Soils and Vegetables Enrichment with Heavy Metals from Application of Sewage Water

Abstract

Application of waste water for irrigation purposes has increased over the past years due to the shortage of water. This waste water contains high amounts of heavy metals which are very toxic. The objectives of this study were To analyze the heavy metals in selected area of Lahore, To determine the concentration of metals in soil and different parts of plants (Leaves and fruit) and To determine the distribution of heavy metals into different soil strata The present study revealed that heavy metal content was above the toxicity level in leafy vegetables grown in the area of Lahore. This study showed that among the different tested plant species, the amount of heavy metals was more in leaves than fruits. Plants whose fruits grow below the soil showed higher concentration of heavy metals while other showed less concentration whose edible portion was above the ground level. The concentration of heavy metals in upper layer of soil (0 -15 cm) is higher than the lower layer (15-30 cm). The reason behind is that the upper layer was receiving sewage water permanently while the penetration of sewage water below 15 cm was less. That’s why the heavy metals accumulated more in the upper layer of the soil than the lower layer.

Keywords: heavy metals, plants, soil strata, toxic, waste water