Monitoring of individual indicators of safety and quality of water and fish of Khadzhibey estuary

Abstract

Water significantly influences the quality and safety of fish because it is the environment for the life and cultivation of fish. A study of hydrochemical and microbiological indicators of the water of Khadzhibey estuary was conducted; the content of heavy metals in it was determined. In the Khadzhibey estuary, from 2022 to 2023, the water acidity indicator was stable, did not exceed the established hygienic standards for fish farms, and was within the range of 7.6 ± 0.4–8.4 ± 0.3 mg/L, which completely meets the requirements for fish farming. The maximum salinity in the estuary is observed in summer and is 15 % higher compared to winter and spring indicators. The water type of the estuary is mixed with moderate mineralization. It was established that the zinc content in water samples from the estuary exceeds the maximum permissible concentration by 2.6 %. The content of Cadmium, Lead, Copper, and Mercury is constant and does not exceed the maximum allowable concentration for fish farms. An increase in zinc content in water is a stress factor and affects the quality of fish meat. The research results showed that the content of mesophilic aerobic and facultative anaerobic organisms does not exceed the maximum permissible level in muscle tissue cultures of common carp and round bull caught by commercial fishing from the Khadzhibey estuary. Escherichia coli bacteria, Staphylococcus aureus, Listeria monocytogenes, and pathogenic microorganisms were not detected in the samples of the fish subject to the study. According to the microbiological indicators of water and fish, common carp and Round goby caught by industrial fishing in the Khadzhibey estuary are safe and allowed for further consumption by humans and animals.