Do the total mercury concentrations detected in fish from Czech ponds represent a risk for consumers?

Abstract

Mercury is one of the important pollutants of the environment. Therefore, it’s necessary to monitor quantity of mercury especially in aquatic ecosystems. The main goal of the presented study was to compare the content of total mercury in tissues of fish coming from the Czech Republic, an important carp exporter, with focus on comparison of mercury content between 3 different ponds, its comparison between different fish species and between different tissues of the same species, and estimation whether the mercury content in tissues meets the limit given in the Commission Regulation (EC) No. 1881/2006 or not. Total mercury concentration was measured in 90 fish specimen sampled from three ponds (Velky Kocelovicky, Mysliv and Zehunsky) in autumn 2018. The values of total mercury in fish tissues was measured by atomic absorption spectrometry. The content of total mercury in the tissues decreased as follows: muscle > liver > gonads > scales. The highest average content of total mercury in muscle was 0.1517 ± 0.0176 mg/kg coming from pike caught in Velky Kocelovicky pond. In contrast, the lowest average content of total mercury in muscle 0.0036 ± 0.0003 mg/kg was found in carp tissue coming from the locality of Zehunsky pond. We confirmed that the predatory fish are more exposed to mercury than non-predatory fish. None of the monitored localities exceeded the set regulatory limit. Thus, our study shows that fish coming from these ponds are safe in terms of total mercury content.

Total mercury content in selected tissues of common carp (Cyprinus carpio) pond farmed in the Czech Republic

“…The results found suggest that mercury does not pose a risk to consumers of these commercially farmed fish. Mercury contents in market carp are found to be below the limit in the long term in the Czech ponds in South Bohemia (Král and Svobodová 2020), in West and South of Bohemia (Sehonova et al 2022), in reservoirs from Bohemian-Moravian Highlands (Vičarová et al 2016) and also in carp from Slovak surface waters (Kimáková et al 2018). The results are in accordance with the findings from the studies by Sehonova et al (2022) and Svobodová et al (1999) reporting that the mercury content in carp decreases in the following order: muscles > caudal kidney > liver > spleen > brain/gonads > scales.…”

“…The mercury content is highly variable in fish bodies, depending on many factors such as the fish species, its position in the food chain, contamination of the sampling site (Marsalek et al 2005;Novotna et al 2020;Novotna Kruzikova et al 2022) or the form of mercury. Total mercury (THg) content differs in individual tissues (Sehonova et al 2022) and the THg liver/muscle index can be used for the assessment of mercury contamination of the aquatic environment (Havelkova et al 2008;Kružíková et al 2013). The consumption of fish is the most common route of mercury exposure for most of the world's population.…”

Risks to Human Health from the Consumption of Water from Aquifers in Gold Mining Areas in the Coastal Region of Ecuador

“…The first influencing factor is the concentration of available mercury, and the possible presence of other contaminants, but the age of the fish is also a factor since mercury accumulates inside their tissues according to their feeding habits. In particular, an increased presence of mercury was found in predatory fish [42].…”