Scientists at the KTH Royal Institute of Technology in Sweden have announced a breakthrough method to extract phosphorus from Baltic Sea sediments, offering a potential new domestic source of one of agriculture’s most essential inputs. Europe depends heavily on imported phosphate rock yet has almost no natural deposits of its own – a vulnerability exposed since geopolitical shocks in 2022 disrupted fertiliser markets.
The Baltic Sea is one of the world’s most oxygen-depleted major bodies of water. The reason is excessive concentrations of phosphorus, an important ingredient in fertiliser. The KTH team argues these deposits could be turned from an environmental liability into a strategic asset.
Microbes loosen phosphorus; chemistry lifts it out
The researchers have developed a two‑step extraction process. Microbial treatment first “loosens” phosphorus from the sediment structure. A metal‑binding compound is then added to release the phosphorus further, enabling it to be captured and converted into a fertiliser‑ready form.
Early lab tests released 80% of sediment phosphorus, with 99% of that recovered – a strikingly high recovery rate. Beneficial microbial activity also increased during the process, suggesting a favourable biological environment.
“This new method to reclaim phosphorus from sediments could reduce dependence on imported phosphate rock,” said lead researcher associate professor Zeynep Cetecioglu.
A strategic opportunity for Europe’s fertiliser independence
If scaled, the technology could help Europe tackle two major challenges at once: securing domestic fertiliser supply at a time of persistent geopolitical uncertainty, and reducing eutrophication by removing nutrient loads from one of the continent’s most environmentally stressed seas.
The EU currently relies on imports from politically volatile regions, leaving farmers exposed to price shocks and supply disruptions. A Baltic‑derived phosphorus source would not eliminate imports but could form a new pillar of regional resilience – especially valuable as fertiliser markets tighten.
Cetecioglu says the innovation could become a building block for EU circular nutrient economies, aligning with Brussels’ long‑term ambitions for nutrient recycling and sustainable fertiliser systems.
Not ready for open-water use – yet
The team stresses that the method cannot be deployed directly in the sea. It must be implemented in enclosed, land‑based facilities to prevent ecological damage. The next phase will involve replacing the metal‑binding compound with more sustainable, biologically derived alternatives such as organic acids.
While the technology is still in development, its potential impact is far‑reaching. As Cetecioglu puts it, “By offering technology for nutrient recovery and pollution control, it strengthens Europe’s ability to address eutrophication in coastal waters and move toward circular nutrient economies.”
