The present study was conducted to appraise the human health risk due to dietary intake of heavy metals contaminated vegetables viz., cabbage (Brassica oleracea var. capitata), cauliflower (Brassica oleracea var. botrytis) and spinach, (Spinacia oleracea) grown in the municipal wastewater irrigated soil in the proximity of sewage treatment plant (STP), Jagjeetpur, Haridwar. The results showed that Cd, Fe and Mn concentrations in B. oleracea var. capitata, B. oleracea var. botrytis and S. oleracea were found beyond the safe limit of the Indian and WHO/ FAO standards for heavy metals in the vegetables. The contamination factor of these heavy metals in the soil was recorded in the order of Fe > Mn > Zn > Cu > Cr > Cd after irrigation of municipal wastewater. The higher values of metal pollution index in different vegetables as B. oleracea var. capitata (14.82; B. oleracea var. botrytis (10.48) and S. oleracea (12.59) showed more health risk index for Cd, Fe and Mn in these vegetables cultivated in the wastewater irrigated soil. Therefore, dietary intake of these heavy metals contaminated vegetables may pose a significant threat to the human health. However, cauliflower contained less heavy metal as compared to the cabbage and spinach, but health risk was more due to higher role in the diet. Even though there were low concentrations of heavy metals in the municipal wastewater used for the irrigation, but long term use of the municipal wastewater may cause gradual buildup of heavy metals in the vegetables grown in the municipal wastewater irrigated soil and leads to health risk of consumers due to intake of heavy metals contaminated vegetables.
©2018 Agriculture and Environmental Science Academy
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INTRODUCTIONWastewater irrigation is a collective realism in three-fourth of the cities in Asia, Africa and Latin America. Wastewater conveys substantial amounts of trace toxic metals (Pescod 1992;Yadav et al., 2002). Wastewater irrigation is known to have its significant impact to the heavy metal content of soils (Mapanda et al., 2005;Nan et al., 2002). This charging of heavy metals often clues to degradation of soil health and adulteration of food chain mainly through the vegetables grownup on such soils (Rattan et al., 2002). Most municipal farmers in India use wastewater rich in harmful heavy metals alike cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), lead (Pb) and zinc (Zn) and biological negotiators such as pathogenic bacteria, coliform bacteria fungi, protozoans and nematodes etc. and this poses serious health pressures, such as a risk of biomagnifications of heavy metals and conveying intestinal nematodes and bacterial infections especially to consumers and farm hands (Manios et al., 2006;Zhang et al., 2008;Pathak et al., 2011;Kumar et al., 2015Kumar et al., , 2017. Heavy metals are usually not removed even after the treatment of wastewater at sewage treatment plants, and thus cause threat of heavy metal adulteration of the soil and consequently to the food chain (Fytianos...