HEALTH RISK ASSESSMENT OF HEAVY METALS IN RICE, POTATO AND RADISH LEAVES GROWN IN DINAJPUR REGION

Abstract

Food security with its diverse and emerging issues of different toxic Heavy Metals (HMs) including metalloids has received global attention due to their inextricable association with human health. Rice is one of the integral foods in the dietary chart by which HMs are easily transmitted from the environment to the human body. Until now, HMs associated hazardous risk in Bangladeshi normal Swarna rice (NR) has not been studied. The study was aimed to assess hazardous risk of HMs (As, Cd, Cr, Pb and Zn) in NR from three sub-districts including Kaharole (SR01, SR02, SR03), Biral (SR04, SR05, SR06), and Sadar (SR07, SR08, SR09) of Dinajpur, and reduction of HMs from rice by special cooking with fermentation approaches. The level of HMs was determined using Flame Atomic Absorption Spectrophotometer. In a comparative study of NR, boiled rice (BR), and fermented rice (FR, panta-bhat); levels of As, Cd, Cr, and Zn in all samples were below or lower than the individual metal’s safe limit. In contrast, Pb concentrations were detected 0.2582, 0.9028, 0.9164, 0.7303, 0.8574, 0.6440, 0.6622 mg/kg in SR02, SR04, SR05, SR06, SR07, SR08, and SR09 of NR samples, which are noticeably higher than the Pb safe limit (0.2 mg/kg), respectively. The hazard index (HI) of NR samples SR01 to SR03, and SR04 to SR09 were obtained between 0.3 to 0.99 and 1.795 to 2.06, respectively. Notably, HI declined below the normal limit 1 for SR01 to SR05 samples of BR and FR, respectively. Additionally, cumulative carcinogenic risk (CCR) declined by 4.1-, 4.13-, 6.54-, 5.6-, 2.88-folds in BR, and 5.34-, 10.54-, 9.10-, 7.22-, 4.55-folds in FR compared to NR, respectively. The concentration of HMs in potato and radish leaves also give information to detect the health risk of the local consumers in the Dinajpur region. The reduction of HI and CCR from NR occurred due to the purging of HMs by boiling along with cooking associated panta-bhat (PB) fermentation, which provides useful information on health risk reduction for the local rice consumer. It is concluded that the boiling and fermentation of rice in this condition is a great strategy of leaching the HM that reverses the natural pollution of HMs in rice. Further research should be conducted on other vegetables and rice grown in this region to evaluate the potential total hazard quotient (THQ) and carcinogenic health risk from HMs. Moreover, the HI reduction strategy should be conducted on the other rice varieties grown in Aman and Boro season in this area, as well as arsenic endemic areas in Bangladesh. This HI reduction strategy of rice may provide new insights into the food security of Bangladeshi people.