Muhandisī-i Bihdāsht-i Muḥīṭ (Mar 2016)
Performance Evaluation of Alternative Disinfectants in Reducing Microbial Contamination of Vegetables Supplied from City of Kermanshah
Abstract
Background: In recent decades, due to the scarcity of fresh water resources and high costs of wastewater treatment, cases of irrigation of cultivation of vegetables using raw sewage and polluted effluents or the use of human and animal faeces have been reported. Vegetables are important sources of exposure of human pathogenic pathogens such as fecal coliforms. The aim of this study was to evaluate the performance of three different disinfectant on several kinds of vegetables that would normally be released in Kermanshah. Methods: In this cross sectional study, 180 randomly selected vegetable samples were collected from mobile and fixed stores of vegetables in Kermanshah. Then, to evaluate the effectiveness of disinfectants in eliminating microbial samples, three types of disinfectants containing active ingredient Benzalconium chloride, were studied. Heterotrophic plate count (HPC) surface culture method, coliform count (VRBA) Violet Red Bile Agar purplate method and Yeast Glucose Chloramphemicole Agar (YGCA) surface culture method was used in order to count the microbial load. Results: The findings of this study suggest that the overall average performance of all three disinfectants was less than 75% and most disinfection efficiency was observed in two-fold concentrations of proposed by manufacturer. Based on the analysis of the resulting data, disinfectants examined in this study had an average efficiency of 76.13% for the removal of coliforms as an indicator of gram-negative bacteria and 100% for the removal of Streptococcus bacteria as indicators gram positive bacteria. Conclusion: Disinfection can not solely guarantees the maintaining the health of the consumer. We could have declared that recommended disinfection conditions and existing facilities can effectively reduce the microbial load of vegetables. However, preparing vegetables from safe and ensure proper burial are recommended. Moreover, consuming the raw vegetables in sensitive seasons and precarious conditions should be avoided.
