Operator Dermal Exposure to Pesticides in Tomato and Strawberry Greenhouses from Hand-Held Sprayers

Protection of greenhouse crops in southern Italy usually requires 15–20 phytosanitary treatments per year, with volume rates in the range of 1000–2000 L ha1, depending on the plant growth stage. The most widespread sprayers are hand-held, high-pressure devices, which may expose operators to high levels of pesticides. This paper, also with the aim to lead toward a more sustainable use of greenhouses in agricultural productions, including some aspects of workers’ safety, reports the results of experimental tests aimed at measuring the amount of the mixture deposited on the worker’s body (potential dermal exposure, PDE) during pesticide applications to tomato and strawberry plants in a protected environment. Experimental tests on tomatoes were carried out taking into account two plant growth stages (flowering and senescence), two types of spray lance, two working pressures (1 and 2 MPa), and two walking directions (forwards and backwards). Those on the strawberries were carried out at the maturity of the fruit growth stage, comparing two hand-held sprayers (a standard spray gun and a short hand-held spray boom equipped with two nozzles) and working according to the common practice: forwards movement of the operator and high pressure (2 MPa). The results showed that with the tomato plants, the most important factor in reducing the deposit on the operator was the walking direction: on average, the PDE was 718 mL per 1000 L of the sprayed mixture (0.72h) while walking forwards and 133 mL (0.13h) while walking backwards. The reduction factor ranged from 3.0 at the flowering growth stage to 7.2 at the senescence growth stage. With respect to the strawberry plants, the PDE was significantly higher when the operator used the short hand-held spray boom (887 mL per 1000 L of the sprayed mixture, equivalent to 0.89h), rather than the spray gun (344 mL, 0.34h). In both cases, the most exposed body parts were the lower limbs, which accounted for 89–94% of the total PDE

Study of the correlation between foliar and patternator deposits in a “Tendone” vineyard

The correct sprayer setting, with the appropriate selection of the operative parameters such as forward speed, airflow rate, volume rate, and distribution profiles according to the geometrical and morphological features of the target, is a key point in all phytosanitary treatments.  The assessment of distribution profiles usually requires the use of patternators, able to intercept the spray jet and then to provide information useful for sprayer calibration.  The present paper analyses the correlations between foliar deposits measured during treatments in a “tendone” vineyard and the quantities of mixture intercepted by a patternator (distribution profile) used during the preliminary calibration of the sprayer, assuming the Leaf Area Index (LAI) of the vineyard as reference.  All correlations between patternator deposits and LAI of the vineyard and between foliar deposits and patternator deposits were statistically significant, so demonstrating the importance of patternators as powerful tools during the sprayer calibration process

Foliar spray deposition in a “tendone” vineyard as affected by airflow rate, volume rate and vegetative development

The objective of this study was the evaluation of the effect of airflow rate and volume rate on foliar spray deposition in a “tendone” vineyard using an air-assisted sprayer with two counter-rotating fans and anterior intake. Experimental tests were carried out considering two airflow rates (2.43 and 5.71 m3 s−1), two volume rates (335 and 625 L ha−1) and keeping the forward speed constant (1.1 m s−1). To take into account the effect of vegetative development of the vineyard, experiments were replicated in two phenological stages (full flowering and berry touch), characterised by different Leaf Area Indices (2.21 and 5.83). The sprayer was calibrated using a patternator purposely designed for “tendone” vineyards, assuming the vineyard Leaf Area Index (LAI) pattern as a reference. Sprayer calibration was accomplished achieving a close correlation between LAI pattern and the quantity of liquid intercepted by the patternator (coefficients of linear correlation ranged from 0.95 to 0.99, all significant at p < 0.05). Measurements on vines showed that volume rate did not affect foliar spray deposition at either phenological stage, whereas airflow rate had an opposite effect at the two phenological stages. At full flowering, the increase in airflow rate produced a significant decrease in foliar deposit (from 0.986 to 0.693 μL cm−2 on the most exposed vegetation, −30%); on the contrary, at the berry touch growth stage the increase in airflow rate produced a significant increase in foliar deposits (from 0.339 to 0.484 μL cm−2, +43%)

Study of the correlation between foliar and patternator deposits in a “Tendone” vineyard

The correct sprayer setting is a key point in all phytosanitary treatments to optimise efficacy and reduce environmental impact. The goal can be achieved with the appropriate choice of the operative parameters such as forward speed, airflow rate, volume rate, working pressure and nozzle types. Moreover, sprayer calibration requires adapting the distribution profile, i.e. the spatial distribution of the sprayed mixture, according to the geometrical and morphological features of the target. Distribution profiles may be assessed by using special patternators able to intercept the spray jet. The present paper analysed the correlations between distribution profiles, leaf area index (LAI) and foliar deposits measured during treatments in a “tendone” vineyard. All correlations between patternator deposits and LAI of the vineyard and between foliar deposits and patternator deposits were statistically significant, with determination coefficients ranging from 0.724 to 0.999. These results demonstrate the importance of patternators as powerful tools during the sprayer calibration process

Improvements in citrus packing lines to reduce the mechanical damage to fruit

Citrus fruits destined to the fresh market are subject to several treatments in packing lines with the aim of lengthen shelf-life, increase commercial value, and comply with the rules on marketing. During the treatments, fruits collide with each other and with components of the machines and undergo mechanical damage that can be very serious. Therefore, operators make changes to the machines in order to reduce number and intensity of impacts. This paper reports the results of a study on the impacts suffered by oranges during packing operations, carried out by using an instrumented sphere IS100. Experimental measurements were conducted in a packing house equipped with two packing lines, where they were both traditional and innovative machines (regarding the empting and the filling of the bins, the release of the fruits from the sizing machines, the transfer of the fruits between belt conveyors), specifically designed to reduce the mechanical impacts to the fruits. The results showed that the innovations were effective in reducing the intensity of the impacts, expressed in terms of acceleration. The maximum acceleration was always lower (from 47 to 83 %) with respect to the conventional machines, whereas the average number of impacts per replicate was lower in the sizing machines (-6 %) and during the emptying of the bins (-36 %), but was higher during the transfer of the oranges between belt conveyors (+33 %) and during the filling of the bins (+73 %). The increase in the average number of impacts depends from the fact that the innovative systems "accompany" the fruits towards the exit, causing a greater number of impacts of lower intensity

Operator Dermal Exposure to Pesticides in Tomato and Strawberry Greenhouses from Hand-Held Sprayers

Protection of greenhouse crops in southern Italy usually requires 15–20 phytosanitary treatments per year, with volume rates in the range of 1000–2000 L ha−1, depending on the plant growth stage. The most widespread sprayers are hand-held, high-pressure devices, which may expose operators to high levels of pesticides. This paper, also with the aim to lead toward a more sustainable use of greenhouses in agricultural productions, including some aspects of workers’ safety, reports the results of experimental tests aimed at measuring the amount of the mixture deposited on the worker’s body (potential dermal exposure, PDE) during pesticide applications to tomato and strawberry plants in a protected environment. Experimental tests on tomatoes were carried out taking into account two plant growth stages (flowering and senescence), two types of spray lance, two working pressures (1 and 2 MPa), and two walking directions (forwards and backwards). Those on the strawberries were carried out at the maturity of the fruit growth stage, comparing two hand-held sprayers (a standard spray gun and a short hand-held spray boom equipped with two nozzles) and working according to the common practice: forwards movement of the operator and high pressure (2 MPa). The results showed that with the tomato plants, the most important factor in reducing the deposit on the operator was the walking direction: on average, the PDE was 718 mL per 1000 L of the sprayed mixture (0.72‰) while walking forwards and 133 mL (0.13‰) while walking backwards. The reduction factor ranged from 3.0 at the flowering growth stage to 7.2 at the senescence growth stage. With respect to the strawberry plants, the PDE was significantly higher when the operator used the short hand-held spray boom (887 mL per 1000 L of the sprayed mixture, equivalent to 0.89‰), rather than the spray gun (344 mL, 0.34‰). In both cases, the most exposed body parts were the lower limbs, which accounted for 89–94% of the total PDE

Ultra-high performance separation of basic compounds on reversed-phase columns packed with fully/superficially porous silica and hybrid particles by using ultraviolet transparent hydrophobic cationic additives

The use of the tetrabutylammonium additive was investigated in the ultra-high performance reversed-phase liquid chromatographic elution of basic molecules of pharmaceutical interest. When added to the mobile phase at low pH, the hydrophobic tetrabutylammonium cation interacts with the octadecyl chains and with the residual silanols, thus imparting a positive charge to the stationary phase, modulating retention and improving peak shape of protonated basic solutes. Two sources of additive were tested: a mixture of tetrabutylammonium hydroxide/trifluoroacetic acid and tetrabutylammonium hydrogen sulfate. Retention and peak shape of 11 basic pharmaceutical compounds were evaluated on commercially available ultra-fast columns packed with octadecyl stationary phases (Ascentis Express C18 2.0 mu m, Acquity BEH C18 1.7 mu m, Titan C18 1.9 mu m). All columns benefit from the use of additive, especially tetrabutylammonium hydrogen sulfate, providing very symmetric peaks with reasonable retention times. Focusing on the probe compounds amitriptyline and sertraline, efficiency and asymmetry values were investigated at increasing retention factor. The trend is very different to that obtained in reversed-phase conditions and the effect lies in the complex molecular interaction mechanisms based on hydrophobic and ion exchange interactions as well as electrostatic repulsion

Separation of Monosaccharide Anomers on Photo-Click Cysteine-Based Stationary Phase: The α/β Interconversion Process Studied by Dynamic Hydrophilic Liquid Chromatography

In High-Performance Liquid Chromatography (HPLC), the separation of reducing sugars can typically show three possible typologies of chromatographic profiles (i.e., single peak, two resolved peaks and two peaks interconnected by a plateau) due to the rate at which the relevant α/β anomers interconversion (anomerization) can take place in relation to their elution-time. By analyzing these chromatographic profiles, thermodynamic and kinetic properties of anomerization phenomenon can be extrapolated. In this work we studied the anomerization of some monosaccharides by using a recently developed photo-click cysteine-based stationary phase through dynamic hydrophilic interaction liquid chromatography (D-HILIC) conditions. In the 5–25 °C temperature range, the ΔG#α→β and ΔG#β→α barriers were found to achieve values within the interval 21.1/22.2 kcal/mol for glucose, with differences between α→β and β→α reactions of about 0.4 kcal/mol. For xylose, in the same temperature range, the ΔG#α→β and ΔG#β→α barriers are between 20.7 to 21.5 kcal/mol, with differences between α→β and β→α reactions of about 0.2 kcal/mol. The experimental data are in agreement with those reported in literature, confirming the this new stationary phase using HILIC conditions is a robust platform to measure kinetic and thermodynamic properties of the isomerization reaction

Expanding the Use of Dynamic Electrostatic Repulsion Reversed-Phase Chromatography: An Effective Elution Mode for Peptides Control and Analysis

Bioactive peptides are increasingly used in clinical practice. Reversed-phase chromatography using formic or trifluoroacetic acid in the mobile phase is the most widely used technique for their analytical control. However, sometimes it does not prove sufficient to solve challenging chromatographic problems. In the search for alternative elution modes, the dynamic electrostatic repulsion reversed-phase was evaluated to separate eight probe peptides characterised by different molecular weights and isoelectric points. This technique, which involves TBAHSO4 in the mobile phase, provided the lowest asymmetry and peak width at half height values and the highest in peak capacity (about 200 for a gradient of 30 min) and resolution concerning the classic reversed-phase. All analyses were performed using cutting-edge columns developed for peptide separation, and the comparison of the chromatograms obtained shows how the dynamic electrostatic repulsion reversed-phase is an attractive alternative to the classic reversed-phase

Assessing the performance of new chromatographic technologies for the separation of peptide epimeric impurities: the case of Icatibant

: The biopharmaceutical industry faces the challenge of efficiently characterising impurity profiles of therapeutical peptides, also due to their complex polar and ionisable attributes. This research explores the potential of advanced chromatographic techniques to address this challenge. The study compares dynamic electrostatic repulsion reversed phase (d-ERRP) to its counterparts (static ERRP and ion pair reversed phase IP-RP) in analysing Icatibant and its elusive epimeric impurity, [L-Arg]1-Icatibant and highlights its exceptional capabilities in generating symmetric peaks, mitigating the common tailing phenomenon, and serving as a steadfast guardian of column longevity. The result highlights d-ERRP as a pioneering tool in the domain of liquid chromatography, fostering its role as a reference technique for the analysis of therapeutic peptides