Occurrence of Aflatoxin M1 in Milk and Dairy Products Traded in São Paulo, Brazil: An Update

Abstract

The aim of this study was to conduct an up-to-date investigation on the occurrence levels of aflatoxin M1 (AFM1) in samples of raw milk (n = 40), pasteurized milk (n = 44), ultra-high temperature (UHT) milk (n = 27), Minas cheese (n = 57), and yogurt (n = 44) traded in São Paulo state, Brazil. AFM1 was extracted from fluid milks and dairy products using immunoaffinity columns and determined by high performance liquid chromatography. AFM1 was detected at the mean level of 0.080 ± 0.071 µg/L or kg in 72 samples (34.0%) evaluated in the study (n = 212). Detectable levels of AFM1 were observed in five samples of raw milk (12.5%), 16 samples of pasteurized milk (36.4%), 13 samples of UHT milk (48.1%), 27 samples of cheese (47.4%), and 11 samples of yogurt (25.0%), although none of them had concentrations above the maximum permitted levels (MPL) for AFM1 adopted in Brazil. However, 11.7% (n = 13) of samples of raw, pasteurized, and UHT milks would have AFM1 concentrations above the MPL of 0.05 μg/L adopted in the EU. The maximum level was detected in one cheese sample containing 0.695 µg/kg. Although none of the samples exceeded the Brazilian MPL, the high frequencies of AFM1 in Brazilian milk products warrant concern about their contribution to the human exposure to aflatoxins. Because aflatoxins are among the most potent carcinogens known, the results of this trial stress the need for stringent measures in the milk production system to avoid AFM1 in milk and derived products.

Incidence and Levels of Aflatoxin M1 in Artisanal and Manufactured Cheese in Pernambuco State, Brazil

“…Reports suggest that AFM 1 levels may be higher in hard cheese compared to soft cheese, due the higher amount of the milk proteins, mainly casein, to which AFM 1 has a greater binding affinity [ 19 ]. A study in Brazil evaluated the incidence and levels of AFM 1 in a range of milk and milk-derived products, containing several cheese samples ( n = 57) [ 17 ]. The study found that of the analyzed products, except a high occurrence rate, only one cheese samples represented AFM 1 at a level of 0.695 µg/kg [ 17 ].…”

“…A study in Brazil evaluated the incidence and levels of AFM 1 in a range of milk and milk-derived products, containing several cheese samples ( n = 57) [ 17 ]. The study found that of the analyzed products, except a high occurrence rate, only one cheese samples represented AFM 1 at a level of 0.695 µg/kg [ 17 ]. Moreover, HPLC coupled with fluorescence-detector-based analyses of cheeses ( n = 58), incorporating Minas frescal light, Minas frescal, Minas standard, and other type of cheese, found that 67.24% of the cheeses were contaminated with AFM 1 (0.01–0.304 µg/kg), as given in Table 2 [ 28 ].…”

“…Given the potential harm of AFM 1 , Brazil has adopted regulatory limits for this mycotoxin, with maximum permissible limits (MPL) of 0.5 µg/L for fluid milk and 2.5 µg/kg for cheese [ 15 ]. The occurrence and levels of AFM 1 in milk products have been monitored [ 14 ] using several analytical methods, comprising the popular enzyme-linked immunosorbent assay (ELISA) [ 16 ], high-performance liquid chromatography (HPLC) alone [ 17 ], and HPLC combined with tandem mass spectrometry (MS/MS) [ 18 ]. In this context, monitoring AFM 1 concentrations in milk and its derived products is an essential aspect of food safety efforts, aimed at protecting consumers’ health protection [ 19 ].…”

Occurrence and risk characterization of aflatoxin M1 in milk samples from southeastern Iran using the margin of exposure approach

“…Aflatoxins are the most well‐known group of mycotoxins that are mainly produced by Aspergillus flavus and Aspergillus parasiticus (Ismail et al, 2018 ). Among aflatoxins, types B1, B2, M1, G1, and G2 are more important with respect to food hygiene and safety (Corassin et al, 2022 ; Zain, 2011 ). If lactating animals are fed aflatoxin‐B1 (AFB1) contaminated feeds, the toxin is metabolized in the animals' liver and converted to AFM 1 to appear in the animal's milk, urine, and feces as one of the excretory metabolites (Nguyen et al, 2020 ).…”

“…Therefore, a maximum permissible limit is introduced for the concentration of this toxin in dairy products in most countries to protect consumers from the dangers of AFM 1 exposure, especially infants and children. The maximum permissible limit of AFM 1 in milk is 50 and 500 ng/L in the European Union and the US, respectively (Administration, 2000;Commission, 2006b). However, the maximum standard allowance of AFM 1 concentration in all types of milk samples in Iran is defined as 100 ng/L (Hashemi, 2016).…”