Occurrence of aflatoxins and its management in diverse cropping systems of central Tanzania
Loading...
Date
2017
Journal Title
Journal ISSN
Volume Title
Publisher
Springer
Abstract
The staple crops, maize, sorghum, bambara nut,
groundnut, and sunflower common in semi-arid agro-pastoral
farming systems of central Tanzania are prone to aflatoxin
contamination. Consumption of such crop produce, contami-
nated with high levels of aflatoxin B 1 (AFB 1 ), affects growth
and health. In this paper, aflatoxin contamination in freshly
harvested and stored crop produce from central Tanzania was
examined, including the efficacy of aflatoxin mitigation tech-
nologies on grain/kernal quality. A total of 312 farmers were
recruited, trained on aflatoxin mitigation technologies, and
allowed to deploy the technologies for 2 years. After 2 years,
188 of the 312 farmers were tracked to determine whether
they had adopted and complied with the mitigation practices.
Aflatoxigenic Aspergillus flavus and aflatoxin B1 contamina-
tion in freshly harvested and stored grains/kernels were
assessed. A. flavus frequency and aflatoxin production by
fungi were assayed by examining culture characteristics and
thin-layer chromatography respectively. AFB 1 was assayed by
enzyme-linked immunosorbent assay. The average aflatoxin
contamination in freshly harvested samples was 18.8 μg/kg,
which is above the acceptable standard of 10 μg/kg.
Contamination increased during storage to an average of 57.2 μg/kg, indicating a high exposure risk. Grains and oil-
seeds from maize, sorghum, and sunflower produced in
aboveground reproductive structures had relatively low afla-
toxin contamination compared to those produced in geocarpic
structures of groundnut and bambara nut. Farmers who
adopted recommended post-harvest management practices
had considerably lower aflatoxin contamination in their stored
kernels/grains. Furthermore, the effects of these factors were
quantified by multivariate statistical analyses. Training and
behavioral changes by farmers in their post-harvest practice
minimize aflatoxin contamination and improve food safety.
Moreover, if non-trained farmers receive mitigation training,
aflatoxin concentration is predicted to decrease by 28.9 μg/kg
on average.
Description
Journal Article
Keywords
Post-harvest management, Aflatoxin contamination, Crop diversity, Food safety, Sub-Saharan Africa, Tanzania, Confounding factor