Medicinal and spice herbs have been of great importance since the ancient ages. People have relied much on them to fulfill their healthcare needs and as ingredients of diverse cuisines. Currently, the cultivation of medicinal plants based on agro-chemicals has posing lives because chemicals contain toxic elements, including Cadmium. This research determined the Cd concentrations oin soil and medicinal and spice plants, and determined the efficiency of three binding agents on immobilization of Cd in three soil types sampled in Karanganyar. Soil cores and rhizomes were sampled and analyzed for soil properties and Cd content. Three soil types were incubated in triplicate. Each soil (5 g) was treated with 0.2 g of dolomite, 1.0g of charcoal and organic fertilizer by adding 8 ml of distilled water in a 50 ml tube, and then incubated for 24 days after having been shaken for 16 h. were added 1ml of (HNO3 and 3 ml KClO4 to the mixture. The mixture was first heated at 80oC and then at 130oC till the orange smoke gets finished. Finally Cd was extracted with solution of 0.01 CaCl2 (20 ml), and measured by AAS. The results showed that Cd in all the investigated villages still below the limits (1.0 mg Cd/kg). In soils Cd ranged from 0.224 to 0.354 mg Cd/kg, while in herbs ranged from 0.0285 to 0.0594 mg Cd/kg. Dolomite showed the highest efficiency (95.43%) followed by organic fertilizer (92.64%) and charcoal (91.53%) in Alfisols. In general dolomite wasthe better binding agent in each location, while the lowest efficiency was recorded with organic fertilizer (89.30%) in Mediterranean soils from Kemuning.
Keywords: Immobilization; medicinal plants; Cadmium; binding agents; efficiency.