Determination of Mercury, Methylmercury and Selenium Concentrations in Elasmobranch Meat: Fish Consumption Safety

Abstract

This study measures total mercury (THg), methylmercury (MeHg) and selenium (Se) concentrations in elasmobranch fish from an Italian market with the aim of evaluating the risk-benefit associated with their consumption, using estimated weekly intake (EWI), permissible safety level (MeHgPSL), selenium health benefit value (HBVSe) and monthly consumption rate limit (CRmm) for each species. THg and Se were analysed by atomic absorption spectrometry, while MeHg was determined by HrGc/Ms. THg and MeHg concentrations ranged from 0.61 to 1.25 μg g−1 w.w. and from 0.57 to 0.97 μg g−1 w.w., respectively, whereas Se levels were 0.49–0.65 μg g−1 w.w. In most samples European Community limits for THg were surpassed, while for MeHg none of the fish had levels above the limit adopted by FAO/WHO. EWIs for THg and MeHg in many cases were above the provisional tolerable weekly intakes (PTWIs). MeHgPSL estimate showed that fish should contain approximately 50% of the concentration measured to avoid exceeding the PTWI. Nevertheless, the HBVSe index indicated that solely skates were safe for human consumption (HBVSe = 3.57–6.22). Our results highlight the importance of a constant monitoring of THg and MeHg level in fish, especially in apex predators, to avoid the risk of overexposure for consumers.

Analysis of the Mercury Content in Fish for Human Consumption in Poland

“…In Poland, the consumption of tuna and king mackerel, among others, is not recommended for pregnant and lactating women and children [ 66 ]. Research results highlight the importance of continuous monitoring of total mercury and MeHg levels in fish, especially predatory fish, to avoid the risk of overexposure in the population [ 15 ].…”

“…Mercury accumulates in the trophic chain, especially at the top of the chain in predatory fish [ 16 , 17 ]. In fish tissues, MeHg concentrations can reach up to 90% of the total content of this metal [ 15 , 18 ]. MeHg is mainly deposited in the liver, kidneys and brain of fish and in muscle tissue consumed by humans.…”

Sustainable or Not? Insights on the Consumption of Animal Products in Poland

“…However, the positive effect of fish on the human body depends on the species of fish and the water (area) the fish originate from. They may contain too many harmful substances, e.g., arsenic [ 17 ], mercury [ 87 ] or selenium [ 88 ], and thus are harmful to human health. This is especially important for women who are or who are planning to be pregnant [ 89 ].…”

Invasive Round Goby (Neogobius melanostomus) Fish from the Southern Baltic as a Source of Arsenic and Selenium—Food Safety Aspects

“…Conversely, excessive exposure to Se can facilitate the development of chronic degenerative diseases [ 6 ]. In addition, Se has a positive impact on the detoxification of Hg and As, as an antagonist alleviating toxicity symptoms caused by these neurotoxins [ 12 , 13 , 14 ].…”

“…The data indicate a need for the continuous monitoring of As and Se concentrations in fish from different fishing areas and in different species. This is particularly pertinent in light of the increasing global consumption of fish [ 19 ], which, despite its high nutritional value (high-quality protein, omega-3 fatty acids, vitamins, and minerals), may result in an increased intake of hazardous compounds, including trace elements such as Hg or As [ 2 , 12 ]. Monitoring the levels of As and Se in fish is also crucial due to the accumulated and prolonged intake of these elements, which can lead to adverse health effects.…”