Plant protection products (pesticides) are used throughout the world in the form of various types, such as insecticides, fungicides, herbicides etc. High Density Polyethylene is the principal ...material that those containers are made of. The aim of the study was to determine the factors that statistically affect the generation of the resulting wasted plastic pesticide containers after pesticide application. The objective was to develop a mathematical model to describe the generation rate of wasted plastic pesticide containers as a function of certain parameters. 603 data series were recorded based on information from 106 farmers in Greece and nineteen (19) parameters were initially included as potential predictors. Each farmer filled up questionnaires and provided data for more than one type of crops. Data were obtained from six Greek prefectures. Empirical models were developed for all pesticides through linear regression. The cultivated area (m2), the type of crop (perennial/annual, irrigated/dry) and the type of pesticide application (on soil, on foliage) were the statistically significant parameters to affect generation rates. Eighteen (18) farmers provided 56 (new) observations to validate the models. Two of the four models are reliable due to their low validation errors and should be ideally used for crop areas above 58,000 m2. The total wasted plastic pesticide containers generation rate in Greece was estimated to be 0.028 kg farmer−1 y−1 1000 m−2. Modeling results can aid to predict the generation rate of wasted pesticide plastic containers at a regional and national level so that to properly design their management systems.
Peas are among the most popular leguminous plants, consumed by both humans and animals in large quantities. Pesticides are widely used globally to increase pea yield, and as a result, pesticide ...residues can be taken up by pea plants and bioaccumulate in their fruits, including peas and pods. However, there is a lack of modeling approaches available to predict residue concentrations in peas. To address this issue, a pod fruit model (specifically designed for neutral organic compounds) was proposed to simulate the bioaccumulation process of pesticide residues in pea plants, which was developed by modifying a peel-like uptake model. The simulation results, based on green pea as the modeling demonstration, reveal that moderately-lipophilic pesticides (i.e., log KOW around 3) have higher simulated concentrations in peas at harvest compared to hydrophilic (i.e., log KOW less than 0) or highly-lipophilic (i.e., log KOW over 5) pesticides, which is due to the enhanced uptake process of moderately-lipophilic compounds in the pod-pea system, such as their ability to penetrate the pod cuticle and be transported via phloem sap. The sensitivity test and variability analysis conducted in this study revealed that the degradation kinetics, including metabolism, hydrolysis, and photolysis, had a significant impact on moderately-lipophilic pesticides due to their high simulated concentrations in the pea plant. This can result in substantial loss of residue mass via degradation. The validation of the model demonstrated that the simulation results, specifically residue concentrations in the fruit, were consistent with the harvested data. However, some inconsistency was observed immediately after pesticide application, which could be attributed to plant growth dynamics and initial surface mass distributions. The proposed pod fruit model provides new insights into the bioaccumulation process of pesticide residues in pea plants and enables high-throughput simulations of residue concentrations at harvest. To enhance the performance of the pod fruit model, future research should consider plant growth dynamics, plant uptake of ionizable compounds, and initial mass distribution functions.
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•A pod fruit model offers new insights into pesticide bioaccumulation in pea plants.•The degradation kinetics are shown to play a vital role in the simulation results.•The model could be useful for high-throughput pesticide screening in pea plants.
•First use of comprehensive dataset for activities of professional pesticide operators•Operator exposures compared for three countries and arable and orchard systems•Small number of applications in ...all systems with estimated exposure>safety level•Risks in Greece driven by use of wettable powder formulations•Risks in the UK driven by large areas of land treated per day
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This study investigates how field practices in handling and applying pesticides influence the long-term patterns of professional agricultural operators' exposure to pesticides. It presents the first use of a comprehensive pesticide application dataset collected on behalf of the European Food Safety Authority with 50 operators selected to cover arable and orchard cropping systems in Greece, Lithuania and the UK. Exposure was predicted based on the harmonised Agricultural Operator Exposure Model (AOEM) and compared with Acceptable Operator Exposure Levels (AOELs). The amount of pesticides handled by individual operators across a cropping season was largest in the UK arable and orchard systems (median 580 and 437kg active substance, respectively), intermediate for the arable systems in Greece and Lithuania (151 and 77kg, respectively), and smallest in the Greek orchard system (22kg). Overall, 30 of the 50 operators made at least one application within a day with predicted exposure greater than the AOEL. The rate of AOEL exceedance was greatest in the Greek cropping systems (8 orchard operators, 2.8–16% of total applications; 7 arable operators, 1.1–14% of total applications), and least for the Lithuanian arable system (2 operators, 2.9–4.5% of total applications). Instances in Greece when predicted exposure exceed the AOEL were strongly influenced by the widespread use of wettable powder formulations (>40% of the total pesticide active substance handled for 11 of the 20 Greek operators). In contrast, the total area of land treated with an active substance on a single day was more important in the UK and Lithuania (95th percentile observed value was 132 and 19haday−1 for UK arable and orchard systems, respectively). Study findings can be used to evaluate current assumptions in regulatory exposure calculations and to identify situations with potential risk that require further analysis including measurements of exposure to validate model estimations.
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•Three-dimensional crops could benefit of drone technology towards sustainability.•Drift with autonomous UAV sprayer in comparison with conventional terrestrial spraying.•Using ...technology for efficient farm practices.
The demands of a growing population and a developing global economy will require an increase in agricultural yield of 70% over the next 30 years. However, achieving this goal is only possible with a sustainable intensification of agricultural systems. Spraying drones are one of the available technologies that could help meet this goal. Presently, the use of spraying drones is limited by both the legal framework and the lack of scientific knowledge about the drift they generate compared to conventional terrestrial spraying platforms. However, the flexibility that spraying drones provide, their characteristic vertical spraying, and the downwash airflow produced by the rotors might reduce drift. This study aimed to compare the drift generated by a conventional orchard sprayer to that generated by a spraying drone in a commercial superhigh-density olive orchard. Trials to assess the sedimented drift of both spraying platforms were conducted in the South Iberian Peninsula in 2022. Our results show that the drone sprayer required less than half the distance to sediment 90% of the sprayed volume compared to a conventional mist blower.
Progress in the reduction of environmental and health risks of PPPs (plant protection products) using Integrated Pest Management (IPM) in the EU needs to be gauged. Here, we report, for the first ...time, the exact quantities of PPP used in carrot, potato, swede, and fresh pea production in southwestern Finland from 2003 to 2019. Fresh peas and swede represent exceptionally low or decreasing use of PPPs, respectively. The number of treatments per field showed an increasing trend for fungicides used on potato, despite per unit area treatments have not increased. Furthermore, for carrots, insecticide and herbicide spray frequencies increased more than treatment volumes. The results of this study form a basis for analyzing ecotoxicological risks of PPP use in the studied crops because usage and spray frequencies alone do not convey the risk levels accurately. Research needs to be continued to better guide the recording of farmers’ plant protection activities and corresponding analysis to verify the impacts of IPM implementation.
The increasing demand for optimizing the use of agricultural resources will require the adoption of cutting-edge technologies and precision farming management. Unmanned Aerial Vehicle (UAV) sprayers ...seem promising due to their potential to perform precision or spot spraying, particularly in woody crop environments where total surface spraying is unnecessary. However, incorporating this technology is limited by the lack of scientific knowledge about the environmental risks associated with UAV sprayers and the strict legal framework. Nonetheless, these spraying systems' characteristic downwash airflow and the limited swath width can potentially mitigate drift in hedgerow crops. During our study we performed comparative studies aimed to compare the airborne drift, soil, and crop depositions between a conventional orchard sprayer and a UAV sprayer in a commercial superhigh-density orchard in the South Iberian Peninsula in 2022. Our findings reveal that, in superhigh-density olive orchards, the UAV sprayer presents a substantial reduction in airborne drift, while soil depositions showed no significant differences compared to those of a conventional terrestrial orchard sprayer. Crop depositions were significantly lower when utilizing the UAV sprayer. These results suggest that introducing UAV spraying technology in Mediterranean agricultural systems, under specific scenarios, can effectively reduce the environmental impact of crop spraying and encourage the responsible use of plant protection products (PPPs).
To assess potential aquatic pesticide risks, environmental monitoring strategies often focus on water and sediment. However, knowledge gaps with regard to the pollution status of organic matrices ...important for the structure and functioning of aquatic ecosystems do exist. The present study assessed the dissipation of the triazole fungicide tebuconazole (TEB; KOW = 5.01 × 103) and the pyrethroid insecticide etofenprox (ETO; KOW = 7.94 × 106) as model hydrophobic pesticide compounds among aquatic plants, vertical layers of allochthonous leaf litter, and detritus within flow-through outdoor stream mesocosms. During a 3-h pesticide exposure and a subsequent 24-h post-exposure period, retention was higher for ETO (max concentration: Myriophyllum spicatum > Elodea nuttallii > Ranunculus fluitans > Potamogeton perfoliatus ≫ leaf litter > detritus) and depended amongst other factors on surface area, while in the water compartment the pesticides reached concentration levels < LOQ 2 h after exposure. Desorption was observed for both pesticides in plants, and for TEB in detritus, while in leaves the ETO levels even increased over time, suggesting leaf litter to be a suitable additional sampling matrix for transient hydrophobic pesticide peaks, yet also a potential source of contamination for invertebrate shredders. The upper layer of leaf material contained higher ETO levels than those situated further in the sediment, which implies short-term positive effects for species inhabiting the deeper leaf layers, yet again pinpoints to a potential pesticide exposure pathway via organic matter in aquatic systems.
•In low-flow aquatic systems (e.g. creeks, streams, ditches), plants act as transient sink for hydrophobic pesticides.•Water-phase pesticide exposure leads to a decreasing concentration gradient along the vertical layers of leaf packages.•For benthic invertebrates, leaf layers may be protective from peak pyrethroid levels for a certain time period.•Leaf litter is a matrix capable of integrating for a certain time period pollution of previous pesticide exposure peaks.
The European Water Framework Directive requires surface water bodies to have a good chemical and ecological status. Although relatively few pesticides are included in the list of priority pollutants, ...they pose, due to their intrinsic biological activity, a significant risk for the integrity of aquatic ecosystems. In this context, the pesticide (up to 128 pesticides including some transformation products) exposure pattern in four agricultural streams and two rivers was determined from 2002 to 2011 under the umbrella of the Swedish national monitoring program employing time-proportional and grab sampling strategies, respectively. After transforming the measured pesticide concentrations into toxic units, the European Uniform Principles for algae (chronic), invertebrates and fish (both acute), which are partly employed as benchmark for pesticide regulation, were only occasionally (<2%) exceeded. Moreover, this evaluation showed no long-term trends over the years. However, recent publications suggested that those thresholds are not protective for ecosystem structure and function, indicating a risk of up to 20% and 35% of the samples from the agricultural streams and the rivers, respectively. Moreover, the monitoring data show a continuous but rather low toxic potential of pesticides for all three trophic levels throughout the year, which suggests pesticides as an evolutionary force in agriculturally impacted aquatic ecosystems. However, the flow-triggered sampling, which was implemented as an additional sampling strategy in one of the agricultural streams starting in 2006, displayed an up to 7-fold underestimation of the maximum concentration in terms of toxic units for daphnids and fish during run-off events. The present study thus underpins that the optimal sampling design for pesticide monitoring strongly depends on its overall purpose. If the long-term exposure pattern is of concern a time-proportional composite sampling strategy is recommended, while for an assessment of peak exposures a flow-event-triggered high-resolution sampling strategy is superior.
•Pesticide concentrations in Swedish streams rarely exceed European Uniform Principles.•A risk for aquatic ecosystem structure and function can nonetheless be anticipated.•Time-proportional weekly samples inform about the long-term average exposure pattern.•Flow proportional event-triggered samples capture peak exposure and duration.
Pesticides play an important role in providing high crop yields by minimising the risks associated with pests but some of the sprayed product may move beyond the intended target and result in drift. ...Modelling approaches can help understand the behaviour of spray drift using computer simulations. However, modelling drift from orchard spraying presents particular challenges: (1) the moving spray interacts with the canopy before drifting outside the target area; (2) the vertical wind profile in the orchard is different to neighbouring fields where there is different vegetation; (3) the moving air jet from the air-assistance cannot be ignored because the airspeed of the fan is usually higher than the wind speed.
This work presents a three-dimensional (3D) computational fluid dynamics (CFD) model of spray drift from orchard sprayers that considers tree architecture, canopy wind flow and the movement of the sprayer to calculate sedimenting and airborne drift; thus tackling the challenges listed above. The model was validated against drift measurements from an apple orchard with different nozzles arrangements. The model was then used to evaluate the effect of drift reducing nozzles and fan airspeed on drift. The model predicted that drift reducing nozzles reduced the drifting distance by 50%, but increased near-tree ground deposition. This increase in ground deposition can be avoided whilst retaining the reduction in the drifting distance, by using a combination of drift reducing and standard nozzles. A reduced sprayer airflow can further reduce drift.
•A CFD model of drift from orchard sprayers was developed and validated.•The model is used to analyse effect of nozzle arrangement and fan speed on drift.•Drift reducing nozzles reduce drift but increase near-tree ground deposition.•Drift reducing and standard nozzles together can reduce near-tree ground deposition.
Published literature has been reviewed in order to (a) explore the (potential) applications of nanotechnology in pesticide formulation, (b) identify possible impacts on environmental fate, and (c) ...analyze the suitability of current exposure assessment procedures to account for the novel properties of nanopesticides within the EU regulatory context. The term nanopesticide covers a wide variety of products and cannot be considered to represent a single category. Many nanoformulations combine several surfactants, polymers, and metal nanoparticles in the nanometer size range. The aims of nanoformulations are generally common to other pesticide formulations, these being to increase the apparent solubility of poorly soluble active ingredients, to release the active ingredient in a slow/targeted manner and/or to protect against premature degradation. Nanoformulations are thus expected to (a) have significant impacts on the fate of active ingredients and/or (b) introduce new ingredients for which the environmental fate is still poorly understood (e.g., nanosilver). Therefore, it seems that adaptations of current exposure assessment approaches will be necessary, at least for some nanopesticides. The present analysis provides a useful framework to identify priorities for future research in order to achieve more robust risk assessments of nanopesticides.
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