South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, China.
Guangdong Engineering Technology Research Center of Heavy Metal Pollution Control and Restoration in Farmland Soil, Guangzhou, Guangdong, China.
Environ Sci Pollut Res Int. 2022 Sep;29(44):66479-66489. doi: 10.1007/s11356-021-18344-y. Epub 2022 May 3.
Arsenic is known to be a notorious human carcinogen and rice consumption is becoming the primary human exposure route for As, especially in many Asian countries. As one of redox-sensitive elements in soil, sulfur plays an indisputable role in controlling As behaviors. However, information on the effects of persulfe (PS) on the toxicity and accumulation of As in rice plant under flooded conditions is limited. Therefore, a pot experiment was conducted to investigate the effects of PS amendment on the growth and accumulation of As species in rice plants grown in As-contaminated paddy soil. Results revealed that PS application increased the As, Fe, and Mn in porewater at the early stage, and then declined. Application of PS increased the biomass of stem and root, while inhibited the formation of iron plaque on the root surface. The As translocation from root to rice above tissues and accumulation of As species in brown rice were declined by amendment with PS. The inorganic arsenic (iAs) and DMA were the two main species in brown rice, and decreased by 1326% and 4060% respectively upon PS application. The results suggested that amendment with PS might be feasible for reducing the accumulation of As in rice grains grown in As-contaminated paddy soil. However, further detailed studies on the potential soil biogeochemical and physiological mechanisms are recommended.
砷是一种公认的人类致癌物质，而食用大米正成为人类接触砷的主要途径，尤其是在许多亚洲国家。作为土壤中一种氧化还原敏感元素，硫在控制砷行为方面发挥着不可替代的作用。然而，有关过硫酸盐（PS）对淹水条件下水稻植株中砷毒性和积累的影响的信息有限。因此，进行了一项盆栽实验，以研究 PS 改良对砷污染稻田中生长的水稻植株中砷形态的毒性和积累的影响。结果表明，PS 应用在早期增加了孔水中的砷、铁和锰含量，然后下降。PS 的应用增加了茎和根的生物量，同时抑制了根表面铁斑的形成。PS 改良降低了砷从根部向地上组织的转运和糙米中砷形态的积累。无机砷（iAs）和 DMA 是糙米中的两种主要砷形态，PS 处理后分别减少了 13%26%和 40%60%。结果表明，PS 改良可能是减少砷污染稻田中水稻籽粒砷积累的一种可行方法。然而，建议进一步详细研究其潜在的土壤生物地球化学和生理机制。
