Phosphorus sustains global food production and is, therefore, of crucial importance to human nutrition and health. However, its mismanagement can lead to water pollution and environmental degradation in addition to low crop yields. In many parts of sub-saharan Africa, phosphorus deficiency constrains agricultural productivity and exacerbates food insecurity. Despite these challenges, phosphorus remains a fragmented topic in global and African policy. To address these issues, the 8th Sustainable Phosphorus Summit (SPS8) was convened in Africa for the first time. SPS8 took place in Accra, Ghana, between 30th September and 3rd October 2025. The Summit was an international collaboration, with co-conveners from the Council for Scientific and Industrial Research (CSIR) – Ghana, the Forum for Agricultural Research in Africa (FARA), The UK Centre for Ecology & Hydrology West Africa Office, Lancaster University and Rothamsted Research. In this paper, we give a detailed overview of the key messages and insights that emerged from highlight talks, lectures, working groups and field trips. We also discuss and reflect on the challenges of delivering an inclusive summit, from designing solutions to benefit-sharing. SPS8 demonstrates that inclusive, cross-sector knowledge-exchange events are crucial to support and enable phosphorus sustainability on the continent of Africa and globally and to enable the next generation of interdisciplinary phosphorus researchers.

BackgroundThe circular phosphorus (P) economy addresses economic and environmental penalties inherent to the current linear P economy. Phosphorus sources recovered from waste steams (recyclates) offer an alternative to conventional fertilizers.AimThis research aimed to assess the agronomic performance of P recyclates derived from wastewater (hazenite, struvite), treated sewage sludge ash (SSA) and compost (FOGO food organics/garden organics) with crops previously characterized for P use efficiency (PUE).MethodsPhosphorus was supplied as granules and benchmarked against conventional fertilizers or mineral solution. Grown in controlled conditions, crops received recyclates individually or as amalgamates, with or without additional water-soluble P. We quantified P uptake, yield and phytate content, and calculated agronomic performance indicators.ResultsResults revealed that (1) crop genotypes with purportedly lower or higher PUE showed similar performance when grown with limiting P supply and/or less soluble P recyclates, (2) crop performance improved when less soluble P recyclates were combined with water-soluble P, (3) crops produced similar yield and biomass when supplied with an organo-mineral formulation, hazenite, or conventional fertilizer, (4) grain accumulated higher levels of the antinutrient phytate with excess soluble P.ConclusionWe conclude that suitably formulated P recyclates can supplement or replace conventional fertilizers, and that fertilizer design should consider the solubility of recyclates and a crop's ability to access less soluble P. This adds to the growing body of evidence that well-formulated next-generation fertilizers can efficiently nourish crops. Integrating insights from controlled experiments and field trials is a cost-effective strategy to actualize the circular P economy.

Advanced phosphorus (P) recycling from wastewater is critical for improving nutrient circularity and reducing soil pollution associated with the direct application of sewage sludge in agriculture. However, few studies evaluate the long-term environmental and economic trade-offs between recycled P products and raw sewage sludge application. This study compares struvite, vivianite, and dicalcium phosphate (CaP) as P alternatives to sludge to mitigate heavy metal accumulation in Spanish agricultural soils. Using data from 27,835 plots, heavy metal accumulation was simulated over 50- and 100-year fertilisation scenarios. The results indicate that continuous sludge application leads to widespread exceedances of zinc, copper, and cadmium, especially in alkaline soils, whereas substitution with recycled products can substantially reduce these risks. Vivianite balances P recycling and costs, CaP offers the best environmental performance but with higher investment, and struvite suits smaller regions prioritising environmental safety. Economic analysis favours advanced recycling over sludge, especially considering externalities such as soil remediation costs. Despite limitations, our findings emphasise the importance of integrating environmental externalities into economic assessments and the value of advanced P recycling for sustainable soil management.

The global phosphorus challenge arises from the uneven distribution of phosphorus resources, environmental effects from phosphorus losses and unsustainable linear management. Despite progress in advanced phosphorus recycling, less than 1% of secondary phosphorus resources produced globally are recycled. In this Review, we comprehensively explore global barriers to phosphorus recycling. Manure (15–20 million tons P (MtP) yr−1), mining and fertilizer industry waste (6–12 MtP yr−1), wastewater (~3.7 MtP yr−1) and food waste (~1.2 MtP yr−1) are the major secondary phosphorus resources worldwide. In addition, accumulated legacy phosphorus in soil and sediment comprises a combined stock of more than 3,200 MtP. Phosphorus mismanagement and losses cost stakeholders US$265 billion annually, yet substantial barriers to phosphorus recycling remain. Key challenges to be overcome include low competitiveness of recycled phosphorus products, complex waste handling, limited legacy phosphorus recovery and fragmented collaboration among stakeholders. A shift is needed towards an integrated, systems-based approach that simultaneously addresses technical, economic and societal challenges. Transdisciplinary strategies and research will advance phosphorus recycling and the development of a sustainable, circular phosphorus economy. Incorporating the perspectives of diverse stakeholders will help drive increasingly sustainable phosphorus management. Achieving phosphorus circularity is a key challenge to realizing sustainable phosphorus use, and recycling is a major route to accomplish this goal. This Review explores global barriers to phosphorus recycling and discusses approaches to overcome the technical, economic and societal challenges in attaining sustainable phosphorus management.

Brazil is an agricultural giant that plays a crucial role in the Global Phosphorus Challenge (GPC), and whose highly weathered soils are currently dependent on phosphorus (P) fertilizers derived from phosphate rock, a dwindling and critical resource. Brazil imports > 50% of its P fertilizers and P recovery from waste is not yet explored in the country, making it vulnerable to market instabilities, phosphate rock availability, and geopolitical conflicts. To make matters worse, Brazilian research budget has been shrinking for 7 years straight, hindering scientific efforts and causing significant ‘brain drain’, further undermining the country’s capacity to tackle this critical problem. However, an opportunity comes with the new Brazilian Federal government (starting January 2023), which promises to make significant investments in science and higher education. We call for all stakeholders to seize this important moment and timely collaborate in creating multidisciplinary P-related projects, taking advantage of the soon-to-be available resources to develop knowledge, technologies, and training networks to shape a new generation of experts in P management in the tropics. We are confident that through agriculture intensification, intelligent use of resources, new legislation and governance, Brazil will stride towards sustainable food production, bringing immediate value to Brazil and the world by protecting the Amazon forest and advancing to overcome the GPC.

Finding alternative phosphorus sources is imperative to address negative environmental and societal impacts caused by its current inefficient use. However, the direct use of phosphorus in sewage sludge in agriculture is controversial. This paper uses Denmark, Germany, and Spain as case examples to assess relevant legislation and boundary conditions in agricultural production to identify opportunities and barriers for the utilisation of recycled phosphorus from wastewater in agriculture on a regional level. Only five out of 22 phosphorus recycling technologies considered were in full compliance with legislation across all three countries, and these five were then assessed for their potential to supply phosphorus to major crops within countries. We considered the application of technologies across four scenarios: 1) struvite; 2) vivianite as iron supply; 3) vivianite for calcium phosphate precipitation; and 4) ashes for calcium phosphate precipitation. The most suitable scenario identified for Denmark was vivianite for calcium phosphate precipitation, whereas in Spain vivianite as iron supply was identified as most suitable, and ashes for calcium phosphate in Germany. We found that in 2018, the potential phosphorus supply from recycling technologies was on average 0.38, 0.29 and 0.05 kg of phosphorus per capita for Danish, German, and Spanish regions. These quantities could meet 9.1, 21.7, and 10.0 percent of the phosphorus required to produce major cereals in each country (specifically wheat, barley, and rye). Given current legal constraints, wastewater treatment plant connections and agronomic context, the potential contribution of recycled phosphorus is non-negligible in many sub-national regions. Still, to access the full potential of phosphorus circularity clear product specifications and transport and logistics among regions will be necessary.

Throughout history, the first and foremost role of urban water management has been the protection of human health and the local aquatic environment. To this end, the practice of (waste-)water treatment has maintained a central focus on the removal of pollutants through dissipative pathways. Approaches like – in the case of wastewater treatment – the activated sludge process, which makes 'hazardous things' disappear, have benefitted our society tremendously by safeguarding human and environmental health. While conventional (waste-)water treatment is regarded as one of the greatest engineering achievements of the 20th century, these dissipative approaches will not suffice in the 21st century as we enter the era of the circular economy. A key challenge for the future of urban water management is the need to re-envision the role of water infrastructure, still holding paramount the safeguard of human and environmental health while also becoming a more proactive force for sustainable development through the recovery of resources embedded in urban water.This book aims (i) to explain the basic principles governing resource recovery from water (how much is there, really); (ii) to provide a comprehensive overview and critical assessment of the established and emerging technologies for resource recovery from water; and (iii) to put resource recovery from water in a legal, economic (including the economy of scale of recovered products), social (consumer's point of view), and environmental sustainability framework.This book serves as a powerful teaching tool at the graduate entry master level with an aim to help develop the next generation of engineers and experts and is also highly relevant for seasoned water professionals and practicing engineers.ISBN: 9781789060317 (Paperback)ISBN: 9781780409566 (eBook)

The research was undertaken as part of

Food security and healthy freshwater ecosystems are placed at jeopardy by poor phosphorus management. Scientists are calling for transformation across food, agriculture, waste and other sectors — mobilized through intergovernmental action, which has been missing thus far.

Business case evaluation of five centralised anaerobic digesters applying nutrient recovery and reuseA product from the H2020 project SYSTEMIC Hermann, L.

The Baltic Sea is considered the marine water body most severely affected by eutrophication within Europe. Due to its limited water exchange nutrients have a particularly long residence time in the sea. While several studies have analysed the costs of reducing current nutrient emissions, the costs for remediating legacy nutrient loads of past emissions remain unknown. Although the Baltic Sea is a comparatively well-monitored region, current data and knowledge is insufficient to provide a sound quantification of legacy nutrient loads and much less their abatement costs. A first rough estimation of agricultural legacy nutrient loads yields an accumulation of 0.5–4.0 Mt N and 0.3–1.2 Mt P in the Baltic Sea and 0.4–0.5 Mt P in agricultural soils within the catchment. The costs for removing or immobilising this amount of nutrients via deep water oxygenation, mussel farming and soil gypsum amendment are in the range of few tens to over 100 billion €. These preliminary results are meant as a basis for future studies and show that while requiring serious commitment to funding and implementation, remediating agricultural legacy loads is not infeasible and may even provide economic benefits to local communities in the long run.

Low-grade phosphate rock from Sra Ouertane (Tunisia) was beneficiated using a thermal treatment consisting of calcination, quenching, and disliming. Untreated phosphate rock samples (group 1), calcined phosphate rock samples (group 2), as well as calcined, quenched, and dislimed (group 3) phosphate rock samples, were investigated using inductively-coupled plasma atomic emission spectroscopy (ICP-AES), inductively-coupled plasma mass spectrometry (ICP-MS), thermogravimetric analysis (TGA), and X-ray powder diffraction (XRD). Besides, the particle size distribution of the aforementioned three groups was determined. The proposed thermal treatment successfully increased the P2O5 content of the untreated phosphate rock from 20.01 wt% (group 1) to 24.24 wt% (group 2) after calcination and, finally, 27.24 wt% (group 3) after calcination, quenching, and disliming. It was further found that the concentration of relevant accompanying rare earth elements (Ce, La, Nd, Pr, Sm, and Y) was increased and that the concentration of Cd could be significantly reduced from 30 mg/kg to 14 mg/kg with the proposed treatment. The resulting phosphate concentrate showed relatively high concentrations in metal oxides: Ʃ MgO, Fe2O3, Al2O3 = 3.63 wt% and silica (9.81 wt%) so that it did not meet the merchant grade specifications of a minimum P2O5 content of 30 wt% yet. Removal of these elements could be achieved using additional appropriate separation techniques.

Despite the significant reduction of phosphorus (P) discharge in the Baltic Sea in the last decades, obtained through the implementation of some approaches within the Helsinki Convention, eutrophication is still considered the biggest problem for the Baltic Sea environment. Consequently, the reduction of P load is an urgent need to solve, but the complexity of both the environmental and legislative context of the area makes this process difficult (more than in the past). Eutrophication is an intricate issue requiring a proper framework of governance that is not easy to determine in the Baltic Sea Region where the needs of several different countries converge. To identify the most suitable strategy to reduce the eutrophication in the Baltic Sea, the InPhos project (no. 17022, 2018–2019, funded by the European Institute of Innovation & Technology (EIT) Raw Materials) adopted a holistic approach considering technical, political, economic, environmental and social aspects of P management. With the aims to raise awareness about the P challenge, foster the dialogue among all the stakeholders, and find solutions already developed in other countries (such as Germany and Switzerland) to be transferred in the Baltic Sea Region, the InPhos project consortium applied the methodology proposed in this paper, consisting of three main phases: (i) analysis of the available technologies to remove P from waste streams that contribute to eutrophication; (ii) analysis of the main streams involving P in Baltic Sea countries to highlight the potential of more sustainable and circular P management; (iii) study of the current context (e.g., already-existing initiatives and issues). This approach allowed us to identify four categories of recommendations and practical actions proposed to improve P management in the Baltic Sea region. During the project, the consortium mainly addressed social aspects. Following steps beyond the project will be more quantitative to determine the techno-economic feasibility of circular P management in selected demo cases in the region.

ADVERTISEMENT RETURN TO ISSUEPREVViewpointNEXTNew Training to Meet the Global Phosphorus ChallengeKasper Reitzel*Kasper ReitzelUniversity of Southern Denmark, Department of Biology, Campusvej 55, 5230 Odense M, Denmark*E-mail: [email protected]More by Kasper Reitzel, William W. BennettWilliam W. BennettUniversity of Southern Denmark, Department of Biology, Campusvej 55, 5230 Odense M, DenmarkMore by William W. Bennett, Nils BergerNils BergerEuroChem Agro GmbH, Reichskanzler-Müller-Str. 23, 68165 Mannheim, GermanyMore by Nils Berger, Will J. BrownlieWill J. BrownlieCentre for Ecology & Hydrology in Edinburgh, Penicuik, Midlothian, Scotland, U.K. EH26 0QBMore by Will J. Brownlie, Sander BruunSander BruunUniversity of Copenhagen, Department of Plant and Environmental Sciences, Thorvaldsensvej 40, 1871 Frederiksberg C, DenmarkMore by Sander Bruun, Morten L. ChristensenMorten L. 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MetsonLinköping University, Department of Physics, Chemistry and Biology, Fysikhuset, Rum 3D.306 SE-58183 Linköping, SwedenMore by Geneviève S. MetsonCite this: Environ. Sci. Technol. 2019, 53, 15, 8479–8481Publication Date (Web):July 8, 2019Publication History Received12 June 2019Published online8 July 2019Published inissue 6 August 2019https://doi.org/10.1021/acs.est.9b03519Copyright © 2019 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views6747Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (3 MB) Get e-AlertsSUBJECTS:Gel permeation chromatography,Sustainability,Water pollution,Phosphorus,Food Get e-Alerts

The regulatory framework governing anaerobic digestion and biogas production in EU Member States is arranged in European Policies, Regulations and Directives and by national legislation, which is based on European Policies and Directives. Consequently, we have organised the Regulatory Framework Report following the same structure. Chapter 1 deals with European Policies which are followed by European Regulations that must be enforced by all Member States as they are in chapter 2. Chapter 3 refers to European Directives which must be adopted by Member States but not literally. Directives typically stipulate a target but leave room for selecting the strategy and pathway by the Member State. Chapter 4 briefly deviates from legislation and provides - extracted from the EBA Annual Reports - statistical information on the regional development of electricity from biogas and biomethane production in Europe clearly showing Germany in the lead but higher recent dynamics regarding biomethane in France and Nordic countries. In chapter 5 the report returns to legislation in Member States, starting with comprehensive information on the countries with demonstration plants. Chapter 6 deals with legislation in countries with outreach plants and chapter 7, finally, gives an overview of all Member States.