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

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 mu g g(-1) w.w. and from 0.57 to 0.97 mu g g(-1) w.w., respectively, whereas Se levels were 0.49-0.65 mu g 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.

Automated summary

This study measures the concentrations of total mercury (THg), methylmercury (MeHg), and selenium (Se) in elasmobranch fish from an Italian market. It evaluates 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. The results show that European Community limits for THg were surpassed in most samples, but none of the fish exceeded the limit for MeHg set by FAO/WHO. The study emphasizes the importance of monitoring THg and MeHg levels in fish, especially apex predators, to avoid overexposure for consumers.