The arsenic contamination of rice in Guangdong Province, the most economically dynamic provinces of China: arsenic speciation and its potential health risk.

Rice is a staple food in China, but it may contain toxic heavy metals. Hence, the concentrations of arsenic (As) species (As(III), As(V), MMA and DMA) were evaluated in 260 rice samples from 13 cities of Guangdong Province, the most economically dynamic provinces of China. The levels of sum concentrations of As species in rice samples varied from non-detect to 225.58 ng g(-1), with an average value of 57.27 ng g(-1). The mean concentrations of the major As species detected in rice samples were in the order As(III) (34.77 ng g(-1)) > As(V) (9.34 ng g(-1)) > DMA (8.33 ng g(-1)) > MMA (4.82 ng g(-1)). The rice samples of Guangdong Province were categorized as inorganic As type. Significant geographical variation of As speciation existed in rice samples of 13 cities of Guangdong Province by chi-square test (p < 0.05). The average human weekly intakes of inorganic As via rice consumption in Guangdong Province, southern China, were 1.91 µg kg(-1) body weight. Hazard quotients of total As via rice consumption of adults in 13 cities ranged from 0.06 to 0.30, indicating the As contents in rice from Guangdong Province had no potential adverse impact on human health.