Interactions Of Pesticides Research Articles

Adsorption-desorption mechanisms and migration behavior of fluchlordiniliprole in four different soils under varied conditions

Utilizing infrared spectroscopy coupled with batch equilibrium methods, the adsorption and desorption characteristics of the novel Insecticide fluchlordiniliprole were assessed in four different soil types. It was found that fluchlordiniliprole’s adsorption and desorption in these soils were consistent with the Freundlich isotherm, exhibiting adsorption capacities (KF-ads) ranging from 8.436 to 36.269. Temperature fluctuations, encompassing both high and low extremes, impaired the ability of soil to adsorb fluchlordiniliprole. In addition, adsorption dynamics were modulated by several other factors, including soil pH, ionic strength, amendments (e.g., biochar and humic substances), and the presence of various surfactants and microplastics. Although capable of leaching, fluchlordiniliprole exhibited weak mobility in most soils. Therefore, it appears that fluchlordiniliprole seems to pose a threat to surface soil and aquatic biota, but a minimal threat to groundwater. Synopsis StatementThis research examines the dynamics of fluchlordiniliprole in soil, an will aid in maintaining ecological safety and managing agricultural pesticides. The study's comprehensive analysis of adsorption, desorption, and soil migration patterns significantly contributes to our understanding of pesticide interactions with diverse soil types. The results of this study will enable the development of environmentally responsible agricultural practices.

A novel approach to managing facility airborne diseases: suppressing air pathogens with smoke aerosols generated from fungicide phase transition.

Environmental microorganisms are major contributors to the development and spread of disease. Chemical disinfection can inhibit pathogens and play a preventive role against diseases. In agriculture, prolonging the floating time of chemical pesticides in the air has a positive effect on the control of airborne diseases. However, the interaction of chemical pesticides with airborne pathogens is not yet known. Here, triazole fungicide was transformed into stable smoke aerosols in order to assess the feasibility of employing phase transition release pesticides for air disinfection. The phase transition had a minimal impact on hexaconazole (Hexa) and myclobutanil (Mycl), with their smoke formation rates remaining consistently >90%. In microscopic morphology, triadimenol (Tria) and epoxiconazole (Epox) are solid, and tebuconazole (Tebu), Hexa, Mycl and difenoconazole (Dife) are liquid. Liquid smoke has advantages over solid smoke in the inhibition of environmental pathogens. The floatability and spatial distribution of fungicide aerosol were optimized by the combination of smoke particles with different properties, so that the fungicide aerosol could meet the conditions of practical application. In practical applications, smoke exhibits a gentler deposition process at the target interface compared to spray, along with a more homogeneous distribution of fungicides. Moreover, fungicide smoke demonstrates superior control efficacy and leaves behind lower residual amounts on fruit. In conclusion, the implementation of fungicide phase transition as a smoke aerosol offers a viable approach to effectively suppress pathogen aerosols and enhance the control of airborne diseases. © 2024 Society of Chemical Industry.

Removal of acephate and methamidophos from water: Coagulation and adsorptive treatment approaches

Pesticides has transformed the agricultural industry, primarily by enhancing productivity. However, the indiscriminate use of such compounds can adversely affect human health and disrupt ecosystem balance. Limited knowledge exists regarding the removal of these compounds from water, particularly for organophosphate pesticides when employing conventional treatment technologies. Therefore, this study aimed to assess the removal of acephate (ACE) and methamidophos (MET) - considered priority pesticides in Brazil - from waters with high and low turbidity during the clarification process carried out with aluminum sulfate (AS) and ferric chloride (FC), either alone or combined with powdered activated carbon (PAC) adsorption. All water samples were submitted to solid phase extraction (SPE C18 cartridges) prior to acephate and methamidophos analysis by HPLC MS/MS. The clarification process with either AS or FC coagulant did not efficiently remove acephate or methamidophos and maximum average removal (27 %) was observed with waters of high turbidity when using ferric chloride as coagulant. Addition of mineral PAC was also ineffective for removing both pesticides. However, the use of vegetable PAC (10 mg/L) resulted in better removal percentages, up to 80%, but only for methamidophos. The limited removal rates were attributed to the high hydrophilicity of acephate and methamidophos, along with their neutral charge at coagulation pH. These factors hinder the interaction of such organophosphorus pesticides with the flocs formed during coagulation as well as with PAC surface.

Prediction of Pesticide Interactions with Proteins Involved in Human Reproduction by Using a Virtual Screening Approach: A Case Study of Famoxadone Binding CRBP-III and Izumo.

In recent years, the awareness that pesticides can have other effects apart from generic toxicity is growing. In particular, several pieces of evidence highlight their influence on human fertility. In this study, we investigated, by a virtual screening approach, the binding between pesticides and proteins present in human gametes or associated with reproduction, in order to identify new interactions that could affect human fertility. To this aim, we prepared ligand (pesticides) and receptor (proteins) 3D structure datasets from online structural databases (such as PubChem and RCSB), and performed a virtual screening analysis using Autodock Vina. In the comparison of the predicted interactions, we found that famoxadone was predicted to bind Cellular Retinol Binding Protein-III in the retinol-binding site with a better minimum energy value of -10.4 Kcal/mol and an RMSD of 3.77 with respect to retinol (-7.1 Kcal/mol). In addition to a similar network of interactions, famoxadone binding is more stabilized by additional hydrophobic patches including L20, V29, A33, F57, L117, and L118 amino acid residues and hydrogen bonds with Y19 and K40. These results support a possible competitive effect of famoxadone on retinol binding with impacts on the ability of developing the cardiac tissue, in accordance with the literature data on zebrafish embryos. Moreover, famoxadone binds, with a minimum energy value between -8.3 and -8.0 Kcal/mol, to the IZUMO Sperm-Egg Fusion Protein, interacting with a network of polar and hydrophobic amino acid residues in the cavity between the 4HB and Ig-like domains. This binding is more stabilized by a predicted hydrogen bond with the N185 residue of the protein. A hindrance in this position can probably affect the conformational change for JUNO binding, avoiding the gamete membrane fusion to form the zygote. This work opens new interesting perspectives of study on the effects of pesticides on fertility, extending the knowledge to other typologies of interaction which can affect different steps of the reproductive process.

The Effects of the Interaction of Pesticides with Humin Fraction as Influencing the Sustainable Development of Agroecosystems

Humin (HUM) is the most stable fraction of the soil organic matter, whose properties determine the soil health and sustainable development of agroecosystems. The aim of the paper was to determine changes in the properties of the HUM after interaction with selected pesticides, which can be visualized using photoluminescence methods. The HUM was isolated from the mollic horizon of Phaeozems arable soils derived from different parent materials in Poland. The isolated and purified HUM were saturated in a batch experiment with selected herbicides and insecticides, then analyzed for chemical composition and spectroscopic properties: Electron Paramagnetic Resonance, fluorescence, and delayed luminescence. The research showed that the interaction of the HUM with selected pesticides caused significant changes in the elemental composition of the HUM; however, no changes in their aromaticity/aliphaticity were found. The impact of pesticides was also marked by a reduction in the concentration of radicals, fluorescence and delayed luminescence intensity and properties. Changes in spectroscopic characteristics and their relationship with soil organic matter (SOM) structure properties require further research so that their results can be used in the management of agroecosystems in accordance with the principles of sustainable development.

Revealing the mechanistic interactions of profenofos and captan pesticides with serum protein via biophysical and computational investigations

Profenofos (PF) and captan (CT) are among the most utilized organophosphorus insecticides and phthalimide fungicides, respectively. To elucidate the physicochemical and influential toxicokinetic factors, the mechanistic interactions of serum albumin and either PF or CT were carried out in the current study using a series of spectroscopy and computational analyses. Both PF and CT could bind to bovine serum albumin (BSA), a representative serum protein, with moderate binding constants in a range of 103–104 M−1. The bindings of PF and CT did not induce noticeable BSA’s structural changes. Both pesticides bound preferentially to the site I pocket of BSA, where the hydrophobic interaction was the main binding mode of PF, and the electrostatic interaction drove the binding of CT. As a result, PF and CT may not only induce direct toxicity by themselves, but also compete with therapeutic drugs and essential substances to sit in the Sudlow site I of serum albumin, which may interfere with the pharmacokinetics and equilibrium of drugs and other substances causing consequent adverse effects.

Combined application of up to ten pesticides decreases key soil processes

Natural systems are under increasing pressure by a range of anthropogenic global change factors. Pesticides represent a nearly ubiquitously occurring global change factor and have the potential to affect soil functions. Currently the use of synthetic pesticides is at an all-time high with over 400 active ingredients being utilized in the EU alone, with dozens of these pesticides occurring concurrently in soil. However, we presently do not understand the impacts of the potential interaction of multiple pesticides when applied simultaneously. Using soil collected from a local grassland, we utilize soil microcosms to examine the role of both rate of change and number of a selection of ten currently used pesticides on soil processes, including litter decomposition, water stable aggregates, aggregate size, soil pH, and EC. Additionally, we used null models to enrich our analyses to examine potential patterns caused by interactions between pesticide treatments. We find that both gradual and abrupt pesticide application have negative consequences for soil processes. Notably, pesticide number plays a significant role in affecting soil health. Null models also reveal potential synergistic behavior between pesticides which can further their consequences on soil processes. Our research highlights the complex impacts of pesticides, and the need for environmental policy to address the threats posed by pesticides.

Identification of molecular interactions of pesticides with keratinase for their potential to inhibit keratin biodegradation.

Illustration depicting the hypothesis, experimental procedure, and the resultant keratinase-inhibitory potential of selected pesticides.

Microbe-pesticide interactions: Soil enzyme analysis and bacterial degradation of chlorpyrifos

With the objective of understanding microbe—pesticide interactions in soil, the effect of pesticides alone and in combination on the activities of amylase, cellulase, and invertase was assessed in black, and red soils collected from the groundnut (Arachis hypogaea L.) cultivated fields of Andhra Pradesh, India. In addition, the potential bacteria that can break down chlorpyrifos was identified using biochemical assays and a partial 16S rRNA gene sequence analysis. Soil enzymes were analyzed using standard procedures described elsewhere. The activities of amylase, cellulase, and invertase were solely dependent on the dose of pesticides used in the current study. Enzyme activities were significantly increased at the level of 2.5 or 5.0 kg ha–1, whereas increases in the concentration of pesticides at 7.5–10 kg ha−1 were lethal to the enzyme activities in both soils at 10-day incubation. The effective combination for the increase in the activities of amylase, cellulase, and invertase were monocrotophos + mancozeb. Mineral salts medium with 50 ppm chlorpyrifos as a carbon source had the greatest growth of the bacteria (i.e. Pseudomonas citronellolis strain CF3) at 14th h of incubation with OD value of 0.24 at 660 nm, and the same strain could eliminate 75% of the chlorpyrifos within 24 h from the medium. Based on the present study it was concluded that insecticides used alone or in combination with fungicides at specific doses (2.5 or 5.0 kg ha−1) improved the amylase, cellulase, and invertase activities, which are involved in the carbon cycle in soils. Pseudomonas citronellolis strain CF3 is a potential bacterium in the remediation of chlorpyrifos-contaminated sites.

The Interaction of Pesticides with Humin Fractions and Their Potential Impact on Non-Extractable Residue Formation.

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

Interaction of Pesticides with Clean-up Agents during QuEChERS Dispersive-SPE Clean-up

Interaction of Pesticides with Clean-up Agents during QuEChERS Dispersive-SPE Clean-up

Identification of coastal pesticide pollutants as potent inhibitors of Bacillus pasteurii urease mediated calcium carbonate precipitation: a computational approach

Microbially induced calcite precipitation (MICP) through urease enzyme has attained a lot of recognition in various fields of civil engineering and geotechnology for stabilizing the strength of soil and various concrete materials. The activity of urease has been found to be affected by various factors like temperature, substrate concentrations, pH of the medium, presence of inhibitors, etc. Through this study, the outcome of the interaction of pesticides (commonly found in Indian coastal regions) on Bacillus pasteurii urease, a major organism reported for MICP studies has been investigated in silico. The results from the study revealed that the enzyme has higher interactions of −4.1, −3.2, and −3.4 kJ/mol with common pesticides like dichloro diphenyl dichloro ethane(DDD), dichloro diphenyl trichloroe thane (DDT), and methyl parathion of organochlorides and organophosphates class. From the molecular dynamics simulation analysis, complex 1 (DDD -receptor) has been found to have the highest and more compact structure followed by methyl parathion -receptor. Prime MM-GBSA analysis also revealed the highest binding energy of −27.8 kcal/mol with the protein and DDD. Thus, it can be inferred from the current study that pesticides, particularly, DDD, DDT, and methyl parathion present in the coastal areas may have an impact on urease. This interaction can result in the inhibition of the urease activity of B. pasteurii, thus preventing the biomineralization process. This study would be the first report on the computational approach to understanding the interaction of prominent pesticides on the coastal region and B. pasteurii urease. Communicated by Ramaswamy H. Sarma

Competitive formation of molecular inclusion complexes of chlordecone and β-hexachlorocyclohexane with natural cyclodextrins: DFT and molecular dynamics study.

Chlordecone (CLD) and β-hexachlorocyclohexane (β-HCH) are chlorinated pesticides that coexist as persistent organic pollutants in the groundwater of several countries in the Caribbean, being an environmental issue. This work evaluates theoretically the competitive formation of host-guest complexes pesticides@cyclodextrines (CDs) as an alternative for water purification and selective separation of pesticides. Quantum mechanical calculations based on density functional theory (DFT) and classical molecular dynamics (MD) simulations were used to achieve information on geometries, energies, structure, and dynamics of guest-host complexes in the gas phase, implicit solvent medium, and in aqueous solutions. DFT studies showed that interactions of both pesticides with CDs are mediated by steric factors and guided by maximization of the hydrophobic interactions either with the other pesticide or with the CD cavity's inner atoms. MD results corroborate the formation of stable complexes of both pesticides with the studied CDs. α-CD exhibited a preference for the smaller β-HCH molecule over the CLD that could not perturb the formed complex. The simulation of competitive formation with γ-CD illustrated that this molecule could accommodate both pesticides inside its cavity. These results suggest that CDs with smaller cavity sizes such as α-CD could be used for selective separation of β-HCH from CLD in water bodies, while γ-CD could be used for methods that aim to remove both pesticides at the same time.

Ratiometric Sensing of Glyphosate in Water Using Dual Fluorescent Carbon Dots.

Glyphosate is a broad-spectrum pesticide used in crops and is found in many products used by industry and consumers. Unfortunately, glyphosate has been shown to have some toxicity toward many organisms found in our ecosystems and has been reported to have carcinogenic effects on humans. Hence, there is a need to develop novel nanosensors that are more sensitive and facile and permit rapid detection. Current optical-based assays are limited as they rely on changes in signal intensity, which can be affected by multiple factors in the sample. Herein, we report the development of a dual emissive carbon dot (CD) system that can be used to optically detect glyphosate pesticides in water at different pH levels. The fluorescent CDs emit blue and red fluorescence, which we exploit as a ratiometric self-referencing assay. We observe red fluorescence quenching with increasing concentrations of glyphosate in the solution, ascribed to the interaction of the glyphosate pesticide with the CD surface. The blue fluorescence remains unaffected and serves as a reference in this ratiometric approach. Using fluorescence quenching assays, a ratiometric response is observed in the ppm range with detection limits as low as 0.03 ppm. Our CDs can be used to detect other pesticides and contaminants in water, as cost-effective and simple environmental nanosensors.

Correlation of pesticide ecotoxicity with clay mineral dispersion effect on adsorption and ozonation – An approach through impact assessment on Lemna minor

An unprecedented approach allowed correlating the pesticide fate in clay-containing media under air exposure with their ecotoxicity. This constitutes the novelty of this work and involves the study of the toxicity of ozonized pesticide-containing waters towards an aquatic plant, Lemna minor. The behavior of diazinon (DAZ) and atrazine (ATR) in natural clay-containing media was simulated in plant growth media fulfilling the Swedish Institute for Standards (SIS) containing Na+ and Fe2+-exchanged montmorillonite (Mt). The exchangeable cation was found to influence the pesticide ozonation and toxicity towards Lemna minor. Pesticide interactions appear to promote high catalytic surface through a compromise between low pH and high Mt dispersion. These results provide valuable findings for predicting pesticide ecotoxicity according to their natural oxidative degradation in the host clay suspension.

Influence of co-exposure to sulfamethazine on the toxicity and bioaccumulation kinetics of chlorpyrifos in zebrafish (Danio rerio)

Pesticides and antibiotics are frequently present in aquatic environment which may pose potential risks to aquatic organisms. However, the interaction of pesticides and antibiotics in co-exposure model remains unclear. Here, the effects of the co-exposure of sulfamethazine (SMZ) on the toxicity and bioaccumulation of the organophosphorus insecticide chlorpyrifos (CPF) in zebrafish (Danio rerio) were explored. The 96-h LC50 of chlorpyrifos to zebrafish was 1.36 mg/L and sulfamethazine at 1 mg/L slightly increased the acute toxicity with the 96-h LC50 of 1.20 mg/L which was not significant. The 30-day co-exposure of chlorpyrifos with sulfamethazine at 1 mg/L aggravated the oxidative stress, decreased CarE and AChE activity, and increased CYP450 activity significantly. Furthermore, the co-exposure reduced the accumulation of chlorpyrifos and sulfamethazine while prolonged their depuration duration. The results demonstrated the exposure risk of chlorpyrifos to zebrafish may be enhanced in the presence of sulfamethazine.

Interactions of organophosphorus pesticides with ATP-binding cassette (ABC) drug transporters

Although pharmaceutical companies have to study drug-transporter interaction, environmental contaminant interactions with these transporters are not well characterised. In this study, we demonstrated using in vitro transfected cell line that some organophosphorus pesticides are able to interact with drug efflux transporters like P-glycoprotein, BCRP and MRPs. According to our results, dibrom was found to inhibit only Hoechst binding site of P-gp with an IC50 closed to 77 µM, phosmet inhibited BCRP efflux with an IC50 of 42 µM and only profenofos was able to inhibit BCRP, MRPs and P-gp at two binding sites. As profenofos appeared to be a potent ABC transporter inhibitor, we studied its potential substrate property towards P-gp. Using a docking approach, we developed an in silico tool to study pesticide properties to be a probe or inhibitor of P-gp transporter. From both in silico and in vitro results, profenofos was not considered as a P-gp substrate. Combining both in vitro and docking methods appears to be an attractive approach to select pesticides that would not pass into the blood systemic circulation.

Interaction between Thiamethoxam and Deformed Wing Virus Type A on Wing Characteristics and Expression of Immune and Apoptosis Genes in Apis mellifera.

Simple SummaryHoney bees are key pollinators in agricultural crops. Today, honey bee colonies in decline are a global concern as a result of various stressors, including pesticides, pathogens, honey bee health, and parasites. A healthy honey bee colony refers to colonies that are not exposed to biotic and abiotic stressors. In this study, we examine how thiamethoxam (pesticide) and deformed wing virus type A (DWV-A) interact in effects on honey bee health. The results revealed that the honey bees were infected with DWV-A and were additionally exposed to thiamethoxam, showing effects that increased the mortality rate, and crippled wings in newly emerged adult honey bees. Moreover, the exposure to thiamethoxam and DWV-A injection resulted in induced expression of immune genes (hymenoptaecin gene) while downregulation of two apoptosis genes (caspase8-like, caspase9-like genes). The impact interaction of pesticide and DWV-A have on the expression of apoptosis genes can directly affect viral susceptibility in the honey bee host.Honey bees are economically important insects for crop pollination. They play a significant role as pollinators of wild plants and agricultural crops and produce economical products, such as honey, royal jelly, wax, pollen, propolis, and venom. Despite their ecological and economical importance, the global honey bee population is in decline due to factors including pathogens, parasites, intensive agriculture, and pesticides. Moreover, these factors may be interlinked and exacerbate the loss of honey bees. This study aimed to investigate the interaction between a pesticide, thiamethoxam, and deformed wing virus type A (DWV-A) to honey bees and the effects on survival rate, wing characteristics, and expression of immune and apoptosis genes in Apis mellifera. We described the potential interaction between thiamethoxam and DWV-A on honey bee wing characteristics, DWV-A loads, and the expressions of immune (defensin, abaecin, and hymenoptaecin) and apoptosis genes (buffy, apaf1, caspase3-like, caspase8-like, and caspase9-like). Honey bee larvae were fed with three different thiamethoxam doses (0.001, 1.4, and 14.3 ng/µL of the diet). Then, thiamethoxam-treated white-eyed pupae were injected with 107 copy numbers/honey bee of the DWV-A genome. The interaction between thiamethoxam and DWV-A caused a high mortality rate, crippled wings in newly emerged adult honey bees (100%), and resulted in induced expression of hymenoptaecin gene compared to the control group, while downregulation of caspase8-like, caspase9-like genes compared to the DWV injection group. Therefore, the potential interaction between thiamethoxam and DWV-A might have a deleterious effect on honey bee lifespan. The results from this study could be used as a tool to combat DWV-A infection and mitigate pesticide usage to alleviate the decrease in the honey bee population.

Investigation on the interaction of pyrethroid pesticides to estrogen receptor alpha through computational and experimental methods

Pyrethroid insecticides are a group of widely used bio-mimetic synthetic pesticides. However, recent studies reported that they could have an accumulation effect in human which may cause series of health problems. Estrogen receptors (ER) are a class of nuclear receptors that are vital in proper physiological behavior of estrogens. To investigate the reproductive toxicity of pyrethroids, homology modeling, molecular docking, molecular dynamic simulations (MDs) were conducted to explore the interaction between pyrethroids and ERα from atomic scale. The human ERα (2YJA) was selected as a template protein for homology modeling. Then eight typical pyrethroids and positive control estradiol were docked to the modeled protein. The highest scoring bifenthrin and the lowest scoring permethrin were chosen for in-depth analysis. MDs showed that the complex formed by permethrin with ERα had a lower RMSD value and binding free energies compared to bifenthrin. Based on these results from microscopic dimension, exposure experiments were implemented to validate the primary conclusions. VTG concentrations in male zebrafish’s blood were significantly higher under permethrin exposure than bifenthrin, suggesting a stronger estrogenic activity and binding propensity. In this regard, the structural characteristics of molecules were analyzed, expecting to provide theoretical references for subsequent drug design and rational drug application.

Cytotoxicity and Genotoxicity of Imidacloprid, Spinosad and Bifenthrin - Myclobutanil Combination to Allium cepa Root Tip Meristematic Cells

Pesticides use boosts agricultural yield by reducing crop losses. However, some pesticides are mutagens and while technical grade active ingredients may produce mixed results in cytotoxicity and mutagenicity tests in in vitro and in vivo assays, synergistic interaction of pesticides, their metabolites or impurities in pesticide formulations often produce cytotoxic and genotoxic effects. This study assessed three concentrations (mg mL-1) (0.04, 0.08 and 0.16) each of Aphicide Plus® (AP) (imidacloprid at 20g L-1); Eco Fruit-fly Bait GF120® (EF) (spinosad at 0.24 g L-1) and Rosecare 3® (RC3) (combination of bifenthrin at 2.0 g L-1 and myclobutanil at 7.5 g L-1) for their effect on the (P+M)/ (A+T) Ratio, cytotoxicity and genotoxicity using the Allium cepa assay. A. cepa seedlings were treated for 24 hours, root tip squashes were prepared and the slides were examined under the microscope. For each pesticide treatment and the negative control, 6000 cells were examined and the cells were classified into interphase, normal (N) or aberrant (ABN) mitotic division stage. The cytotoxicity and genotoxicity induced by each pesticide concentration was compared with the value for the negative control using t-test. The 0.08 mg mL-1 of AP, 0.04 mg mL-1 of EF, and 0.08 and 0.16 mg mL-1 of RC3 induced significant change in the (P+M)/(A+T) ratio, (p > 0.05). All three concentrations of each pesticide significantly depressed the mitotic index (MI) and were adjudged cytotoxic (P < 0.05). Genotoxicity (GT) was expressed as the number of aberrant mitotic cells (AMC) per 100 mitotic cells scored. The three concentrations of each pesticide induced genotoxicity (P < 0.05). Pesticides use boosts agricultural yield by reducing crop losses. However, some pesticides are mutagens and while technical grade active ingredients may produce mixed results in cytotoxicity and mutagenicity tests in in vitro and in vivo assays, synergistic interaction of pesticides, their metabolites or impurities in pesticide formulations often produce cytotoxic and genotoxic effects. This study assessed three concentrations (mg mL-1) (0.04, 0.08 and 0.16) each of Aphicide Plus® (AP) (imidacloprid at 20g L-1); Eco Fruit-fly Bait GF120® (EF) (spinosad at 0.24 g L-1) and Rosecare 3® (RC3) (combination of bifenthrin at 2.0 g L-1 and myclobutanil at 7.5 g L-1) for their effect on the (P+M)/ (A+T) Ratio, cytotoxicity and genotoxicity using the Allium cepa assay. A. cepa seedlings were treated for 24 hours, root tip squashes were prepared and the slides were examined under the microscope. For each pesticide treatment and the negative control, 6000 cells were examined and the cells were classified into interphase, normal (N) or aberrant (ABN) mitotic division stage. The cytotoxicity and genotoxicity induced by each pesticide concentration was compared with the value for the negative control using t-test. The 0.08 mg mL-1 of AP, 0.04 mg mL-1 of EF, and 0.08 and 0.16 mg mL-1 of RC3 induced significant change in the (P+M)/(A+T) ratio, (p > 0.05). All three concentrations of each pesticide significantly depressed the mitotic index (MI) and were adjudged cytotoxic (P < 0.05). Genotoxicity (GT) was expressed as the number of aberrant mitotic cells (AMC) per 100 mitotic cells scored. The three concentrations of each pesticide induced genotoxicity (P < 0.05).