In recent years, the presence of per- and polyfluoroalkyl substances (PFAS) in agricultural environments has emerged as a critical environmental and public health concern. PFAS, often termed “forever chemicals” due to their extraordinary persistence, are now increasingly detected in farmland soils globally, raising alarms regarding their potential to threaten food safety and human well-being. A comprehensive new literature review, published in the journal New Contaminants, synthesizes the current understanding of PFAS sources and their transport mechanisms within soil–plant systems, unveiling complex interactions that influence how these synthetic compounds accumulate in crops and, ultimately, enter the human food chain.
PFAS comprise a vast family of synthetic fluorinated compounds characterized by strong carbon–fluorine bonds, some of the strongest in organic chemistry, which confer remarkable chemical stability. Since their inception in the 1940s, PFAS have been widely incorporated into various consumer and industrial products, including non-stick cookware, stain-resistant textiles, food packaging, firefighting foams, and cosmetics. This long history of extensive use, coupled with their resistance to environmental degradation, has resulted in pervasive environmental contamination. PFAS compounds can persist unabated in soil, water, and living organisms, leading to their designation as “forever chemicals.”
Central to the recent review was an exhaustive analysis of global waste and wastewater data, alongside a meticulous evaluation of 115 peer-reviewed studies published between 2005 and 2025. The findings underscore the pivotal role of biosolids—nutrient-enriched byproducts generated by sewage treatment processes—in introducing PFAS into agricultural soils. Biosolids frequently contain elevated levels of these substances as a consequence of urban and industrial waste inputs. Their widespread application as soil amendments, intended to recycle nutrients and organic matter, paradoxically propagates PFAS contamination within farming systems, with hotspots of concern identified predominantly in Western Europe, Australia, and East Asia.
Delving deeper into the behavior of PFAS species in soil–plant milieus, the research reveals a distinct dichotomy based on molecular chain length. Long-chain PFAS compounds demonstrate a high affinity for soil particles, particularly organic matter and clay minerals, leading to their strong adsorption and accumulation predominantly in plant root tissues. This behavior significantly limits their upward mobility in the plant, yet facilitates prolonged retention within the rhizosphere and surrounding soil matrix. Conversely, short-chain PFAS exhibit increased water solubility and mobility, facilitating their translocation through the soil profile and into the aerial parts of plants including leaves and grains. This dynamic poses particular challenges for crops that are consumed whole, as it raises the potential for greater human exposure.
Among staple crops assessed in the review, soybeans stood out for exhibiting unusually high burdens of PFAS accumulation. The authors suggest this phenomenon is linked to the crop’s high protein content, which may influence PFAS binding and retention mechanisms within plant tissues. This discovery is especially significant because soybeans constitute a major protein source globally, often consumed directly or processed into myriad food products. The propensity for PFAS bioaccumulation in high-protein crops signals a potential dietary exposure pathway that has been largely underestimated until now, necessitating urgent regulatory attention.
The biological and toxicological implications of PFAS uptake by crops possess far-reaching consequences. Scientific research increasingly documents that PFAS exposure can disrupt endocrine systems, impair developmental processes, contribute to reproductive toxicity, and elevate risks for chronic diseases such as cancer and immune dysfunction. The persistent and bioaccumulative nature of these chemicals amplifies these concerns, considering that dietary intake remains a major route of human exposure. Hence, understanding and mitigating PFAS transfer from soil into the food supply is critical for safeguarding public health on a planetary scale.
Despite these emerging risks, policy responses remain fragmented and insufficient globally. The review highlights that only a limited number of countries—including the United States, Germany, and Australia—have established enforceable PFAS concentration thresholds for biosolid applications on farmland. Most agricultural regions lack comprehensive regulatory frameworks to govern the use of PFAS-contaminated waste products. The authors emphasize that immediate restrictions on biosolid reuse, which is both economically viable and enforceable, represent the most effective intervention to curtail the influx of PFAS into agricultural soils, outpacing technological remediation methods that are often cost-prohibitive and technologically incomplete.
A further innovation proposed by the study is the development of regional predictive models that integrate detailed soil physicochemical properties with PFAS migration behaviors. These models would enhance risk assessment precision by accounting for diverse soil textures, organic content, hydrology, and crop types, thereby offering bespoke strategies for contamination management. Such tools are paramount for informing targeted interventions, guiding agricultural practices, and shaping regulatory policies that reflect local geographic and agronomic realities rather than generic one-size-fits-all approaches.
This growing body of evidence concerning PFAS contamination intricately ties into the global transition toward circular economy principles and the expanding reuse of wastewater and biosolids. While such sustainability-driven strategies hold substantial promise for reducing resource waste and enhancing soil fertility, they inadvertently risk propagating persistent toxicants across food production systems if chemical pollutants like PFAS are not rigorously controlled. The review collectively warns that without heightened scientific vigilance and policy action, the environmental benefits of these practices may be undermined by unintended health hazards.
The future trajectory of PFAS research must therefore prioritize multidisciplinary investigations that interlink environmental chemistry, plant physiology, toxicology, and agricultural sciences. Longitudinal field studies combined with laboratory experiments should elucidate PFAS partitioning, bioavailability, and transformation within complex soil–plant interfaces. Moreover, advancing analytical detection techniques is critical for accurately quantifying trace-level PFAS compounds in diverse matrices, thereby supporting surveillance and compliance monitoring.
In conclusion, the pervasive contamination of agricultural soils by PFAS represents a formidable challenge at the intersection of environmental sustainability, food safety, and public health. As these enduring chemicals infiltrate our crops and diets, decisive and coordinated global actions are imperative to mitigate their spread, protect ecosystems, and ensure the safety of future food supplies. Only through integrated science-based policies, innovative modeling approaches, and responsible waste management can the silent invasion of PFAS in our agricultural landscapes be effectively countered.
Subject of Research: Not applicable
Article Title: Sources and transport of per- and polyfluoroalkyl substance (PFAS) in agricultural soil–plant systems
News Publication Date: 4-Sep-2025
Web References:
References:
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. DOI: 10.48130/newcontam-0025-0007
Image Credits: Miao Han, Chao Qin & Yanzheng Gao
Keywords: Adsorption, Soils, Plants
