Evaluation of a Method for the Quantification of Cadmium, Lead, and Zinc in Craft Beers Manufactured in Quito, Ecuador

The brewing process of craft beer can introduce contamination by heavy metals such as Cd, Pb, and Zn from various sources. Cadmium and lead metals are particularly worrisome because of their harmful effects on human health. This study aimed to evaluate a method for quantifying the levels of Cd, Pb, and Zn in craft beer brands sold in the northern region of the Metropolitan District of Quito, Ecuador, using atomic absorption spectroscopy. For confidentiality, the brands were anonymized as Brands A to I. Standard addition curves were employed for metal quantification, with repeatability assessed via the coefficient of variation (CV%) and accuracy determined by recovery (R%). The Cd content in Brands B-G and I was below the threshold established by the Mercosur Resolution Nº 12/11. Additionally, Brands A and D-H complied with the Ecuadorian INEN 2262 standard for maximum Pb concentration in beer. All samples showed Zn levels substantially below the maximum levels permitted by Ecuadorian regulations. Brands A, B, C, and H exhibited the highest concentrations of Cd and Pb.