Heavy metals in soils and forage grasses irrigated with Vieira River water, Montes Claros, Brazil, contaminated with sewage wastewater

• Published in: Revista ambiente & água 2020, Vol.15 (2), p.1-11
• Main Authors: Reis, Matheus Mendes, Santos, Leonardo David Tuffi, Silva, Ariovaldo José da, Pinho, Gevany Paulino de, Rocha, Leonardo Michel
• Format: Article
• Language: English
• Subjects: Agricultural pollution; Anthropogenic factors; Arsenic; Chromium; Contamination; Copper; Downstream; ecological risk; Ecology; ENGINEERING, ENVIRONMENTAL; Environmental risk; Food chains; Food contamination & poisoning; Forage; geoaccumulation index; Grasses; Heavy metal content; Heavy metals; Irrigated areas; Irrigation; Irrigation water; Laboratories; Lead; Nickel; Osmium; Pollutant load; Pollution; Pollution index; Pollution load; Risk analysis; Risk factors; River water; Rivers; Sediment pollution; Sewage; Soil; Soil contamination; Soil pollution; Soils; Transfer factor; Wastewater; Wastewater discharges; Wastewater pollution; water contaminated; Water pollution; Water treatment; Zinc
• ISSN: 1980-993X; 1980-993X
• DOI: 10.4136/ambi-agua.2440

 There is great concern with soil and plant contamination by heavy metals due to the use of polluted water in agricultural irrigation. In this study, areas irrigated with Vieira River water were evaluated as to contamination by As, Cr, Cu, Ni, Pb and Zn. The Vieira River receives effluent from Montes Claros city, state of Minas Gerais, Brazil. To do so, two irrigated areas were selected, one upstream and one downstream of the Montes Claros city. Wastewater discharge increased the concentration of As and Ni in the water of Vieira River, and consequently, of As, Cr, Cu, Ni, Pb and Zn in the soil and of As and Zn in forage grasses. However, the content of heavy metals in the soil did not exceed the internationally recommended limits. Pollution load index (PLI) and contamination factor (CF) indicated the existence of pollution and moderate contamination in downstream soils of the city of Montes Claros. Potential ecological risk index (RI) and ecological risk factor (Er) indicated a low ecological risk, but these indicators were higher in downstream soils of Montes Claros. Arsenic (As) was the only heavy metal that featured a transfer factor (TF) higher than the widespread values found in literature and positive geoaccumulation index (Igeo), indicative of anthropogenic pollution.