关键词: 水稻, Cd污染稻田, 锑矿区, 有机肥, 叶面喷施, 健康风险

Abstract: The mining and smelting of antimony ore cause serious pollution of paddy soils in mining areas, with cadmium (Cd) pollution being overlooked. In this study, 21 pairs of rice and rhizosphere soil samples during the rice maturation period were collected from rice fields around an antimony mine in Dushan County, Guizhou Province. Contents of Cd in soil and rice grains were analyzed. Results showed that the mean Cd contents in soil and rice grains were 1.31±3.46 and 0.38±2.82 mg·kg^-1, respectively, with exceedance rates of 66.7% and 14.3%, indicating a significant risk of Cd pollution. A field remediation experiment on three rice cultivars was conducted with three treatments, applying organic fertilizer to the soil, foliar spraying of fulvic acid zinc, and a combination of both. The results showed that organic fertilizer increased soil pH and thereby reduced soil available Cd content and the Cd concentrations in rice grains. Compared to the control group, the organic fertilizer treatment reduced the Cd concentrations in rice grains of Jingliangyou 543 and Guang No. 8 You 199 by 41.7% and 42.0%, respectively, with no significant effect on Jiazaoyou 1792. Foliar application of zinc fulvic acid + organic fertilizer significantly reduced the Cd concentration in Jiazaoyou 1792 grains by 42.5%. Jiazaoyou 1792 exhibited the lowest Cd content in rice grains and the highest yield. After remediation, the health risks associated with consuming rice were reduced; however, the carcinogenic risk (CR) retained above 10^-4. For adults, the non-carcinogenic risk (HQ) of consuming Jiazaoyou 1792 was below 1. For children, HQ was also below 1 when consuming Jiazaoyou 1792 treated with foliar application of zinc fulvic acid + organic fertilizer group. Additionally, the combined treatment achieved the greatest reduction in CR, decreasing by 78.7% and 76.8% for children and adults, respectively. Therefore, it is recommended to grow Jiazaoyou 1792 in the typical karst area and adopt foliar spraying zinc fulvic acid + organic fertilizer to mitigate Cd risks.

Key words: rice, Cd-polluted paddy soil, antimony mining area, organic fertilizer, foliar application, health risk