Dissipation kinetics and consumer risk assessment of novaluron + lambda-cyhalothrin co-formulation in cabbage

Dissipation and Risk Assessment of Propaquizafop in Ginseng under Field Conditions

Propaquizafop is a highly efficient aryloxy phenoxy propionate chiral herbicide. However, the use of propaquizafop, including its safe use methods, residue patterns, dietary risk assessment, and maximum residue limits, for ginseng, a traditional Chinese medicinal plant, has not been studied. An analytical method was established for the simultaneous determination of propaquizafop and its four metabolites in ginseng soil, fresh ginseng, ginseng plant, and dried ginseng using HPLC-MS/MS. This approach showed good linearity (R2 ranging from 0.9827 to 0.9999) and limit of quantification ranging from 0.01 to 0.05 mg/kg. The intra- and interday recovery rates of this method ranged from 71.6 to 107.1% with relative standard deviation ranging from 1.3 to 23.2%. The method was applied to detect residual samples in the field, and it was found that the degradation of propaquizafop in ginseng plants and soil followed a first-order kinetic equation. R2 was between 0.8913 and 0.9666, and the half-life (t1/2) ranged from 5.04 to 8.05 days, indicating that it was an easily degradable pesticide (T1/2 < 30 days). The final propaquizafop residues in ginseng soil, plants, fresh ginseng, and dried ginseng ranged from 0.017 to 0.691 mg/kg. A dietary risk assessment was conducted on the final propaquizafop residue in fresh and dried ginseng. The results showed that the chronic exposure risk quotient values were less than 100% for fresh and dried ginseng (1.15% for fresh ginseng and 1.13% for dried ginseng). This illustrates that the dietary risk associated with the use of 10% propaquizafop emulsifiable concentrate in ginseng is very low. Thus, applying 750 mL/ha of propaquizafop on ginseng could not pose an unacceptable risk to public health. The results of the present study support the registration of propaquizafop in ginseng.

Dissipation behaviours, residues, and health risk of six herbicides in sugar beets under field conditions

This study established a residue detection method based on the QuEChERS pre-treatment method and combined it with high-performance liquid chromatography-tandem mass spectrometry to test six herbicides (metamitron, clopyralid, desmedipham, phenmedipham, ethofumesate, and haloxyfop-p-methyl) in sugar beet plants, soil, and roots. The degradation dynamics and terminal residues of each herbicide in sugar beets were analysed. Finally, the dietary risks of various herbicides in sugar beets were evaluated based on the dietary structure of Chinese people, and the risk quotient values were below 100%. Using this detection method, all reagents exhibited good linearity (0.9724 ≤ R2 ≤ 0.9998), The limit of quantification (LOQ) ranged from 0.01 to 0.05 mg/L, the matrix effect ranged from -1.2% to -50%, the addition recovery rate ranged from 77.00% to 103.48%, and the relative standard deviation ranged from 1.61% to 16.17%; therefore, all indicators of this method met the residue detection standards. Under field conditions, the half-lives (t1/2) ranged about 0.65 ∼ 2.96 d and 0.38 ∼ 27.59 d in sugar beet plants and soil, respectively. All herbicides were easily degraded in sugar beet plants and soil (t1/2 < 30 d). The terminal residue amounts in the beet plants, soil, and roots ranged from < LOQ to 0.243 mg/kg. The dietary risk assessment of each pesticide was conducted based on the residual median of the terminal residues and the highest residual values on the edible part of the beetroot. The chronic exposure risk quotient (RQc) and acute exposure risk quotient (RQa) values were < 100%, indicating that the residue of each pesticide in beetroot posed low risks to consumers in China at the recommended dosage.

Residue estimation and dietary risk assessment of fenvalerate, novaluron, and profenofos in bell pepper grown under protected and open field conditions

Residue studies were conducted in bell pepper crops (green and yellow bell pepper) to ensure the safe use of fenvalerate, profenofos, and novaluron (under open field and protected conditions) in randomized block design (RBD) following three applications at a 10-day interval over two consecutive years, 2021 and 2022. A robust analytical method was developed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) for the determination of pesticide residues in bell pepper samples. The half-lives for fenvalerate were 2.47-2.87 and 2.50-3.03 days on bell pepper under open field conditions, whereas the corresponding values for bell pepper under protected conditions were 3.84-4.58 and 4.17-4.71 days, during 2021 and 2022, respectively. Profenofos displayed half-lives of 2.03-2.65 and 2.15-2.77 days in open field conditions and 3.05-3.89 and 3.16-3.78 days in protected conditions during 2021 and 2022, respectively. Similarly, novaluron had half-lives of 2.87-3.49 and 3.24-3.75 days under protected conditions in 2021 and 2022, respectively. The maximum residue limits (MRLs) were calculated to be 0.6 mg/kg for fenvalerate, while for profenofos it was 0.7 mg/kg on bell pepper under open field conditions at double doses, at the proposed pre-harvest interval (PHI) of 3 days. Likewise, for bell peppers grown under protected conditions, MRLs at the PHI of 3 days were determined to be 0.8 mg/kg for fenvalerate, 0.3 mg/kg for novaluron, and 1.5 mg/kg for profenofos. A dietary risk assessment study indicated that the percentage of acute hazard index (% aHI) was significantly lower than 100, and hazard quotient (HQ) values were below 1, signifying no acute or chronic risk to consumers. These findings underscore the safety of consuming bell peppers treated with fenvalerate, profenofos, and novaluron under the protected and open field conditions.

Persistence and dissipation kinetics of novaluron 9.45% + lambda-cyhalothrin 1.9% ZC insecticides in tomato crop under semi-arid region

In recent decades, fate studies of pesticides have been a topic of interest worldwide due to human health concerns tomato, contain abundant nutritional phytochemicals and lycopene which is known for antioxidant. Tomato is susceptible to many pest, so to overcome from these pests many insecticides are used, leaving residual effects on the crop. So to find out the persistence, the present study was carried out to investigate the residual levels and dissipation behaviour of novaluron 9.45% + lambda-cyhalothrin 1.9% ZC in tomato crop during Rabi session of 2017-18 in randomized block design. The first spray of insecticide was done at fruit formation stage and second spray at 10-day interval at recommended dose @43.31 g a.i. ha-1 and double of recommended dose @86.62 g a.i. ha-1. The residue of novaluron determined by HPLC (high-performance liquid chromatography) on 0 day (two hours after spraying) was 0.154 ppm at lower dose and 0.234 ppm at higher dose. The residue of lambda-cyhalothrin determined by GC ECD (gas chromatography electron capture detector) at 0 day (two hours after spraying) was 0.451 ppm at lower dose and 0.849 ppm at higher dose. The deposition of novaluron 9.45% +  lambda-cyhalothrin 1.9% ZC was gradually decreased with increasing days after spraying (DAS). The mean initial deposition of the pesticide novaluron and lambda-cyhalothrin was recorded as 0.154 mg/kg, 0.451 mg/kg, respectively, at the recommended dose @43.31 g a.i. ha-1 while at double of recommended dose @86.62 g a.i. ha-1 novaluron and lambda-cyhalothrin, the mean initial deposition of 0.234 mg/kg and 0.849 mg/kg was recorded, respectively. The residue of the novaluron and lambda-cyhalothrin was at BDL (below determination level) (0.01 and 0.05 ppm) on 5th and 7th day, respectively, at lower dose (x), whereas at higher dose (2x) it was below determination level on 7th and 10th day, respectively. In soil samples, the residue levels were at below the determination level (0.01 mg/kg) for novaluron and (0.05 mg/kg) for lambda-cyhalothrin at both doses. The half-life DT50 of novaluron and lambda-cyhalothrin in the tomato fruit was found to be 2 days at recommended dose (X) @43.31 g a.i. ha-1 for both the pesticide and at double of the recommended dose @86.62 g a.i. ha-1 it was 3 and 2 days, respectively.

Residue dynamics and dietary risk assessment of new formulation of novaluron and lambda cyhalothrin on tomato

Presence of residues on food commodities is major bottleneck of insecticide use under good agricultural practices (GAPs). The use of less persistent with two different mode of action insecticide is novel approach of getting maximum insect control without developing insecticide resistance. Novaluron, an insect growth disruptor and lambda cyhalothrin, a nerve poison has been used widely for the management of lepidopteran pests. Dissipation and consumer risk analysis studies were carried out on a new combination product of novaluron and lambda cyhalothrin are used for control insects of tomato at recommended standard dose of 71 + 14 g/ha and double dose of 142 + 28 g/ha of active ingredients. Extraction and cleanup of sample residues was done using QuEChERS technique and analyzed in GC-ECD. The residues of novaluron were dissipated within 10 to 15 days, and the residues of lambda cyhalothrin were at 7 to 10 days, both at the standard and double the standard dose, following a first order reaction kinetics. Analysis of risk and hazard quotient revealed that the test insecticides do not pose any dietary risk to consumer as TMDI < MPI and HQ < 1.

Simultaneous monitoring and dietary risk assessment of 386 pesticides in market samples of black tea

Black tea samples (390) collected from local markets situated in different locations of India were monitored for the residues of 386 pesticides using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) based extraction and analysis by gas and liquid chromatography tandem mass spectrometry (GC-MS/MS and LC-MS/MS). Residues of seventeen pesticides were detected, of which propargite, cypermethrin, and novaluron showed the highest % positive detections. A comparison of the concentrations of the detected pesticide residues with the available national and international maximum residue limits (MRLs) showed that seven samples exceeded the Indian MRLs while no sample was found to exceed the CODEX MRLs. The risk due to the detected pesticide levels evaluated in terms of hazard quotient (HQ) and hazard index (HI) was found to be very low (<1), suggesting that the pesticide residues in the tea were safe for consumption by Indian adults and children.

Dissipation kinetics of co-formulation with two herbicides, clodinafop-propargyl and oxyfluorfen, in/on onion (Allium cepa) samples

Supervised field trail on dissipation of co-formulation with herbicides clodinafop-propargyl and oxyfluorfen in spring onion showed similar pattern of dissipation during two different seasons. Residues of clodinafop-propargyl reached ≤ limit of quantitation (LOQ, 0.05 mg kg^-1) on 3rd day after application at both standard and double dose during both the seasons. Oxyfluorfen residues followed first-order kinetics in both the doses during first season with half-life of 0.81 to 3.14 days. The residues of clodinafop-propargyl were detected in soil at both the doses during first season. However, residues were ≤ LOQ (0.05 mg kg^-1) during second season. The residues of oxyfluorfen were detected only in double dose during first season in soil. In all other cases and in onion bulb, residues were ≤ LOQ (0.05 mg kg^-1) at the time of harvest. As the residues were either ≤ LOQ (0.05 mg kg^-1) on 3rd day or have a half-life of 3.14 days, the co-formulation can be used safely, provided a pre harvest interval (PHI) of 3 days is followed. On the basis of maximum residue limits (MRLs) in other commodities and from the data of present study, a default MRL of 0.05 mg kg^-1 is proposed for both the pesticides.

Dissipation kinetics of some pesticides applied singly or in mixtures in/on grape leaf

BACKGROUND

Grape and leaf quality are often severely reduced by fungi such as grey rot Botrytis cinerea Pers., powdery mildew Erysiphe necator Schwein, and downy mildew Plasmopara viticola (Berk. & M.A.Curtis) Berl. & De Toni and by insects such as Otiorhynchus spp., European grapevine moth Lobesia botrana Den.-Schiff., vine mealybug Planococcus citri Risso, and grape erineum mite Colomerus vitis Pgst. Various pesticides are often applied to mitigate these pest problems. These chemicals used singly as well as in the form of a mixture can leave residues on or in the crop. It is therefore of great importance to study the dissipation of the pesticides applied alone and in mixtures to this crop to protect consumers.

RESULTS

The dissipation kinetics of cypermethrin, boscalid, deltamethrin, kresoxim-methyl, lambda-cyhalothrin, metalaxyl-M, metrafenone, and triadimenol residues were studied in vine leaves grown under sunny conditions in Turkey. The dissipation rate for singly applied pesticides followed first-order kinetics, with half-lifes in grape leaves in the range of 1.85-7.22 days. Changes in the degradation process of pesticide residues were determined after application, as both single applications and mixtures. The degradation of boscalid, cymoxanil, deltamethrin and metalaxyl-M accelerated while the degradation of cypermethrin, kresoxim-methyl, and lambda-cyhalothrin slowed down in mixtures of pesticides.

CONCLUSION

The use of pesticides in mixtures leads to slower degradation and higher residues for some active ingredients and faster degradation and fewer residues for other active ingredients. Therefore, pesticide mixtures should not be applied in the field without having detailed information about their ingredients. © 2022 Society of Chemical Industry.

Effects of plant morphology, vitamin C, and other co-present pesticides on the deposition, dissipation, and metabolism of chlorothalonil in pakchoi

Pesticide residues have been a focus of attention of food safety. Different varietal pakchoi plants grown in open fields were studied to understand effects of morphology, leaf wax content, and vitamin C on the deposition, dissipation, and metabolism of chlorothalonil. The loose pakchoi plants and flat leaves were conducive to pesticide deposition, but not plants with erect leaves. Chlorothalonil on nine varieties of pakchoi dissipated in the first-order kinetic with T1/2 s of 1.4 ~ 2.0 days. Vitamin C in pakchoi could promote the dissipation of chlorothalonil. Carbendazim could significantly promote the dissipation of chlorothalonil on pakchoi. Interestingly, four metabolites of chlorothalonil were identified in the pakchoi and the metabolic pathway was predicted by DFT calculations. The risk assessment showed that pakchoi were safe for consumption after 10 days of application of the recommended dose. This work provides important information for the understanding of deposition, dissipation, and metabolism of chlorothalonil in pakchoi.

Foliar application of lambda-cyhalothrin modulates root exudate profile and the rhizosphere bacteria community of dioecious Populus cathayana

Dioecious plants show sexual differences in resistance traits to abiotic stresses. However, the effects of exogenous pesticide application on female and male plant growth and their associated adaptation mechanisms are unclear. Our study investigated the effects of the broad-spectrum pesticide lambda-cyhalothrin (λ-CY) on dioecious Populus cathayana growth and explored the factors through which λ-CY changed the rhizosphere bacterial community and physicochemical soil properties via sex-specific metabolomics. The sequential application of λ-CY significantly suppressed male shoot- and root biomass, with little effect on the growth of females. Females possessed a higher intrinsic chemo-diversity within their root exudates, and their levels of various metabolites (sugars, fatty acids, and small organic acids) increased after exposure to λ-CY with consequences on bacterial community composition. Maintaining high bacterial alpha diversity and recruiting specific bacterial groups slowed down the loss of rhizosphere nutrients in females. In contrast, the reduction in bacterial alpha diversity and network structure stability in males was associated with lower rhizosphere nutrient availability. Spearman's correlation analysis revealed that several bacterial groups were positively correlated with the root secretion of lipids and organic acids, suggesting that these metabolites can affect the soil bacterial groups actively involved in the nutrient pool. This study provided novel insights that root exudates and soil microbial interactions may mediate sex-specific differences in response to pesticide application.

Persistence evaluation of fluopyram + tebuconazole residues on mango and pomegranate and their risk assessment

The persistence of combination formulation of fluopyram 200 + tebuconazole 200-400 SC was evaluated across different agro-climates in India for the management of fungal diseases in two commercially important fruit crops, mango and pomegranate. The residues were extracted using quick easy cheap effective rugged and safe (QuEChERS) method and quantification was done on liquid chromatography-tandem mass spectrometry (LC-MS/MS). The fungicide degradation followed 1st-order kinetics and the half-lives were 2.9-6.4 days for mango, and 3.5-7.4 days for pomegranate for both the fungicides. On the basis of Organisation for Economic Co-operation and Development (OECD) maximum residue limit (MRL) calculation, 1.0 mg kg^-1 MRL was obtained for fluopyram while for tebuconazole, it was 0.5 mg kg^-1 on mango, at the pre-harvest interval (PHI) of 5 days. For pomegranate, the respective MRLs were 1.0 mg kg^-1 and 0.7 mg kg^-1 at PHI of 7 days. The dietary risk assessment study indicated that % acceptable daily intake (% ADI) and % acute reference dose (% ARfD) were much lower than 100; thus, the application of fluopyram and tebuconazole on mango and pomegranate is unlikely to present public health concern.

Dissipation of imidacloprid and its metabolites in Chinese prickly ash (Zanthoxylum) and their dietary risk assessment

Dissipation of imidacloprid (IMI) and its metabolites (urea, olefin, 5-hydroxy, guanidine, 6-chloronicotinic acid) in Chinese prickly ash (CPA) was investigated using QuEChERS combined with UPLC-MS/MS. Good linearity (r² ≥0.9963), accuracy (recoveries of 71.8-104.3%), precision (relative standard deviations of 0.9-9.4%), and sensitivity (limit of quantification ≤0.05 mg kg^-1) were obtained. After application of IMI at dosage of 467 mg a.i. L^-1 for three times with interval of 7 d, the dissipation dynamics of IMI in CPA followed first-order kinetics, with half-life of 6.48-7.29 d. IMI was the main compound in CPA, followed by urea and guanidine with small amounts of olefin, 5-hydroxy, and 6-chloronicotinic acid. The terminal residues of total IMI and its metabolites at PHI of 14-21 d were 0.16-7.80 mg kg^-1 in fresh CPA and 0.41-10.44 mg kg^-1 in dried CPA, with the median processing factor of 3.62. Risk assessment showed the acute (RQa) and chronic dietary risk quotients (RQc) of IMI in CPA were 0.020-0.083% and 0.052-0.334%, respectively. Based on the dietary structures of different genders and ages of Chinese people, the whole dietary risk assessment indicated that RQc was less than 100% for the general population except for 2- to 7-year-old children (RQc of 109.9%), implying the long-term risks of IMI were acceptable to common consumers except for children.

Determination of five pesticides in kumquat: Dissipation behaviors, residues and their health risk assessment under field conditions

The present study was carried out to profile the dissipation patterns and residues of five pesticides (triazophos, profenofos, chlorpyrifos, etoxazole and bifenthrin) on kumquat using QuEChERS method coupled with HPLC-MS/MS. The corresponding dietary health risks were also estimated. In the method validation, satisfactory results of good linearity (r2 ≥ 0.9956), sensitivity (limits of quantification ≤0.01 mg/kg), recoveries (71.0-95.7%) with relative standard deviations (0.70-9.4%) were obtained. The half-lives of the five pesticides in kumquat were 13.6-38.5 d under field conditions according to first-order kinetics. Based on the final residue experiment, dietary exposure risks of profenofos, chlorpyrifos, etoxazole and bifenthrin were all acceptably low, with RQc and RQa values of 0.00199-0.122 and 0.00145-0.200, respectively. However, exposure intake of triazophos posed unacceptable acute and chronic health risks for Chinese residents, especially for children with RQa and RQc up to 4.25 and 2.19. Forbidden use suggestion of triazophos and recommended MRLs of profenofos and bifenthrin were put forward in kumquat for safe production and consumption. This work was significant in providing guidance on appropriate application and MRL establishment of pesticides in kumquat.

Long-term monitoring of 155 multi-class pesticide residues in Indian vegetables and their risk assessment for consumer safety

A systematic long-term study was conducted to monitor the pesticide residues in commercially important vegetables that are produced, consumed, and exported from India. Residues of 155 commonly used pesticides were determined in 966 samples of cabbage, green chilli, and okra grown in North and North-Western part of India. The residues were extracted using modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method and quantified by gas chromatography-mass spectrometry and liquid chromatography tandem-mass spectrometry. Acetamiprid, cypermethrin, imidacloprid, metalaxyl, and profenofos were the most frequently detected pesticides. No pesticide was detected in 94.4% cabbage, 34.5% green chilli, and 61% okra samples. The chronic risk assessment due to the dietary exposure of the pesticides was evaluated for Indian adult and child. The results suggested that the detected residue levels in vegetables were within safe limits and their consumption will not pose any dietary risk to the consumers.

Dissipation and Distribution of Picarbutrazox Residue Following Spraying with an Unmanned Aerial Vehicle on Chinese Cabbage (Brassica campestris var. pekinensis)

We assessed the residual distribution and temporal trend of picarbutrazox sprayed by agricultural multicopters on Chinese cabbage and considered fortification levels and flying speeds. In plot 2, 14 days after the last spraying, the residues decreased by ~91.3% compared with those in the samples on day 0. The residues in the crops decreased by ~40.8% of the initial concentration owing to growth (dilution effect) and by ~50.6% after excluding the dilution effect. As the flight speed increased, picarbutrazox residues decreased (p < 0.05, least significant deviation [LSD]). At 2 m s⁻¹ flight speed, the residual distribution differed from the dilution rate of the spraying solution. The average range of picarbutrazox residues at all sampling points was 0.007 to 0.486, below the limit of quantitation −0.395, 0.005–0.316, and 0.005–0.289 mg kg⁻¹ in plots 1, 2, 3, and 4, respectively, showing significant differences (p < 0.05, LSD). These results indicated that the residual distribution of picarbutrazox sprayed by using a multicopter on the Chinese cabbages was not uniform. However, the residues were less than the maximum residue limit in all plots. Accordingly, picarbutrazox was considered to have a low risk to human health if it was sprayed on cabbage according to the recommended spraying conditions.

Residues and Safety Evaluation of Etoxazole, Bifenazate and Its Metabolite Bifenazate-diazene in Citrus Under Open-Field Conditions

The residues of bifenazate (sum of bifenazate and bifenazate-diazene) and etoxazole in whole citrus and pulp collected from twelve regions of China were monitored and their chronic dietary risk to consumer were also evaluated. The citrus samples were extracted by a QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, and analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The average recoveries of target compounds were ranged from 83 to 100% with relative standard deviations (RSDs) of 0.59-11.8%. The limits of quantification (LOQs) for three analytes were 0.01 mg/kg. At the interval to harvest of 20 and 30 days, the residues of total bifenazate and etoxazole were from below 0.02 to 0.26 mg/kg and from below 0.01 to 0.30 mg/kg in citrus samples. The chronic risk quotients (RQs) were below 100%, indicating no unacceptable risk to consumers.

Dissipation kinetics and risk assessment of iprovalicarb + propineb fungicide in tomato under different agroclimates

Multi-location supervised field trials in India were conducted with a combination pesticide formulation (iprovalicarb 5.5% + propineb 61.25%, 66.75% WP) in tomato to study dissipation behavior at single (iprovalicarb 137.5 g a.i. ha^-1 + propineb 1531.25 g a.i. ha^-1) and double (iprovalicarb 275 g a.i. ha^-1 + propineb 3062.5 g a.i. ha^-1) dose. The samples were processed using a modified QuEChERS method for iprovalicarb and acid hydrolysis followed by carbon disulfide estimation for propineb and confirmation of their respective residues by LC-MS/MS and GC-MS. Both the fungicides in tomato fruits obey first-order kinetics irrespective of location and doses. Half-life (t_1/2) values at all the four locations ranged from 1.08 to 4.67 days for iprovalicarb and 3.36 to 11.41 days for propineb in tomato. The Food Safety and Standards Authority of India (FSSAI) has set MRL of 1 mg kg^-1 for propineb, but no MRL is yet fixed for iprovalicarb. Using OECD MRL calculator, the calculated MRL for iprovalicarb and propineb was found to be 2 and 4 mg kg^-1, respectively. The hazard quotient (HQ) < 1, theoretical maximum daily intake (TMDI) < acceptable daily intake (ADI), TMDI < maximum permissible intake (MPI), percent acute hazard index (% aHI) ≤ 1, and percent chronic hazard index (% cHI) < 1 for both the fungicides indicated that the combination formulation will not pose any dietary risk and thus considered safe for human health.

Persistence, dissipation behavior and dietary risk assessment of a combi-product of chlorantraniliprole and λ-cyhalothrin in/on pigeonpea (Cajanus cajan L.)

Pigeonpea (Cajanus cajan L.) is an annually cultivated food and forage crop, attacked by a large number of pests mainly pod borer (Helicoverpa armigera). For the control of this insect pest, a combination of broad-spectrum insecticides viz., chlorantraniliprole and λ-cyhalothrin have been in use to reduce the pod damage and increase crop production worldwide. Therefore, a field trial was conducted to study dissipation and persistence behavior of insecticides combination (Chlorantraniliprole 9.26 % + λ-cyhalothrin 4.63 % ZC) in/on pigeonpea at the recommended dose (RD) 30 g a.i./ha and double recommended dose 60 g a.i./ha (2RD). The quantitative analysis was performed using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for chlorantraniliprole and Gas chromatography with electron captured detector (GC-ECD) for λ-cyhalothrin. The Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method was validated for its accuracy, precision and sensitivity. The chlorantraniliprole persisted upto 30 days and λ-cyhalothrin persisted upto 10 days at RD and 20 days at 2RD. The half-lives (DT₅₀) of chlorantraniliprole and λ-cyhalothrin were from 4.95 to 5.78 days and 2.48–4.33 days at recommended and double recommended dose in pigeonpea, respectively. However, residues of both insecticides measured from soil at 30^th day and harvest time were below the limit of quantification (LOQ). The waiting period deciphered for chlorantraniliprole and λ-cyhalothrin applied as combi-product was 9 days at recommended dose. Dietary risk assessment (Risk quotient<1) was performed on the basis of field trial suggested the application of chlorantraniliprole and λ-cyhalothrin as combi-product at recommended dose is safe for the consumers.