Are aquatic life sustainable with current policies? Microbial pollution in swimming seasons: A 12-year retrospective study on the bathing waters of Sinop, Turkey

The study aimed to examine the characteristics of the beaches of Sinop Province, monitor the faecal pollution trend in the years 2011 – 2022, examine its causes, comparison with studies conducted in Turkey, awareness of people regarding pollution in the seas, and the compatibility of the classification system of the Ministry of Health with the WHO. A total of 2503 samples collected from 29 beaches in Sinop Province during the years 2011 – 2022 were evaluated. Descriptive statistics like Mann-Whitney U and Kruskal-Wallis tests were used to summarize the data and concordance analyses was used to compare the groups. The highest microbial pollution in beach water was observed in 2020. When the source of pollution was examined for the cause, the most evident (40.0 %) was “pollution from wild animals”. When the microbial quality assessment of the World Health Organization for recreational waters and the assessment of the Ministry of Health were examined, it was found that there was a low-medium level of agreement. In some beaches of Sinop Province, certain indicators of bacteriological pollution have reached poor levels within twenty four day period from 2011 to 2022. In the follow-up of bathing waters, classification and measurements should be based on differences between provinces, prioritizing public health.