Abstract
This article focuses on the toxic element chromium (Cr) in wastewater, its incorporation into soil plant systems, and its relevant toxicity in the food chain as assessed by a health risk assessment from dietary intake. The Nili Ravi buffalo is an important cattle inhabiting Sargodha, Punjab, Pakistan, and forage crops grown on soils contaminated with Cr might cause toxicity in the food chain by local inhabitants eating meat. The soil, forage and animal blood samples were collected from five different locations in Tehsil Sahiwal (Chak Dhool, Bagabalocha, Chandia, Dhool Bala and Kakrani) twice at six-month intervals. A total of 30 samples from each ecological zone were collected from the soil and forage crops (Zea mays, Sorghum bicolor, Trifolium alexandrinum). The samples from zone-V and zone-IV showed the maximum concentration of Cr because these areas receive highly contaminated water for irrigation. The Cr was greater than the permissible limits. Environmental indices for all samples ranged below 1. The bioaccumulation and pollution load of Cr in soil and forage crops due to wastewater irrigation can contaminate the whole food chain via the soil, forages and animals. The health risk index (HRI) and a high value of enrichment factor were found for Cr in some sites. The Cr concentration was higher during the summer season than winter. Fodder crops with different concentrations and an elevated level of Cr were observed in maize. Attention should be paid when wastewater is used for fodder crop irrigation and its potential risks to human health following dairy product (milk, meat) entry into the food chain.