Evaluating Mercury Pollution in the Blood of Free-Roaming Dogs in Gorgan City, Golestan Province

Background: Mercury is a dangerous biological pollutant that contaminates food chains and enters the bodies of animals.Since free-roaming dogs are omnivorous and cover a large geographical area, this study measured mercury levels in the blood of freeroaming dogs in Gorgan City.Methods: After recording the sampled dogs' characteristics, blood samples were collected, and mercury concentrations were measured using Coupled Plasma Mass Spectrometry (ICP-MS). Results:The mean mercury concentration in the blood samples was 24.9 g/L.Statistical analysis revealed no significant differences in mercury concentrations between male and female dogs (P = 0.669) or across different age groups (P = 0.486).Conclusion: These findings underscore the presence of mercury pollution in Gorgan City, as blood mercury levels can indicate recent environmental contamination.The average mercury concentration in various areas of the city was below the toxic threshold of 105 g/L.However, even low levels of mercury exposure can be toxic to mammals.Since industrial and hospital waste are recognized as major sources of mercury, it is recommended that these wastes be treated before being released into the environment.The research also indicated that domestic dogs could serve as valuable bioindicators for monitoring environmental contamination by hazardous metals, such as mercury.