Abstract
The toxicity studies using soil invertebrates are good tools for assessing the soil quality of a region. In this study the toxicity assessment of industrial soils using Eisenia andrei was done using field soils and artificial soils spiked with zinc (Zn) and cadmium (Cd). Considering field soils, the soils near the industrial region showed higher toxicity than those away from the region and in spiked soils, the toxicity followed the order Zn < Cd < Zn + Cd. The Mixed Toxicity Index (MTI) revealed an antagonistic response between Zn and Cd (MTI < 0) which points out the influence of one element in reducing the toxicity of the other. The biomass showed the highest reduction in zone 1 soils and Zn + Cd treated soils. A similar trend was noted for the hatchability of cocoons. The bioconcentration studies showed that bioaccumulation has not occurred in field soils and spiked soils. However, despite the bioaccumulation, there were certain responses at short-term (acute) and long-term (chronic) treatments. The study points out the single and combined impact of soil toxicants in the home garden soils on the overall health and survival of invertebrates and also the possibility of reducing those effects using various nutrients in the soil ecosystems.