Scientists Slash Mercury in Canned Tuna by 35% Using Simple Amino Acid
Scientists at Chalmers University of Technology have found a way to cut mercury levels in canned tuna by up to 35%. Their method involves soaking the fish in a cysteine solution, a simple amino acid. The breakthrough could help reduce exposure to a chemical the World Health Organisation ranks among the most dangerous for human health.
Separately, new packaging and transport innovations are also improving seafood safety and sustainability. Companies like DS Smith and Aptar Food Protection have introduced eco-friendly pallets and active packaging to extend freshness and reduce waste.
The research team tested the cysteine treatment on minced tuna bought from ordinary supermarkets. When immersed in the solution, the mercury content dropped by as much as 35%. The key factor was surface area—the more fish flesh exposed to the liquid, the more mercury was removed.
After two weeks, the process reached its limit, with no further reduction in mercury levels. Cell-based tests confirmed that the treated tuna remained safe to eat, with no harmful side effects from the treatment. Mercury poses serious risks, particularly to foetuses and young children, by damaging the central nervous system. The WHO lists it among the top ten most hazardous chemicals for humans. While the study did not reference specific WHO guidelines on tuna consumption, the findings offer a practical way to lower exposure. Beyond mercury reduction, the seafood industry is adopting other safety measures. Danish producer Vilsund Blue A/S switched to fibre-based pallets from DS Smith, replacing plastic for transporting canned products. Meanwhile, Aptar Food Protection's SeaWell packaging slows microbial growth, prevents chemical breakdown, and keeps seafood looking and smelling fresh for longer.
The new cysteine treatment provides a straightforward way to reduce mercury in tuna without compromising safety. If scaled up, it could lower health risks linked to seafood consumption. Alongside advances in packaging and logistics, these innovations aim to make seafood both safer and more sustainable for consumers.
