Elimination Of Pesticides Research Articles

Biodegradation of Cyromazine by Mycobacterium sp. M15: Performance, Degradation Pathways, and Key Enzymes.

Cyromazine, a triazine insecticide, raises food safety concerns due to residues in vegetables like cowpeas. Microbial metabolism is key for pesticide elimination, but bacteria efficient in cyromazine degradation are limited, with uncharacterized enzymes. This study isolated a highly efficient cyromazine-degrading bacterium, Mycobacterium sp. M15, from a cowpea field. M15 utilized cyromazine as the sole carbon source for its growth and completely degraded 0.5 mM cyromazine within 24 h. The degradation pathway involved hydrolyzing cyromazine to N-cyclopropylammeline and further to N-cyclopropylammelide, with amino groups removed sequentially. The cyclopropylamine group in N-cyclopropionamide continued to hydrolyze to cyanuric acid. A protein, CriA, identified as an aminohydrolase in M15, degraded cyromazine to N-cyclopropylammeline. Using CriA reduced cyromazine residues on cowpea surfaces and completely degraded them in immersion solutions. These findings offer insights into cyromazine's microbial degradation mechanism and highlight the potential of cyromazine-degrading enzymes in enhancing food safety.

Photocatalytic degradation of methamidophos in water using zinc oxide as a photocatalyst

Conventional agriculture and the need to satisfy the demand for food, cause different types of pesticides to be used indiscriminately, causing them to be dispersed into ecosystems by wind and water currents, representing a serious environmental problem. For this reason, it is important to apply effective technologies for the elimination of pesticides from water bodies. In the present research, heterogeneous photocatalysis using ZnO as a photocatalyst was applied to evaluate the degradation of methamidophos in contaminated water prepared in ultrapure water and river water. Considering the working parameters of 3 g/L of zinc oxide, a concentration of 50 mg/L of methamidophos, with constant agitation of 300 rpm, temperature 25 ± 2 °C and a natural pH, methamidophos degradation percentages of 86.66 % and 57.96 % were achieved in ultrapure water and river water, respectively. The chloride, sulfates, nitrates, and nitrites anions present in the river water could be responsible for the decrease in the effectiveness of the photocatalytic process. The mathematical models that best describe the degradation process were the pseudo-second order model and the Elovich model.

Magnetic carboxymethyl gond katira-grafted-poly(3-aminobenzoic acid) as an antibacterial biosorbent for purification of acetamiprid-contaminated water

The elimination of pesticides from polluted water is critical due to their harmful environmental and biological impacts. Recently, there has been interest in utilizing natural polymer-based adsorbents as an eco-friendly approach to eliminate or reduce the levels of water pollutants. In this work, we synthesized an antimicrobial and magnetic bionanocomposite consisting of carboxymethyl gond katira-grafted- poly(3-aminobenzoic acid) with iron oxide and zinc oxide NPs (CMT-g-P3ABA/ZnO/Fe3O4) through an in situ polymerization reaction and examined for its ability to adsorb the pesticide acetamiprid (AP). The bionanocomposite was characterized using several analytical techniques, including spectroscopy; XRD presented the crystalline structure of ZnO/Fe3O4 in the CMT-g-P3ABA amorphous matrix. The ZnO/Fe3O4 partially aggregated formation and exhibited polyhedral crystal shapes was depicted by electron microscopy images, vibrating sample magnetometer (45.06 emu/g), porosimetry (5.52 m2/g), and thermal (Chair yield of approximately 43.83 %) and elemental analyses. Under various conditions, including solution pH (4–9), adsorbent dosage (0.005–0.025 g), time of contact (10–30 min), and pesticide preliminary concentration (200–400 mg/L) in 10 mL of the solution. Based on this research, Adsorption data were perfectly fitted by the Freundlich isotherm model with RAP2= 0.99038, while the pseudo-second-order (PSO) model well-explained adsorption kinetics with RAP2= 0.99847. AP adsorption to the CMT-g-P3ABA/ZnO/Fe3O4 bionanocomposite was successful due to hydrophobic interactions, hydrogen bonding, and π-π stacking. Furthermore, adsorption-desorption experiments demonstrated that the bionanocomposite could be regenerated after three reuse cycles without considerable loss of pesticide removal performance. The bionanocomposite also exhibited promising antimicrobial activity in contradiction to test bacteria.

Innovative Frontiers: Advancing Technologies for Pesticide Elimination in Grape Seeds

Grape seeds, a valuable by-product of winemaking, are rich in bioactive compounds with significant economic potential. However, pesticide residues in grape seeds pose risks to human health and product quality. This study explores innovative technologies including cold plasma, ultrasound, aqueous ozone, and gaseous ozone to eliminate pesticide residues from grape seeds. Cold plasma treatment emerged as highly effective, completely eliminating certain pesticides like Triadimenol and Azoxystrobin. Ultrasound treatment also showed promising results, particularly in reducing Pyrimethanil residues. Aqueous ozone treatment achieved moderate reductions, while gaseous ozone exhibited the least efficacy. Factors influencing efficacy included pesticide type, treatment duration, and matrix characteristics. Future research should focus on optimizing parameters to enhance pesticide removal while minimizing impacts on product quality. These findings underscore the importance of tailored approaches for pesticide elimination, contributing to safer agricultural practices and consumer health

Biological treatment of pesticide-containing wastewater from coffee crops: selection and optimization of a biomixture and biobed design.

The biopurification systems (BPS) or biobeds are employed for the treatment of pesticide-containing wastewater of agricultural origin. The use of these devices for pesticide removal requires the proper optimization of the composition of biomixtures (BPS active matrix) according to the target pesticides applied on a specific crop and the available materials used in their elaboration. This work aims to design a biomixture for the simultaneous treatment of several pesticides applied in coffee crops, according to local practices in Costa Rica. Three biomixtures containing either coffee husk, coconut fiber or rice husk (as the lignocellulosic substrate) were applied for the removal of 12 pesticides. The profiles of pesticide elimination and the mineralization of radiolabeled chlorpyrifos (14C-chlorpyrifos) revealed that the best performance was achieved with the coconut fiber biomixture, even though similar detoxification patterns were determined in every biomixture (according to immobilization in Daphnia magna and germination tests in Lactuca sativa). The optimization of this biomixture's composition by means of a central composite design permitted the definition of two optimal compositions (compost:soil:coconut fiber, % v/v) that maximized pesticide removal: i. 29:7.3:63.7 and ii. 11:7.3:81.7. The validation of these optimized compositions also included the use of an alternative soil from another coffee farm and resulted in overall DT50 values of 7.8-9.0 d for the pesticide mixture. Considering the removal kinetics in the optimized biomixture, a 1 m3 BPS prototype was dimensioned to be eventually used in local coffee farms. This work provides relevant information for the design and implementation of BPS at on-farm conditions for the treatment of pesticide-containing wastewater of a major crop.

Modern Applications of Porphyrin-Based MOFs in Agriculture

Nanosized metal-porphyrinic frameworks are an interesting class of porous electro- and photoactive materials finding applications in medicine (photodymanic therapy, photothermal therapy, drug delivery and chemotherapy, immunotherapy), [1], sanitary and antimicrobial devices [2], waste water purification [3], photocatalytic organic transformations [4], production of solar fuels [5], and more recently, in agriculture [6]. The fact that porphyrin derivatives are colored, they are prone for the photosensitization of singlet oxygen (1O2(g); a reactive oxygen species of type II) either at the solid state/air interfaces or in solution leading to applications listed above using visible light. In fact, they even do this efficiently. Reactive oxygen species of type I (for examples, H-O radical, HO-OH, superoxide radical, perhydroxyl radical, etc) are also photo-produced when given metals inside the porphyrins and metallic nodes in the frameworks are used, or when the metal-porphyrinic frameworks form a composite with another semiconductor. Moreover, the size of the nanoparticles can be tailored. All of these properties are cleverly exploited in the field of agriculture and include the following applications: controlled delivery of pesticides and agro-chemicals, detection of pesticides and pathogenic metals, elimination of pesticides and toxic metals, and photodynamic antimicrobial activity, and the nanosized metal-porphyrinic frameworks also have an important implication in food safety. This presentation will describe these features along with new experimental results.

Fate and removal of pesticides in solid and liquid phases of metropolitan, urban and rural-scale wastewater treatment plants

In this study, the change of occurrence, distribution, seasonal variation and removal of pesticides, atrazine (ATZ), chlorpyriphos (CPR) and chlorfenvinphos (CFV), were investigated both in liquid and solid phases of three different types of wastewater treatment plants (WWTPs). Treatment configurations of the studied WWTPs consist of a metropolitan advanced biological treatment system (4-stage Bardenpho), urban-scale waste stabilization pond (WSP) and rural-scale horizontal subsurface flow constructed wetland (HSSCW).ATZ removal efficiencies (59.8 %–92.4 %) were higher than CPR and CFV removal efficiencies at all WWTPs. CPR and CFV are removed at 78.5 % and 53.1 % efficiency, respectively, from the influent of advanced biological treatment system. CPR and CFV removals were 21.6 and 22.7 % at WSP, respectively.One of the important findings is that ATZ and CFV were removed at higher percentages in primary treatment than in biological treatment in advanced biological WWTP. Sorption onto sludge has been evaluated as an effective removal mechanism for pesticide elimination, at least as much as biodegradation/biotransformation. All investigated pesticides were detected in higher concentrations in primary sludge (168.8–399.5 μg/kg) compared to secondary sludge (21.9–146.3 μg/kg) in advanced biological WWTP and in facultative sludge (447.8–1044.7 μg/kg) compared to anaerobic sludge (250.0–613.0 μg/kg) in WSP. It was determined that ATZ was the most treated compound in the liquid phase under anaerobic conditions among the studied pesticides. In line with these results, approximately 45 % removal efficiency was determined for CPR and CFV in the anaerobic digestion process present in advanced biological WWTP.

Inclusions of Pesticides by β-Cyclodextrin in Solution and Solid State: Chlorpropham, Monuron, and Propanil.

Persistence and degradation are important factors in determining the safe use of such synthetic products, and numerous studies have been addressed to develop pesticide remediation methods aimed at ameliorating these features. In this frame, the use of different cyclodextrins (CDs) molecules has attracted considerable attention due to their well-known non-toxic nature, limited environmental impact, and capability to reduce the environmental and health risks of pesticides. CDs appear to be a valuable tool for the elimination of pesticides from polluted areas as well as for better pesticide formulations that positively influence their hydrolysis or degradation. The present work investigates the interaction between β-cyclodextrins and three commonly used pesticides (i.e., chlorpropham, monuron, and propanil) both in solution and in the solid state by means of UV-Vis, FT-IR, and X-ray powder diffractometry. We show that such interactions result in all three cases in the formation of inclusion complexes with a 1:1 stoichiometry and binding constants (Kb) of 369.9 M-1 for chlorpropham, 292.3 M-1 for monuron, and 298.3 M-1 for propanil. We also report the energy-minimized structures in silico for each complex. Our data expand and complement the available literature data in indicating CDs as a low-cost and very effective tool capable of modulating the properties that determine the environmental fate of pesticides.

Hybrid clay-based materials for organic dyes and pesticides elimination in water

Hybrid clay-based materials for organic dyes and pesticides elimination in water

Elimination of pesticide from high salinity wastewater by electrochlorination process: Active chlorine species and scale-up performance

Active chlorine species-mediated electrochemical process is a promising strategy for refractory pollutants and ammonia removal in high salinity organic wastewater. Herein, we constructed an electrochlorination (E-Cl) process with the help of the high concentration of chloride ions (Cl−) in the wastewater to realize the efficient treatment of pesticide wastewater. The E-Cl process exhibited excellent chemical oxygen demand (COD, 86.43%) and atrazine (ATZ, 98.67%) removal efficiency for the actual pesticide wastewater since active chlorine species, including free chlorine and reactive chlorine species (RCS), and hydroxyl radical (•OH) were all in-situ produced during the electrolysis process. The quenching experiments indicated that the free chlorine was the primary oxidizing substance for the decomposition of ATZ, and the RCS and •OH mainly enhanced the mineralization of intermediate products. In addition, the inhibition mechanism of different background substances in the E-Cl process was different. The toxicity test and three-dimensional fluorescence spectrum all proved that the E-Cl process could effectively remove ATZ and other organic matter from the actual pesticide wastewater. Finally, an E-Cl pilot reactor was designed and the pilot-scale experiments showed that the COD and NH4+-N of the actual pesticide wastewater after the treatment of the E-Cl process were < 50 mg/L and < 1.5 mg/L, and the energy consumption (EC) was ∼4.98 kWh/m3. The successful treatment of actual pesticide wastewater by the E-Cl process suggests that this is a promising method for treating organic pollutants and ammonia under highly salinity conditions.

Green biosynthesized N-doped Bi2O3@SnO2 nanocomposite for efficient remediation of endocrine disrupting pesticides

Many persistent and low-cost pesticides are regularly used for domestic, agricultural, and industrial purpose. Bioaccumulation and toxicity of pesticides have raised environmental concerns, highlighting the need for effective removal techniques by using nanomaterials. The ability of hybrid nitrogen incorporated bismuth oxide with stannous oxide (N-Bi2O3@SnO2) were utilized for the removal of Ethion (ET) and Toxaphene (TP) pesticides. Leaves of A. indica (commonly found plant in India) employed as a natural surfactant and deionised water as a greener solvent. The purity and crystallinity of the deformed spherical nanoparticle (10–80 nm) were ensured by the sharp peaks acquired by PXRD. Subsequently, N-Bi2O3@SnO2 nanocomposite was investigated for the elimination of pesticides at discrete reaction parameters (pollutant: 2–10 mgL−1; catalyst: 15–35 mg; pH: 3–11, dark-sunlight). N-Bi2O3@SnO2 nanocomposite showed maximum degradation (ET:96 % and TP:90 %) with 30 mg catalytic dosage, at initial concentration of pesticide (2 mgL−1) at neutral pH under sunlight irradiation. Larger surface area (75 m2g−1), more negative value of zeta potential (–23.4 mV), and lower bandgap (2.1 eV) supported the effective photocatalytic efficiency of N-Bi2O3@SnO2 nanocomposite. The presence of holes, O2, and OH radicals were responsible for the breakdown of the complex structure of ET and TP, confirmed by scavenger analysis. Safer metabolites formed after degradation confirmed by GC–MS analysis. Conclusively, by virtues greater efficiency of reusability (n = 8), stability, and greater charge separation, hybrid N-Bi2O3@SnO2 nanocomposite may prove as an alternative catalyst for industrial application with intense scope.

Pesticide residue elimination for fruits and vegetables: the mechanisms, applications, and future trends of thermal and non-thermal technologies

• Thermal and non-thermal technologies would eliminate pesticide residues. • Non-thermal technologies are superior to thermal technologies in pesticide residues decrease and quality attributes of fruits and vegetables retain. • Combined technologies are more effective than individual technologies. • Elimination efficiency is dependent on product types, pesticide characteristics, and operation parameters. • Green and pollution-free technologies and combined processing technologies are trends. Pesticide residues on food are threatening human health and wellbeing, ecological security. Food processing is one of the necessary ways to eliminate residues to guarantee the safety and sustainable development of the environment. This review outlines the mechanisms, applications, and factors influencing the efficiency as well as their limitations of pesticide residue elimination technologies. Conventional thermal processing technologies like drying, blanching, baking, and roasting have been proved to reduce pesticides extensively whereas sometimes concentration effects occur, and more toxic metabolites or by-products are generated. Additionally, the negative effects on quality attributes of fruits and vegetables (F&V) should be considered. Several innovative non-thermal processing technologies like ultrasound, cold plasma, high-pressure processing, and pulsed electric fields have flourished currently, which show great ability to eliminate pesticide residues significantly with minimal impact on the quality of F&V. In particular, heat-sensitive nutrients like ascorbic acid, phenolics, and carotenoids would retain to a great extent. Similarly, these technologies have their limitations. Furthermore, there is much information about combined processing technology affecting the pesticide behaviors of F&V. Finally, the future developments for pesticide elimination of these technologies are identified and discussed.

ZnO hollow pitchfork: coupled photo-piezocatalytic mechanism for antibiotic and pesticide elimination

A hollow ZnO pitchfork was synthesized via a hydrothermal technique for the pollutant degradation.

Photocatalytic degradation-based efficient elimination of pesticides using ruthenium/gold metal nanoparticle-anchored zirconium dioxide

Ruthenium and gold metal nanoparticles-incorporated zirconium dioxide (ZrO2@Ru and ZrO2@Au) nanostructures were developed as promising photocatalysts for wastewater remediation.

Native natural enemies in Mediterranean melon fields can provide levels of pest control similar to conventional pest management with broad-spectrum pesticides

Pest control in Mediterranean open-field melon crops currently relies on repeated pesticide applications. A lack of IPM programs that take into account naturally occurring biological control agents in the crop could be due, in part, to a lack of knowledge of the natural enemies associated with melon and their pest control potential. We estimated the abundance of pests and natural enemies in fields managed with a conventional insecticide regime (CPR) and a ‘no insecticide’ regime (NPR), with all fields receiving fungicide applications (sulphur or triadimenol), as required. In a two-year study, six melon fields were sampled periodically during spring and early summer by visual observations of leaves and the extraction of arthropods from flowers using Berlese funnels. The most abundant phytophagous arthropods on melon leaves were thrips (38.9% of total counts), aphids (31.5%), spider mites (26.8%) and whiteflies (2.8%). Aphis gossypii was significantly more abundant in CPR than in NPR fields, whereas whiteflies and thrips had similar abundance in the two treatments. Spider mites were more abundant in NPR than in CPR fields. The main groups of natural enemies on leaves were Orius spp. (76.1% of total counts), phytoseiids (7.4%), predatory thrips (7.1%) and cecidomyiids (5.6%), and all were significantly more abundant in NPR than in CPR fields. The primary predators in flowers were Orius spp. (67.4%) and Aeolothrips spp. (32.6%), and both were significantly more abundant in NPR than in CPR fields. Orius spp. was inferred to be the primary biological control agent of aphids, as few aphids were mummified by parasitoids. The control of aphids by Orius spp. was probably mediated by apparent competition with thrips, which are a preferred prey of Orius spp. In summary, elimination of pesticides from the management regime enhanced the abundance of natural enemies in the melon crop, and natural biological control limited pest infestations in NPR fields as well as did broad-spectrum insecticides in CPR fields. Therefore, IPM strategies for melon production should consider conservation of natural biological control agents as an effective alternative to conventional regimes that rely primarily upon insecticides.

Plasma Degradation of Pesticides on the Surface of Corn and Evaluation of Its Quality Changes

Plasma is a surface decontamination tool that is widely used in the food fields for pesticide degradation. In this study the effect of plasma on pesticide elimination from the surface of corn and the corn quality changes were tested as functions of power, air flow rate, treatment time, and frequency. Results indicated that plasma treatment for 60 s at 1000 mL·min−1 air flow rate, power of 20 W, and frequency of 1200 Hz, achieved the largest degradation efficiency up to 86.2% for chlorpyrifos and 66.6% for carbaryl, both of which were below the maximum residues limit of grains. Most importantly, after plasma treatment, there was a remarkable decrease (p &lt; 0.05) in moisture content and starch content for treated corn compared with control. The acid value for treated corn showed a prominent increase (p &lt; 0.05), but within the acceptable range of the standard. The vitamin B2 content of treated corn did not show a significant difference (p &gt; 0.05). All results of this study demonstrated that plasma treatment is a promising technology with the ability to remove pesticide residues on corn while maintaining its quality within acceptable limits.

Transformation pathways and toxicity assessments of two triazole pesticides elimination by gamma irradiation in aqueous solution

The presence of triazoles in the environment has received increasing attention due to their potential adverse effects on human and ecosystem health. Nevertheless, triazoles are weakly sunlight and cannot be effectively removed by solar radiation. Advanced oxidation processes (AOPs), including gamma irradiation, present an alternative technology for removing these pesticides from contaminated water. In this study, the degradation of two triazole pesticides (Myclobutanil and Penconazole) in aqueous solution was studied by gamma irradiation. Different factors such as irradiation dose, pH, radical scavenger and natural organic matter were examined for their effects on the removal of these triazoles. A kinetic study was performed and the by-products were identified by HPLC-QTOF-MS/MS. The results showed that the degradation process of the target molecules was of pseudo-first order and the elimination reached at least 90% at an absorbed dose of 575 Gy and 460 Gy for Myclobutanil and Penconazole, respectively. The percentage of elimination increased with dose and the degradation process was accelerated under neutral conditions. Humic acid showed a negative influence on the degradation efficiency, which decreased from 100% to 40.67% for Myclobutanil and to 50% for Penconazole at a dose of 1.2 kGy when the humic acid concentration was 20 mg.L−1. Five degradation products were identified for Myclobutanil and ten for Penconazole and most of the degradation by-products were formed by hydroxylation. To check the impact of these by-products, a toxicity study was conducted on Wistar rats and no increase in toxicity was observed. The mineralization of both pesticides by gamma irradiation was studied using 1HNMR analysis and results confirm that both molecules were completely mineralized at 1.2 kGy. According to the overall analysis, the radiolysis process seems to be an alternative to remove triazoles from contaminated waters.

The pace-of life explains whether gills improve or exacerbate pesticide sensitivity in a damselfly larva

Trait-based approaches are promising to make generalizations about the sensitivity of species and populations to pesticides. Two traits that may shape the sensitivity to pesticides are the surface area (related to pesticide uptake) and the metabolic rate (related to pesticide elimination). We compared the sensitivity of damselfly larvae to the pesticide chlorpyrifos and how this was modified by loss of external gills (autotomy, reducing the surface area) in both fast pace-of-life (high metabolic rate) and slow pace-of-life (low metabolic rate) populations of Ischnura elegans. The slow-paced populations were more sensitive to the pesticide than the fast-paced populations in terms of survival, growth and energy metabolism. This suggests the higher metabolic rate of fast-paced populations enabled a faster pesticide elimination. Pesticide exposure also reduced heat tolerance, especially in slow-paced larvae under hypoxia. Gill loss had opposite effects on pesticide sensitivity in slow- and fast-paced populations. In slow-paced larvae, gill loss lowered the sensitivity to the pesticide, while in fast-paced larvae, gill loss increased the sensitivity. This difference likely reflects the balance between the roles of the gills in pesticide uptake (more detrimental in slow-paced populations) and oxygen uptake (more important in fast-paced populations). Our results highlight the need to consider trait interactions when applying trait-based approaches to predict the sensitivity to pesticides.

Optimization of a rice cooking method using response surface methodology with desirability function approach to minimize pesticide concentration

Rice is contaminated with pesticides applied in pre and post-harvest. These contaminations could be reduced through household operations like washing and cooking. Therefore, in the present research, a pre-soaking rice cooking method was used to reduce pesticides residues. Response Surface Methodology with Central Composite Design was applied to minimize pesticides concentration by choosing the best soaking time and water:rice grain relation before cooking. A quadratic polynomial equation was obtained. Desirability function approach gave the optimal cooking conditions as 14 h soaking time and water:rice grain relation of 3. This process allowed a pesticide elimination of 100.0%, 93.5%, 98.4%, 98.5%, 99.0%, and 95.0%, of azoxystrobin, cyproconazole, deltamethrin, epoxiconazole, kresoxim-methyl and penconazole, respectively.

The Improving Conditions for the Aerobic Bacteria Performing the Degradation of Obsolete Pesticides in Polluted Soils

Currently, in the territory of Kyrgyzstan, 50 storage facilities of obsolete pesticides exist; they store about 5000 tons of these hazardous chemicals. The storage conditions have become unusable for a long time. They pose a serious threat to the people living there, livestock, and the environment. The main purpose of this research was the use of selected bacteria with cytochrome P450 genes for the bioremediation of polluted soils around the burial sites in model soil experiments. In the first trial of biodegradation experiments, one contaminated soil was used without any changes in chemical contents, and in the second, the physical and chemical contents of the soil were improved to maintain the bioremediation conditions. The soils in both variants were treated 3 times (ie, once a month) with suspensions of a single culture or a blend of active bacteria (1 × 108 cells/mL) selected from in vitro biodegradation experiments. Two control units without the addition of the bacteria culture were also run. The quantification of targeted persistent organic pollutants (POPs) before and after biodegradation was performed by capillary gas chromatography (GC) coupled to a mass spectrometer. In 6 months, obsolete pesticides such as dieldrin, α-endosulfan, β-endosulfan, and 4-heptachlor-epox pure were able to degrade almost completely, up to 98% to 99.0%, by the blend of bacteria and the single culture of bacteria. Endrin aldehyde showed more resistance as the blend of bacteria was able to degrade it to 59.77%. To improve the aerobic degradation for elimination of pesticides from contaminated soils, it is necessary to create optimal agrotechnical and agrochemical conditions.