Aflatoxin B1 in rice: effects of storage duration, grain type and size, production site and seasonAFB1 in rice marketed in Lebanon

Abstract

Our study aimed to evaluate the AFB1 levels in packed rice marketed in Lebanon and determine the exposure to this toxin from the rice consumption. A total of 105 packed white, parboiled and brown rice bags were collected. ELISA was used to measure AFB1. A comprehensive FFQ was filled by 500 participants to determine the patterns of rice consumption and subsequently the exposure levels to AFB1 from the rice consumption in Lebanon. AFB1 was detected in all rice samples (100%). The average concentration ± standard deviation of AFB1 was 0.5±0.3μg/kg. Contamination ranged between 0.06 and 2.08μg/kg. Moisture content in all rice samples was below the recommended percentage (14%). Only 1% of the samples had an AFB1 level above the European Union (EU) limit (2μg/kg). Brown rice had a significantly higher AFB1 level than white and parboiled rice (p=0.02), while a significant difference was found between both collections for the same brands (p=0.016). Packing season, packing country, country of origin, presence of a food safety management certification, grain size, and time between packing and purchasing had no significant effect. Exposure to AFB1 from rice consumption in Lebanon was calculated as 0.1-2 ng/kg bodyweight/day.