In this study, we sought to identify a soil stabilizer that can be applied to paddy fields vulnerable to arsenic (As) pollution. To this end, we conducted a pot experiment in which we evaluated the effects of different stabilizers on the bioavailability of As in paddy soil. As candidate stabilizers, we assessed calcium superphosphate (CSP), sulfur, and steel slag, which were applied at the rates of 0.7 and 1.4, 0.1 and 0.2, and 7.0 and 14.0 Ma ha −1 , respectively. On day 67 after rice

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... tation, we detected significantly lower concentrations of As in the solutions of paddy soil treated with 1.4 Ma ha −1 CSP (96.9 µg L −1 ) and 0.2 Ma ha −1 sulfur (207.2 µg L −1 ) compared with the As concentrations in control (314.5 µg L −1 ) and steel slag-treated (268.6-342.4 µg L −1 ) soil. Compared with the As concentrations in control brown rice (0.16 mg kg −1 ), concentrations in brown rice were lowest in the pots treated with 1.4 Ma ha −1 CSP (0.09 mg kg −1 ). Furthermore, in response to CSP treatments, we detected increases in the weight of rice grains (50.0-50.4 g/pot) compared with the control (40.4 g/ pot) and other treatments (26.9-48.1 g/pot), which we speculate could be attributed to the reduction in As toxicity to rice owing to a decline in soil solution As contents and the fertilization effect of the CSP treatment. Collectively, our findings indicate a high-level application of CSP (1.4 Ma ha −1 ) to paddy soil has a comparatively beneficial effect in mitigating the bioavailability of As.