A Microbiological Risk Assessment At The Fresh Produce Wholesale Market In Doha

Abstract

Food contamination is a challenging problem in many developing countries, like Qatar where the majority of food is imported. The wholesale fresh produce market (WSFPM) in Doha is considered as the major produce market from which the supermarkets, restaurants, and people obtain their produce. The WSFPM is an open-air market located in close proximity to the fish market, slaughterhouse, and industrial area. At the moment, there is no information available on the prevalence of microorganism is in and the impact of the surrounding markets on the microbial quality of produce sold at this market. Therefore, this study was carried out to 1) determine the source of the microbiological hazards associated with sanitary conditions at the WSFPM; 2) evaluate the different sources contributing to the microbial hazards; 3) assess the workers’ level of food safety knowledge and their behavior in handling produce; and 4) conduct a microbial risk assessment to determine the potential risks associated with fresh produce consumption. Different produce (e.g. cucumber, green onion, lettuce, tomato, and parsley), soil, air, and surface swabs samples were collected from WSFPM and the surrounding areas between July 2016 and June 2017. Selective media were used to determine the presence of pathogenic E. coli, Listeria spp., Staphylococcus spp., and Salmonella spp. The presumptive colonies were isolated and identified using MALDI-TOF and molecular techniques. The workers who were in direct contact with the produce were.

examined in the winter of 2015. During the survey application, hand-swab samples were also collected. The risk of getting sick through consumption of green onion, cucumber, tomato, green pepper, and romaine lettuce contaminated with select microorganisms was calculated using the sQMRA model. The microbial counts of produce samples determined, indicated that the samples were heavily contaminated (> 4 Log10 CFU/g) with Bacillus, Enterococcus faecium, E. coli, Klebsiella pneumoniae, Pseudomonas, Enterobacter, Alternaria, Aspergillus, and Penicillium species. There were no pathogenic bacteria identified in any of the sample tested in this study. The same trend was also observed in soil, air, and surface samples. It was surprising to find out that none of the workers had any training on safe produce handling practices. Almost 70% of them claimed to wash their hands 4-5 times per day. However, the hand-swab samples’ results verified that the hygiene practices applied by the handlers are not sufficient since pathogens such as Klebsiella and Staphylococcus were identified. These results demonstrated that there was an urgent need to organize an educational training to familiarize the workers on food safety and hygiene practices. The mean annual probability of getting sick after consuming the raw produce contaminated by coliforms ranged between 0.27 and 0.46, indicating that attention needs to be paid specifically on 1) improving the sanitary conditions at this target market, 2) educating the produce handlers and consumers on safe food handling practices, and 3) applying appropriate mitigation measures, such as periodical monitoring and adopting a risk-oriented approach in order to avoid any costly produce outbreak.