Contamination of soil and plants with potentially toxic elements irrigated with mixed industrial effluent and its impact on the environment

For productive utilisation of effluent-contaminated agricultural land, mobilisation and statistical analysis of potentially toxic elements in soil and plants of fields irrigated with mixed industrial effluent have been undertaken. Total Fe, Mn, Zn, Cu, Pb, Ni and Cr have been estimated in soil and plant species of contaminated and noncontaminated sites. 18 plants species and 18 root adjacent soil samples from contaminated Kalipur area and 11 plants species and 11 root adjacent soil samples from uncontaminated Madhabpur area comprising major crops, vegetables and weeds have been included in the study. It is revealed that Hibiscus esculentus, Lycopersicon esculentum and Luffa acutangula growing in effluent-contaminated field show mobilisation ratio < 0.5 for most of the PTE (Potentially Toxic Elements) like Cu, Pb, Ni, Cr and Cd and normal morphology. Surprisingly, weeds in particular, show high mobilization ratio > 0.5 and simultaneously exhibit healthy gigantic morphology at the early flowering stage. Coriandrum sativum, Raphhanus sativus, Solanum melongena, Spinacea oleracea, Oryza sativum, Brassica oleracea showed mobilization ratio > 0.5 but maintained normal growth. Based on mobilization ratio and external morphology, we suggest the cultivation of plants H. esculentus, L. acutangula, L. esculentum in land irrigated with industrial effluent. The highest and second highest enrichment factor (EFpp) was found for Cd and Pb, respectively. Pearson's correlation coefficient indicated that the metal level in soil is not the main factor governing metal uptake. This study will help in selecting plant species for cultivation in contaminated fields.