Investigations on prevalence of aflatoxin contamination in major groundnut growing states of India, influence of soil characteristics and farmers’ level of awareness
Food safety issues are of major concern in groundnut due to aflatoxin
contamination by Aspergillus flavus. Monitoring aflatoxin
prevalence and understanding the factors responsible can provide
useful information for devising effective management strategies.
The present study focused on mapping the pre-harvest
aflatoxin contamination in India along with its determining factors.
A comprehensive survey was undertaken during 2012-2014
in four major groundnut growing States such as Andhra Pradesh,
Gujarat, Karnataka, and Tamil Nadu. Pod (n=2434) and rhizospheric
soil samples (n=1322) were collected to ascertain A. flavus
populations and pre-harvest aflatoxin contamination. Further,
kernel aflatoxin levels were correlated with soil organic carbon,
available calcium and pH levels in the fields from where the samples
were collected. Farmers’ awareness on aflatoxin problem
was also determined using a semi-structured questionnaire. Our
results indicate wide variations in the occurrence of pre-harvest
aflatoxin contamination levels of kernels among different States
(0 - 5486 ppb) and samples within States. Detectable levels of
aflatoxins (>1ppb) were highest in Karnataka (70.5%), whereas
it was lowest in Andhra Pradesh (32.9%). Correlation studies
revealed that aflatoxin contents were positively associated with
soil pH (r = 0.54-0.99) and A. flavus populations (r = 0.63 in
Gujarat; r = 0.75 in Karnataka) whereas soil organic carbon and
available calcium were negatively correlated with toxin levels in
kernels (r = -0.99). Farmers’ awareness was considerably poor
in all the States under survey. Overall, our results suggest the
prevalence of aflatoxin contamination in major groundnut growing
areas in India, and influence of certain edaphic factors