Mercury is a chemical element with symbol Hg and atomic number 80. It is the only metallic element that is liquid at standard conditions for temperature and pressure.
It can be present in the environment under different forms, and while none of them have a positive role in the human body, its toxicity varies with its chemical form, exposure, the amount and the vulnerability of the person exposed.
The consumption of canned tuna is important due to its health benefits but it must be balanced, as all the other food we include in our diet. According to Raloff (2010) tuna is considered healthy food as it “boosts neural development in babies and protects the hearts and minds of adults”.
“Although fish may contain harmful compounds, it is also a very important source of nutrients, especially of long-chain n-3 fatty acids, high quality protein, selenium and vitamin D, and is relatively low in cholesterol.” (González-Estecha et al., 2013, p.48)
Raloff (2010) suggests that people “with enough information about the fish they are buying might be able to negotiate the mercury minefield and tap tuna’s dietary benefits.” The author also found that “mercury content can vary dramatically between tuna species, depending on size. Bigger fish tend to accumulate more of the toxic metal.”
According to some authors, the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA), yellowfin tuna has medium to high contaminant levels and bigeye has the highest contaminant levels, while skipjack tuna and atlantic mackerel have the lowest contaminant levels.
In the EPA and FDA “What you Need to Know about Mercury in Fish and Shellfish” for the most vulnerable populations, they advise to eat around 350g per week of a variety of fish and seashell that are low in mercury. These include skipjack tuna (light tuna), the only specie we use in our products.