Development and Evaluation of a Sensitive Mycotoxin Risk Assessment Model (MYCORAM)

Abstract

The differential risk of exposure to fumonisin (FB), deoxynivalenol (DON), and zearalenone (ZEA) mycotoxins to the South African population, residing in the nine Provinces was assessed during a cross-sectional grain consumer survey. The relative per capita maize intake (g/day) was stratified by gender, ethnicity, and Province and the probable daily intake (PDI) for each mycotoxin (ng/kg body weight/day) calculated utilizing SPECIAL and SUPER dry milled maize fractions representing different exposure scenarios. Men consumed on an average more maize (173 g/day) than women (142 g/day) whereas the black African ethnic group had the highest intake (279 g/day) followed by the Colored group (169 g/day) with the Asian/Indian and White groups consuming lower quantities of 101 and 80 g/day, respectively. The estimated mean PDIs for the various subgroups and Provinces, utilizing the different dry milled maize fractions, were below the provisional maximum tolerable daily intake (PMTDI) for each mycotoxin. A distinct and more sensitive mycotoxin risk assessment model (MYCORAM) for exposure, stratified by Province and ethnicity were developed utilizing specific maize intake increments (g/kg body weight/day) that provides information on the percentage of the population exposed above the PMTDI for each mycotoxin. Evaluation of the MYCORAM utilizing commercial and EXPERIMENTALLY DERIVED: SPECIAL milling fractions, containing predefined mycotoxins levels, predicts the percentage of maize consumers exposed above the respective PMTDI. Safety modeling using the MYCORAM could also predict a maximum tolerated level adequate to safeguard all South African maize consumers including the most vulnerable groups.

Rural Subsistence Maize Farming in South Africa: Risk Assessment and Intervention models for Reduction of Exposure to Fumonisin Mycotoxins

“…In South Africa, an estimated four million people engage in smallholder agriculture [45], with maize being the major crop and staple food in the country. Maize-based products are consumed by 67 to 83% of South Africans, and the mean consumption per day in rural areas is estimated between 476 and 690 g per person [46]. Maize produced in these areas is often affected by pre- and postharvest damage, of which fungal infection is one of the most significant constraints.…”

“…However useful this model may be, it does not represent real-time maize intakes or body weight data. A study conducted in collaboration with a prominent South African grain-based manufacturing company, in the form of a national cross-sectional study, provided a unique opportunity to collect relevant sociodemographic information, maize dietary intakes and body weights of commercial maize consumers across South Africa [46]. Using this data and building on the previous model, the Mycotoxin Risk Assessment Model (MYCORAM) was developed for three relevant mycotoxins FB, DON and ZEA.…”

“…Arbitrary levels of the three mycotoxins were plotted against specific maize intake categories (g kg −1 body weight day −1 ) and estimates the percentage of maize consumers exposed above the PMTDI for each mycotoxin (Figure 2). With the additional sociodemographic data that was available [46], this model was stratified by provincial region ( n = 9). The purpose of this model was to calculate maximum levels to protect South African maize consumers.…”

“…Mycotoxin Risk Assessment Model (MYCORAM) for total fumonisin B (FB T ), deoxynivalenol (DON) and zearalenone (ZEA): Percentages of the South African maize consumers stratified by province equal or above the respective mycotoxin provisional maximum tolerable dietary intake (PMTDI) (adapted from Burger et al [46], 2014, Oxford University Press). EC: Eastern Cape; FS: Free State; GP: Gauteng; KZN: KwaZulu-Natal; LP: Limpopo; MP: Mpumalanga; NC: Northern Cape; NW: North West; WC: Western Cape.…”

Detoxification of the Fumonisin Mycotoxins in Maize: An Enzymatic Approach

“…The FumD FB reduction method in maize could also find application in communities utilising home-grown maize as a main dietary staple and known to be exposed above the tolerable daily intake levels, i.e., a PMTDI of 2 µg/kg/bw/day [36,37]. To decrease the risk of FB exposure, culturally sensitive, practical and biologically based methods of reduction are relevant and need to be implemented [1].…”