Water management such as drainage for creating aerobic conditions is considered to be an adequate method for reducing the accumulation of arsenic (As) in rice grains; however, it is difficult to conduct drainage operations in some areas that experience a lengthy rainy season as well as in soils with poor drainage. In this regard, application of oxygen-releasing compounds (ORCs) may be an alternative method for maintaining aerobic conditions even under flooding in paddy soils. Therefore, a pot experiment was conducted to investigate the effects of application of an ORC, calcium peroxide (CaO₂), on the growth and accumulation of As in rice plants grown in As-contaminated paddy soils. The rice plants were grown in two soils with different characteristics and As levels, and all of the tested soils were treated with 0, 5, 10, and 20 g CaO₂ kg⁻¹. Results revealed that the concentration of As and the distribution of arsenite in the pore water of all tested soils was reduced by CaO₂ application. In addition, the grain yields increased and the concentration of inorganic As in brown rice decreased by 25–45% upon CaO₂ treatment of low-As-level soils (<16 mg kg⁻¹). However, the effect of CaO₂ application on the accumulation of inorganic As in brown rice in As-enriched soils (>78 mg kg⁻¹) could not found in this study, due to the rice plant suffered from serious As phytotoxicity. It suggests that CaO₂ amendment may be suitable for reducing the As concentration of rice grains grown in low-As-level paddy soils, but for As-enriched soils, the proposed CaO₂ application method is not feasible.

诸如排水等有氧条件的水管理被认为是减少稻米中砷（As）积累的适当方法。但是，在雨季较长的地区以及排水不良的土壤中，很难进行排水作业。在这方面，即使在稻田中淹水的情况下，施用释氧化合物（ORC）可能也是维持有氧条件的替代方法。因此，进行了盆栽实验以研究ORC，过氧化钙（CaO ₂），了解砷在受砷污染的水稻土中生长的水稻植株中的生长和积累情况。水稻植株生长在两种具有不同特性和砷含量的土壤中，所有被测土壤均用0、5、10和20 g CaO ₂ kg ^-1处理。结果表明，CaO _2的施用降低了所有被测土壤孔隙水中砷的浓度和砷的分布。此外，CaO ₂处理低砷水平土壤（<16 mg kg ^-1）后，谷物产量增加，糙米中无机砷的浓度降低了25–45％。但是，CaO ₂的作用由于水稻植株具有严重的As的植物毒性，因此在富砷土壤（> 78 mg kg ^-1）中未发现对糙米中无机As积累的应用。这表明CaO ₂改性剂可能适合降低低As水平稻田土壤中水稻籽粒的As浓度，但是对于富As土壤，提出的CaO ₂施用方法是不可行的。