Abstract:
The study of the survey of food safety which is the risk factor of Cholangiocarcinoma (Bile duct cancer) in Surin province aimed to survey the prevalence of liver fluke Opisthorchis viverrini metacercaria in freshwater fish and products from freshwater fish with scales, and survey the nitrate and nitrite contamination in fermented meat and fish with scales. The target areas were Mool River in Tha-Tum and Chumphom-Buri District including Huai-Saneng and Am-Bpeun Reservoir in Muang Surin District. This study was survey research, by random sampling of freshwater fish and products from freshwater fish with scales which were at risk for infected which Opisthorchis viverrini metacercaria. Then analyze by using the standard pepsin digestion method. Moreover, random sampling of fermented meat and fish with scales which were at risk for contamination with nitrate and nitrite. Then analyze by using the spectrophotometric method. Statistical analysis was calculated in terms of prevalence rate, frequency and percentage.
The results of this study revealed that, the overall 21 kinds of freshwater fish which were responsible for 170 samples, Opisthorchis viverrini metacercaria were not found. However, we found metacercaria of minute intestinal trematode. The overall prevalence of infection was 32.4 % (n=170). The area, which was found the highest prevalence, was Chumphom-Buri accounting for 47.3 % (n=55). The analysis results of products from freshwater fish with scales for 9 kinds showed 26 infected fish from total 111 examined fish. Prevalence of infection was 23.4 %. We found 4 species of minute intestinal trematode as follows, Hoplorchis toichui, Hoplorchis pumilio, Hoplorchoides sp, and Centrocestus coninus. The highest prevalence of infection rate was Hoplorchis toichui. The results of nitrate and nitrite contamination analysis in fermented meat and fish with scales revealed that only sweet dried fish was contaminated with nitrate, which was higher than the standard values that the Ministry of public health allowed to use in foods. It contained 1,925.99 mg/kg of nitrate. This was responsible for 1% of total 98 samples. However, the surveillance of food safety and assessment of liver fluke epidemiology should be monitored to be the current situation.