Search Results (23)

Wastewater-derived microplastics (WW-MPs) are increasingly recognised as reactive vectors for aromatic organic contaminants (AOCs), yet their role in contaminant fate remains insufficiently constrained. This review synthesises current knowledge on the transformation of microplastics in wastewater treatment plants, including fragmentation, oxidative ageing, additive leaching, and biofilm formation, and links these processes to changes in sorption capacity toward phenols, PAHs and their derivatives, and organochlorine pesticides (OCPs). We summarise the dominant adsorption mechanisms-hydrophobic partitioning, π-π interactions, hydrogen bonding, and electrostatic and, in some cases, halogen bonding-and critically evaluate how wastewater-relevant parameters (pH, ionic strength, dissolved organic matter, temperature, and biofilms) can modulate these interactions. Evidence in the literature consistently shows that ageing and biofouling enhance WW-MP affinity for many AOCs, reinforcing their function as mobile carriers. However, major gaps persist, including limited data on real wastewater-aged MPs, lack of methodological standardisation, and incomplete representation of ageing, competitive sorption, and non-equilibrium diffusion in existing isotherm and kinetic models. We propose key descriptors that should be incorporated into future sorption and fate frameworks and discuss how WW-MP-AOC interactions may influence ecological exposure, bioavailability, and risk assessment. This critical analysis supports more realistic predictions of AOC behaviour in wastewater environments. Full article

The growing demand for sustainable and cost-effective alternatives to synthetic nematicides has driven interest in naturally derived compounds with selective activity against plant-parasitic nematodes. In this study, we evaluated the bionematicidal potential of undecanoic acid, a naturally occurring medium-chain (C11) fatty acid, against two economically important root-knot nematodes: Meloidogyne ethiopica and M. graminicola. Direct contact bioassays demonstrated 100% mortality of both species within 24 h of exposure to a 1 mg/mL concentration, confirming strong and rapid nematicidal activity. In contrast, exposure of a non-target, the free-living soil nematode Cephalobus sp., resulted in only ca. 20% mortality, suggesting a favorable degree of selectivity toward phytoparasites. Additionally, environmental fate modeling indicated a predicted distribution of this compound of ca. 69% in soil, 28% in water, and 3% in air environmental compartments, consistent with its use as a soil-applied agent, while highlighting the need for environmental risk assessment under field conditions. As a naturally sourced compound, undecanoic acid offers advantages over synthetic nematicides, not only due to its biodegradability and potential reduced environmental impact, but also its lower cost compared to commercial pesticide active ingredients. The selective toxicity of undecanoic acid makes it a favorable candidate for integrated pest management programs, particularly in low-input or organic systems. These results underscore the potential of this naturally occurring fatty acid as an effective and sustainable tool for nematode control. Further studies on formulation optimization, persistence, and field efficacy will be needed to fully realize its application in agricultural systems. Full article

The fate and risk identification of cyantraniliprole (CYA) and lufenuron (LUF) in pak choi were systematically analyzed through an investigation comprising field trials, dissipation kinetics, and dietary risk assessment. Initially, field experiments across ten Chinese provinces revealed half-lives of 3.04–5.41 d for CYA and 2.02–5.13 d for LUF, with dissipation following single first-order (SFO) kinetics or double first-order in parallel (DFOP) kinetics. Terminal residues (<limit of quantification (LOQ) to 0.29 mg/kg) were below maximum residue limits. Dissipation rates were significantly influenced by temperature, climate, and crop growth stage. Additionally, the multidimensional dietary assessment using deterministic and probabilistic models revealed acceptable long-term risk levels for CYA and LUF among consumer groups (risk quotients < 28.4%). Overall, this first comprehensive study from cultivation to consumption provides crucial insights for rational pesticide use in pak choi. Full article

Phosphonate-based fungicides are believed to control fungal diseases while also supplying nutrients to plants. However, opinions differ on whether they truly serve as nutrients for plants, and the residues of their transformation products have not yet been thoroughly evaluated or mathematically characterized. To address this gap, this study analyzed data from a two-factorial experiment investigating the effects of Agrifos 400 (potassium phosphonate) application. The experiment involved two soil types: red basalt soil and an organically enriched soil. Three-month-old pepper plants (Piper nigrum L.) were treated with Agrifos at application intervals of 10 and 20 days. The soils were inoculated with pathogenic Pythium spp., known to cause root rot diseases in plants. The soil chemical concentrations were analyzed every ten days, while plant growth parameters (height and leaf numbers) were recorded weekly. A mathematical model describing the fate of Agrifos transformation products was developed and parameterized using this experimental data. The results from the two-month experiment indicated that Agrifos did not enhance plant growth during this period. However, it led to a dramatic increase in soil phosphate (PO₄³⁻) levels, which could pose environmental risks. Despite this, the developed mathematical model demonstrated strong explanatory power, accurately capturing the observed data trends. Consequently, future research should consider integrating this model into broader biogeochemical cycle simulations, particularly those that incorporate chemical transport through soil water. Such integration would support more accurate predictions of the long-term environmental impacts of phosphonate-based products like Agrifos. Full article

Halogenated benzaldehydes possess unique chemical properties that render them valuable in pharmaceutical synthesis, pesticide formulation, and dye production. However, thorough thermodynamic data for these compounds remain scarce. This study aims to fill this knowledge gap by investigating key physical properties of several halogenated benzaldehydes, namely 4-chlorobenzaldehyde, 4-bromobenzaldehyde, 2,3-dichlorobenzaldehyde, 2,4-dichlorobenzaldehyde, and 2,6-dichlorobenzaldehyde. The physical properties determined in this study include volatility, phase transitions, and water solubility, all of which are crucial for predicting the environmental fate of these compounds. The vapor pressures of both crystalline and liquid phases were measured using a reliable static method, allowing for the determination of standard molar enthalpies, entropies, and Gibbs energies of sublimation and vaporization, as well as their triple points. The melting temperature and molar enthalpy, along with the isobaric molar heat capacity of the crystalline phase, were assessed using differential scanning calorimetry. Water solubility was evaluated at 25 °C through the saturation shake-flask method, complemented by ultra-violet visible spectroscopy. By combining sublimation and solubility data, additional properties such as Gibbs energies of hydration and Henry’s law constants were derived. The experimental results were integrated into existing databases, enhancing the predictive models for properties including melting temperature, vapor pressure, solubility, Gibbs energy of hydration, and Henry’s constant. These findings significantly improve the environmental modeling capabilities, providing valuable insights into the mobility and fate of halogenated benzaldehydes in various environmental contexts. Full article

The Sea of Azov, an inland shelf sea bounding Ukraine and Russia, experiences the effects of ongoing and legacy pollution. One of the main contaminants of concern is the heavy metal mercury (Hg), which is emitted from the regional coal industry, former Hg refineries, and the historic use of mercury-containing pesticides. The aquatic biome acts both as a major sink and source in this cycle, thus meriting an examination of its environmental fate. This study collated existing Hg data for the SoA and the adjacent region to estimate current Hg influxes and cycling in the ecosystem. The mercury-specific model “Hg Environmental Ratios Multimedia Ecosystem Sources” (HERMES), originally developed for Canadian freshwater lakes, was used to estimate anthropogenic emissions to the sea and regional atmospheric Hg concentrations. The computed water and sediment concentrations (6.8 ng/L and 55.7 ng/g dw, respectively) approximate the reported literature values. The ongoing military conflict will increase environmental pollution in the region, thus further intensifying the existing (legacy) anthropogenic pressures. The results of this study provide a first insight into the environmental Hg cycle of the Sea of Azov ecosystem and underline the need for further emission control and remediation efforts to safeguard environmental quality. Full article

With projections suggesting an increase in the global use of neonicotinoids, contemporary farmers can get caught on the “pesticide treadmill”, thus creating ecosystem side effects. The aim of this study was to investigate the sorption/desorption behavior of acetamiprid, imidacloprid, and thiacloprid that controls their availability to other fate-determining processes and thus could be useful in leveling the risk these insecticides or their structural analogues pose to the environment, animals, and human health. Sorption/desorption isotherms in four soils with different organic matter (OC) content were modelled by nonlinear equilibrium models: Freundlich’s, Langmuir’s, and Temkin’s. Sorption/desorption parameters obtained by Freundlich’s model were correlated to soil physico-chemical characteristics. Even though the OC content had the dominant role in the sorption of the three insecticides, the role of its nature as well as the chemical structure of neonicotinoids cannot be discarded. Insecticides sorbed in the glassy OC phase will be poorly available unlike those in the rubbery regions. Imidacloprid will fill the sorption sites equally in the rubbery and glassy phases irrespective of its concentration. The sorption of thiacloprid at low concentrations and acetamiprid at high concentrations is controlled by hydrophilic aromatic structures, “trapping” the insecticides in the pores of the glassy phase of OC. Full article

The constant influx of pesticides into soils is a key environmental issue in terms of their potential retention in the soil, thus reducing their negative impact on the environment. Soil organic matter (SOM) is an important factor influencing the environmental fate of these substances. Therefore, the aim of this research was to assess the chemical behavior of pesticides (flufenacet, pendimethalin, α-cypermethrin, metazachlor, acetamiprid) toward stable soil humin fractions (HNs) as a main factor affecting the formation of non-extractable residues of agrochemicals in soil. This research was conducted as a batch experiment according to OECD Guideline 106. For this purpose, HNs were isolated from eight soils with different physicochemical properties (clay content = 16–47%, pH_KCl = 5.6–7.7, TOC = 13.3–49.7 g·kg⁻¹, TN = 1.06–2.90 g·kg⁻¹, TOC/TN = 11.4–13.7) to reflect the various processes of their formation. The extraction was carried out through the sequential separation of humic acids with 0.1 M NaOH, and then the digestion of the remaining mineral fraction with 10% HF/HCl. The pesticide concentrations were detected using GC-MS/MS. The pesticides were characterized based on the different sorption rates to HNs, according to the overall trend: metazachlor (95% of absorbed compound) > acetamiprid (94% of absorbed compound) > cypermethrin (63% of partitioning compound) > flufenacet (39% of partitioning compound) > pendimethalin (28% of partitioning compound). Cypermethrin and metazachlor exhibited the highest saturation dynamic, while the other agrochemicals were much more slowly attracted by the HNs. The obtained sorption kinetic data were congruous to the pseudo-first-order and pseudo-second-order models related to the surface adsorption and interparticle diffusion isotherm. The conducted research showed that the processes of pesticide sorption, apart from physicochemical phenomena, are also affected by the properties of the pollutants themselves (polarity, K_OC) and the soil properties (SOM content, clay content, and pH_KCl). Full article

This critical review examines the release of pesticides from agricultural practices into the air, with a focus on volatilization, and the factors influencing their dispersion. The review delves into the effects of airborne pesticides on human health and their contribution to anthropogenic air pollution. It highlights the necessity of interdisciplinary research encompassing science, technology, public policy, and agricultural practices to effectively mitigate the risks associated with pesticide volatilization and spray dispersion. The text acknowledges the need for more research to understand the fate and transport of airborne pesticides, develop innovative application technologies, improve predictive modeling and risk assessment, and adopt sustainable pest management strategies. Robust policies and regulations, supported by education, training, research, and development, are crucial to ensuring the safe and sustainable use of pesticides for human health and the environment. By providing valuable insights, this review aids researchers and practitioners in devising effective and sustainable solutions for safeguarding human health and the environment from the hazards of airborne pesticides. Full article

The agricultural industry uses substantial amounts of water (the highest in the world) mostly for irrigation purposes. Rapid population growth and, consequently, growing demand for food have increased the use of pesticide to have higher yield for crops and other agricultural products. Wastewater generated as a result of excessive use of pesticides/herbicides in agricultural industry is becoming a global issue specifically in developing countries. Over 4,000,000 tons of pesticides are currently used in the world annually and high concentrations above their threshold limits have been detected in water bodies worldwide. The generated wastewater (contaminated with pesticides) has negative impacts on human health, the ecosystem, and the aquatic environment. Recently, biodegradable and biocompatible (including plant-based) pesticides have been introduced as green and safe products to reduce/eliminate the negative impacts of synthetic pesticides. Despite positive advantages of biopesticides, their use is limited due to cost and slow interaction with pests compared to chemical pesticides. Pesticides may also react with water and constituents of soil resulting in formation of intermediates having different physical and chemical properties. Diffusion, dispersion, and permeation are main mechanisms for transfer of pesticides in soil and water. Pesticides may degrade naturally in nature; however, the time requirement can be very long. Many mathematical models have been developed to simulate and estimate the final fate of pesticides in water resources. Development of new technologies and environmentally friendly pesticides to reduce water contamination is becoming increasingly important. Full article

Microplastics (MP) are spread into all ecosystems and represent a threat to the equilibrium of the environment and human health, not only due to their intrinsic characteristics but also to their action as effective carriers of contaminants, such as pesticides, pharmaceuticals, polychlorinated biphenyls and polycyclic aromatic hydrocarbons. The pesticide α-endosulfan is persistent and spread in the environment. The MP are another possible way of dissemination to be considered in the fate of this pesticide. The adsorption dynamics of α-endosulfan by six different MP (low-density polyethylene—LDPE, polyethylene-co-vinyl acetate, unplasticized polyvinyl chloride, polyamide 6, polystyrene granule, polypropylene granule) with different sizes/shapes and chemical compositions were evaluated. The most critical situation was identified for the system LDPE (particle size < 300 μm). Equilibrium studies (48 h equilibrium time) were performed for distilled, tap and filtered river water. Based on the Langmuir model parameters, the highest maximum adsorption capacity was obtained for distilled water, followed by filtered river and tap waters (i.e., 366 ± 39, 247 ± 38, 157 ± 22 μg/g). The obtained results demonstrate the important role that microplastics may have in the fate and transport of pesticides and their potentially harmful effect on the environment, which requires further investigation. Full article

The aim of this study was to estimate bentazone’s potential to leach to groundwater in the Arenosols developed from sand, Luvisols developed from loamy sand or sandy loam, and Luvisols or Cambisols developed from loess, and to identify the major factors influencing bentazone’s fate in the soils. Potato and maize cultivations were simulated using the FOCUS PELMO 5.5.3 pesticide leaching model. The amount of bentazone reaching groundwater was highly sensitive to degradation parameters, water-holding capacity, evapotranspiration, organic carbon content, and pH. The highest bentazone concentrations in percolate were noted in Arenosols. The risk of bentazone concentration exceeding 0.1 μg/L was low only in Arenosols with high organic carbon content (3.0% for topsoil or higher). In Luvisols developed from loamy sand or sandy loam, the estimated bentazone concentrations in percolate were highly dependent on the climate. In Luvisols or Cambisols developed from loess, concentrations of >0.1 μg/L were the least likely due to the high water-holding capacity and high organic carbon content of these soils. The study also revealed that the FOCUS Hamburg scenario, representing the coarsest soils in the European Union with relatively low organic carbon content, does not reflect the leaching potential of Arenosols and Luvisols. Full article

Assessing the risk of using pesticides for the environment in general, and for groundwater in particular, necessitates prediction of pesticide migration. For this purpose, mathematical models of pesticide behavior are utilized, which must be parameterized and calibrated based on experimental data to make them perform properly. The behavior of the pesticide cyantraniliprole was examined in a long-term lysimetric experiment. The MACRO 5.2 dual porosity model was calibrated based on the percolate and the levels of pesticides in the soil profile and percolate. Despite employing experimentally verified soil parameters and pedotransfer functions (PTF), the model must be calibrated for percolation. This is due to the model’s properties as well as the complexity of the soil as an object of study, and its pore space, which is subject to daily and annual fluctuations. It is the parameters that describe the structure of the pore space that need to be calibrated. Calibrating for pesticide concentrations required a minor revision of the sorption and transformation rates, as well as an increase in the dispersivity and ASCALE values. Full article

Organic wastes applied as composted amendments may improve the quality of degraded soils and modify the fate of pesticides. This work has set out to study the dissipation kinetics of the herbicides chlorotoluron and flufenacet during their second-year application in field experimental plots with a sandy-loam agricultural soil without amendment (S) and amended with spent mushroom substrate (S + SMS) or green compost (S + GC). The SMS and GC were applied to the soil during the previous winter’s wheat crop campaign (1 year before the second herbicide application) at rates of 140 and 85 t ha⁻¹ (dry weight basis), respectively. The experiment involved randomized complete blocks with plots of 81 m², including three replicates per soil treatment. Surface soils were sampled after herbicide application for 225 days, and herbicide residues in the soil samples were determined by HPLC-MS. The dissipation curves of both herbicides for the three soil treatments were better fitted to the first order multi-compartment (FOMC) kinetic model. The dissipation rates of the most hydrophobic herbicide, flufenacet, were slower than those for chlorotoluron in both unamended and amended soils. The half-life (DT₅₀) values ranged between 20.7 to 41.1 days for chlorotoluron, and 42.9 to 75.6 days for flufenacet, and they followed the order S > S + SMS > S + GC. The DT₅₀ values of chlorotoluron were close for S + SMS and S + GC, and the DT₅₀ of flufenacet for S was similar to that for S + SMS. These DT₅₀ values decreased up to four times with respect to those calculated after the first application indicating an accelerated dissipation of the herbicides after the second application especially in amended soil in comparison with unamended soil. The persistence of chlorotoluron and flufenacet in an agricultural soil was modified by the effect of the organic amendments, weather conditions, and possibly the repeated application of the compounds under real field conditions. Full article

The management of large volumes of organic residues generated in different livestock, urban, agricultural and industrial activities is a topic of environmental and social interest. The high organic matter content of these residues means that their application as soil organic amendments in agriculture is considered one of the more sustainable options, as it could solve the problem of the accumulation of uncontrolled wastes while improving soil quality and avoiding its irreversible degradation. However, the behavior of pesticides applied to increase crop yields could be modified in the presence of these amendments in the soil. This review article addresses how the adsorption–desorption, dissipation and leaching of pesticides in soils is affected by different organic residues usually applied as organic amendments. Based on the results reported from laboratory studies, the influence on these processes has been evaluated of multiple factors related to organic residues (e.g., origin, nature, composition, rates, and incubation time of the amended soils), pesticides (e.g., with different use, structure, characteristics, and application method), and soils with different physicochemical properties. Future perspectives on this topic are also included for highlighting the need to extend these laboratory studies to field and modelling scale to better assess and predict pesticide fate in amended soil scenarios. Full article