Short-chain perfluoroalkyl substances (PFAS) are generally considered to be of less environmental concern than long-chain analogues due to their comparatively shorter half-lives in biological systems. Perfluorobutanoic acid (PFBA) is a short-chain PFAS with the most root–shoot transfer factor of all PFAS. We investigated the impact of extended exposure of soybean plants to irrigation water containing environmentally relevant (100 pg–100 ng/L) to high (100 µg–1 mg/L) concentrations of PFBA using phenotypical observation, biochemical characterization, and transcriptomic analysis. The results showed a non-monotonous developmental response from the plants, with maximum stimulation and inhibition at 100 ng/L and 1 mg/L, respectively. Higher reactive oxygen species and low levels of superoxide dismutase (SOD) and catalase (CAT) activity were observed in all treatment groups. However transcriptomic analysis did not demonstrate differential expression of SOD and CAT coding genes, whereas non-enzymatic response genes and pathways were enriched in both groups (100 ng/L and 1 mg/L) with glycine betaine dehydrogenase showing the highest expression. About 18% of similarly downregulated genes in both groups are involved in the ethylene signaling pathway. The circadian rhythm pathway was the only differentially regulated pathway between both groups. We conclude that, similar to long chain PFAS, PFBA induced stress in soybean plants and that the observed hormetic stimulation at 100 ng/L represents an overcompensation response, via the circadian rhythm pathway, to the induced stress.

Surface water bodies such as irrigation ponds and ditches are vital irrigation sources but can carry per- and polyfluoroalkyl substances (PFAS) from biosolid-amended fields. Field sampling showed decreasing PFAS levels from soils to ponds, with ditches serving as transport pathways; long-chain PFAS were retained in soils, while short-chain PFAS were more mobile. To test crop responses under realistic conditions, soybean plants were irrigated throughout their lifecycle with a 10-PFAS mixture (25-25,000 ppt) in a pulsed-chronic regime mimicking agricultural watering patterns. Early growth reductions were observed only at higher exposures (≥2500 ppt), with little inhibition at lower levels. All plants recovered by mid-season with no overt phytotoxicity. At maturity, reproductive output was enhanced, with bean counts and protein/carbohydrate content significantly increased, most notably at 25,000 ppt. Root transcriptome analysis revealed upregulation of aquaporins, nutrient transporters, and oxidative stress pathways, indicating coordinated shifts in water balance, metabolism, and defense. These responses align with hormesis, where early stress primes adaptive mechanisms enhancing later performance. PFAS accumulation showed distinct partitioning: short-chain PFAS, especially PFBA, dominated in beans (10.01-314.25 ng/g), while long-chain PFAS remained in roots. At the environmentally relevant 250 ppt treatment, bean PFAS concentrations were within a range where even modest dietary consumption could contribute to exceeding the European Food Safety Authority's tolerable weekly intake (4.4 ng/kg bw/week for select PFAS). While further work is needed to translate these values to dietary exposure scenarios, the results highlight the importance of considering crop resilience and food safety implications in PFAS-contaminated agricultural systems.

Per- and polyfluoroalkyl substances (PFAS) are detrimental to human and environmental health. Here, we discuss obstacles hindering PFAS biodegradation, addressing challenges from chemical and microbial ecotoxicological perspectives. We then highlight the unique eco-evolutionary landscapes of buried landfills and consider the importance of these underexplored xeno-ecological niches for promoting PFAS biodegradation.

Microwave irradiation, being an electromagnetic wave, facilitates volumetric heating through various dielectric heating modes such as dipolar polarization and ionic conduction. In this review, an attempt has been made to critically discuss various principles associated with microwave–material interactions. The review has given particular importance to recent developments in microwave-assisted material synthesis and processing of various materials such as metals, ceramics, polymers, nanoparticles, and food materials. The microwave method has various advantages over conventional heating methods in terms of reaction kinetics, product uniformity, and energy efficiency. The review also critically discusses some of the challenges faced by microwave–material interactions and how they can be addressed by adopting new strategies, such as hybrid heating and reactor innovations. In addition, future research directions have also been outlined to take microwave technologies to new heights in material processing.

Short-chain perfluoroalkyl substances (PFAS), such as perfluorobutanoic acid (PFBA), are increasingly detected in agricultural soils, irrigation water, and crop tissues, yet their biological effects at low, environmentally relevant concentrations remain poorly understood. Here, we investigated the dose-dependent effects of PFBA on growth, feeding, development, and gene expression in the fall armyworm (Spodoptera frugiperda). Across a broad concentration range, PFBA elicited a biphasic response characterized by low-dose stimulation and high-dose inhibition of larval growth. PFBA exposure across low concentrations (0.001-10 µg/g) enhanced early feeding and accelerated growth, leading to earlier attainment of developmental milestones, including reduced time to pupation and adult emergence. In contrast, higher concentrations suppressed growth. Transcriptomic analyses revealed that these contrasting phenotypes were underpinned by distinct, dose- and time-dependent transcriptional programs. Low-dose exposure induced a coordinated progression from early activation of structural and contractile pathways to enrichment of developmental and morphogenetic processes, consistent with accelerated maturation. In contrast, high-dose exposure triggered stress-associated transcriptional states, including activation of detoxification, oxidative stress, and neuronal signaling pathways, alongside suppression of endocrine and metabolic regulators. Together, these findings demonstrate that PFBA-induced hormesis reflects structured reprogramming of growth and developmental pathways rather than simple metabolic stimulation. By linking dose-resolved phenotypic responses with global transcriptomic organization, this study provides mechanistic insight into how short-chain PFAS can act as both modulators of biological performance and toxic stressors. Given the increasing prevalence of PFBA in agricultural systems, these results highlight the importance of incorporating non-monotonic dose-response relationships into ecological risk assessment and evaluating how PFAS exposure may influence pest dynamics in agroecosystems.