BACKGROUND: Many toxic elements enter human food in different ways by various industries which can put people's lives in danger. Heavy metals can be rarely removed from the body after absorption and deposition in tissues, which can lead to diseases and complications in the body. Mercury is one of the heavy metals that can posion people after consumption of contaminated seafood. The measurement of pollutants such as mercury that present in aquatic animals and environment is one of challenges for humans.OBJECTIVES: This study aims to measure the amount of mercury accumulation in the edible tissue of whiteleg shrimp (Litopenaeus vannamei) found in farms of Bushehr Province in Iran.METHODS: In this research, 70 whiteleg shrimps were collected during four sampling stages in July, August, September and October for two consecutive years. Total mercury level was measured by the cold vapor method.RESULTS: The level of mercury was 0-0.009 mg/kg of body weight, while the recommended limit for mercury is 0.1 mg/kg according to the WHO. The microscopic study on tissue sections did not show any histopathological changes.CONCLUSIONS: The mercury level in the edible tissue of whiteleg shrimps in Bushehr province is much lower than the recommded level and does not pose any danger to residents and consumers.

Introduction: The study examined the concentration of total mercury and correlation coefficients between fish size or FCF (condition factor) and the content of Hg in muscle tissue of six freshwater fish: bream (Abramis brama L.), roach (Rutilus rutilus L.), whitefish (Coregonus lavaretus L.), vendace (Coregonus albula L.), perch (Perca fluviatilis L.), and pike (Esox lucius L.). Material and Methods: The fish were caught from the Lake Pluszne located in the Olsztyn Lake District (Poland). Mercury was analysed by atomic absorption spectrometry using Milestone DMA-80 (with dual-cell). Results: The content of the element in the muscles of the examined fish was as follows: pike (0.197 mg/kg) ≈ perch (0.173 mg/kg) > vendace (0.114 mg/kg) ≈ roach (0.095 mg/kg) and roach ≈ whitefish (0.065 mg/kg), and whitefish ≈ bream (0.042 mg/kg) (p ≤ 0.05). In all cases, the content of mercury correlated positively with the body weight and total length of the fish. Only the correlation coefficients between mercury concentration and weight or length of bream were slightly higher (0.979 and 0.977 respectively, p ≤ 0.001). The length and weight relationship of the fish was also determined. Conclusion: The results showed that the levels of mercury were lower than the maximum acceptable limit established by the Commission Regulation (EC) No 629/2008 of 2 July 2008. Thus, they are safe from consumer health point of view.

Introduction: Hard antlers of deer are unique bioindicators of environmental metal pollutions, but sampling methods presented in the literature are inconsistent. Due to the specific growth pattern of antlers and their histological structure, sampling methods described in the literature were reviewed, the suitability of using mixed samples of both antler layers as element bioindicators was assessed, and the codified method of antler sampling used for bioindication was described. Material and Methods: Lead, cadmium, mercury, arsenic, copper, zinc, and iron in trabecular and cortical parts of hard antlers of red deer (Cervus elaphus) were determined using different methods of atomic absorption spectrometry (depending on the element). Results: Mean mercury content in trabecular bone (0.010 ±0.018 mg/kg) was 5 times higher than in cortical bone (0.002 ±0.003 mg/kg). Mean iron concentration was approximately 15 times higher in trabecular (239.83 ±130.15 mg/kg) than in cortical bone (16.17 ±16.44 mg/kg). Concentrations of other analysed elements did not differ statistically between antler layers. Conclusion: In mixed antler samples, concentrations of mercury and iron depend on the particular antler layer contents. This therefore warrants caution when comparing results across studies and specification of the sampling methodology of antlers is highly recommended.

Introduction: The study examined the concentration of total mercury and correlation coefficients between fish size or FCF (condition factor) and the content of Hg in muscle tissue of six freshwater fish: bream (Abramis brama L.), roach (Rutilus rutilus L.), whitefish (Coregonus lavaretus L.), vendace (Coregonus albula L.), perch (Perca fluviatilis L.), and pike (Esox lucius L.). Material and Methods: The fish were caught from the Lake Pluszne located in the Olsztyn Lake District (Poland). Mercury was analysed by atomic absorption spectrometry using Milestone DMA-80 (with dual-cell). Results: The content of the element in the muscles of the examined fish was as follows: pike (0.197 mg/kg) ≈ perch (0.173 mg/kg) > vendace (0.114 mg/kg) ≈ roach (0.095 mg/kg) and roach ≈ whitefish (0.065 mg/kg), and whitefish ≈ bream (0.042 mg/kg) (p ≤ 0.05). In all cases, the content of mercury correlated positively with the body weight and total length of the fish. Only the correlation coefficients between mercury concentration and weight or length of bream were slightly higher (0.979 and 0.977 respectively, p ≤ 0.001). The length and weight relationship of the fish was also determined. Conclusion: The results showed that the levels of mercury were lower than the maximum acceptable limit established by the Commission Regulation (EC) No 629/2008 of 2 July 2008. Thus, they are safe from consumer health point of view.

Meat contamination is a problem that must be addressed since it can affect consumers' health. Standard acceptable limits for heavy metals in meat and organs have been established by many international organizations. Livestock including sheep, cattle, camels, and goats side by side with other poultry species are the most significant sources of meat for protein. Heavy metal contamination in animal products may be harmful to people's health. The earth's crust naturally contains heavy metals, but uncontrolled human activity has significantly changed their geochemical cycles and biological equilibrium. This causes a buildup of metals in animal tissue that contain secondary metabolites, which gives rise to a specific pharmacological action. Humans can have negative health effects from prolonged exposure to heavy metals as lead, cadmium, arsenic, and mercury. This review showed that most of the studies conducted in different countries on heavy metals were mostly in red meat, and the research was few in the cases of domesticated birds and very rare in game birds, although it is considered a good example for investigating heavy metals in the environment

In the aquatic environment, pollution with heavy metals is a major issue. Some of them are essential heavy metals because they play biological roles for aquatic organisms. Other heavy metals, however, are regarded as dangerous even at low concentrations. Heavy metal levels that are harmful may be caused by industrial, mining, and agricultural operations. Water contamination and changes to the physicochemical properties of the aquatic environment will result from this. The harmful toxic consequences of this pollution on fish raise questions about its possible impacts on human health. The most prevalent heavy metals are arsenic, cadmium, lead, and mercury, which are systemic toxicants and have an impact on human health. These metals are classified as carcinogens by the United States Environmental Protection Agency and the international agency for research on cancer because they cause organ damage even at low exposure levels. This review was created to contribute to the understanding of the environmental impact, toxicology, and consequences of heavy metals on fish.