Ochratoxin A and Portuguese children: Urine biomonitoring, intake estimation and risk assessment

Ochratoxin A (OTA) is a mycotoxin detected worldwide. Urine biomonitoring is a more realistic and non-invasive way to assess exposure when compared to traditional methods based on food occurrence and consumption data. Few studies have investigated children's exposure to OTA, although it is a more susceptible population. Our main goal was the OTA biomonitoring in urine of Portuguese children to better characterize the health risk of this population. The validated analytical methodology was based on an immunoaffinity clean-up, followed by LC-FD. First morning samples were collected, between 2018 and 2019, from 85 healthy children, 41 boys and 44 girls, aging between 2 and 13 years old. Overall, from the 85 analysed samples 79 (92.94%) were found positive. The average OTA concentration level was of 0.020 ng/mL (29.41 ng/g of creatinine), with a maximum value of 0.052 ng/mL (114.45 ng/g of creatinine). No statistical differences were found between the OTA contamination levels, the anthropometric data and dietary habits considered. Depending on the excretion rate considered for the PDI calculation, the risk assessed for the average OTA contamination varied from 10% to 194%, indicating a potential concern. This is the first study regarding OTA exposure in Portuguese children, showing their clear exposure.