According to official data, the average person in Spain consumes 10.5kg of fish a year, putting Spain up there with Japan and Norway as top fish consumers.

Without doubt, fish is good for you – it’s not so hot for fish life, mind – but it’s good for us. However, there is the question of mercury contamination in the fish that we eat, especially the bigger kinds like tuna and swordfish etc.

Mercury (Hg) is present naturally, as well as what we humans dump in rivers and the sea. In fish, it’s a neurotoxin that can cause disorders in the nervous system.

We know this, of course, unlike the Victorians who had lead plumbing and let boys play with lead soldiers, for instance. Which is why we are pretty keen on keeping it well away from pregnant mothers and babies.

Anyway, a study carried out by researchers from Valencia published a report in the Spanish Journal for Public Health showing which fish are the biggest culprits when it comes to mercury contamination. Their research results actually show that the concentration of this toxic metal is going down, but even so, there are three groups of fish that pose a greater risk

The swordfish and louvar (known in Spain as emperador) are the biggest culprit, according to the study, reaching 0.80 mg/kg. While the fresh tuna and bonito group was the second with the highest concentration, reaching 0.48 mg/kg. It is closely followed by canned tuna, which is third on this list with 0.28 mg/kg.

To avoid health problems caused by consuming mercury, the Spanish Agency for Food Safety and Nutrition (Agencia Española de Seguridad Alimentaria y Nutrición or Aesan for short) has recommendations for consuming this kind of fish: children up to ten also should avoid eating them, together with children from three and under, pregnant women and breastfeeding mothers.

As for kids of ten and upwards to 14 the criterion is a maximum of one serving of these fish once a week. Kids over 14 will be gorging themselves on trash food anyway, so what the hell.

Aesan goes further than the Valencian researchers and also includes shark and pike besides swordfish, emperor and bluefin tuna.

(News/Noticias: Spain)