Potential of Organic Amendments for Heavy Metal Contamination in Soil-Coriander System: Environmental Fate and Associated Ecological Risk

Pollution by organic wastes and manures is an important problem in tropical and sub-tropical countries and novel solutions for their proper management and valorization are needed. Waste-derived organic manures may increase metal load in the soil-plant ecosystem and food chain, with potential risks to public health. The aim of this work was to evaluate the impact of three manures (poultry waste (PW), press mud (PM), and farmyard manure (FYM)) on heavy metals (HMs) (Cd, Co, Cr, Cu, Pb, Zn, Fe, Mn) toxicity in a soil and coriander (Coriandrum sativum L.) system and their environmental impact (bioaccumulation, pollution load) and the consequent risk to human health via consumption. Results demonstrated that HMs in coriander fluctuated from 0.40 to 0.43 for Cd, 1.84 to 3.52 for Co, 0.15 to 0.16 for Cr, 1.32 to 1.40 for Cu, 0.05 to 0.09 for Pb, 1.32 to 2.51 for Fe, 0.10 to 0.32 for Mn, and 2.01 to 8.70 mg/kg for Zn, respectively. Highest pollution load index value was 2.89 for Cd and Mn showed the lowest (0.005). Daily intake of metal was noticed to be higher for Zn (0.049 mg/kg/day) for PW and lower for Mn (0.0005) at FYM treatment. The health risk index value was <1 and in the range of 2.30-2.50 for Cd showing potential carcinogenicity. It was concluded that as the organic amendments have the widest application in vegetables, it should be prudent to avoid their contamination and mobilization in plant-soil ecosystems to protect public health perspectives.