Abstract: Objective To characterise the contamination profile of chromium (Cr), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in commercially available rice in Hubei Province, China, and to evaluate the attendant health risks arising from rice consumption. Methods Rice samples were collected from various retail markets in Hubei Province. Following microwave digestion pretreatment, the concentrations of Cr, As, Cd, Hg, and Pb were determined using inductively coupled plasma mass spectrometry (ICP-MS) in accordance with National Food Safety Standard: Determination of Multi-Elements in Food (GB 5009.268-2016). The measured levels were evaluated against the maximum permissible limits specified in National Food Safety Standard: Maximum Levels of Contaminants in Food (GB 2762-2022). Dietary exposure was calculated using the point-estimate model recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), while health risks were assessed via the exposure assessment model proposed by the U.S. Environmental Protection Agency (USEPA). Results Among 246 rice samples, the detected concentration ranges were as follows: Cr (ND-0.279 mg/kg), As (0.040-0.204 mg/kg), Cd (ND-0.211 mg/kg), Hg (ND-0.044 62 mg/kg), and Pb (ND-0.666 mg/kg). The non-carcinogenic hazard quotients (HQ) for each heavy metal followed the order As>Cd>Hg>Cr>Pb, with only As exceeding the threshold (HQ>1). The cumulative lifetime excess cancer risks of the three heavy metals (Cr, As, Cd) for different population groups were 2.02×10^-4, 1.62×10^-4, 1.13×10^-4, 8.29×10^-5, 3.55×10^-4, and 3.10×10^-4, respectively. Conclusion While the overall heavy metal contamination in commercially available rice from Hubei Province remains within safe limits, certain elements-particularly arsenic-warrant regulatory attention due to their elevated risk potential.

Key words: Rice, Heavy metal contamination, Dietary exposure, Health risk assessment, Food safety, Contaminant limits, Inductively coupled plasma mass spectrometry （ICP-MS）