Commercial Pesticide Formulations Research Articles

A novel pesticide has lethal consequences for an important pollinator

Wild bees pollinate crops and wildflowers where they are frequently exposed to pesticides. Neonicotinoids are the most commonly used insecticide globally, but restrictions on their use and rising pest resistance have increased the demand for alternative pesticides. Flupyradifurone is a novel insecticide that has been licenced globally for use on bee-visited crops. Here, in a semi-field experiment, we exposed solitary bees (Osmia lignaria) to a commercial pesticide formulation (Sivanto Prime) containing flupyradifurone at label-recommended rates. We originally designed the experiment to examine sublethal effects, but contrary to our expectations, 100 % of bees released into pesticide-treated cages died within 3 days of exposure, compared to 0 % in control plots. Bees exposed to flupyradifurone a few days after the initial application survived but endured prolonged sublethal effects, including lower nesting success, impairment to foraging efficiency, and higher mortality. These results demonstrate that exposure to this novel insecticide poses significant threats to solitary bees and add to a growing body of evidence indicating that this pesticide can have negative impacts on wild bees at field-realistic concentrations. In the short-term, we recommend that commercial formulations containing flupyradifurone should be restricted to non-flowering crops while a reassessment of its safety can be conducted. In the long-term, environmental risk assessors should continue to develop risk assessments that are truly holistic and incorporate the ecological and life history traits of multiple pollinator species.

Novel insights into the photochemical transformation of neonicotinoid insecticides: Potential involvement of adjuvants

Commercial pesticide formulations often contain both the active ingredient and different adjuvants, the potential impacts of adjuvants on pesticides’ transformation have been barely considered. In this study, effects of typical adjuvants (i.e. hexadecyl trimethyl ammonium bromide (CTAB), hexadecyl trimethyl ammonium chloride (CTAC) and p-Octyl polyethylene glycol phenyl ether (TX-100)) on the photodegradation of four selected neonicotinoid insecticides (NIs), including thiamethoxam (TMX), dinotefuran (DIN), imidacloprid (IMP) and acetamiprid (ACP) were systematically investigated. Specifically, CTAB and CTAC exhibited minimal or no impact on the photolysis of four NIs, while TX-100 significantly inhibited their decay. Such inhibitory effect could mainly be attributed weakening the formation of key transient intermediates, such as the corresponding radical cation (NI•+), radical anion (NI•-) as well as hydrated electron (eaq-). Photoproducts identification revealed a novel transformation pathway of NIs in the presence of TX-100, characterized by de-chain reactions, resulting in the formation of photostable dimeric photoproducts. These dimers exhibited varying toxicity: for TMX, DIN and IMP, their corresponding dimers showed increased toxicity compared to their parent compounds, whereas for ACP, they displayed decreased toxicity. These provide important information for the evaluation the environmental fates and toxicology of formulaic NIs.

Chronic effects of commercial pesticide preparations on biomarkers and reproductive success in earthworm Eisenia andrei

Chemical pollution resulting from pesticide usage has been a continuous issue since the 1960s, despite comprehensive European Union legislation designed to safeguard human health and the environment from the adverse effects of pesticides. While regulatory risk assessments primarily focus on the active ingredients, recent research indicates ecotoxicological impacts of commercial preparations on non-target organisms, particularly within the soil ecosystem where key species such as earthworms play a vital role in maintaining soil quality and fertility. Therefore, the aim of this study was the assessment of the long-term effects of the following respective commercial preparations: the insecticides Sumialfa (esfenvalerate) and Calypso (thiacloprid), as well as the herbicides Frontier (dimethenamid-p) and Filon (prosulfocarb) on the earthworm Eisenia andrei in standardized soil during long-term exposures of 7, 14, and 28 days. To study the possible effects on different levels of biological organization, enzymatic biomarkers: acetylcholinesterase (AChE), carboxylesterase (CES) glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx); non-enzymatic biomarkers: multixenobiotic resistance activity (MXR), levels of glutathione (GSH), and reactive oxygen species (ROS) as well as reproductive success were investigated. While Calypso appeared to be the least toxic substance, all pesticides showed significant effect on multiobiomarker response in E. fetida. That being said, the response of MXR activity was significantly altered by all tested pesticides indicating MXR being the most sensitive endpoint of the present research. Recovery of MXR was observed after 28 days, however, only in case of exposure to Filon, while the recovery of CAT activity was recorded after 28 days as well, subsequent to Sumialfa exposure. Reproductive success was negatively impacted regarding the Frontier and Sumialfa exposure at the highest concentration (100 mg/kg) reflected in reduced number of cocoons, while only the exposure to Frontier (100 mg/kg) reduced the number of juveniles. Based on the results, it is important to include commercial pesticide formulations in pesticide risk assessments. The toxicity classifications of the studied pesticides suggest the potential detrimental consequences to the key soil species in terrestrial ecosystems at various concentrations. Future studies should include other soil species as well as investigation of higher levels of biological organization, i.e., behavioral endpoints, to determine the potential risks to terrestrial ecosystems.

Stable isotope composition of pesticides in commercial formulations: The ISOTOPEST database

By assessing the changes in stable isotope compositions within individual pesticide molecules, Compound Specific Isotope Analysis (CSIA) holds the potential to identify and differentiate sources and quantify pesticide degradation in the environment. However, the environmental application of pesticide CSIA is limited by the general lack of knowledge regarding the initial isotopic composition of active substances in commercially available formulations used by farmers. To address this limitation, we established a database aimed at cataloguing and disseminating isotopic signatures in commercial formulations to expand the use of pesticide CSIA. Our study involved the collection of 25 analytical standards and 120 commercial pesticide formulations from 23 manufacturers. Subsequently, 59 commercial formulations and 25 standards were extracted, and each of their active substance was analyzed for both δ13C (n = 84) and δ15N CSIA (n = 43). The extraction of pesticides did not cause significant isotope fractionation (Δ13C and Δ15N < 1‰). Incorporating existing literature data, stable carbon and nitrogen isotope signatures varied in a relatively narrow range among pesticide formulations for different pesticides (Δ13C and Δ15N < 10‰) and within different formulations for a single substance (Δ13C and Δ15N < 2‰). Overall, this suggests that pesticide CSIA is more suited for identifying pesticide transformation processes rather than differentiating pesticide sources. Moreover, an inter-laboratory comparison showed similar δ13C (Δ13C ≤ 1.2 ‰) for the targeted substances albeit varying GC-IRMS instruments. Insignificant carbon isotopic fractionation (Δ13C < 0.5‰) was observed after 4 years of storing the same pesticide formulations, confirming their viability for long-term storage at 4 °C and future inter-laboratory comparison exercises. Altogether, the ISOTOPEST database, in open access for public use and additional contributions, marks a significant advancement in establishing an environmentally relevant pesticide CSIA approach.

Immuno-endocrine alterations and oxidative stress induced by commercial formulations of pesticides in the tegu lizard (Salvator merianae)

Recent research has shown the risk of environmental contamination by pesticides in Argentina. Salvator merianae is considered as “sentinel species” for monitoring their effects. We intended to investigate growth, immunological and endocrine functions, and oxidative stress in S. merianae exposed to two commercial brands of the herbicide glyphosate: Roundup and Panzer Gold, as well as, to two insecticides: chlorpyrifos, and cypermethrin. Our results showed a higher increase in growth in animals exposed to Roundup and chlorpyrifos and a lower increase in those exposed to Panzer Gold. Higher total leukocyte and lymphocyte count values were observed in lizards exposed to Panzer Gold. The heterophils/lymphocytes ratio decreased in all treated animals. Regarding lobularity index, natural antibodies titers, and complement system activity values, lizards exposed to cypermethrin had higher values. Low corticosterone levels were observed in animals exposed to Roundup. Our results reveal different toxic effects of pesticides contributing to the knowledge of the pesticides’ potential deleterious impact in the habitat of S. merianae.

Evaluation of the cytotoxicity and genotoxicity of glufosinate-ammonium at technical and commercial grades in HepG2 cells

Exposure to genotoxic agents is associated with the development of cancer and related diseases. For this reason, assessing the genotoxicity of chemical compounds is necessary. In this line, information about the genotoxic effect of glufosinate-ammonium (GLA) has been reported only for the technical grade. However, humans are frequently exposed to commercial formulations of pesticides. Commercial formulations are characterized by using inner agents that increase toxicity compared to pesticides in technical grade. This study aimed to determine the cytotoxic and genotoxic effects of GLA on HepG2 cells. MTT and comet assays were performed to evaluate cell viability and DNA damage, respectively. HepG2 cells were exposed for 24 h to different concentrations of GLA (at 0.01 µg/mL; 0.04 µg/mL; 0.1 µg/mL; 0.24 µg/mL; 0.52 µg/mL; 1.25 µg/mL; 2.62 µg/mL and 13.12 µg/mL) in commercial- (Finale Ultra®) or technical-grade (GLAT). The results indicated that only Finale Ultra® induced a reduction in cell viability at 13.12 µg/mL. Furthermore, exposure to Finale Ultra® or GLAT was associated with increased DNA damage at concentrations from 0.52–13.12- µg/mL. This study shows the genotoxic effect of GLA on HepG2 cells.

The Effect of Washing, Blanching and Frozen Storage on Pesticide Residue in Spinach.

Spinach (Spinacia oleracea L.) is a representative green leafy vegetable commonly consumed fresh or as a ready-to-cook frozen product, with increasing consumption because of its many health-related properties. Among leafy vegetables, spinach poses a major concern in terms of pesticide residue detection due to common phytotechnical practices. In this study, spinach leaves were treated in the open field with three commercial pesticide formulations containing propamocarb, lambda-cyhalothrin, fluopicolide and chlorantraniliprole at the highest concentration. The effects of the successive processing steps of washing, blanching, freezing and frozen storage were evaluated on the levels of the four pesticide residues and the degradation product (propamocarb n-desmethyl). The washing step caused a reduction of fluopicolide and chlorantraniliprole of -47% and -43%, respectively, while having a mild effect on lambda-cyhalothrin content (+5%). A two-minute blanching step allowed for the reduction of pesticides content ranging from -41% to -4% with respect to the washed sample. Different behaviors were depicted for longer blanching times, mainly for propamocarb, reaching -56% after 10 min of treatment. Processing factors higher than 1 were reported mainly for lambda-cyhalothrin and fluopicolide. Frozen storage led to a slight increase in the pesticide content in samples treated for 6 and 10 min. The optimal blanching treatment for spinach, submitted to freezing and frozen storage, seems to be 2 min at 80 °C.

Impaired physiological responses and neurotoxicity induced by a chlorpyrifos-based formulation in Caenorhabditis elegans are not solely dependent on the active ingredient

The current massive and indiscriminate agrochemicals usage, which is inexorably linked to the toxic consequences to the environment and people, represents a great concern. Our work aimed to compare the toxicity induced by chlorpyrifos in its pure form (CPF) with that of a commercial formulation containing allegedly inert ingredients (CBCF) using Caenorhabditis elegans as in vivo model. After a 48 h exposure period, CBCF was 14 times more lethal than CPF; Hatching, brood size, body length and motor-related behavioral parameters were decreased, but these effects were significantly higher in CBCF-exposed worms. Additionally, CBCF induced significant morphological changes in cholinergic neurons, which are associated with the motor-related behavioral parameters. Finally, by analyzing the CBCF, we detected the presence of potentially-toxic metals that were not specified in the label. The presented results highlight the toxicological relevance of components present in the commercial formulations of pesticides, which have been claimed as inert compounds.

Enzyme Inhibition-Based Assay to Estimate the Contribution of Formulants to the Effect of Commercial Pesticide Formulations.

Pesticides can affect the health of individual organisms and the function of the entire ecosystem. Therefore, thorough assessment of the risks associated with the use of pesticides is a high-priority task. An enzyme inhibition-based assay is used in this study as a convenient and quick tool to study the effects of pesticides at the molecular level. The contribution of formulants to toxicological properties of the pesticide formulations has been studied by analyzing effects of 7 active ingredients of pesticides (AIas) and 10 commercial formulations based on them (AIfs) on the function of a wide range of enzyme assay systems differing in complexity (single-, coupled, and three-enzyme assay systems). Results have been compared with the effects of AIas and AIfs on bioluminescence of the luminous bacterium Photobacterium phosphoreum. Mostly, AIfs produce a considerably stronger inhibitory effect on the activity of enzyme assay systems and bioluminescence of the luminous bacterium than AIas, which confirms the contribution of formulants to toxicological properties of the pesticide formulation. Results of the current study demonstrate that "inert" ingredients are not ecotoxicologically safe and can considerably augment the inhibitory effect of pesticide formulations; therefore, their use should be controlled more strictly. Circular dichroism and fluorescence spectra of the enzymes used for assays do not show any changes in the protein structure in the presence of commercial pesticide formulations during the assay procedure. This finding suggests that pesticides produce the inhibitory effect on enzymes through other mechanisms.

Subcellular Responses and Avoidance Behavior in Earthworm Eisenia andrei Exposed to Pesticides in the Artificial Soil

Earthworms are key organisms of the soil ecosystem and bioindicators for soil quality. While pesticides are used for the improvement of crop yields, they also present a burden for soil organisms. To understand the complex effects of pesticides on soil organisms, it is important to test these effects in soil exposures to include influences of the soil matrix on the toxicity. Therefore, the aim of this study was the assessment of the effects pesticides on earthworm Eisenia andrei. In an initial screening, active ingredients and commercial preparations were tested for comparison. Since the commercial preparations showed a higher toxicity, all further investigations (biomarkers, multixenobiotic resistance (MXR) activity, and avoidance behavior) were performed using the commercial pesticide formulations only: Sumialfa (esfenvalerate), Calypso (thiacloprid), Frontier (dimethenamid-p), and Filon (prosulfocarb). Significant differences in avoidance behavior were observed for Filon and Frontier. All pesticides inhibited the MXR activity and affected oxidative stress-related markers. Frontier was the only pesticide that did not affect enzymatic biomarkers related to neurotransmission. The results show the potential hazards associated with the usage of the tested pesticides and the importance of evaluating the effects of commercial pesticide preparations for a more realistic insight into the adverse effects on the environment.

Homogeneous Photo-Fenton Degradation and Mineralization of Model and Simulated Pesticide Wastewaters in Lab- and Pilot-Scale Reactors

The homogeneous photocatalytic degradation of model pesticide clopyralid (CLPR) has been investigated under various experimental setups. Lab-scale experiments under UV-A radiation in an acidic environment showed that the degradation rate generally increased when increasing either Fe3+ or H2O2 concentration up to a point beyond which (i.e., 100 mg L−1 for peroxide or 7 mg L−1 for ferric ions) Fenton reagents had little or even detrimental effect on degradation. Thus, there is an optimum concentration of Fenton reagents for maximizing treatment performance, beyond which degradation rates are not enhanced. Excessive concentrations of peroxide and/or catalyst may (i) introduce unnecessary treatment costs, (ii) reduce performance due to scavenging effects, and (iii) raise environmental concerns associated with the disposal of, e.g., high concentrations of iron in the receiving water courses. Switching from UV-A to visible light led to similar rates of degradation, i.e., 86% and 82.2%, respectively, after 90 min of reaction, highlighting the potential of using renewable energy, i.e., natural sunlight, to drive the process. Treatment for 120 min also led to 90% mineralization and quantitative release of nitrogen originally present in the pesticide; this was also accompanied by complete elimination of eco-toxicity to Vibrio fischeri. Pilot-scale experiments were performed in a fountain-type reactor using a commercial pesticide formulation containing CLPR. Both the degradation and mineralization rates increased with increasing the intensity of the incident UV-A radiation from 1.88 to 4.03 mW cm−2. Experiments were also conducted with different liquid volumes, i.e., from 3 to 8 L. Illumination of 5 L wastewater resulted in 80% mineralization after 60 min and this only slightly decreased to 73% at 8 L. Overall, the findings underline the promising perspectives of the application of the treatment method in upgrading the quality of water and liquid waste containing pesticides.

Cytotoxicity Mechanisms of Eight Major Herbicide Active Ingredients in Comparison to Their Commercial Formulations.

Commercial pesticide formulations contain co-formulants, which are generally considered as having no toxic effects in mammals. This study aims to compare the toxicity of 8 major herbicide active ingredients-namely glyphosate, dicamba, 2,4-D, fluroxypyr, quizalofop-p-ethyl, pendimethalin, propyzamide and metazachlor-with a typical commercial formulation of each active ingredient. Cytotoxicity and oxidative stress capability was assessed in human hepatoma HepG2 cells. Using an MTT assay, formulations of glyphosate (Roundup Probio), fluroxypyr (Hurler), quizalofop-p-ethyl (Targa Super) and dicamba (Hunter) were more toxic than the active ingredient alone. Metazachlor and its formulation Sultan had similar cytotoxicity profiles. Cytotoxicity profiles were comparable in immortalised human fibroblasts. Toxilight necrosis assays showed the formulation of metazachlor (Sultan50C) resulted in significant membrane disruption compared to the active ingredient. Generation of reactive oxygen species was detected for glyphosate, fluroxypyr, pendimethalin, quizalofop-p-ethyl, the formulation of 2,4-D (Anti-Liserons), and dicamba and its formulation Hunter. Further testing of quizalofop-p-ethyl and its formulation Targa Super in the ToxTracker assay system revealed that both products induced oxidative stress and an unfolded protein response. In conclusion, these results show that most herbicide formulations tested in this study are more toxic than their active ingredients in human tissue culture cell model systems. The results add to a growing body of evidence, which implies that commercial herbicide formulations and not just their active ingredients should be evaluated in regulatory risk assessment of pesticides.

Commercial pesticides for urban applications induced population growth and sub-cellular alterations in Raphidocelis subcapitata (Chlorophyceae) at concerning environmental concentrations.

Information regarding the safety and environmental risks of pesticides intended for urban use remains limited. This study aimed to assess the effects of four common pesticides on the microalga Raphidocelis subcapitata: DIAZINON® 25% C. E., Roundup®, URBACIN® 20C. E., and VAPODEL® 20% C. E., which are commercial formulations of diazinon, glyphosate, dichlorvos, and cypermethrin, respectively. According to 96-h inhibition of population growth bioassays, the four pesticide toxicities exemplified the following order: DIAZINON® (diazinon) > Roundup® (glyphosate) > VAPODEL® (dichlorvos) > URBACIN® (cypermethrin). Increasing pesticide concentrations elicited alterations in the specific growth rates (µmax). The macromolecule contents and photosynthetic pigments increased in groups exposed to the highest concentrations of DIAZINON® 25%, Roundup®, and URBACIN® 20 compared to the control group, despite these treatments inducing lower population growth rates. VAPODEL® 20% induced higher growth rates and lower macromolecule content compared to the control. Since active ingredients were not quantified, certain comparisons may prove limiting, but it is important to assess the effects of the whole mixtures in the form that they enter the environment, especially for urban-intended applications or generic formulations with higher additive contents. Finally, this study demonstrated that commercial pesticide formulations designed for urban applications might pose a threat to freshwater microalgae due to their underestimated toxic potential, but further studies are required.

Non-targeted analysis of co-formulants in antifungal pesticide formulations by gas chromatography-tandem high resolution mass spectrometry

In the present study, six commercial pesticide formulations with antifungal activity were characterized. Thus, two complementary injection methods based on gas chromatography were employed: direct injection (DI) and headspace (HS), both coupled to high resolution mass spectrometry (GC-Q-Orbitrap-MS). The combination of both injection modes allowed the tentatively identification of potential co-formulants. Available analytical standards were acquired for their confirmation, and 21 compounds were successfully confirmed. Finally, the concentration of these co-formulants was calculated, finding the highest value in one of the pesticide formulation, at 218.22 g L−1 for cyclohexanone.Results clearly show that this methodology is suitable for the reliable identification of co-formulants in pesticide formulations, offering high sensitivity, and highlighting that five co-formulants were detected by both injection techniques (DI and HS). Moreover, one of the main advantages of the proposed methods was the great capacity for the elucidation of compounds with similar molecular formula, bearing in mind that up to 8 co-formulants with the same molecular formula C10H14, were well differentiated by retention times between 8.46 (1-methyl-3-propylbenzene) and 10.98 min (1,2,3,4- tetramethylbenzene) in one of the pesticide formulation.Toxicity to human health and the environment has been evidenced for the co-formulants detected, finding compounds with relatively high toxicity, as naphthalene and cyclohexanone.

The Effects of Commercial Pesticide Formulations on the Function of In Vitro and In Vivo Assay Systems: A Comparative Analysis

Pesticides are commonly used in agriculture and are an important factor of food security for humankind. However, the overuse of pesticides can harm non-target organisms, and, thus, it is vital to comprehensively study their effects on the different metabolic pathways of living organisms. In the present study, enzyme-inhibition-based assays have been used to investigate the effects of commercial pesticide formulations on the key enzymes of the organisms, which catalyze a wide variety of metabolic reactions (protein catabolism, lactic acid fermentation, alcohol metabolism, the conduction of nerve impulses, etc.). Assay conditions have been optimized, and the limitations of the methods used in the study, which are related to the choice of the solvent for commercial pesticide formulations and optical effects occurring when commercial pesticide formulations are mixed with solutions of enzymes and substrates of assay systems, have been revealed. The effects of commercial pesticide formulations on simple chemoenzymatic assay systems (single-enzyme reactions) have been compared to their effects on complex multicomponent molecular systems (multi-enzyme reactions) and organisms (luminescent bacterium). The in vitro assay systems have shown higher sensitivity to pesticide exposure than the in vivo assay system. The sensitivity of the in vitro assay systems increases with the elongation of the chain of conjugated chemoenzymatic reactions. The effects exerted by commercial pesticide formulations with the same active ingredient but produced by different manufacturers on assay system functions have been found to differ from each other.

MIMERA: An online tool for the sustainable pesticide use at field scale

As echoed in the European Green Deal and Farm to Fork strategy, the EU agricultural policy has clear objectives of improving the sustainability (environmental, economic and social) of farm productions. The environmental goals are supported by promotion of organic farming and the responsible management of inputs such as fertilisers and pesticides. In this framework, there is a need is to provide farmers with tools to evaluate the best options for reducing environmental impact and measure performances in improving the sustainability of their productions. This paper introduces MIMERA, a GIS easy-to-use tool for the sustainable use of pesticides at farm level. MIMERA was developed in the framework of the Train-Agro project funded by the Lombardia Region (Italy), in the framework of the European Agricultural Fund for Rural Development Programme (EAFRD). The main goal is to help professional pesticide users to identify the best pest management strategies by comparing the environmental risk of authorized commercial formulations of pesticides, identifying parcel most at risk within the farm boundaries and suggesting the most appropriate risk mitigation measures for the prevention of surface water contamination. Finally, MIMERA offers the opportunity to track the risk trend of the selected pest management strategies utilized during years. The proposed methodology and structure of MIMERA are described along with underlying data and algorithms are described. An example of its application by considering different pest management strategies adopted by farmers in an area characterized by the intensive presence of maize crop in Lombardia Region is presented.

A Continuous Flow Injection/Indirect Photometric Method for the Detection of Fosetyl Aluminum in Commercial Pesticide Formulations

AbstractBecause of their Physico‐chemical characteristics and its composition, the development of new specific analytical methodologies to determine some highly polar pesticides are required. The reported methods demand long analysis time, expensive instruments and prior extraction of pesticide for detection. The current work presents a new flow injection analysis method combined with indirect photometric detection for the determination of Fosetyl‐Aluminum (Fosetyl‐Al) in commercial formulations, with rapid and highly accurate determination involving only construction of manifold system combined with photometric detector without need some of the pre‐treatments to the sample before the analysis such as extraction or separation. The proposed method is based on the reaction between the Fosetyl‐Al with the colorimetric reagent (Aluminon dye) in an aqueous medium of sodium nitrite resulting in the formation of a red complex and its absorbance is measured using the photometric detector. The proposed method included optimization of several parameters such as sodium nitrite concentration, flow rate, sample volume, Aluminon dye concentration, mixing coil and light intensity. The linear range of the detector response was in the range of 0.005–1.8 mmol/L for the sample with r (coefficient of determination) 0.9909, R2 (correlation coefficient) 0.9954 at 95 % and 0.0041 mmol/L as a limit of detection. The relative standard deviation was less than 1.5 % for 0.005 mmol/L of the analyte (n=11). The proposed method was validated and applied successfully for the determination of Fosetyl‐Al in commercial formulations and can be used as an alternative method for quality control assessment.

Lethal and Sublethal Toxicity of Pesticides Used in Fruit Growing on the Parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae): Implications for Integrated Fruit Fly Management.

The larval-pupal endoparasitoid Diachasmimorpha longicaudata (Ashmead, 1905) is considered one of the main biological control agents of fruit flies Ceratitis capitata Wiedemann (1824) and Anastrepha fraterculus Wiedemann (1830) in Central and South America. The application of pesticides for disease and insect-pest management in fruit species may have adverse effects on the parasitoid. The objective of this study was to evaluate the lethal and sublethal effects via residual contact of commercial pesticide formulations on D. longicaudata. The active ingredients thiamethoxam, indoxacarb, chlorpyrifos, deltamethrin, spinetoram, spinosad, phosmet, lambda-cyhalothrin, malathion, dimethoate, and methidationa showed high toxicity to adults (100% mortality) after 96 h and were classified as harmful (Class 4). In contrast, the formulations of azadirachtin (Agroneem 850 EC, Azact 2.4 EC, Azamax 12 EC, and Fitoneem 850 EC), chlorantraniliprole, bordeaux mixture, sulfur, lufenuron, lime sulphur, novalurom, and mancozeb were rated as innocuous (<10% mortality). In addition, the formulations azadirachtin did not reduce the parasitism and the emergence rate of the F0 generation, the same pesticides added to chlorantraniliprole, azadirachtin A+B (Agroneem 850 EC), and lufenuron did not cause reduction in parasitism and emergence rate of the F1 generation of D. longicaudata. The use of pyrethroids, organophosphates, spinosyns, oxadiazines, and neonicotinoids should be used with caution in IPM programs. While pesticides chlorantraniliprole, azadirachtin formulations, bordeaux mixture, lufenuron, lime sulphur, and mancozeb do not cause lethal and sublethal effects for D. longicaudata adults. The results of this study provide important information for use in integrated pest management programs for fruit fly management.

Development and characterization of iron (III) phthalocyanine modified carbon nanotube paste electrodes and application for determination of fluometuron herbicide as an electrochemical sensor

This study is the first electroanalytical study conducted for the determination of fluometuron herbicide. For this purpose, a new electrode was prepared by combining iron (III) phthalocyanine − 4.4′,4′′,4′′′-tetrasulfonic acid, oxygen monosodium salt hydrated compound (FePc) and multi-walled carbon nanotube powders (MWCNTP). The FePc/MWCNTP composite (hybrid) material prepared in this way was coated on glassy carbon electrode (GCE) and multi-walled carbon nanotube paste electrode (MWCNTPE) using the drop-dry method. Compared to both the bare GCE and MWCNTPE, the modified FePc/MWCNTPE increased the anodic peak current of fluometuron by approximately six fold. Calibration plots of the fluometuron were constructed using the standard addition method with differential puls stripping voltammetry (DPSV) and square wave stripping voltammetry (SWSV) under the optimum conditions. While the working range was determined as 0.4–15.0 mg/L in pH 6.0 Britton Robinson (BR) buffer solution on FePc/MWCNTP electrode with DPSV, this range was found to be 0.4–7.5 mg/L with SWSV. In addition, the limit of detection (LOD) and the limit of quantification (LOQ) values ​​were 69.8 µg/L and 233.0 µg/L, respectively, by DPSV. On the other hand, these two validation values ​​(LOD and LOQ) were 101 µg/L and 337 µg/L by SWSV, respectively. Subsequently, cyclic voltammetric (CV) studies were carried out to elucidate the electrochemical behavior and electrode mechanism of the fluometuron herbicide. In addition, the interference effects of some cations and pesticides in the determination of fluometuron were examined. Finally, studies of recovery of fluometuron herbicide from tap water and determination of fluometuron in Cottonex 500 SC® commercial pesticide formulation using the proposed DPSV method and modified FePc/MWCNTP electrode were performed with very low relative error.

Neonicotinoid-containing insecticide disruption of growth, locomotion, and fertility in Caenorhabditis elegans.

Neonicotinoids, a class of insecticides structurally similar to nicotine that target biting and sucking insects, are the most widely used insecticides today, in part due to their supposed low toxicity in other organisms. However, a growing body of research has found that even low doses of neonicotinoids can induce unexpected negative effects on the physiology and survival of a wide range of non-target organisms. Importantly, no work has been done on the commercial formulations of pesticides that include imidacloprid as the active ingredient, but that also contain many other components. The present study examines the sublethal effects of “Tree and Shrub”™ (“T+S”), a commercial insecticide containing the neonicotinoid imidacloprid as its active ingredient, on Caenorhabditis elegans. We discovered that “T+S” significantly stunted the overall growth in wildtype nematodes, an effect that was exacerbated by concurrent exposure to heat stress. “T+S” also negatively impacted fecundity as measured by increased germline apoptosis, a decrease in egg-laying, and fewer viable offspring. Lastly, exposure to “T+S” resulted in degenerative changes in nicotinic cholinergic neurons in wildtype nematodes. As a whole, these findings demonstrate widespread toxic effects of neonicotinoids to critical functions in nematodes.