H2020 LEX4BIO Project: Optimizing Bio-Based Fertilizers in Agriculture: A Knowledge Base for New Policies

A Comprehensive Analysis of the Potential of Bio-Based Fertilizers. Extensive research and testing of around 80 bio-based fertilizers has demonstrated their agronomic efficiency, health and environmental safety, and optimal fertilization strategies. The world's population is growing, and at the same time, its food crops are facing more severe and frequent weather events, as well as other threats stemming from climate change. The production of conventional fertilizers that improve crop productivity generates greenhouse gas emissions and is harmful to the environment.

Large quantities of raw materials are available for the production of alternative fertilizers. Nitrogen and phosphorus, essential for agricultural production, are found in manure, sewage sludge, bio-waste, and animal by-products. Their reuse in bio-based fertilizers (BBFs) improves the circularity of European food production. BBFs can also improve soil health, reduce environmental impact, and decrease Europe's dependence on imported apatite-based phosphorus fertilizers and fossil-intensive mineral nitrogen fertilizers. The EU-funded LEX4BIO project aimed to demonstrate the potential of BBFs to replace mineral fertilizers, while minimizing environmental impact and ensuring food safety and human health.

Developing a BBF Knowledge Base LEX4BIO evaluated around 80 BBFs, far exceeding the grant agreement targets. “Extensive field trials of their agronomic efficiency at different European locations showed that most of the tested BBFs can supply phosphorus and nitrogen to arable crops as well as mineral fertilizers, while others offer long-term benefits such as maintaining soil quality,” explains project coordinator Kari Ylivainio of the Natural Resources Institute of Finland. The high water solubility of phosphorus is commonly considered a prerequisite for high-quality fertilizers. “We show that this is not the case for BBFs, and that low solubility can even be beneficial in reducing phosphorus leaching losses,” notes Ylivainio. Customized fertilization strategies (application rate, duration, and method) based on soil, crop, and BBF type will ensure that site-specific nutrient requirements are met and environmental emissions are minimized.

Addressing Environment, Safety, and Health Published research has drawn attention to the potential challenges of biocompatible fertilizers (BBFs), such as the introduction of contaminants and pathogens into the soil. However, the implementation of extensive ecotoxicological testing developed within the project demonstrated that “contaminant levels in the investigated BBFs remained below EU reference values, with no significant risk of accumulation of hazardous substances in the soil or increased antibiotic resistance,” says Ylivainio. LEX4BIO developed a protocol for conducting life-cycle analyses of fertilizer products. This will enable harmonized assessments, supporting policymakers and stakeholders in assessing the ecological and environmental impacts of BBF implementation. “Most importantly, the analyzed BBFs proved to be safe from the perspective of food and feed safety, as well as human health,” emphasizes Ylivainio.

Holistic Consideration of Social and Political Factors LEX4BIO also examined the drivers and barriers to replacing conventional fertilizers with BBFs along the value chain. The project identified variations, including in farmer and consumer attitudes toward waste recycling. The identification of obstacles to social acceptance highlights the need for a holistic effort that includes awareness campaigns and legislative changes to facilitate the widespread use of BBFs. LEX4BIO's extensive testing and analysis have already led to 17 publications, and many more are in preparation to add to the knowledge base.

Although organic fertilizers have been added to the European Fertilizer Products Regulation (EU) 2019/1009, "the transition from synthetic to organic fertilizers will be a complex process dependent on economic, technological, and social factors. More research is needed to optimize the safe and sustainable use of BBFs under various growing conditions, bringing Europe closer to a circular economy and self-sufficiency in food production," Ylivainio concludes.