Benefits and risks associated with consumption of raw, cooked, and canned tuna (Thunnus spp.) based on the bioaccessibility of selenium and methylmercury

Influence of bioaccessibility of total mercury, methyl-mercury and selenium on the risk/benefit associated to the consumption of raw and cooked blue shark (Prionace glauca)

“…This was also observed in another study on blue shark, where the ratio was 5 (Escobar-Sánchez et al, 2011). The opposite was found in raw samples by Afonso et al (2008Afonso et al ( , 2013Afonso et al ( , 2015b in other predatory species (e.g. tuna, black scabbard-fish, silver scabbard-fish, ray, hake, angler and blackbelly rosefish).…”

Bioaccessibility and bioavailability of methylmercury from seafood commonly consumed in North America: In vitro and epidemiological studies

“…Bioaccessible concentrations of MeHg measured in the present study generally fall into the reported range for a given type of seafood for two of three species. For instance, the bioaccessible concentration of MeHg from fresh tuna measured in our work, 493 ng/g ww, fell within the reported range of 106 ng/g ww to 680 ng/g ww seen in the literature (Cabanero et al, 2007; Ouedrago et Amyot, 2011; Afonso et al, 2015). The bioaccessible concentration of MeHg from tilapia measured in our work, 11 ng/g ww, was similar to the 13 ng/g ww seen in the literature (Wang et al, 2013).…”

“…The bioaccessible concentration of MeHg from tilapia measured in our work, 11 ng/g ww, was similar to the 13 ng/g ww seen in the literature (Wang et al, 2013). However, the bioaccessible concentration of MeHg from canned white tuna measured in our work, 255 ng/g ww, was much higher than what has been previously reported (60 or 40 ng/g ww for THg; 40 ng/g ww for MeHg) (Afonso et al, 2015). The differences between our results and the work by Afonso et al (2015) may be due, in part, to the use of alternate in vitro gastrointestinal digestion protocols as this has been shown to affect the bioaccessibility of MeHg.…”

“…However, the bioaccessible concentration of MeHg from canned white tuna measured in our work, 255 ng/g ww, was much higher than what has been previously reported (60 or 40 ng/g ww for THg; 40 ng/g ww for MeHg) (Afonso et al, 2015). The differences between our results and the work by Afonso et al (2015) may be due, in part, to the use of alternate in vitro gastrointestinal digestion protocols as this has been shown to affect the bioaccessibility of MeHg. In addition, the source and processing of canned tuna may have some influence on the initial MeHg concentration and bioaccessibility.…”

“…This variation within types of seafood was also seen in the literature. For instance, for canned white tuna, the SD calculated in our work was 80.6 ng/g ww, and the SD calculated in the literature was 50 ng/g ww (Afonso et al, 2015). High variability may be due to differences in protein, peptide, and amino acid profiles of the individual pieces of seafood muscle tissue, that were each purchased on separate days from a variety of Montreal markets.…”