RISK ASSESSMENT OF HEAVY METAL AND MICROBIAL CONTAMINATION IN COMMERCIALLY AVAILABLE SALAD VEGETABLES OF FAISALABAD, PAKISTAN

Vegetables are vital for an efficient functioning of human's body as they build a major constituent of human diet in each family. Irrigation with polluted waters and poor post harvesting management in olericulture are described as the major sources of heavy metal contamination and bacterial infection in vegetables. Intensive use of pesticides may result in enhancing or reducing the above mentioned hazards. It is very important to regularly assess the market vegetables to determine if they are safe for consumption in raw or cooked form. The major focus of current study was to analyze the quality of four highly consumed salad vegetables carrot (Daucus carota) tomato (Solanum lycopersicum), green chilli (Capsicum annuum) and cucumber ( Cucumis sativus), for their safe utilization as food. This study was conducted to evaluate the presence of the most reported heavy metals ( cadmium, lead and chromium) and microbial contamination like Escherichia coli in above mentioned vegetables. Samples were collected from three types of commercial vegetable markets in Faisalabad: local vegetable markets (wholesale market), supermarkets and street venders. It was observed that the range of cadmium (Cd), chromium (Cr) and lead (Pb) in vegetables were 1.23-7.23, 1.11-5.33 and 1.22-7.11 mu g g(-1), respectively. However, the detected mean values of all heavy metals were less than that of acceptable limits by the World Health Organization (WHO). Furthermore, E. coli contamination was observed in all the samples of vegetables from roadside retailers but in only few samples from supermarket, however, all the levels were under permissible limits. So, our results showed that these vegetables were safe for human consumption.