The tuber of Pinellia ternata is commonly used in Chinese medicine to treat diseases such as coughs and inflammation. However, it is usually planted in soils contaminated with cadmium (Cd), which accumulates in the tuber and reduces its quality. Consumption of Cd-contaminated tuber imposes potential human health risk. In this study, the ground granulated blast-furnace slag (GGBS) (an industrial waste) is proposed as a soil amendment to reduce the Cd uptake by P. ternata and at the same time promote its growth. Field soil (silty gravelly sand) contaminated with 1.5 mg kg^-1 of Cd was collected from Guizhou, China. The growth of P. ternata in 0, 3, and 5% GGBS amended soil was investigated in a temperature and humidity-controlled chamber. It was found that soil amended with 3 and 5...[ Read more ]

The tuber of Pinellia ternata is commonly used in Chinese medicine to treat diseases such as coughs and inflammation. However, it is usually planted in soils contaminated with cadmium (Cd), which accumulates in the tuber and reduces its quality. Consumption of Cd-contaminated tuber imposes potential human health risk. In this study, the ground granulated blast-furnace slag (GGBS) (an industrial waste) is proposed as a soil amendment to reduce the Cd uptake by P. ternata and at the same time promote its growth. Field soil (silty gravelly sand) contaminated with 1.5 mg kg^-1 of Cd was collected from Guizhou, China. The growth of P. ternata in 0, 3, and 5% GGBS amended soil was investigated in a temperature and humidity-controlled chamber. It was found that soil amended with 3 and 5% GGBS, significantly (P<0.05) reduced Cd concentration in tuber by 45 and 50%, respectively, compared to control treatment, which is below the limit for herbal medicinal products proposed by the World Health Organization. Addition of 3 and 5% GGBS, significantly (P<0.05) increased the dry mass of tuber by 34 and 54%, respectively, compared to control treatment. Soil amended with 5% GGBS increased the diameter and volume of tuber by 16 and 50% which was significantly (P<0.05) higher compared to control treatment. 3 and 5% GGBS, significantly (P<0.05) increases LAI by 29 and 30%, RAI by 65 and 66%, respectively, compared to control treatment. 58% (P<0.05) increment of suction is observed in both soils amended with 3 and 5% GGBS. Compared to control, soil amended with 3 and 5% GGBS has exhibited higher AEV and higher water retention ability. Results of the study indicate that the use of 5% GGBS can significantly (P<0.05) reduce the Cd concentration in the tuber of P. ternata and improve its growth.