Cooked Rice Products (<i>Kwenkwen, Jollof, </i><i>Fried-rice, Angwamo </i>and<i> Kanzo</i>) as Sources of Polyaromatic Hydrocarbons and a Potential Public Health Concern

Cooking methods for rice products may also present contaminating polycyclic aromatic hydrocarbons (PAHs), which are known to be carcinogenic. This study collected a total of 54 different cooked rice products from the study area and extracts were made using the Quick, Easy, Cheap, Effective, Rugged and Safe (QuECheRS) method. After quantifying the PAH’s concentrations using HPLC, standard protocols were used to determine the exposure of key PAHs (total benzo [a] pyrene (BaP), ΣPAH4, ΣPAH8) and the risks of consumers based on the rice consumption pattern from 760 participants. The results indicated 11 congeners, presenting 2-methylnaphthalene as the highly contaminating PAH (61.11%) and total benzo [a] pyrene (BaP) as the lowest (18.52%) contaminating PAH. The ΣPAH4 and the ΣPAH8 types presented 5th-95th percentiles concentrations ranging between 0.302 and 9.275 mg/kg for ΣPAH4 and between 0.304 and 9.315 mg/kg for ΣPAH8 respectively. However, benzo [a] pyrene (BaP)s concentration ranged between 0.050 and 1.526 mg/kg. The 95th percentile exposure (1.28-8.04 mg/kg (bw)-day), margin of exposure (MoEs) (4), and incremental life time cancer risk (ILTCR) (1×10-3 >10-4) indicated high risk among the consumers. All eight non-carcinogenic PAHs showed significantly high hazard indices (HI >1) except for outliers which were isolated cases. Thus, the study suggests a high-risk predisposition of the top 5% of the consumer population of such cooked rice products. Constant monitoring is therefore warranted to maintain safety.