Dietary Exposure and Natural Occurrence of Total Aflatoxins in Basmati Rice of Pakistan

Abstract

This study presents the assessment of total aflatoxins (TAFs) in basmati rice (brown, 1,081; white, 1,170) collected from different areas of Punjab, Pakistan, during 2010 to 2015. Due to the carcinogenicity of TAFs, daily dietary exposure is also evaluated based on rice consumption survey data. Methodology was standardized by matrix spike recoveries at four fortification levels (0.1, 0.5, 2.5, and 12.5 ng/g) for TAFs (aflatoxins B1 [AFB1], B2 [AFB2], G1 [AFG1], and G2 [AFG2]). The present study reveals that 1,750 samples (77.74%) were tainted with AFB1, whereas TAFs were detected in 370 samples (16.43%). Of positive samples, 854 brown rice samples (79%) were positive for AFB1, and 154 samples (14.24%) were contaminated with TAFs. For white rice, 896 samples (76.58%) were contaminated with AFB1, whereas 205 samples (18.46%) were found positive for TAFs. Study findings were used to construct a frequency distribution, and AFB1 levels were also compared against permissible levels of TAFs (10 ng/g) as legislated by the European Commission. Results further revealed that daily dietary exposure of TAFs ranged from 0.51 to 10.22 ng/kg of body weight per day, which exceeds the permissible limit of 1 ng/kg of body weight per day as defined by the Joint FAO/WHO Expert Committee on Food Additives.