Dietary exposure assessment and risk characterization of mycotoxins in lactating women: Case study of São Paulo state, Brazil

[Display omitted] •Mycotoxin co-occurrence in foods consumed by lactating women in São Paulo, Brazil.•High dietary mycotoxin exposure of lactating women in Pirassununga, Brazil.•Margin of Exposure (MoE) for aflatoxins demonstrated a high cancer risk (MoE 1).•Concerns on the possible transfer of residual mycotoxins into breast milk. The exposure and risk characterization of lactating women to aflatoxins (AFs), fumonisins (FBs), ochratoxin A (OTA) and zearalenone (ZEN) due to consumption of different types of food products in Pirassununga, São Paulo, Brazil, was assessed. Lactating women (N = 74) provided samples of foods stored and available at their households between April-August/2018, totaling 184 samples. Mycotoxins were determined in food samples by liquid chromatography-tandem mass spectrometry. According to findings, 20% (n = 36) of all food samples were contaminated with AFs at median concentrations ranging from 9.2 to 18.5 µg/kg, while OTA was detected only in three samples (rice, bread and pasta) at concentrations of 22.3, 23.8 and 48.7 µg/kg, respectively. ZEN was detected in 34 samples (18%) at median levels of 62–195 µg/kg, and FBs at median levels of 58–1546 µg/kg was observed in 22 samples (12%). Moreover, the concentration of AFs, OTA, ZEN and FBs exceeded their respective maximum permitted levels in 11 (6%), 3 (2%), 8 (4%) and 5 (3%) from total samples, respectively. Twenty-eight samples (15%) were contaminated with two or three types of mycotoxins. Corn products contributed for the highest mean probable daily intakes (PDI) of AFs (0.119 ± 0.193 µg/kg body weight (bw)/day), ZEN (0.325 ± 0.097 µg/kg bw/day) and FBs (2.936 ± 1.541 µg/kg bw/day), while wheat-based products contributed for the highest PDI of OTA (0.035 ± 0.028 µg/kg bw/day). The Margin of Exposure (MoE) value for AFs (3.72) demonstrated a high cancer risk (MoE 1) via consumption of the investigated food products. Results of this trial indicate high exposure levels of lactating women to dietary mycotoxins in the studied area, which warrant concern about the possible transfer of residual mycotoxins into breast milk.