Cypermethrin Residues Research Articles

Probabilistic acute dietary exposure assessment of the Chinese population to cypermethrin residues

A probabilistic estimation of dietary exposure to cypermethrin residues for the Chinese population was performed. Cypermethrin residue data were obtained from the national food contamination monitoring program for 2001–2006, encompassing 14,096 samples from 36 commodities with a detection rate of 10.4%. Food consumption data were gathered from the national nutrition and health survey conducted in 2002, comprising 65,915 consumers aged 2–100 years and 3701 children of 2–6 years old. The whole country was roughly divided into six regions and the ranges of the median and of P99.9 exposure estimated for these regions were 0.018–0.026 and 3.131–7.095 µg kg−1 bw day−1, respectively. Pak-choi and Chinese cabbage contributed 33.9 and 13.2%, respectively, to the cypermethrin intake for the general population, while pak-choi and citrus covered 30.7 and 22.5% of the total intake for children, respectively. The exposure of the rural population was higher than urban populations. Rural areas mainly located in the plains of central China had among the highest exposure of the six regions, accounting for 17.7% of the ARfD at P99.9, while the 99.99th percentile of exposure for children, especially rural children, far exceeded the ARfD, which is a cause for concern.

농약 및 동물용의약품으로 사용되는 약제의 잔류허용기준 설정 개선 - 축산물 중 cypermethrin의 잔류 사례

BACKGROUND: Cypermethrins, possess eight isomers, used both as pesticide and as veterinary drug, were set different MRLs for livestock by CCPR and CCRVDF of Codex Alimentarius. Korea Food Code designates MRLs for livestock only as pesticide. METHODS AND RESULTS: This study presented necessaries of harmonization of MRL setting for compounds used both as pesticides and as veterinary drugs with regulatory aspects, showing an example of cypermethrin residue in livestock. CONCLUSION(S): For harmonization, following factors must be considered and recommended; designation of marker residue; alpha-cypermethrin, zeta- cypermethrin, and cypermethrin, clarification of the definition of target tissues; meat, fat, muscle, by-product, eggs, milk, and etc., method of analysis; clarification of target analytes of isomers, quantitation and calculation method as a principle of residue analysis.

Determination of Cypermethrin Residues in Crucian Carp Tissues by MSPD/GC-ECD

A sensitive matrix solid-phase dispersion (MSPD)/gas chromatography-electron capture detector (GC-ECD) method was developed to determine cypermethrin residues in three tissues (muscle, liver, and gill) of crucian carp. Cypermethrin was simultaneously extracted by MSPD and determined by GC-ECD. The main parameters affecting extraction yield and selectivity, such as the type of solid adsorbent material, choice of elution solvents and their volume, were investigated to obtain interference-free extracts and quantitative cypermethrin recovery. Fortified recoveries in muscle, liver, and gill samples ranged from 84.9% to 106.1%, and relative standard deviations were <8% with fortification levels of 0.05–1 mg kg−1. Detection limits were 1.4–2.1 μg kg−1, and quantitation limits were 5.8–7.8 μg kg−1. The proposed method was successfully applied to determination of cypermethrin in fish tissue samples.

Effectiveness of Selected Reaction Monitoring for rapid assay of Cypermethrin Residue in Perilla Leaves

Many kinds of pesticides have been developed and used to yield a good harvest but the residues in agricul-tural products cause health problems. It is important to keep watch on these residues by using adequate methods of analysis. Pretreatment such as gel permeation chromatography (GPC) or column chromatography is often needed for the quantitative analysis of pesticide in agricultural products by conventional methods such as gas chromatography/low resolving power mass spectrometry (GC/LRMS). However, these pretreat-ments need a lot of work and take time. New methods saving the necessity of these pretreatments have been desired. We have applied selected reaction monitoring (SRM) to quantitatively determine cypermethrin residues in Perilla frutescens samples and compared the results with LRMS and HRMS in SIM mode. A background peak caused by the matrix overlapped the cypermethrin peak in the analysis using LRMS. SRM and HRMS in SIM mode provided chromatograms without matrix interference. The high selectivity of the product ion (m/z 127) produced from precursor ion (m/z 163) isolated the target peaks from the matrix peaks when using SRM. This method eliminates the pretreatment step, thus saving time and simplify ing the ana-lytical process.

Plastic films for polytunnels can prolong the effective residual life of cypermethrin to over 6 months

SummarySynthetic pyrethroid insecticides are degraded almost entirely by ultraviolet (UV)-catalysed oxidation. A bioassay using the beetle Tribolium confusum duVal caged on bandages soaked in 0.04% a.i. cypermethrin showed large differences in residual insecticide-life under three plastic films available for cladding polytunnels. Cypermethrin exposed to a UV film that transmitted 70% of UVB and 80% of UVA killed all beetles for 8 weeks, compared to only 3 weeks for cypermethrin exposed in a clear plastic envelope. Cypermethrin under a UV-absorbing film that reduced the transmission of UVB and UVA to 14% and 50%, respectively, gave a complete kill for 17 weeks. Reducing the transmission of UVB to virtually zero, and that of UVA to only 3%, using a UV-opaque film prolonged the effective life of the cypermethrin residue to 26 weeks, and some beetles were still killed for a further 11 weeks. Even after this time, beetles exposed to cypermethrin from the UV-opaque treatment were still affected by the insecticide, and only showed near-normal mobility after 24 months of pesticide exposure to the UV-opaque film. These results have implications for the recommended intervals between cypermethrin treatment and crop harvest, and on the time of introduction of insect-based biological control agents, when UV-opaque films are used in commercial horticulture.

Multi-residue determination of pesticides in the meat of cattle in Faisalabad-Pakistan

The aim of study was to determine the contamination in the meat and organs of cattle reared in pesticide spraying areas of Faisalabad, Pakistan. Because no such published information is available in this region. The meat and organs such as liver, lung and kidney were collected from villages situated within the radius of 25-35 Km on four different localities (Pensara, Aminpur, Jaranwala, and Sheikhupura roads) in the Northeast and Southwest of city during winter and spring seasons of 2009. Five pesticides (cyhalothrin, endosulfan, chlorpyrifos, cypermethrin and methyl parathion) were analyzed in the collected meat and organs (n=600) with solid phase microextraction and high performance liquid chromatography techniques. The residue analysis revealed that about 13, 21, 4, and 2 % muscle samples were contaminated with chlorpyrifos, cyhalothrin, cypermethrin and endosulfan, respectively. The concentration (ppm) of Chlorpyrifos (0.373 ± 0.001 vs. 0.297 ± 0.006), cypermethrin (2.962 ± 0.003 vs. 1.789 ± 0.228), endosulfan (12.938 ±0.007 vs. 14.487 ± 4.497) and cyhalothrin residues (4.521 ± 1.143 vs. 4.790 ± 0.933) were non-significantly different (p>0.05) in north east and southwest direction, respectively. Similarly, the levels of these pesticides were non significantly different in spring and winter seasons. Parathion-methyl was not detected in muscle samples. The same trend of pesticide contamination was observed in the kidney samples. Three pesticides (chlorpyrifos, cyhalothrin, cypermethrin were detected in liver and lung samples while endosulfan and parathion methyl were only detected in traces. Pesticides residues in muscle and organs were found higher than the Maximum Residual Limit (MRL) established by the international health regulatory agencies. Comparative results have indicated that chlorpyrifos, lambda-cyhalothrin, cypermethrin and endosulfan residues in muscles were about 34 times, 23 times, 47 times, and 27 times, respectively, higher than the MRL. These findings alarm a threat to the public health and suggest the need to create awareness in dairy farmers regarding the avoidance of pesticide residues in meat. (This work was supported by the Higher Education Commission, Islamabad, Pakistan.)

Dissipation of cypermethrin, chlorpyriphos, and profenofos in tomato fruits and soil following application of pre-mix formulations

Persistence of cypermethrin, chlorpyriphos, and profenofos in tomato and soil were studied following application of two pre-mix formulations of insecticides viz. Roket 44EC (profenofos 40% + cypermethrin 5%) and Action-505EC (chlorpyriphos 50% + cypermethrin 5%) at recommended (0.8-1.0 L ha(-1)) and double dosage (1.6-2.0 L ha(-1)). In all the treatments residues persisted beyond 7 days in tomato fruits. Half-life values were calculated from first-order dissipation kinetics. In the case of Roket 44EC, residues of cypermethrin on fruits dissipated with half-life of 2.0-3.6 days, whereas residues of profenophos dissipated with the half-life of 2.2-5.4 days. In the case of Action-505EC, residues of chlorpyriphos and cypermethrin dissipated from fruits with the half-life values of 2.9-3.3 and 2.5-4.8 days, respectively. In soil, residues of profenofos persisted for 7-15 days, whereas residues of chlorpyrophos and cypermethrin persisted for 0-7 days only.

Optimization of two-dimensional gas chromatography time-of-flight mass spectrometry for separation and estimation of the residues of 160 pesticides and 25 persistent organic pollutants in grape and wine

Two-dimensional gas chromatography (GC × GC) coupled with time-of-flight mass spectrometric (TOFMS) method was optimized for simultaneous analysis of 160 pesticides, 12 dioxin-like polychlorinated biphenyls (PCBs), 12 polyaromatic hydrocarbons (PAHs) and bisphenol A in grape and wine. GC × GC–TOFMS could separate all the 185 analytes within 38 min with >85% NIST library-based mass spectral confirmations. The matrix effect quantified as the ratio of the slope of matrix-matched to solvent calibrations was within 0.5–1.5 for most analytes. LOQ of most of the analytes was ≤10 μg/L with nine exceptions having LOQs of 12.5–25 μg/L. Recoveries ranged between 70 and 120% with <20% expanded uncertainties for 151 and 148 compounds in grape and wine, respectively, with intra-laboratory Horwitz ratio <0.2 for all analytes. The method was evaluated in the incurred grape samples where residues of cypermethrin, permethrin, chlorpyriphos, metalaxyl and etophenprox were detected at below MRL.

Determination of enantiomeric fractions of cypermethrin and cis‐bifenthrin in Chinese teas by GC/ECD

The pyrethroids cypermethrin and cis-bifenthrin are the major pesticides used in tea plantations in China. Potential neurotoxic, genotoxic and immunotoxic effects of chronic exposure to pyrethroids have been reported. All synthetic pyrethroids are chiral compounds. There is a need to investigate the chiral transformation among isomers after tea processing in order to obtain an accurate risk assessment of these compounds. The enantiomeric fraction (EF) of cis-bifenthrin residues was close to 0.5 in all tea samples tested, showing that the levels of (+)-isomer and (-)-isomer were equivalent and there was no preferential degradation. However, the patterns of EFs of cypermethrin residues varied depending on the type of tea. The EF of isomer 1R-3R-alphaS increased in black and dark tea samples (EF = 0.200-0.343) compared with the reference cypermethrin commercial mixture (EF = 0.116). In one oolong tea sample it was found that the relative abundance of some isomers was preferentially enhanced: 1R-3R-alphaS (EF = 0.260), 1S-3S-alphaR (EF = 0.263) and 1R-3S-alphaS/1S-3R-alphaR (the last elution peak, EF = 0.275). The relationship between EF and compound concentration was also analysed, showing that the variation in EFs of cypermethrin was concentration-dependent. These findings appear to be useful for assessing the species-specific risk of exposure to cypermethrin and cis-bifenthrin.

Effect of Processing on Dislodging of Cypermethrin Residues on Brinjal

Brinjal fruits were sprayed with recommended dose (0.001%) of cypermethrin. Effects of processing viz. washing, cooking in water, cooking in oil, microwave cooking, and grilling was studied to dislodge cypermethrin residues on brinjal. Cypermethrin residues remaining in the control and processed samples were analyzed by gas chromatography equipped with ECD. Dislodging of cypermethrin residues was observed more in grilling (50.12%), followed by cooking in oil (45.2%), cooking in water (41.4%), and microwave cooking (40.89%) after 1st day of the treatment. Reduction of residues after washing treatment was minimal.

Determination of Pesticide Residues in Integrated Pest Management and Nonintegrated Pest Management Samples of Apple (Malus pumilaMill.)

Studies were undertaken to analyze the residues of commonly used pesticides viz. chlorpyrifos, endosulfan, dicofol, cypermethrin, fenvalerate, propargite, malathion, phorate, carbendazim, carbosulfan, thiamethoxam, and mancozeb in apple of integrated pest management (IPM) and non-IPM samples collected from the IPM and non-IPM fields of Shimla. We also present a method for the determination of these pesticides in apple samples. Residues of chlorpyrifos, endosulfan, dicofol, cypermethrin, fenvalerate, and propargite were analyzed by gas chromatography, while residues of carbendazim, carbosulfan, and thiamethoxam were analyzed by high-performance liquid chromatography. Residues of mancozeb were determined by a colorimetric method. Recoveries of all of the pesticides ranged from 61.30 to 95.46% at 0.1, 0.2, and 1.0 microg g(-1) levels of fortification with relative standard deviations ranging between 0.8 and 8.7. Apples from IPM and non-IPM orchards were analyzed for these pesticides using a developed method. Except for carbendazim and chlorpyrifos, the residues of all of the pesticides analyzed were below detectable limits. Although residues of carbendazim and chlorpyrifos were below the prescribed limits of maximum residue levels in both IPM and non-IPM orchards, residues were lower in apples from IPM orchards.

Determination of cypermethrin in palm oil matrices

AbstractIn this study, a new method was developed for the determination of cypermethrin residue in both crude palm oil (CPO) and crude palm kernel oil (CPKO) using GC with electron capture detector. In this method, the oil was extracted with acetonitrile. Aliquots were cleaned‐up using combined solid phase extraction (SPE), and a primary‐secondary amine in combination with graphitized carbon black. The SPE cartridges were first conditioned and then eluted with acetonitrile. Cypermethrin recoveries from the fortified CPO samples were 87–98% with relative standard deviation (RSD) values of 4–8%, while those for the fortified CPKO samples were 83–100% with RSD values of 3–10%. Since good recoveries were obtained with RSD values below 10% in most cases, the proposed methodology will be useful for the analyses of palm oil samples. The method was successfully applied to the analysis of cypermethrin in real palm oil samples from various parts of Malaysia. No cypermethrin residue was found among 30 samples analyzed.

Análise de resíduos de agrotóxicos em tomates empregando dispersão da matriz em fase sólida (DMFS) e cromatografia gasosa

This work was aimed on optimization of the matrix solid-phase dispersion (MSPD) technique using gas chromatography for analyzing residues of chlorpyriphos, λ-cyhalothrin, cypermethrin and deltamethrin in tomatoes. The results showed that silica was more efficient for the clean up of extracts, but florisil provided the highest recovery rates. A 23 complete factorial design was carried out to evaluate the absorbent/sample ratio, presence of co-column (silica) and ultrasonic bath on the extraction rate. The percentage of extraction of the pesticides chlorpyriphos, λ-cyhalothrin, cypermethrin and deltamethrin were 64.7, 88.3, 99.2 and 89.2%, respectively, with relative standard deviations below 5%.

Persistence of Acephate and Cypermethrin on Cotton Leaves, Cottonseed, Lint and Soil

Following foliar applications of combination formulation (cypermethrin 5% + acephate 45% DF) at 850 and 1,700 g ha(-1), resulting in active application of acephate at 382.5 and 765 g a.i. ha(-1) whereas active application of cypermethrin at 42.5 and 85 g a.i. ha(-1), the average initial deposits of acephate on cotton leaves were found to be 13.45 and 27.73 mg kg(-1), at single and double the doses of application, respectively. Residues of acephate declined below detectable level of 0.02 mg kg(-1) after 15 days of applications at application rates with t ((1/2)) values of 1.56 and 0.68 days, respectively. Similarly, the average initial deposits of cypermethrin were found to be 22.31 and 32.45 mg kg(-1), respectively. Cypermethrin residues reached below its detectable level of 0.02 mg kg(-1) after 21 days of its application at both the dosages of application. The half-life values for cypermethrin were observed to be 0.71 and 0.69 days, corresponding to single and double the dose of application, respectively. Interestingly, none of the samples of cottonseed, lint and soil showed presence of acephate or cypermethrin at the detection limit of 0.02 mg kg(-1) at first pick of the harvest time of the crop.

Photolysis of thin films of cypermethrin using in situ FTIR monitoring: Products, rates and quantum yields

Cypermethrin is a synthetic pyrethroid insecticide commonly used both indoors and outdoors. Following its application, cypermethrin residues are exposed to atmospheric oxidants, such as ozone and OH radicals, as well as to solar radiation. The current work focuses on the photochemical degradation of cypermethrin under 254 nm, 310 nm, and solar radiation; including kinetic analysis, quantum yields, and identification of volatile and non-volatile products. The investigation was done using a combined FTIR set-up for parallel analysis of condensed and gas phases. Complementary GC–MS analysis was conducted on the pesticide’s residues. Quantum yields of 0.41 and 0.25 were obtained under 254 and 310 nm, respectively. These values are in agreement with outdoor studies and are higher than the known yields for aqueous solution. The values obtained under all tested conditions suggest that photodegradation of adsorbed cypermethrin is a major outdoor degradation pathway. Oxygen presence was found to increase degradation rate and quantum yield. The identified photoproducts include 3-phenoxybenzaldehyde, 3-phenoxybenzoic acid, acetonitrile ( m-phenoxyphenyl), and cypermethrin isomers on the surface and formic acid, CO 2 and CO in the gas phase. The condensed phase products are more polar than the parent molecule, suggesting that they may be susceptible to a greater leaching rate in soils.

Analysis of insecticides in okra and brinjal from IPM and non-IPM fields

Samples of okra and brinjal fruits, collected from non-integrated pest management (Non-IPM) and IPM fields in village Raispur, Ghaziabad District (U.P.), were analyzed for pesticide residues. The residues of chlorpyrifos in soil were 4.219 and 1.135 microg/g at harvest time in non-IPM and IPM fields of summer okra crop from initial value of 0.407 microg/g before sowing, while in brinjal crop, it was not detected in soils of any trials. During first year of study, the residues of chlorpyrifos and cypermethrin in okra fruit were observed to be 5.75 and 0.625 microg/g, respectively, for non-IPM fields; and 0.104 microg/g of chlorpyrifos for IPM trials. The pesticide residues were found to be 0.77, 1.39, 0.4 and 0.32 microg/g for cypermethrin, chlorpyrifos, monocrotophos and dimethoate, respectively, for non-IPM okra fruits in second year. For brinjal fruit, residues of cypermethrin and imidacloprid were not detected in IPM trials while it was found to be 0.28 and 0.78 microg/g for cypermethrin and chlorpyrifos respectively, for non-IPM trials.

Pesticide residues in beeswax samples collected from honey bee colonies (Apis mellifera L.) in France

In 2002 a field survey was initiated in French apiaries in order to monitor the health of honey bee colonies (Apis mellifera L.). Studied apiaries were evenly distributed across five sites located in continental France. Beeswax samples were collected once a year over 2 years from a total of 125 honey bee colonies. Multiresidue analyses were performed on these samples in order to identify residues of 16 insecticides and acaricides and two fungicides. Residues of 14 of the searched-for compounds were found in samples. Tau-fluvalinate, coumaphos and endosulfan residues were the most frequently occurring residues (61.9, 52.2 and 23.4% of samples respectively). Coumaphos was found in the highest average quantities (792.6 microg kg(-1)). Residues of cypermethrin, lindane and deltamethrin were found in 21.9, 4.3 and 2.4% of samples respectively. Statistical tests showed no difference between years of sampling, with the exception of the frequency of pyrethroid residues. Beeswax contamination was the result of both in-hive acaricide treatments and, to a much lesser extent, environmental pollution.

Status of insecticide contamination of soil and water in Haryana, India

Twelve samples each of soil and ground water were collected from paddy-wheat, paddy-cotton, sugarcane fields and tube wells from same or near by fields around Hisar, Haryana, India during 2002-2003 to monitor pesticide residues. Residues were estimated by GC-ECD and GC-NPD systems equipped with capillary columns for organochlorine, synthetic pyrethroid and organophosphate insecticides. In soil, HCH (0.002-0.051 microg g(-1)), DDT (0.001-0.066 microg g(-1)), endosulfan (0.002-0.039 microg g(-1)) and chlordane (0.0002-0.019 microg g(-1)) among organochlorines, cypermethrin (0.001-0.035 microg g(-1)) and fenvalerate (0.001-0.022 microg g(-1)) among synthetic pyrethroids and chlorpyriphos (0.002-0.172 microg g(-1)), malathion (0.002-0.008 microg g(-1)), quinalphos (0.001-0.010 microg g(-1)) among organophosphates were detected. Dominant contaminants were DDT, cypermethrin and chlorpyriphos from the respective groups. In water samples, HCH, DDT, endosulfan and cypermethrin residues were observed frequently. Only chlorpyriphos among organophosphates was detected in 10 samples. On consideration of tube well water for drinking purpose, about 80% samples were found to contain residues above the regulatory limits.

Pesticide Utilization and Insecticide Residue Levels in Rice from Banaybanay, Davao Oriental

Pesticides for rice production were widely used in Banaybanay, Davao Oriental. These included insecticides, herbicide and molluscide in this order. etofenprox and fipronid were the most utilized insecticide, butachlor and thiobencarb+24D for herbicide. copper oxychloride and benomyl were the most used fungicides by farmers while niclosanide for mulluscide. Farmers used the conventional knapsack sprayer in applying pesticides in the rice field. Farmers usually applied insecticide at a range of one to more than 11 times but most applied it from one to five times. Herbicides and fungicides were applied once or twice per season although few had to apply five times Farmers' frequency of spraying and dosage of applying pesticides were usually based on the recommendation indicated on the product label. Only a few did not follow the manufacturer's instructions. Insecticide and herbicide were applied at a range of one to IOL; one to six L. of fungicide or molusscide; others had used one to 10 sachsets, and five to 50 sacks of fertilizer per cropping season. Twenty-two percent had been using pesticides for six to 10 years, and 4% for more than 31 years. Insesticide residues were detected in Hybrid rice. Cypermethrin residue was detected above the level of Allowable Daily Intake while deltamethrin was below it.

Toxicity to honeybees of water guttation and dew collected from winter rape treated with Nurelle D&lt;sup&gt;®&lt;/sup&gt;

The acute and chronic toxicity to honeybees, &lt;i&gt;Apis mellifera&lt;/i&gt; of water guttation and dew collected from winter rape plants treated with the insecticide Nurelle D&lt;sup&gt;®&lt;/sup&gt; (a.i. chlorpyriphos + cypermethrin) was investigated. Caged bees were fed on sugar syrup containing water guttation and dew for 24 h (acute toxicity test) and for 10 days (chronic toxicity test). Bee mortality and food consumption were determined daily. A contact toxicity test was performed within 24 h on bees kept in Petri dishes (10 bees per dish) lined with filter paper saturated with the test solution. The acute Nurelle D&lt;sup&gt;®&lt;/sup&gt; contact and oral toxicity tests showed that the mortality of bees treated with water guttation and dew collected from the treated plants did not exceed 10%. A chronic toxicity test showed that adding contaminated water guttation and dew to the syrup caused an insignificant increase in bee mortality and reduced the syrup consumption significantly. The chlorpyriphos residue found in contaminated water guttation and dew were below the limit of detection (0.8 µg/kg) and the cypermethrin residue was below the detection levels.