Ecological risk assessment of zinc metal in different varieties of wheat (Triticum aestivum L.) irrigated with wastewater regimes: Assessing the public health risk

Concerns over water contamination have prompted a review of the hazards posed by waterborne contaminants. The use of wastewater irrigated wheat grains and the rate of water irrigation to the crops is a crucial aspect that includes comprehensive approach, covering both human and environmental health. Although, water usage enormously depends on spatial factor such as geographic location, but long term consumption of grains grown in contaminated soil may surpass permissible intake of essential elements. Therefore, this study was conducted in randomly selected districts of Punjab, Pakistan to assess the Zinc (Zn) content in water, soil and in various parts of cereal crop wheat (Triticum aestivum L.) during two consecutive growing seasons. The present study estimated significant concentration of Zn range between 0.83 µg/l to 0.93 µg/l in various water regimes, which was minimum in groundwater. Therefore, highest Zn concentration in IWW irrigated soil was recorded during the second cropping season with value of 42.33 mg/kg, however, PLI and BAF were estimated less than 1. The Zn concentration in roots, shoot and grain was ranging in decreasing range of 30.70–35.99 mg/kg, 23.96–25–53 mg/kg and 3.32–7.49 mg/kg respectively. From current study we can conclude that, usage of wastewater in specific proportion to freshwater did not cause any harmful effects and therefore it’s safe to reduce chemical fertilizer cost. However, further investigations are recommended to revealed physiological and molecular aspects.