A new review study has revealed that per- and polyfluoroalkyl substances (PFAS), widely known as "forever chemicals," are increasingly entering farmland soils through waste recycling and wastewater reuse. Once in the soil, PFAS can migrate into crops, raising urgent concerns for food safety and human health.
PFAS are a group of synthetic chemicals first developed in the 1940s. They have been extensively used in non-stick cookware, food packaging, textiles, firefighting foams, and cosmetics. Thanks to their strong carbon–fluorine bonds, PFAS are extremely resistant to degradation, persisting in the environment and in living organisms for decades. Mounting evidence has linked PFAS exposure to endocrine disruption, developmental and reproductive toxicity, and long-term health risks.
The study, published in New Contaminants, compiled global waste and wastewater data from the United Nations and analyzed 115 research papers published between 2005 and 2025. The findings show that biosolids—nutrient-rich byproducts from sewage treatment—are the primary source of PFAS in agricultural soils, with the highest risks identified in Western Europe, Australia, and East Asia.
Importantly, the research highlights distinct behaviors of PFAS in soil–plant systems: long-chain PFAS tend to bind strongly to soils and accumulate in plant roots, while short-chain PFAS are more mobile, moving upward with water and concentrating in leaves and grains. Among major crops, soybeans showed particularly high PFAS burdens due to their high protein content, compared to rice, wheat, and maize.
"This means that everyday foods—especially high-protein crops like soybeans—could become important pathways for PFAS to enter the human diet," the authors warn.
Despite the risks, regulatory frameworks remain limited. Only a handful of countries, including the United States, Germany, and Australia, have imposed PFAS limits on biosolids used in agriculture. Most regions worldwide still lack enforceable standards. The authors stress that restricting the reuse of PFAS-laden waste products is the most cost-effective and rapid strategy to reduce PFAS entry into farmland soils, compared to relying solely on expensive and incomplete cleanup technologies.
The study also recommends developing regional predictive models that integrate soil properties with PFAS migration patterns, providing more accurate tools to assess contamination risks across diverse agricultural landscapes.
"As the world embraces circular economy practices and wastewater reuse, we must remain vigilant about the unintended consequence of spreading persistent pollutants into our food systems," the researchers conclude.
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Journal reference: Han M, Qin C, Gao Y. 2025. Sources and transport of per- and polyfluoroalkyl substance (PFAS) in agricultural soil–plant systems. New Contaminants 1: e005 https://www.maxapress.com/article/doi/10.48130/newcontam-0025-0007
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About the Journal:
New Contaminants is an open-access journal focusing on research related to emerging pollutants and their remediation.
