Just 22% of fish, seafood species in western Mediterranean have safe mercury levels

By Alyssa McMurtry

OVIEDO, Spain (AA) - Spanish scientists found that of 58 fish and seafood species sold in local markets in Spain, Italy and France, just 13 presented mercury concentrations that the European Union considers safe.

“According to these results, public health authorities should pay special attention to the fish and seafood with the highest levels of mercury and make appropriate preventive health recommendations, especially for pregnant women and children,” said lead scientist Joan Grimalt in a statement on Monday.

The study, conducted by scientists from Spain’s Institute of Environmental Assessment and Water Research (IDAEA-CSIC), analyzed 1,345 fish samples that were caught in the western Mediterranean.

The species with the lowest levels of mercury were sardines, anchovies and salema. However, the consumption of salema, or dreamfish, is not always risk-free. On rare occasions, the species of seabream has caused psychedelic trips that last for days.

Since mercury levels are biomagnified on each level of the marine food chain, only one large predatory fish had acceptable levels of the heavy metal — the common dolphin fish, also known as mahi-mahi.

Other fish and sea creatures that made the cut in terms of mercury were the common squid, painted comber, striped red mullet, picarel, two types of seabream, the pearly razorfish and the brown meagre.

Not a single shellfish species met the EU’s threshold for safe mercury levels.

Mercury is a widespread toxic element that can damage kidneys, lungs, cardiovascular and nervous systems. Children younger than five and embryos of pregnant women are particularly vulnerable to its effects.

The Mediterranean Sea feeds more than 480 million people with fish each year, but many studies have found it is a hot spot for the metal compared to other bodies of water.

The study’s authors recommend eating low-mercury species to benefit from the healthy fats contained in fish while avoiding toxicity.

The study was published in the December 2022 issue of the peer-reviewed journal Environmental Pollution.