HEAVY METAL TOXICITY AND HUMAN HEALTH RISK SURVEILLANCES OF WASTEWATER IRRIGATED VEGETABLES IN LAHORE DISTRICT, PAKISTAN

The concentration levels of cadmium (Cd), chromium (Cr) and lead (Pb) in wastewater drains (Gulshan Ravi, Shadbagh and Outfall), soil and wastewater irrigated vegetables (Brassica campestris L. Brassica oleracea capitata, Brassica rapa L. Solanum tuberosum L.) from Lahore District, Pakistan were assessed using atomic absorption spectrophotometer. The general trend for heavy metal level in soil samples was Pb> Cd> Cr and within the permissible limits described by European Union. The contamination status of three drains was found high and not considered good for irrigation purpose. The Pb and Cd concentration was higher than the limits (0.1mg/kg and 0.05mg/kg) set by FAO (Food and Agriculture Organization) and WHO (World Health Organization) in all vegetable samples and maximum Pb was in leafy vegetable (Brassica campestris L.) found higher than the Indian standards. Maximum metal transfer factor (MTF) was recorded for Cd in Brassica rapa L. (0.947). Daily intake metal for Pb was maximum and above the WHO permissible limits by the consumption of Brassica campestris L. and Solanum tuberosum L. Health risk assessment of Cd, Cr and Pb by the consumption of wastewater irrigated vegetables revealed least health risk (<= 1), except for Cd having (HRI >= 0.1) that could be the source of potential health risk for the consumers community.