Detection of Parasitic Contamination and Coliform Bacteria in vegetables from Ongkharak market in Nakhon Nayok province

Abstract

Parasitic infectious diseases are still a public health problem in Thailand. In addition to being infected with parasites due to consumption of fresh vegetables, consumers were also at risk of getting coliform bacteria. Therefore, this research aimed to determine parasitic contamination and contamination of coliform bacteria in fresh vegetables by using a sedimentation technique and the SI-2 coliform bacteria test kit. The selection of vegetable samples in the research focused primarily on popular vegetables to be eaten fresh and readily available in the local wet markets. Five varieties of fresh vegetables, 9 samples each, including coriander, spring onion, lettuce, peppermint, and celery were obtained from Ongkharak Market, Nakhon Nayok province. Laboratory results found 79.8% and 46.6% of intestinal protozoa and helminths, respectively. The most parasitic contamination was found in 100% of mint, followed by 88.8% and 55.5% of spring onion and coriander, respectively. The most common parasites were Cyclospora cayetanensis (37.7%), followed by Ascaris lumbricoides, Giardia lamblia and Blastocystis hominis, which were found as the same proportion of 17.7%. Contamination of coliform bacteria was found in 64.4% of sample vegetables. The highest contamination was found in coriander, lettuce and celery at 77.7%, followed by spring onion at 66.6%. The detection of parasites and coliform bacteria contamination in each type of fresh vegetables had no statistically significant difference (p=0.237, p=0.085). The results of the study demonstrated that the contamination of parasites and coliform bacteria in fresh vegetables has affected the health of consumers. Therefore, relevant health authorities should educate people on proper washing of vegetables before consumption.