Analysis of Arsenic concentration and its speciation in rice of different markets of Pakistan and its associated health risk

Abstract Arsenic (As) is one of the most toxic metalloids, released to environment from both natural and anthropogenic sources. Among different species of As, inorganic As (iAs) is more toxic than organic As (oAs). Among food stuffs, rice is considered as one of the most important exposure routes of As for human. This study was conducted to quantify total As (TAs) and its species (arsenate (AsIII) and arsenite (AsV), monomethylarsenic (MMA) and dimethyarsenic (DMA) in rice samples collected from different wholesale markets of various main cities present in Pakistan. TAs was detected with the help of ICPMS (inductively coupled plasma mass spectroscopy), while As species were detected with the help of LC-ICPMS (liquid chromatography inductively coupled plasma mass spectroscopy). The concentration of oAs was ranged from 8.97 to 3.94 ug/kg, while iAs concentration was ranged from 35.0 to 21.0 ug/kg. Among As species AsIII was highest (27.0 ug/kg) followed by AsV (8.33 ug/kg). According to the findings, all samples were shown TAs concentration below permissible limit (0.5 mg/kg) as set by WHO (2001). The current study also demonstrated that the values of estimated daily intake (EDI), hazard quotient (HQ) and incremental lifetime cancer risk (ILTCR) were also very low and could not possess a potential risk for the consumers. This study concluded that the rice produced and consumed in Pakistan is of good quality and considered safe for human health regarding As contamination.