Assessment of aflatoxin exposure among young children in Ethiopia using urinary biomarkers.

The direct measurement of biomarkers of exposure in biological fluids such as urine has become important for assessing aflatoxin exposure in humans as it is the only tool that integrates exposures from various routes. For this reason, a study was conducted to assess aflatoxin exposure among young children in Ethiopia using urinary biomarkers. A cross-sectional study was conducted in ten Woredas (Districts) from Amhara and Tigray regional states of Ethiopia including 200 children (aged 1-4 years). A total of 200 urine samples were collected from 200 children and assessed for the levels of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and aflatoxin M1 (AFM1) using a validated LC-MS/MS method. Aflatoxins were detected in 34/200 (17%) of the urine samples whereby four out of five analysed aflatoxins were detected. AFM1 was detected in 14/200 (7%) of the urine samples in a range of 0.06-0.07 ng/mL. AFB2, AFG2 and AFG1 were detected in respectively 9/200 (4.5%), 6/200 (3%) and 5/200 (2.5%) of the urine samples whereas AFB1 was not detected in any of the samples. In this study, there was no association between the different malnutrition categories (stunted, wasting and underweight) and aflatoxin exposure. However, the biomarker analysis showed a clear exposure of young children to aflatoxins. Therefore, awareness to the public is important to prevent potential health consequences of aflatoxins.

Human biomonitoring of multiple mycotoxins in the Belgian population: Results of the BIOMYCO study.

Mycotoxins are important food contaminants responsible for health effects such as cancer, nephrotoxicity, hepatotoxicity or immunosuppression. The assessment of mycotoxin exposure is often based on calculations combining mycotoxin occurrence data in food with population data on food consumption. Because of limitations inherent to that approach, the direct measurement of biomarkers of exposure in biological fluids has been proposed as a suitable alternative to perform an accurate mycotoxin exposure assessment at individual level. For this reason, the BIOMYCO study was designed to assess mycotoxin exposure in Belgian adults and children using urinary biomarkers of exposure. Morning urine was gathered in a representative part of the Belgian population according to a standardised study protocol, whereby 155 children (3-12 years old) and 239 adults (19-65 years old) were selected based on random cluster sampling. These urine samples were analysed for the presence of 33 potential biomarkers with focus on aflatoxins, citrinin (CIT), fumonisins, trichothecenes, ochratoxin A (OTA), zearalenone and their metabolites using two validated LC-MS/MS methods. Nine out of the 33 analysed mycotoxins were detected whereby deoxynivalenol (DON), OTA, CIT and their metabolites were the most frequently detected. Deoxynivalenol-15-glucuronide was the main urinary DON biomarker and was found in all urine samples in the ng/mL range. Furthermore deoxynivalenol-3-glucuronide was quantified in 91% of the urine samples collected from children and in 77% of the samples collected from adults. Deoxynivalenol was detected in 70% and 37% of the samples of children and adults respectively. For the first time deepoxy-deoxynivalenol-glucuronide was detected in children's urine (17%). In the samples collected by adults, the prevalence was 22%. Whereas all these mycotoxins contaminated the urine samples in the ng/mL range, CIT and OTA were present in much lower concentrations (pg/mL). OTA contaminated 51% and 35% of the samples collected by children and adults respectively. CIT and its metabolite were present in 72% and 6% of children's urine, whereas they contaminated 59% and 12% of adult's urine. Finally, α-zearalenol and ß-zearalenol-14-glucuronide were found in respectively one and two samples from adults. The exposure to DON, OTA and CIT was compared between subgroups and urinary mycotoxin concentrations differed significantly among age and gender. Based on the urinary levels, the daily intake of DON and OTA was estimated and evaluated whereby, depending on the used method, 16-69% of the population possibly exceeded the tolerable daily intake for DON and 1% for OTA. The BIOMYCO study is the first study whereby a multi-toxin approach was applied for mycotoxin exposure assessment in adults and children on a large-scale. Moreover, it is the first study that described the exposure to an elaborated set of mycotoxins in the Belgian population. Biomarker analysis showed a clear exposure of a broad segment of the Belgian population to DON, OTA and CIT. The risk assessment based on these data indicates a potential concern for a number of individuals whereby young children need special attention because of the relatively higher food intake per kg body weight.

Assessment of mycotoxin exposure in the Belgian population using biomarkers: aim, design and methods of the BIOMYCO study.

Mycotoxins are harmful food contaminants. Currently, human exposure assessment to these toxins is often based on calculations combining mycotoxin occurrence data in food with population data on food consumption. Because of limitations inherent to that approach, biomarkers have been proposed as a suitable alternative whereby a more accurate assessment of exposure at the individual level can be performed. The BIOMYCO study is designed to assess human mycotoxin exposure using urinary biomarkers of exposure. Over the different seasons of 2013 and 2014, morning urine is gathered in a representative part of the Belgian population according to a designed study protocol, whereby 140 children (3-12 years old) and 278 adults (19-65 years old) are selected based on random cluster sampling stratified for sex, age and geographical areas. Every participant completes a food frequency questionnaire to assess the consumption of relevant foodstuffs (n = 43) of both the day before the urine collection and the previous month. Validated multi-toxin LC-MS/MS methods are used to analyse aflatoxins, fumonisins, ochratoxin A, trichothecenes, zearalenone and their metabolites in morning urine. The study protocol is approved by the ethical committee of the Ghent University Hospital. Within this paper, study design and methods are described. The BIOMYCO study is the first study whereby a multi-toxin approach is applied for mycotoxin exposure assessment in adults and children on a large scale. Moreover, it is the first study that will describe the exposure to an elaborated set of mycotoxins in the Belgian population. In first instance, descriptive analysis will be performed, describing the exposure to mycotoxins for the child and adult group. Exposure of different subgroups will be compared. Furthermore, correlations between the mycotoxin concentrations measured and the food consumption reported will be estimated to explore whether the mycotoxin exposure could be explained by the consumption of certain foods.