Determinación de metales pesados en el forraje consumido por el ganado vacuno de la parroquia Bilbao y evaluación de su incidencia en la cadena alimentaria

Abstract

The purpose of this research was to determine the concentration of heavy metals (HM) in the forage consumed by the cattle of the Bilbao parish, province of Tungurahua to evaluate its impact on the food chain. In which was quantified the concentrations of lead, cadmium, mercury, arsenic, and selenium in soil samples, forage, and milk, by the method of atomic absorption spectroscopy with flame and generator of hydrides. The type of sampling used was simple random probability and was carried out in seven points that covered the entire dairy farming area of Bilbao. Parameters analyzed to evaluate the adsorptive capacity of the soil were pH, electrical conductivity, real, apparent density, texture, and organic matter. In addition, the levels of primary macronutrients in the soil and forage, in which sodium and anions were also found. HM were determined at the root level, a physicochemical analysis was performed on the quality of milk, finally, the concentrations of HM, and transfer factors were evaluated for health risks factors. The results obtained were entered into the SPSS software where an ANOVA analysis of variance and TUKEY-B test were also performed. Concentrations of the five metals in the soil samples are below the limit established in the regulations, in the forage, root, and milk samples the concentrations are below the detection limit from the applied method, however, the concentrations obtained from arsenic and selenium in forage and root are below the permissible limit. It is concluded that the three matrices analyzed do not present contamination by heavy metals. Therefore, these do not generate health risks, in addition to the fact that the adsorptive capacity of the soil is acceptable. It’s highly recommended to carry out the quantification of heavy metals with more sensitive methods.