Author
MITCHELL, NICOLE - Michigan State University | |
Riley, Ronald | |
EGNER, PATRICIA - Michigan State University | |
GROOPMAN, JOHN - Johns Hopkins University | |
WU, FELICIA - Michigan State University |
Submitted to: Journal of Exposure Science and Environmental Epidemiology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/22/2015 Publication Date: 1/6/2016 Citation: Mitchell, N.J., Riley, R.T., Egner, P.A., Groopman, J.D., Wu, F. 2016. Chronic aflatoxin exposure in children living in Bhaktapur, Nepal: Extension of the MAL-ED study. Journal of Exposure Science and Environmental Epidemiology. doi:10.1038/jes.2015.87. Interpretive Summary: Exposure to dietary aflatoxin, a mycotoxin common in maize and groundnuts in warm regions worldwide, has been associated with childhood stunting in sub-Saharan Africa. The mechanism by which aflatoxin may induce growth impairment is not yet known and is likely multifaceted. In an effort to further our understanding of growth impairment in relation to mycotoxins and other risk factors, biospecimens from a cohort of children enrolled in the Bhaktapur, Nepal MAL-ED study were assessed for aflatoxin exposure at 15, 24, and 36 months of age. The World Health Organization estimates that 38.8 and 59.0% of children, living in rural areas of Nepal, are at least 2 standard deviations below the median in weight/age and height/age, respectively. Results from this preliminary analysis demonstrated significant chronic aflatoxin exposure in children. Ninety-one percent of samples tested positive for the aflatoxin biomarker AFB1-lysine. While the means were slightly lower than those most often observed in sub-Saharan Africa, the ranges were similar. Only one sample out of 50 tested positive for fumonisin, another mycotoxin commonly found in maize that has also been linked to stunting. This data clearly depicts aflatoxin exposure in children residing in Bhaktapur at levels that have been associated with poor child growth. Future work will analyzed the relationships between aflatoxin levels, growth, and other risk factors collected by the MAL-ED study. Technical Abstract: Fumonisin B1 (FB1) and aflatoxin B1 (AFB1) are toxic chemicals produced by molds. The molds that produce these two toxic chemicals are commonly found in corn and their co-occurence in corn has been demonstrated in many surveys. This study was conducted because it is suspected that exposure to either aflatoxin or fumonisin or both might contribute to malabsorption and/or enteric disease that is suspected to be involved in growth retardation in young children in areas of the world where cereals and groundnuts are important constituents of the daily diet and are likely to be contaminated with aflatoxin and/or fumonisin. Nepal is one of the sites being studied by the Foundation of the National Institute of Health MAL-ED study to better understand the factors that contribute to the high level of childhood stunting in many developing countries worldwide. The results of this study in Nepal show that most children are exposed to aflatoxin but very few are exposed to fumonisin. Aflatoxin has been associated with childhood stunting in sub-Saharan Africa. Thus, aflatoxin but not fumonisin is a possible risk factor for growth retardation in the Nepalese child cohort being studied in the MAL-ED project. |