxic elements (PTE) such as As, Pb, Cd, Zn and Cu that can be found in quinoa production. Currently, there is no information on the contents of these elements in the crops located in Huacaybamba-Huánuco. That is why in the present work we will use a methodology for taking soil samples from the areas, then through instrumental analysis by atomic absorption spectrophotometry, the concentrations of PTE present in the study area will be determined. As a result, according to the quality standard for agricultural soils in Peru and the European standard, it was found that in the case of Arsenic, Copper and Zinc all the concentration data obtained were below the permissible limits, while for Lead, the 46 % of the data obtained exceeded the standard and in the case of Cadmium, 100 % of the data obtained exceeded the environmental quality standard in the soil. Based on this information, the distribution of these elements will be characterized using geochemical maps of the area.