Development and validation of QuEChERS method for estimation of chlorantraniliprole residue in vegetables

Residue dissipation dynamics and dietary risk assessment of emamectin benzoate, chlorantraniliprole, chlorfenapyr, and lufenuron in cabbage

Emamectin benzoate (EB), chlorantraniliprole (CTP), chlorfenapyr (CFP), and lufenuron (LFR) are widely used to control Spodoptera exigua on cabbage. This study is aimed at establishing a universal, sensitive, accurate, and efficient method for the determination of these pesticide residues in cabbage using QuEChERS pretreatment combined with ultra-performance liquid chromatography or gas chromatography-tandem mass spectrometry (UPLC‒MS/MS or GC‒MS/MS). The recoveries of these pesticides (containing metabolites) in cabbage detected by the optimized method ranged between 80.9% and 99.9%, with relative standard deviations (RSDs) of 0.164-12.5%. The limit of quantification (LOQ) of the four pesticides was determined to be 0.01 mg/kg. The standard curve, accuracy, precision, and LOQ of the analysis method all met the requirements of pesticide residue detection. The optimized method was used to detect the dissipation dynamics and terminal residues in 12 regions. The dissipation half-lives of CTP, CFP, and LFR were 3.35-7.01 d, 2.29-4.75 d, and 3.24-6.80 d, respectively. The terminal residues of all these pesticides were below the maximum residue limits (MRLs). The dietary risk assessment indicated that the dietary risk probabilities for EB, CTP, CFP, and LFR were all less than 1 and were within the acceptable range. This study provides a comprehensive assessment of the residues and dietary risks of EB, CTP, CFP, and LFR for the scientific use of pesticides.

Uncovering the Dissipation of Chlorantraniliprole in Tomatoes: Identifying Transformation Products (TPs) and Coformulants in Greenhouse and Laboratory Studies by UHPLC-Q-Orbitrap-MS and GC-Q-Orbitrap-MS

The present study addressed the dissipation of the insecticide chlorantraniliprole in tomatoes treated with Altacor 35 WG under laboratory and greenhouse conditions, as well as the identification of transformation products (TPs) and coformulants, performing suspect screening analysis. Analyses were performed by ultra-high-performance liquid and gas chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap-MS and GC-Q-Orbitrap-MS). In all cases, chlorantraniliprole was fitted to a biphasic kinetic model, with R² values greater than 0.99. Dissipation was noticeably faster in greenhouse studies, in which even 96% dissipation was achieved over 53 days. One TP, IN-F6L99, was tentatively identified in both greenhouse and laboratory studies and was semiquantified by using chlorantraniliprole as the analytical standard, yielding a top value of 354 μg/kg for laboratory studies, whereas values for greenhouse studies fell under the limit of quantitation (LOQ). Finally, a total of 15 volatile coformulants were identified by GC-Q-Orbitrap-MS.

Chlorantraniliprole in foods: Determination, dissipation and decontamination

Chlorantraniliprole (CAP) is the first commercially available anthranilic diamide insecticide that targets ryanodine receptors. However, excessive use of CAP can lead to persistent contamination on treated foods and adverse effects on human wellness. The current review focuses on CAP residue analysis in foods by using chromatographic techniques. QuEChERS (quick, easy, cheap, effective, rugged and safe) is the most widely used sample preparation strategy and liquid chromatography tandem mass spectrometry is the predominant analytical method for various food matrices including vegetable, fruit, grain, fish and so on. Moreover, this review summarizes the dissipation pattern of CAP on foods and found it usually dissipates fast on plant in open-field environment. For decontamination, common culinary cleaning methods could effectively remove CAP from vegetables. Finally, some new directions are proposed for better advancement.

Development and validation of a modified QuEChERS method coupled with LC-MS/MS for simultaneous determination of difenoconazole, dimethoate, pymetrozine, and chlorantraniliprole in brinjal collected from fields and markets places to assess human health risk

An effective and sensitive analytical method was developed to quantify the most common pesticide residues (difenoconazole, dimethoate, pymetrozine, and chlorantraniliprole) used for brinjal cultivation in Bangladesh. The quantification of the analytes was done using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted using a modified QuEChERS method and followed by purification with dispersive solid phase extraction (d-SPE) sorbents (PSA, GCB, and C18). Matrix-matched calibration with a regression coefficient R² ≥ 0.9964 were used to minimize the brinjal matrix effect. The method was validated in quintuple (n = 5) at five different spiked levels (8-400 μg/kg) having recoveries in the range of 70.3-113.2% with relative standard deviations RSDs ≤6.8%, limits of detection (LOD) and limits of quantification (LOQ) was in the range of 0.15-0.66 μg/kg and 0.4-2.0 μg/kg, respectively, for the four analytes. A total 100 samples (50 samples directly from fields of Jessore district, Bangladesh and 50 samples from local market of Dhaka, Bangladesh) were collected to analyse the pesticides residue. The result showed that pesticides residue was found in both the field and market collected samples, 54% and 38%, respectively. The overall mean residue levels of four pesticides in field samples were significantly higher than those of market samples. Moreover, 20% of the field samples and 10% of the market samples had dimethoate residues, which were the most abundant among the four analytes and it ranged from 0.017 to 0.252 mg/kg. In terms of health risk assessments, dimethoate showed the highest estimated daily intake (EDI) and hazard quotient (HQ) values that are 3.02 × 10^-5 mg/kg/day and 1.51%, respectively, in field samples. Till now, there have been no regulations or guidelines for the maximum admissible pesticide residue in Bangladesh. Therefore, the above findings will be an initial step for the regulatory authorities of Bangladesh to implement regulations and guidelines for pesticide usage.

Dissipation behavior, residue transfer, and safety evaluation of chlorantraniliprole and indoxacarb during tea growing and brewing by ultrahigh-performance liquid chromatography-tandem mass spectrometry

A reliable and simple analytical method was developed and validated to simultaneously determine chlorantraniliprole and indoxacarb in tea using ultrahigh-performance liquid chromatography-tandem mass spectrometry. The average recoveries of chlorantraniliprole were in the range of 86-110%, with the precision of intraday (n = 5) and interday (n = 15) ranging from 1.9 to 8.4% and from 2.4 to 8.8%, respectively. The average recoveries of indoxacarb were in the range 81-105%, with the precision of intraday (n = 5) and interday (n = 15) ranging from 2.0 to 9.8% and from 2.7 to 9.1%, respectively. The limits of quantification (LOQs) were all 0.01 mg/kg. The results based on the supervised field trials showed that chlorantraniliprole and indoxacarb in two tea samples followed first-order kinetics models with half-lives of 2.2-4.7 days and 2.5-3.5 days, which could be regarded as a moderately degrading pesticide. The terminal residues of chlorantraniliprole and indoxacarb in made tea were below 6.7 and 4.5 mg/kg, respectively, lower than their corresponding maximum residue limits (MRLs) established by several major countries and organizations (50 and 5 mg/kg). The leaching rates of chlorantraniliprole and indoxacarb during the tea brewing ranged from 4.78 to 12.62% and 4.13 to 10.67%, respectively. The chronic intake risk quotient (RQc) values for chlorantraniliprole and indoxacarb were 0.24% and 35.10%, while the acute dietary risk assessment (RQa) value of indoxacarb was 5.8%, which were all much lower than 100%. The results in the present study indicated that the health risk posed by the chlorantraniliprole and indoxacarb mixture pesticides was negligible in tea for consumers at the recommended dosages.

Residue and Risk Assessment of Imidacloprid and Chlorantraniliprole in Open Field and Greenhouse Celery

ABSTRACT

The residue levels and risk assessment of imidacloprid (IMI) and chlorantraniliprole (CAP) in celery grown under open field and greenhouse cultivation were investigated. Both pesticides were used through foliar application and soil drench application at the recommended dose (RD) and 10-fold recommended dose (10RD). The half-lives of IMI and CAP in celery were 1.9 to 5.8 days and 4.3 to 6.5 days after foliar application, respectively, and the dietary risk quotients of IMI and CAP were 14.8 to 18.3% and 1.0 to 1.2%, respectively. For soil drench application, the half-lives of IMI and CAP in soil were 17.5 to 28.5 days and 15.1 to 23.7 days, respectively. Celery plants were able to absorb both insecticides from the soil. The highest concentrations of IMI in celery plants were 0.12 to 0.24 mg kg-1 (RD) and 0.34 to 0.39 mg kg-1 (10RD), and those for CAP were 0.0081 to 0.015 mg kg-1 (RD) and 0.028 to 0.057 mg kg-1 (10RD). Based on the highest residues of IMI and CAP in celery, the dietary risk quotients of IMI and CAP were 15.0% (RD) to 15.6% (10RD) and 1.0% (RD and 10RD) after soil drench application, respectively. The observed bioconcentration factors were 1.38 to 2.11 (IMI) and 0.35 to 0.48 (CAP), indicating that celery accumulated IMI more easily than CAP. The foliar and soil applications of IMI and CAP in celery at the RD and 10RD do not pose a safety risk to consumers.

HIGHLIGHTS

Development of a nanobody-based ELISA for the detection of the insecticides cyantraniliprole and chlorantraniliprole in soil and the vegetable bok choy

Cyantraniliprole and chlorantraniliprole are anthranilic diamide insecticides acting on ryanodine receptors. In this study, two camel-derived nanobodies (Nbs, named C1 and C2) recognizing cyantraniliprole as well as chlorantraniliprole were generated. C1-based enzyme-linked immunosorbent assays (ELISAs) for the detection of the two insecticides were developed. The half-maximum signal inhibition concentrations (IC₅₀) of cyantraniliprole and chlorantraniliprole by ELISA were 1.2 and 1.5 ng mL^-1, respectively. This assay was employed to detect these two insecticides in soil and vegetables. The average recoveries of cyantraniliprole from both bok choy (Brassica chinensis L.) and soil samples were 90-129%, while those of chlorantraniliprole were in a range of 89-120%. The insecticide residues in soil and bok choy, which were collected from plots sprayed with cyantraniliprole and chlorantraniliprole, were simultaneously detected by the resulting ELISA and a high-performance liquid chromatography (HPLC) method, showing a satisfactory correlation. Higher concentrations of chlorantraniliprole than cyantraniliprole were detected in soil and vegetables, which indicates the longer persistence of chlorantraniliprole in the environment.

Long-term effects of chlorantraniliprole reduced risk insecticide applied as seed treatment on lady beetle Harmonia axyridis (Coleoptera: Coccinellidae)

Chlorantraniliprole (CAP) is a reduced risk insecticide, which used as seed treatment in many crops. However, CAP residues can contaminate pollen and nectar, becoming a potential risk to beneficial arthropods. The aims of this study were to (1) determine the non-target effects of CAP seed treatment of cotton on Harmonia axyridis (Coleoptera: Coccinellidae) over two generations, and (2) assess the ability of the lady beetles to avoid plants grown from treated seeds. The exposure of H. axyridis larvae and adults to cotton seedlings grown from CAP treated seeds did not have a significantly affect on any life history parameters of the lady beetles directly exposed (F0). However, CAP caused significant transgenerational effects in the both larval and adult stages of H. axyridis. The CAP treatment of larvae exposure reduced the larval and pupal developmental time and the male body weight of F1 generation as well as the survival of the lady beetles over the developmental stages. In the adult bioassay, CAP seed treatment reduced both pupal developmental time and egg viability of F1 generation and decreased the survival of H. axyridis over the F1 generation developmental. In olfactometer test, only the H. axyridis larvae were able to avoid cotton seedlings grown from CAP treated seeds. The results of this study confirm the hypothesis that systemic insecticides, when applied to seed treatments, can cause negative effects on non-target organisms. In addition, the study emphasizes the importance of long-term assessments of the pesticides side-effects on beneficial arthropods.

Surveillance of Chlorantraniliprole Residues in Vegetables and Fruits Using LC-MS/MS

We measured the residual amounts of chlorantraniliprole in various vegetables and fruits. Sample solutions were prepared according to our routine procedure based on the QuEChERS method and analyzed by LC-MS/MS. Performance characteristics were evaluated for 8 kinds of food samples by means of recovery tests of 5 replicates at the concentration of 10 ng/g. Recoveries and RSDs (％) ranged from 50.2 to 93.4％ and from 2.1 to 9.7％, respectively. Application of this method to survey 207 vegetables and 163 fruits gave detection rates of 8.2 and 1.2％, respectively. In vegetables, detection rates were high in okra (4 out of 10 samples), paprika (4 out of 23 samples) and tomato (2 out of 6 samples), and leaf vegetables such as lettuce, mizuna, spinach and wrinkled greens also contained high concentrations of chlorantraniliprole. The highest residual concentration was 571 ng/g in mizuna. The samples containing chlorantraniliprole seemed to be mainly from Asian countries, including samples of domestic Japanese origin. However, none of them contained more than the MRL, which suggests that the use of chlorantraniliprole has been properly controlled.

Development and validation of HPLC methods for analysis of chlorantraniliprole insecticide in technical and commercial formulations

Effective, selective, precise and accurate liquid chromatographic analytical methods for the analysis of a novel chlorantraniliprole insecticide in technical and formulation (coragen, 20% SC) have been optimized and validated. Eight methods were designed based on different mobile phases, temperature and two HPLC columns. The mobile phase consists of two mixtures (acetonitrile:water, 70:30 and methanol:water, 70:30) with 25 or 40ºC. HPLC analysis of chlorantraniliprole was carried out at a wavelength of 260 nm, with a flow rate of 0.8 mL/min. The calibration curves showed a good linear relationship (R² ˃ 0.99) in the injected quantities ranged from 0.0125 to 1.00 μg. Limit of detection (LOD) was found to be 3.94 to 14.56 ng and from 5.95 to 12.93 ng using the analytical methods I to IV by MicroPack CN-10 and V-VIII by ZORBAX Eclips Plus C18 columns, respectively, based on SDslope values. ZORBAX Eclips Plus C18 column with method VI was the best one (R² = 1.00 and RSD = 0.30), short retention time (4.936 min), high theoretical plates per column (65457.15) compared to others and LOD = 6.49 ng. The accuracy of the best method was demonstrated by recovery rates of 83.04% to 98.50% for grape samples supplemented with 5, 10 and 50 mg chlorantraniliprole/kg.

Degradation pattern and risk assessment of chlorantraniliprole on berseem (Trifolium alexandrinum L.) using high performance liquid chromatography

The persistence pattern of chlorantraniliprole on berseem leaves and its risk assessment for the safety of cattle were studied. QuEChERS method was used for the extraction and cleanup of samples and the residues of chlorantraniliprole were estimated using high performance liquid chromatography (HPLC) and confirmed by Liquid Chromatograph-Mass Spectrometer (LCMS-MS). The dissipation studies on berseem were carried out by application of chlorantraniliprole at five different dosages i.e. 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1). Average initial deposits of chlorantraniliprole were found to be 0.47, 0.61, 0.78, 1.15 and 1.31 mg kg(-1), respectively. The residues reached below determination limit (BDL) of 0.01 mg kg(-1) in 5, 7, 7, 10 and 10 days for 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1) dosages, respectively. Half-life (t1/2) of chlorantraniliprole on berseem was observed to be 0.93, 1.14, 1.06, 1.00 and 1.33 days, respectively, at 11.6, 17.1, 23.1, 34.7 and 46.2 g a.i. ha(-1). It was found that the theoretical maximum residue contributions (TMRC) values reached below maximum permissible intake (MPI) on 0 day in berseem samples treated with chlorantraniliprole. These studies, therefore suggest that the use of chlorantraniliprole formulation at different dosages does not seem to pose any hazards to the consumers and a waiting period of one day is suggested to reduce the risk before consumption of berseem leaves. These data could provide guidance for the proper and safe use of this pesticide on berseem in India.

Dietary chlorantraniliprole suppresses reproduction in worker bumblebees

BACKGROUND

Pollinators such as the bumblebee, Bombus terrestris, fulfil a crucial role in agriculture. In this context, tests were conducted with the insecticide chlorantraniliprole (Coragen®) as a model compound active on the ryanodine receptor of insects.

RESULTS

Chronic oral exposure via pollen induced lethargic behaviour in B. terrestris workers and their offspring (drones). Indeed, in nests exposed to 0.4 mg L(-1) , representing 1/100 of the concentration recommended for use in the field, workers and drones did not take their defensive position upon stimulation and they were less active than non-exposed insects. The different risk assessment tests used here demonstrated that contact and pollen exposure had no effect on bumblebee worker survival, whereas oral exposure via sugar water caused both acute (72 h LC50  = 13 mg L(-1) ) and chronic (7 week LC50  = 7 mg L(-1) ) toxicity. Severe sublethal effects on reproduction were recorded in nests orally exposed to pollen treated with chlorantraniliprole.

CONCLUSION

The present study identified an important physiological endpoint of sublethal effects on reproduction, as this is associated with lethargic behaviour after oral intake. As such, this is a factor that should now be incorporated into future risk assessments. Secondly, it confirmed that the assessment of sublethal effects on behaviour is needed for adequate risk assessment of 'potentially deleterious' compounds with a neurogenic target, as is also pointed out in the recent European Food Safety Authority (EFSA) guidelines.