Stress mitigation and phyto-accumulation of iron in different leafy vegetables irrigated with treated municipal solid waste and health risk repercussions in human

Abstract Heavy metal pollution of soil is a growing environmental issue due to irrigation with untreated municipal and industrial waste-water, vehicle emissions, and other activities in Pakistan. Agricultural and urban soil, being the prime part of the environment, acts as a chief reservoir or sink of pollutants, including heavy metals, in the food chain. Interest in using urban waste composts as amendments in urban agriculture is growing nowadays. Concerns about the potential transference of pollutants present in urban waste to the food chain are very relevant when they are recycled for food or animal feed production. To carry out the present study, soil and plant samples were collected from the site. Then, to measure the iron (Fe) contents in the edible portion of vegetables along with selected soil physicochemical parameters, wet acid digestion with a nitric acid/perchloric acid mixture was performed. The digested samples and all the supernatants were analyzed for heavy metals using the Flame Atomic Absorption Spectrophotometer (FAAS). Heavy metal (Fe) shows a significant build-up in the vegetables as when grown on the municipal solid waste amended soil. Various indices such as PLI, BCF, DIM, HRI were calculated, and results showed that PLI was above 1, indicating that metal was causing pollution in selected samples, while the values of BCF, DIM, and HRI were within the permissible range.