Residue trial data reported by the Joint FAO/WHO Meeting on Pesticide Residues (JMPR) have been reviewed to establish whether or not the resulting residues in harvested commodities are proportional to the pesticide application rate used on the crop. Numerous sets of trials were identified where the only parameter varied was application rate or spray concentration. Analysis of this database in terms of application rate, spray concentration, formulation type, preharvest interval, crop, pesticide, residue level and application type confirms that residues scale with application rate (proportionality principle). It is anticipated that use of the proportionality principle by regulators and those interested in evaluating pesticide residue data will improve pesticide risk assessment. PMID:21452167

Two rapid methods of sample preparation and analysis of fatty foods (e.g. milk, eggs, and avocado) were evaluated and compared for a wide range of 32 pesticide residues. One method, dubbed the "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method for pesticide residue analysis, entail...

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...regulations in 40 CFR part 180 for residues of pesticide chemicals in or on...

...Several Pesticide Petitions for Residues of Pesticide Chemicals in or on Various...establishment of regulations for residues of pesticide chemicals in or on various...regulations in 40 CFR part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...regulations in 40 CFR part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

...Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...modification of regulations for residues of pesticide chemicals in or on various...CFR part 174 or part 180 for residues of pesticide chemicals in or on...

The analytical method to determine organochlorine pesticides in natural medicines included in The Japanese Pharmacopoeia (JP), 15th edition,1) is not adequate because the recovery rates of organochlorine pesticides in Glycyrrhizae radix are very low. In this study, we developed a method to analyze organochlorine pesticides in Glycyrrhizae radix with acceptable recovery rates. The method enables analysis of organochlorine pesticides in all natural medicines for which maximum residue levels are set.   

The pesticide residues in foods have received increasing attention as one of the most important food safety issues. Therefore, more strict regulations on the maximum residue limits (MRLs) for pesticides in foods have been established in many countries and health organizations, based on the sensitive and reliable analysis methods of pesticide residues. However, the analysis of pesticide residues is a continuing challenge mainly because of the small quantities of analytes as well as the large amounts of interfering substances which can be co-extracted with them, often leading to experimental errors and damage to the analytical instruments. Thus, extensive sample preparation is often required for the pesticide residue analysis for the effective extraction of the analytes and removal of the in...

In the Japanese Food Sanitation Law, the water content or loss on drying (LOD) value of standard materials for pesticide residue analysis is not officially designated. In the present study, to investigate the actual situation of the water content or LOD value of commercial pesticide standards, 40 pesticide standards were determined by the Karl-Fisher aquametry (KF) and 24 pesticide standards were done by a thermogravimetric analysis (TGA). Furthermore, the applicability of KF and TGA was also discussed. The water content or LOD values of most pesticides were within 1%, therefore they are regarded as having the negligible values within the limit of error for the residual pesticide analysis. However, since some pesticides, dichloropropionic acid sodium salt, sodium dimethyl dithiocarbamate, paraquat, diquat dibromide, formamidine hydrochloride, maneb, iminoctadine triacetate, mancozeb and monocrotophos, had relatively large amounts of water or LOD values, the water content and LOD value of such pesticides should be carefully considered during the pesticide residue analysis. For comparison of KF and TGA, there are differences in both the data for some pesticide standards. The reason seems that the pesticides interfere with the KF redox reaction.   

...pesticide chemical residue...number of analyses to determine...Relationship (SAR) analysis, no structural alerts for...physical/chemical properties...and risk analysis can be...determine which chemicals have a common...damage the structural...

A multiclass and multiresidue method for pesticide analysis in tomato was validated. Extraction and pre-concentration of the pesticide residues from acetonitrile extracts was performed by using dispersive liquid-liquid microextraction (DLLME) technique, followed by gas chromatography-mass detection. DLLME was performed using carbon tetrachloride as extractive solvent and acetonitrile extract as dispersive solvent, in order to increase enrichment factor of the extraction procedure. Validation parameters indicated the suitability of the method for routine analyses of thirty pesticides in a large number of samples. In general, pesticide recoveries ranged between 70% and 110% and repeatability ranged between 1% and 20%. The proposed method was applied to the monitoring of pesticides in tomatoe...

...Notice of Filing of a Pesticide Petition for Residues of a Aspergillus flavus...modification of regulations for residues of a pesticide chemical in or on various...in 40 CFR part 180 for residues of a pesticide chemical in or on...

...of Receipt of a Pesticide Petition Filed for Residues of Polymeric Polyhydroxy...initial filing of a pesticide petition proposing...a regulation for residues of the plant growth...a regulation for residues of the pesticide in or on all...

...Meeting of the Codex Committee on Pesticide Residues AGENCY: Office of the Under...Session of the Codex Committee on Pesticide Residues (CCPR) of the Codex Alimentarius...establishing maximum limits for pesticide residues in specific food items or...

A novel analytical approach has been developed and evaluated for the quantitative analysis of 15 organophorous pesticides residues in camellia oils. The proposed methodology is based on acetonitrile/water (3:1, V/V) extraction, followed by matrix solid-phase dispersion, using aminopropyl as dispersant material. Then gas chromatography-flame photometric detection was applied for the pesticide residue analysis. The optimal sorbent quantity was studied. The results demonstrated that the method achieved acceptable quantitative recoveries of 71.5?%?104.2?% with relative standard deviations <19?%, and the method limit of detection at or below the regulatory maximum residue limits for the pesticides were achieved.

The effects of washing, storing, boiling, peeling, coring and juicing on pesticide residue were investigated for field-sprayed Discovery and Jonagold apples. Residues of chlorpyrifos, cypermethrin, deltamethrin, diazinon, endosulfan, endosulfan sulfate, fenitrothion, fenpropathrin, iprodione, kresoxim-methyl, lambda-cyhalothrin, quinalphos, tolylfluanid and vinclozolin in the processed apples were analysed by gas chromatography. Statistical analysis showed that reductions of 18-38% were required to obtain significant effects of processing practices, depending on pesticide and apple variety. Juicing and peeling the apples significantly reduced all pesticide residues. In the case of detectable pesticide residues, 1-24% were distributed in the juice and in the peeled apple. None of the pesticide residues was significantly reduced when the apples were subject to simple washing or coring. Storing significantly reduced five of the pesticide residues: diazinon, chlorpyrifos, fenitrothion, kresoxim-methyl and tolylfluanid, by 25-69%. Residues of the metabolite endosulfan sulfate were increased by 34% during storage. Boiling significantly reduced residues of fenitrothion and tolylfluanid by 32 and 81%, respectively. Only a few of the observed effects of processing could be explained by the physical or chemical characteristics of the pesticides. No differences in effect of processing due to apple variety were identified.

The advantages and drawbacks of coupled chromatographic techniques are discussed on the basis of selected applications of LC-LC and LC-GC in the analysis of pesticide residues applied to environmental biological samples. (author). 18 refs.; 5 figs.; 2 tabs.

A method was developed for the extraction, clean-up, and analysis of multiple pesticides from cotton wipe media used in human exposure studies to collect residues from residential hard surfaces. Measurements of pesticides are critical for estimating dermal and indirect ingestion ...

The potential of Raman spectroscopy in the analysis of low concentration organic contaminants on apples' surface was evidenced in this study. Chlorpyrifos, an organophosphorus pesticide, was used as a probe for this purpose. The characteristic peaks of fingerprints of pesticide on an aluminum substrate and apple fruit cuticle without pesticide residue were acquired first. Then a concentration range of chlorpyrifos (commercial products at 40%) solutions were made using deionised and distilled water. Single 100 ?L droplets of the chlorpyrifos solutions were placed gently on apple fruit cuticles and left to dry before analysis. Through comparative analysis of the Raman spectra data collected, 341, 632 and 1237cm-1 were identified to detect the chlorpyrifos pesticide residue on apple surface. Based on the relationship between the Raman intensity of the most prominent peak at around 632cm-1 and the pesticide concentrations, the limit of detection of ordinary Raman spectrum for chlorpyrifos was estimated to be 48ppm.

...FRL-9364-3] Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...July 25, 2012, concerning Pesticide Petition (PP) 2F8026...establish tolerances for residues of the herbicide...

Intensive residential use of insecticides has resulted in their ubiquitous presence as contaminants in urban surface streams. For pest eradication, urban hard surfaces such as concrete are often directly treated with pesticides, and wind/water can also carry pesticides onto hard surfaces from surrounding areas. This study expanded on previous bench-scale studies by considering pesticide runoff caused by irrigation under dry weather conditions and rain during the wet season, and evaluated the effects of pesticide residence time on concrete, single versus recurring precipitations, precipitation intensity, and concrete surface conditions, on pesticide transferability to runoff water. Runoff from concrete 1 d after pesticide treatment contained high levels of bifenthrin (82 ?g/L) and permethrin (5143 ?g/L for cis and 5518 ?g/L for trans), indicating the importance of preventing water contact on concrete after pesticide treatments. Although the runoff transferability quickly decreased as the pesticide residence time on concrete increased, detectable residues were still found in runoff water after 3 months (89 d) exposure to hot and dry summer conditions. ANOVA analysis showed that precipitation intensities and concrete surface conditions (i.e., acid wash, silicone seal, stamping, and addition of microsilica) did not significantly affect the pesticide transferability to runoff. For concrete slabs subjected to natural rainfalls during the winter wet season, pesticide levels in the runoff decreased as the time interval between pesticide application and the rain event increased. However, bifenthrin and permethrin were still detected at 0.15-0.17 and 0.75-1.15 ?g/L in the rain runoff after 7 months (221 d) from the initial treatment. In addition, pesticide concentrations showed no decrease between the two rainfall events, suggesting that concrete surfaces contaminated by pesticides may act as a reservoir for pesticide residues, leading to sustained urban runoff contamination. PMID:22153959

The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. - Selected structural BMPs are recommended for reducing loads of OP pesticides.

The presence of pesticide residues in crops is a matter of global public concern, and simple, rapid, and reliable methods for pesticide residue analysis are essential to ensure food safety. In this review, I evaluate a commercially available kit-based enzyme-linked immunosorbent assay (ELISA), which uses specific or selective antigen-antibody interactions, for simple and rapid pesticide residue analysis in crops, particularly before shipment of the crops. The evaluated ELISAs were found to be sufficiently sensitive to detect three pesticides (imidacloprid, fenitrothion, and chlorothalonil) at levels close to the maximum residue limits. Simple dilution of sample extracts alone was sufficient to surmount the problem of matrix interference, which can be troublesome with ELISA. The average recovery rates of the three pesticides exceeded 84%, and the average coefficients of variation were less than 13% for all tested crop samples. The results obtained with the ELISAs correlated well with those obtained by reference chromatographic methods for all three pesticides (r > 0.96). These findings strongly suggest that ELISA is a suitable method for quantitative and reliable screening analysis of these pesticides in crops without the need for sample pretreatment. Elimination of this need can be expected to save time and money and considerably increase sample throughput.   

Multiple pesticide residues have been observed in some samples of canned foods, frozen vegetables, and fruit jam, which put the health of the consumers at risk of adverse effects. It is quite apparent that such a state of affairs calls for the need of more accurate, cost-effective, and rapid analytical techniques capable of detecting the minimum concentrations of the multiple pesticide residues. The aims of this paper were first, to determine the effectiveness of the use of Supercritical Fluid Extraction (SFE) and Supercritical Fluid Chromatography (SFC) techniques in the analysis of the levels of pesticide residues in canned foods, vegetables, and fruits; and second, to contribute to the promotion of consumer safety by excluding pesticide residue contamination from markets. Fifteen different types of imported canned and frozen fruits and vegetables samples obtained from the Houston local food markets were investigated. The major types of pesticides tested were pyrethroids, herbicides, fungicides, and carbamates. By using these techniques, the overall data showed 60.82% of the food samples had no detection of any pesticide residues under this investigation. On the other hand, 39.15% different food samples were contaminated by four different pyrethroid residues +/- RSD% ranging from 0.03 +/- 0.005 to 0.05 +/- 0.03 ppm, of which most of the pyrethroid residues were detected in frozen vegetables and strawberry jam. Herbicide residues in test samples ranged from 0.03 +/- 0.005 to 0.8 +/- 0.01 ppm. Five different fungicides, ranging from 0.05 +/- 0.02 to 0.8 +/- 0.1 ppm, were found in five different frozen vegetable samples. Carbamate residues were not detected in 60% of investigated food samples. It was concluded that SFE and SFC techniques were accurate, reliable, less time consuming, and cost effective in the analysis of imported canned foods, fruits, and vegetables and are recommended for the monitoring of pesticide contaminations. PMID:14755112

...Pesticide Petition Filed for Residues of Pesticide Chemicals in or on a Commodity...modification of regulations for residues of pesticide chemicals in or on the food...regulations in 40 CFR part 180 for residues of pesticide chemicals in or on the...

The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary¿secondary amine and graphitized carbon black) and large-volume (20 ¿L) injecti...

The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. PMID:19616876

... herbal dietary supplements for the presence of lead, arsenic, mercury, cadmium, organichlorine pesticides, and organophosphorous pesticides. Certain ... those, 32 also contained mercury, 28 cadmium, 21 arsenic, and 18 residues from at least one pesticide. ...

Modern agriculture depends on pesticides to curb infestations, increase crop yield and to produce the quantity and quality of food demanded by today's society. However, potential pesticide residue contamination of food is of critical concern to the food industry and the regulators responsible for health and safety. For example, many pesticides kill insects by attacking the central nervous system, and the use of these pesticides above the EPA set tolerance levels (from 0.1 to 50 ppm) could pose a threat to humans, in particular infants. Unfortunately, rapid, chemical analysis of pesticide residues is unavailable, and only a very small fraction of foods are inspected. The greatest concern is food imported from nations that simply ignore US regulations. In an effort to address this need, we have been developing a simple device to collect residues from food surfaces, perform a rapid chemical separation, and detect and identify pesticides by surface-enhanced Raman spectroscopy (SERS). Capillaries are coated with a metal-doped sol-gel that both separates chemicals and generates SER spectra when irradiated. SERS of pesticides at ppm concentrations, and a preliminary product to aid inspectors is presented.

Pesticides are a key component in protecting crops and producing the quantity of food required by today's world population. However, since excessive concentrations pose a threat to human health, the USA sets strict tolerance levels to ensure public safety. Unfortunately, many other countries ignore these regulations and imported food exceeding these levels or contaminated with banned pesticides is a common occurrence. Furthermore, rapid chemical analysis of pesticide residues is unavailable, and only a very small fraction of foods are inspected. The greatest concern is fruit, for which an estimated 12 million tons were imported in 2003. In an effort to address this need, we have been developing a simple and rapid procedure to analyze for pesticides on fruit surfaces or in the juice of fruits. The procedure employs metal-doped sol-gel filled capillaries that both chemically extracts the pesticide and generates surface-enhanced Raman spectra when irradiated. The SERS-active capillaries, sensitivity, and preliminary fruit analyses are presented.

Solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to determine pesticide residues in Chinese herbal formulations. Fibers coated with a 100-microm film thickness of poly(dimethylsiloxane) was used to extract 19 organochlorine pesticides (OCPs). The pesticides in the study consisted of alpha-, beta-, gamma-and delta-hexachlorocyclohexane, p,p'-DDD, p,p'-DDE, p,p'-DDT, o,p'-DDT, aldrin, dieldrin, endrin, endrin aldehyde, endrin ketone, endosulfan (I, II and sulfate), heptachlor, heptachlor epoxide, and methoxychlor. The optimal experimental procedures for the adsorption and desorption of pesticides were evaluated. The linearity was obtained with a precision below 11% RSD for the studied pesticides expect endosulfan sulfate (21%) in a wide range from 1 to 200 ng/g. Detection limits were reached at below ng/g levels. Heptachlor epoxide was determined at a calculated limit of 0.03 ng/g. Comparison between SPME and Soxhlet extraction showed that SPME has a less than one order detection limit for residue pesticide determination. The proposed method was tested by analyzing herbal formulations from a local market for OCP multiresidues. Some residues studied were detected in the analyzed samples. The results demonstrate the suitability of the SPME-GC-MS approach for the analysis of multi-residue OCPs in Chinese herbal formulations. PMID:11117422

Compared to generally used solvent extraction methods, supercritical fluid extraction (SFE) with carbon dioxide has the advantages of automation and simple operation in preparing samples for pesticide residue analysis. This report is the outcome of our evaluation of the practicality of SFE for the preparation of samples for pesticide residue analysis. We studied the recovery of 303 compounds with several crops by a simultaneous analytical method of SFE, cartridge column purification, followed by GC/MS determination. We achieved 70 to 120% recovery for more than 80% of the examined compounds.   

BACKGROUND: Pesticide residues remaining on food represent a potential risk to consumer's health. Determination of these pesticide residues involves tedious procedures of analysis with regard to time and laboratory work. Near-infrared spectroscopy (NIRS) is a possible alternative to these methods. The aim of this research was to evaluate the ability of NIRS to classify two pesticides used for controlling apple fruit pests according to their concentration. Different solutions were prepared, based on the dose recommended by the pesticide producers for apple pest treatments. Spectra were acquired on a spectrophotometer from liquid samples belonging to these solutions. RESULTS: Calibration models were developed from liquid samples, following the soft independent modelling of class analogy (SIMCA) analysis method. These models classified between 99 and 100% of the validation samples belonging to different pesticide concentration solutions even at the maximum residue limit level of these products in apple fruit. CONCLUSIONS: NIRS technology shows a high potential for identifying pesticides in liquid samples, according to their concentration, at the levels required by the legislation. Copyright © 2012 Society of Chemical Industry. PMID:22997066

Despite the importance of pesticide usage for the food production, its indiscriminate use may cause changes in the soil fertility, because pesticides influence soil microorganisms which are important for the biogeochemical cycles. The influence of applications of several pesticides, as recommended for cotton culture, was studied on the bioactivity of different soils (from Sao Paulo and Tatui, SP) by using radiometric techniques and a closed system for detection of bio mineralization of ''1{sup 4}C-2,4-D ({sup 14}C-2,4-dichlorophenoxyacetic acid) and production of {sup 14}C-volatile compounds. The {sup 14}C-2,4-D dissipation under influence of other pesticide applications was also studied by determination of {sup 14}C-extractable residues, {sup 14}C-bound residues and qualitative and quantitative analysis of the {sup 14}C-extractable residues by high pressure liquid chromatography (HPLC) and thin layer chromatography (TLC). {sup 14}C-volatile compounds were never detected but increases and decreases of bio mineralization were detected in both soils after different treatments. The mixture of deltamethrin + methyl parathion increased significantly the bioactivity in both soils; nevertheless, monocrotophos did not have any influence. The applications of different pesticides have also influenced the {sup 14}C-2,4-D dissipation, because the radiocarbon recovered as {sup 14}C-extractable residues differed between the treated and untreated samples of both soils. On the other hand, the pesticide applications did not influence the production of {sup 14}C-bound residues. This {sup 14}C-residue was produced in larger amounts by the richest in organic matter soil (Sao Paulo). Although radiocarbon had been detected not only as {sup 14}'C-2,4-D but also as a {sup 14}C-metabolite, in both soils and treatments, results indicate that the '{sup 14}C-2,4-D dissipation varied in the two studied soils and was influenced by treatments with others pesticides. (author)

Objectives: To review the Australian tobacco industry's knowledge of pesticide residue on Australian tobacco and its policies and practices on resisting calls by tobacco control advocates that consumers should be informed about pesticide residue as well as additives.

A fast gas chromatography coupled with mass spectrometry (GC-MS) using large volume injection with programmed temperature vaporizer in solvent vent mode (PTV-LVI-SV) was developed for the trace determination of multiple pesticide residues in traditional Chinese medicines (TCMs). Experimental conditions of PTV-LVI-SV injection were optimized by central composite design. The optimized result was that initial temperature was held at 40°C for 39 s, vent flow rate was set at 45 mL/min and vent pressure was held at 0 psi for 36 s, injection volume was 10 ?L. Furthermore, the quick and effective QuEChERS (quick, easy, cheap, effective, rugged and safe) method was performed to extract and purify pesticide residues in TCMs. The prepared samples were analyzed with GC-MS in the selected ion monitoring mode (SIM). The lowest LOD was 4 ?g/kg for some pesticides. The recoveries were checked by spiking samples with pesticides at 25, 50 and 250 ?g/kg. The average recoveries of most pesticides were from 80 to 118%. The result indicated that QuEChERS and PTV-LVI-SV GC-MS method was a rapid and sensitive analysis technique for the determination of multiple pesticide residues in TCMs. PMID:22012702

The dynamics of incurred pesticide residues in apples, variety Melrose, was monitored during their cold storage at 1-3degreeC for 5 months. Of 21 active ingredients contained in pesticide preparations applied within four experimental pre-harvest regimes, only six fungicides (captan, cyprodinyl, dodine, pyrimethanil, tebuconazole, tolyfluanid) and one insecticide (phosalone) were detected at the time of harvest. The other active ingredients - acetamiprid, chlorpyrifos-methyl, difenoconazole, diflubenzuron, dithianon, EBDCs (represented by mancozeb and thiram in this study), fenoxycarb, kresoxim-methyl, teflubenzuron, thiacloprid, triazamate, trifloxystrobin and triflumuron did not exceed detection limit of LC-MS/MS or GC-MS methods used for sample analysis. Successive decrease of residues o...

This review covers the literature on pesticide analysis published or abstracted in the period between December 15, 1984, and December 15, 1986. The major sources of information were the primary abstracting journals Chemical Abstracts and Analytical Abstracts. Journals that were searched directly include the Journal of the Association of Official Analytical Chemists, Journal of Agricultural and Food Chemistry, Bulletin of Environmental Contamination and Toxicology, Analytical Chemistry, and the Journal of Chromatography (including its bibliography issues). The review is devoted mainly to methods for the determination of residues of pesticides and related compounds in a wide variety of samples and the analysis of pesticide standards. Analyses of pesticide formulations are not covered. The attempt was made to choose the most important publications describing methodology, instrumentation, and applications that would be readily available to readers to this Journal. Abstract citations are given for references from the more obscure journals and those not published in English.

A simple and rapid screening method of 95 acidic pesticides in agricultural products was developed. As acidic pesticides adsorb on the primary secondary amine mini-column with fatty acids which become interfering peaks during GC/MS analysis, they were not included in multi-residue analysis entailing PSA clean-up. In this study, the intermediate extracted solutions before PSA clean-up were analyzed by LC/TOF-MS. Accurate mass measurement of TOF-MS enabled the detection of molecular ions and fragment ions with high selectivity. Mean recoveries of 95 pesticides added to 6 agricultural products at 0.1 ?g/g were 49–127% with RSD <20%. Limits of quantitation were 0.01–0.02 ?g/g for 95 pesticides. The method was applied to 140 samples, and 2,4-D from lemon and orange, fluazifop from baby kidney bean, dichlorprop from apple were detected, respectively, at 0.02–0.03 ?g/g below MRLs. The proposed method showed good sensitivity for 95 acidic pesticides and enabled rapid screening in combination with our multi-residue method targeted to 520 pesticides.   

A rapid method using programmed temperature vaporizer injection–low-pressure gas chromatography–high-resolution time-of-flight mass spectrometry (PTV–LP-GC–HRTOFMS) for the analysis of multiple pesticide residues in fruit-based baby food was developed. The fast and inexpensive buffered QuEChERS ext...

This data base is a computer file containing all Italian scientific papers dealing with pesticide residues, metabolites and similar products in foods and in the environment. It was first published in 1978. As of today, 321 papers have been filed and they furnish complete bibliographic references, active ingredient names, conditions of treatment, sampling and analysis. All analytical data have also been filed.

Efficient clean-up is indispensable for preventing matrix effects in multi-residue analysis of pesticides in food by liquid and gas chromatography (LC and GC) coupled to mass spectrometry (MS). High-throughput planar solid phase extraction (HTpSPE) was recently introduced as a new clean-up concept in residue analysis of pesticides in fruit and vegetables (C. Oellig, W. Schwack, 2011 [45]). Thin-layer chromatography (TLC) was used to completely separate pesticides from matrix compounds and to focus them into a sharp zone, followed by extraction of the target zone by the TLC-MS interface. As rather challenging matrices, tea samples were chosen in this study. Besides chlorophylls and polyphenols, high amount of caffeine is co-extracted resulting in strong matrix effects both in LC-MS and GC-M...

In this work, an analytical method for GC using direct solid sample introduction was developed to tackle the problem regarding quick detection of pesticide residue in crops and large-scale screening of samples. 10mg of the crop solid sample without sample pre-treatment was directly introduced into a modified split/splitless injector for GC analysis. A split/splitless injector was modified to quickly remove oxygen and low boiling-point matrices of the sample. The whole sampling procedure was simple and it required less than 5 min. The experimental parameters including injector-port temperature, removal of oxygen and low boiling point matrices, size and the amount of the solid sample, oven temperature program were studied. Satisfactory recoveries of 6 pesticides (methyl parathion, fenitrothion, aldrin, dieldrin, endosulfan, o,p'-DDT) were obtained in maize and rice sample. Relative standard deviation was less than 15%. Experimental results showed that the proposed method was quick and reliable for pesticide residues analysis in crops. PMID:21872016

Combination techniques such as gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) are commonly used for pesticide residue analysis, but there is no reported method for the simultaneous analysis of multiple pesticides in a sample using a single instrument. Supercritical fluid chromatography (SFC) offers high resolution at high flow rates and various separation modes and hence may aid the rapid simultaneous analysis of pesticide. We developed an SFC/MS/MS method and analyzed 17 pesticides with a wide range of polarities (logP(ow)=-4.6 to 7.05) and molecular weights (112.1-888.6) within 11min using a polar-embedded reversed-phase column. To the best of our knowledge, there is no previous report on the SFC analysis of a wide variety of compounds, including highly hydrophilic ones. By SFC, diquat dibromide (logP(ow)=-4.6), together with cypermethrin (logP(ow)=6.6) and tralomethrin (logP(ow)=5.05), could be detected in the presence of various other pesticides using a single mobile phase. SFC/MS allows for the rapid and simultaneous analysis of low concentrations (ng/L levels) of pesticides that typically need to be analyzed by GC/MS and LC/MS separately. PMID:23102524

Regarding environmental hygiene, as the pesticides in current use have high solubility in water, pesticides applied to paddy-field soil are detected in river water. Their residual potentials are low and the residual period in river water ranges from two weeks to one month.Regarding food hygiene, a number of pesticides in current use have been detected in vegetables and fruits. The number of cases in which pesticides are detected in vegetables and fruits at above the minimum residue level is very small.   

More than 700 pesticides are approved for use around the world, many of which are suspected endocrine disrupters. Other pesticides, though no longer used, persist in the environment where they bioaccumulate in the flora and fauna. Analytical methods target only a subset of the possible compounds. The analysis of food and environmental samples for pesticides is usually complicated by the presence of co-extracted natural products. Food or tissue extracts can be exceedingly complex matrices that require several stages of sample cleanup prior to analysis. Even then, it can be difficult to detect trace levels of contaminants in the presence of the remaining matrix. For efficiency, multi-residue methods (MRMs) must be used to analyze for most pesticides. Traditionally, these methods have relied upon gas chromatography (GC) with a constellation of element-selective detectors to locate pesticides in the midst of a variable matrix. GC with mass spectral detection (GC/MS) has been widely used for confirmation of hits. Liquid chromatography (LC) has been used for those compounds that are not amenable to GC. Today, more and more pesticide laboratories are relying upon LC with mass spectral detection (LC/MS) and GC/MS as their primary analytical tools. Still, most MRMs are target compound methods that look for a small subset of the possible pesticides. Any compound not on the target list is likely to be missed by these methods. Using the techniques of retention time locking (RTL) and RTL database searching together with spectral deconvolution, a method has been developed to screen for 567 pesticides and suspected endocrine disrupters in a single GC/MS analysis. Spectral deconvolution helps to identify pesticides even when they co-elute with matrix compounds while RTL helps to eliminate false positives and gives greater confidence in the results.

Abstract in english Pesticides, aflatoxins, and nutritional analyses of commercial citrus pulp pellets in Brazil were performed in samples from São Paulo State. They were stored during 86 days and were processed for detection of toxic agents. Residual pesticides (organochlorinated, organophosphorus, pyrethoids, carbamates, chloroalquil tio fungicides, triazols, and the miscellaneous compound propargit) and aflatoxins (B1, B2, G1 and G2) were assayed at 0, 43 and 86 days of storage. It was n (more) ot detected residual pesticide and aflatoxins in any sample. The analysis indicated reduced levels of phosphorous and high values of calcium. Assessment of micro minerals indicated the presence of aluminum, barium, titanium, cooper, manganese, thorium, vanadium, zinc, lanthanum, samarium, cobalt, antimony, arsenic, and scandium.

...EPA-HQ-OPP-2011-0082; FRL-8871-1] Withdrawal of Pesticide Petitions for Residues of Pesticide Chemicals in or on Various Commodities AGENCY...regulations in 40 CFR Part 174 or Part 180 for residues of pesticide chemicals in or on various food...

Multiresidue methods (MRMs) for pesticides residues determination in fruit and vegetables, based on GC-MS, are mainly performed in electron impact ionization mode. However an important group of them provide much better response working in negative chemical ionization mode due to the elimination of a high percentage of background signal. Considering that a selective and sensitive method has been developed for the determination of multiclass pesticide residues in different commodities by GC-MS with a triple stage quadrupole analyzer (GC-TSQ-MS); the pesticide signal has been optimized in MS-MS whilst working in negative chemical ionization mode using methane as the reagent gas. The proposed method was fully validated for 53 compounds in tomato, apple and orange matrices. The obtained limits of determination were lower than 0.1?g/kg for more than 50% of the pesticides studied, and lower than 1?g/kg for all pesticides studied, except for cypermethrin, boscalid, bifenthrin and deltamethrin. Linearity was studied in the 0.5-50?g/kg range and a linear response was obtained for all pesticides in all matrices. Recoveries were evaluated at two different levels (1 and 50?g/kg) and recoveries were ranged between 70 and 120% in tomato, apple and orange, except in the cases of chlorfenapyr, ofurace, chlozolinate, chlorothalonil, tolylfluanid and dichlofluanid with recovery values close to 60% at 1?g/kg fortification levels. Repetitivity was evaluated and the relative standard deviation (RSD%) was lower than 10% in all cases. The developed method was employed in the analysis of real samples intended for baby food and the obtained results showed that 50% of the samples were positive for different pesticide residues. The concentration range detected was between 5 and 100?g/kg. The positive detection of OCs was particularly noticeable; these included chlorothalonil, fenhexamide, clorpyrifos and lambda cyhalothrin, which are very persistent and toxic with low acute reference dose. Endosulfan sulfate, which is not approved, was detected at a low concentration. PMID:23058941

In this study, a new gas chromatography-mass spectrometry (GC-MS) method, using the very selective negative chemical ionization (NCI) mode, was developed and applied in combination with a modified acetonitrile-based extraction method (QuEChERS) for the analysis of a large number of pesticide residues (51 pesticides, including isomers and degradation products) in green coffee beans. A previously developed integrated sample homogenization and extraction method for both pesticides and mycotoxins analysis was used. An homogeneous slurry of green milled coffee beans and water (ratio 1:4, w/w) was prepared and extracted with acetonitrile/acetic acid (1%), followed by magnesium sulfate addition for phase separation. Aliquots from this extract could be used directly for LC-MS/MS analysis of mycoto...

...FRL-8841-9] Spiromesifen; Pesticide Tolerances AGENCY: Environmental...residues of spiromesifen in or on leaf...equivalent of spiromesifen, in or on...use of the pesticide pursuant to...exemptions. The tolerances expire...

...proposes to establish tolerances in 40 CFR part...the insecticide spiromesifen; 2-oxo-3...inert ingredient in pesticide formulations...under the following tolerance exemption descriptor...requirement of a tolerance for residues of...used to formulate pesticides applied to...

...Environmental Media Pesticide Root Zone Model--Ground Water (PRZM-GW) Update...Water Residues in California Central Coast Lettuce Production Areas Hybrid PRZM: ``Filling...kinetics, Exposure assessment, Pesticide models, Pronamide, PRZM, Watershed...

A method to determine six pesticides applied in soy cultivation (imazethapyr, imazaquin, metsulfuron-methyl, carboxin, chlorimuron-ethyl, and tebuconazole) using matrix solid phase dispersion (MSPD) as the extraction technique followed by a clean-up step, using a C8 co-column, and subsequent chromatographic analysis by high performance liquid chromatography diode array detection (HPLC-DAD) was developed. The validated method showed good recuperation for all pesticides (60-120%), except for metsulfuron-methyl and tebuconazole at their lowest concentration levels, and the quantification limits of the method (0.04-0.08 µg g-1) were below the maximum residue limits imposed by the principal regulatory agencies.

We illustrate the potential of liquid chromatography with (quadrupole) time-of-flight mass spectrometry [LC-(Q)TOF-MS] in investigating the presence of pesticide metabolites in food and water samples. The higher polarity of metabolites compared to their parent pesticides makes the combination of LC [both high-performance (HPLC) and ultra-performance (UPLC)] with TOF-MS one of the most appropriate techniques for their analysis, mainly from a qualitative point of view. Both target analysis and non-target analysis have been explored making use of this technique. Target analysis is typically applied in the inspection of maximum residue limits in food, when a relevant metabolite is included in the residue definition for toxicological reasons or its presence in significant amounts. Within this f...

This manual describes techniques for obtaining reliable residue samples for forestry environmental studies on aerially applied hexazinone and glyphosphate, although they may also apply to other pesticide residues and studies on their environmental fate. Materials and methods, including preparation of sampling plots, and sample collection, packaging, shipping and storage, are described for assessing spray deposition and monitoring herbicide in stream water, suspended sediments, streambed sediments, soils and foliage/leaf-litter. Pre-analysis preparation of deposition and soil samples, and reporting of residue data for all substrates are also described.

Abstract in english This paper describes the use of pesticides in agriculture. Research has shown that significant quantities of pesticide residues have been found in many types of foods. Thus, an overview is given of pesticide residue determinations in fruits and vegetables, with special attention to apples. The toxicity and the adverse effects possibly caused by the exposure of these compounds are alerting the scientific community to develop studies about the validation of analytical metho (more) ds for multiresidue pesticide determination in these samples. This review shows that pesticide-residue determination in apples is becoming a very important and challenging issue.

In the analytical analysis the measurement uncertainty is a quantitative indicator of the confidence describing the range around a reported or experimental result within which the true value can be expected. Several approaches can be used to estimate the measurement uncertainty associated to the analysis of pesticide residues: a) the top-down, the estimation can be referred to default values; b) the bottom-up the estimation is related to the uncertainty sources. Concerning the bottom-up approach, the following contributions have been investigated: weight of sample, calibration solutions, final volume of sample and intermediate repeatability studies. The commodity/residue combination selected in this study was celery/tau-fluvalinate pesticide. Tau-fluvalinate is a broad-spectrum insecticide in the pyrethroid class of pesticides. The Maximum Residue Limit (MRL) of tau-fluvalinate in celery has been set at 0.01 mg/kg. The tau- Fluvalinate showed two chromatographic peaks. Since the individual standards are not available, the two peaks were integrated separately and the instrumental responses were added. The total residue was calculated on the basis of resulted peaks. The present work aims to compare the uncertainty estimated by experimental data using repeated analysis (n = 12) of a real sample and a spiked sample. The relative expanded uncertainty for two data set, incurred and spiked, was 22 % and 20 %, respectively. No differences were observed from repeated determinations of real samples and spiked samples. PMID:22575007

A sensitive and efficient solid-phase microextraction method, based on liquid chromatography and UV-Vis detection, was developed and validated as an alternative method for sample screening prior to LC-MS analysis. It enables the simultaneous determination of ten pesticides in mango fruits. The fiber used was polydimethylsiloxane while optimum SPME conditions employed have been developed and optimized in a previous work. The desorption process was performed in static mode, using acetonitrile as a solvent. The results indicate that the DI-SPME/HPLC/UV-Vis procedure resulted in good linear range, accuracy, precision and sensibility and is adequate for analyzing pesticide residues in mango fruits. The limits of detection (0.6-3.3??g/kg) and quantification (2.0-10.0??g/kg) were achieved with values lower than the maximum residue levels (MRLs) established by Brazilian legislation for all pesticides in this study. The average recovery rates obtained for each pesticide ranged from 71.6 to 104.3% at three fortification levels, with the relative standard deviation ranging from 4.3 to 18.6%. The proposed method was applied for the determination of the aforementioned compounds in commercial mango samples and residues of azoxystrobin, fenthion, permethrin, abamectin and bifenthrin were detected in the mango samples, although below the MRLs established by Brazilian legislation. PMID:21919197

An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO(2) volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO(2), 300 atm, and 50 degrees C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides. PMID:17763038

In this work, the capability of gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF MS) for quantitative analysis of pesticide residues has been evaluated. A multiclass method for rapid screening of pesticides (insecticides, acaricides, herbicides and fungicides) in fruit and vegetable matrices has been developed and validated, including detection, identification and quantification of the analytes. To this aim, several food matrices were selected: high water content (apples, tomatoes and carrots), high acid content (oranges) and high oil content (olives) samples. The well known QuEChERS procedure was applied for extraction of pesticides, and matrix-matched calibration using relative responses versus internal standard was used for quantification. The sample extracts were ...

A new material based on poly(methyltetradecylsiloxane) (PMTDS) thermally immobilized onto a silica support has been tested as a sorbent for the solid-phase extraction (SPE) from water of several pesticides used in soybean cultivation. The SPE methodology was developed and validated for six of these pesticides (imazethapyr, imazaquin, metsulfuron-methyl, bentazone, chlorimuron-ethyl and tebuconazole) according to the International Conference on Harmonization directives and the results were compared with those obtained with a commercial C18 SPE cartridge. The PMTDS-based sorbent gives results similar to the commercial sorbent with recoveries and precisions in agreement with directives for residue analysis. The quantification limits, after concentration, of all the pesticides evaluated were 1.0 microg L(-1), below the levels imposed by the principal regulatory agencies. The PMTDS-based sorbent preparation is fast, easy and reproducible and the cartridges are less expensive than similar commercial SPE materials. PMID:17386471

...is a member of the neonicotinoid class of pesticides...metabolite of another neonicotinoid, thiamethoxam...thyroid colloid with imidacloprid). Thus, there...for residues of the insecticide clothianidin,...

...residues of the agricultural bactericide...of the National Technology Transfer and Advancement Act of 1995 (NTTAA...and procedure, Agricultural commodities, Pesticides...on the specified agricultural commodities,...

The determination of pesticide residues in food matrices is a formidable challenge mainly because of the small quantities of analytes and large amounts of interfering substances which can be co-extracted with analytes and, in most cases, adversely affect the results of an analysis. However, safety concerns require that pesticides of the wide range of chemical properties (including acidic, basic and neutral) should be monitored. Because of the wide variety of food matrices, the sample must initially be cleaned up before final analysis. That is why the analytical chemist is faced with the need to devise new methodologies for determining such residues to be determined in a single analytical run. To accomplish the goal, QuEChERS methodology has been developed. It is a streamlined and effective...

There is a current trend for many laboratories to develop and use qualitative gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) based multi-residue methods (MRMs) in order to greatly increase the number of pesticides that they can target. Before these qualitative MRMs can be used for the monitoring of pesticide residues in food, their fitness-for-purpose needs to be established by initial method validation. This paper sets out to assess the performances of two such qualitative MRMs against a set of parameters and criteria that might be suitable for their effective validation. As expected, the ease of detection was often dependent on the particular pesticide/commodity combinations that were targeted, especially at the lowest concentrations tested (0.01 mg/kg). The two examples also clearly demonstrated that the percentage of pesticides detected was dependent on many factors, but particularly on the capabilities of the automated software/library packages and the parameters and threshold settings selected for operation. Another very important consideration was the condition of chromatographic system and detector at the time of analysis. If the system was relatively clean, then the detection rate was much higher than if it had become contaminated over time from previous injections of sample extracts. The parameters and criteria suggested for method validation of qualitative MRMs are aimed at achieving a 95% confidence level of pesticide detection. However, the presence of any pesticide that is 'detected' will need subsequent analysis for quantification and, depending on the qualitative method used, further evidence of identity. PMID:22851355

...support granting of the pesticide petitions. Additional...determination on these pesticide petitions. Pursuant...regulations for residues of pesticides in or on food commodities...in this unit. New Tolerances 1. PP 0E7684. (EPA-HQ-OPP-2009-0682...of the insecticide spiromesifen,...

The ecotoxicological assessment of pesticide effects in the aquatic environment should normally be based on a deep knowledge of not only the concentration of pesticides and metabolites found but also on the influence of key abiotic and biotic processes that effect rates of dissipation. Although the bioconcentration and bioaccumulation potentials of pesticides in aquatic organisms are conveniently estimated from their hydrophobicity (represented by log K(ow), it is still indispensable to factor in the effects of key abiotic and biotic processes on such pesticides to gain a more precise understanding of how they may have in the natural environment. Relying only on pesticide hydrophobicity may produce an erroneous environmental impact assessment. Several factors affect rates of pesticide dissipation and accumulation in the aquatic environment. Such factors include the amount and type of sediment present in the water and type of diet available to water-dwelling organisms. The particular physiological behavior profiles of aquatic organisms in water, such as capacity for uptake, metabolism, and elimination, are also compelling factors, as is the chemistry of the water. When evaluating pesticide uptake and bioconcentration processes, it is important to know the amount and nature of bottom sediments present and the propensity that the stuffed aquatic organisms have to absorb and process xenobiotics. Extremely hydrophobic pesticides such as the organochlorines and pyrethroids are susceptible to adsorb strongly to dissolved organic matter associated with bottom sediment. Such absorption reduces the bioavailable fraction of pesticide dissolved in the water column and reduces the probable ecotoxicological impact on aquatic organisms living the water. In contrast, sediment dweller may suffer from higher levels of direct exposure to a pesticide, unless it is rapidly degraded in sediment. Metabolism is important to bioconcentration and bioaccumulation processes, as is detoxification and bioactivation. Hydrophobic pesticides that are expected to be highly stored in tissues would not be bioconcentrated if susceptible to biotic transformation by aquatic organisms to more rapidly metabolized to hydrophilic entities are generally less toxic. By analogy, pesticides that are metabolized to similar entities by aquatic species surely are les ecotoxicologically significant. One feature of fish and other aquatic species that makes them more relevant as targets of environmental studies and of regulation is that they may not only become contaminated by pesticides or other chemicals, but that they constitute and important part of the human diet. In this chapter, we provide an overview of the enzymes that are capable of metabolizing or otherwise assisting in the removal of xenobiotics from aquatic species. Many studies have been performed on the enzymes that are responsible for metabolizing xenobiotics. In addition to the use of conventional biochemical methods, such studies on enzymes are increasingly being conducted using immunochemical methods and amino acid or gene sequences analysis. Such studies have been performed in algae, in some aquatic macrophytes, and in bivalva, but less information is available for other aquatic species such as crustacea, annelids, aquatic insecta, and other species. Although their catabolizing activity is often lower than in mammals, oxidases, especially cytochrome P450 enzymes, play a central role in transforming pesticides in aquatic organisms. Primary metabolites, formed from such initial enzymatic action, are further conjugated with natural components such as carbohydrates, and this aids removal form the organisms. The pesticides that are susceptible to abiotic hydrolysis are generally also biotically degraded by various esterases to from hydrophilic conjugates. Reductive transformation is the main metabolic pathway for organochlorine pesticides, but less information on reductive enzymology processes is available. The information on aquatic species, other than fish, that pertains to bioconcentration factors, metabolism, and elimination is rather limited in the literature. The kinds of basic information that is unavailable but is needed on important aquatic species includes biochemistry, physiology, position in food web, habitat, life cycle, etc. such information is very important to obtaining improved ecotoxicology risk assessments for many pesticides and other chemicals. More research attention on the behavior of pesticides in, and affect on many standard aquatic test species (e.g., daphnids, chironomids, oligochaetes and some bivalves) would particularly be welcome. In addition to improving ecotoxicology risk assessments on target species, such information would also assist in better delineating affects on species at higher trophic levels that are predaceous on the target species. There is also need for designing and employing more realistic approaches to measure bioconcentration and bioaccumulation, and ecotoxicology effects of pesticides in natural environment. The currently employed steady-state laboratory exposure studies are insufficient to deal with the complexity of parameters that control the contrasts to the abiotic processes of pesticide investigated under the strictly controlled conditions, each process is significantly affected in the natural environment not only by the site-specific chemistry of water and sediment but also by climate. From this viewpoint, ecotoxicological assessment should be conducted, together with the detailed analyses of abiotic processes, when higher-tier mesocosm studies are performed. Moreover, in-depth investigation is needed to better understand the relationship between pesticide residues in organisms and associated ecotoxicological endpoints. The usual exposure assessment is based on apparent (nominal) concentrations fo pesticides, and the residues of pesticides or their metabolites in the organisms are not considered in to the context of ecotoxicological endpoints. Therefore, more metabolic and tissue distribution information for terminal pesticide residues is needed for aquatic species both in laboratory settings and in higher-tier (microcosm, mesocosm) studies. PMID:19957234

In this study, nerve conduction, organochlorine (OC) pesticide residues in blood and cholinesterase activity levels of pesticide sprayers employed in mango plantations at Lucknow, North India, were determined. Fifty-two sprayers from mango plantations who regularly spray mixture of pesticides like organophosphates (OP), OCs, and carbamates were considered as exposed group. Eighteen subjects with similar socio-economic status of exposed group, who do not handle pesticides, were selected as controls. Questionnaire-based interviews related to personal and occupational histories of the study subjects were carried out. Sprayers did not use any personal protective equipment during pesticide handling. The blood-pesticide analyses of sprayers show higher mean values of hexachlorohexane (HCH), ...

Abstract Worldwide pesticide usage has increased dramatically during the last three decades, coinciding with changing practices and increasing by intensive agriculture. This widespread use of pesticides for agricultural and non-agricultural purposes has resulted in the presence of their residues in various environmental matrices. The occurrence of pesticides and their metabolite transported in rivers, channels, lakes, sea, air, soils, groundwater, and even drinking water, proves the high risk of these chemicals to human health and the environment. Therefore, pesticide removal is of an increasing concern. In this study, a review of the published literature dealing with pesticides removal process is presented. Firstly, pesticide removal by conventional means is briefly considered. Secondly, ...

A gas chromatography-mass spectrometry (GC-MS) analytical method was developed for simultaneously determining 186 pesticides in tea matrices using analyte protectants to counteract the matrix-induced effect. The matrix effects were evaluated for green, oolong and black tea, representing unfermented, partially fermented and completely fermented teas respectively and depending on the type of tea, 72%, 94% and 94% of the pesticides presented strong response enhancement effect. Several analyte protectants as well as certain combinations of these protectants were evaluated to check their compensation effects. A mixture of triglycerol and d-ribonic acid-?-lactone (both at 2mg/mL in the injected samples) was found to be the most effective in improving the chromatographic behavior of the 186 pesticides. More than 96% of the 186 pesticides achieved recoveries within the range of 70-120% when using the selected mixture of analyte protectants. The simple addition of analyte protectants offers a more convenient solution to overcome matrix effects, results in less active sites compared to matrix-matched standardization and can be an effective approach to compensate for matrix effects in the GC-MS analysis of pesticide residues. PMID:23102633

Residue levels of azoxystrobin, acrinathrin and kresoxim methyl were determined in zucchini grown in an experimental greenhouse during a two weeks period in which repeated treatments with the three pesticides were applied. Analysis was carried out by using ethyl acetate extraction and gas chromatography with electron capture detection (GC-ECD). The maximum values of residues determined in the plantation were 1.87 mg/kg for azoxystrobin, 0.25 mg/kg for acrinathrin and 0.20 mg/kg for kresoxim methyl. The application of three different household processing (washing, peeling and cooking) and the study of ''unit to unit'' variability of these pesticides in zucchini were also carried out. The washing processing factors resulted to be 0.3, 0.2 and 0.0 for acrinathrin, azoxystrobin and kresoxim me...

It would be preferable for pesticide residues substituted by hydrolyzable functionality to be analyzed after cooking because their structures are apt to degrade during boiling and/or heating. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantitative determination of 44 pesticide residues with hydrolyzable functional group in five typical vegetable widely consumed in Republic of Korea is described. The sample clean-up was carried out according to the method of Food Code No. 83 established by the Korea Food and Drug Administration (KFDA). Zorbox XDB-C18 column was selected for the analysis because of the best peak separation. The LC mobile phase consisted of water and 5 mM methanolic ammonium formate, which resulted in a peak shape with good symmetry at each run...

A gas chromatography-exact mass time-of-flight mass spectrometry (GC-TOF-MS) method has been developed for the quantification of approximately one hundred pesticides in baby food, pear and lettuce samples. Prior to analysis, co-extractives were removed from acetonitrile:toluene (80:20) extracts using dispersive solid-phase extraction with primary secondary amine (50mg) and carbon sorbent (50mg). The concentration of pesticides in the extracts was measured using an extracted mass chromatogram window of 0.05 Th. Samples spiked with pesticides at 0.01 and 0.1 mgkg(-1) yielded average recoveries in the range of 70-109% with relative standard deviations less than 26% and displayed good linearity for the majority of the analytes. The method was applied to the screening of pear and lettuce samples for pesticide residues. Targeted quantification and exact mass peak detection, deconvolution and library searching packages were used successfully to detect and identify incurred residues present in the samples at concentrations above 0.01 mgkg(-1). The new feature dynamic range enhancement, improved mass accuracy, and hence detection and quantification of the analytes across the concentration range studied. PMID:17727866

The current paper provides an analysis of the potential number of cancer cases that might be prevented if half the U.S. population increased its fruit and vegetable consumption by one serving each per day. This number is contrasted with an upper-bound estimate of concomitant cancer cases that might be theoretically attributed to the intake of pesticide residues arising from the same additional fruit and vegetable consumption. The cancer prevention estimates were derived using a published meta-analysis of nutritional epidemiology studies. The cancer risks were estimated using U.S. Environmental Protection Agency (EPA) methods, cancer potency estimates from rodent bioassays, and pesticide residue sampling data from the U.S. Department of Agriculture (USDA). The resulting estimates are that approximately 20,000 cancer cases per year could be prevented by increasing fruit and vegetable consumption, while up to 10 cancer cases per year could be caused by the added pesticide consumption. These estimates have significant uncertainties (e.g., potential residual confounding in the fruit and vegetable epidemiologic studies and reliance on rodent bioassays for cancer risk). However, the overwhelming difference between benefit and risk estimates provides confidence that consumers should not be concerned about cancer risks from consuming conventionally-grown fruits and vegetables. PMID:22981907

Herbal formulations are getting popular throughout the world and commercialized extensively for various medicinal properties. WHO has emphasized the need for quality assurance of herbal products, including testing of heavy metals and pesticides residues. In view of WHO guidelines, single herbal drugs used in herbal formulations were collected from local market, for testing heavy metals and persistent pesticides residue. Therefore, in the present case, we have examined few local samples of certain herbs viz. Emblica officinalis, Terminalia chebula, Terminalia belerica, and Withania somnifera. The present studies were selected for estimation of four heavy metals namely Arsenic, Cadmium, Lead, and Mercury. Apart from these, pesticide residue Viz. Organochlorine pesticides, Organophosphorus pesticides, and Pyrethroids were analyzed in the four samples of single crude drugs. Heavy metals and pesticide residue were found below detection limits in all the samples. PMID:21210215

In Kazakhstan, there is a problem of finding ways to clean local sites contaminated with pesticides. In particular, such sites are the deserted and destroyed storehouses where these pesticides were stored; existing storehouses do not fulfill sanitary standards. Phytoremediation is one potential method for reducing risk from these pesticides. Genetic heterogeneity of populations of wild and weedy species growing on pesticide-contaminated soil provides a source of plant species tolerant to these conditions. These plant species may be useful for phytoremediation applications. In 2008-2009 and 2011, we surveyed substances stored in 80 former pesticide storehouses in Kazakhstan (Almaty oblast) to demonstrate an inventory process needed to understand the obsolete pesticide problem throughout the country, and observed a total of 354.7 t of obsolete pesticides. At the sites, we have found organochlorine pesticides residues in soil including metabolites of dichlorodiphenyltrichloroethane and isomers of hexachlorocyclohexane. Twenty-four of the storehouse sites showed pesticides concentrations in soil higher than maximum allowable concentration which is equal to 100 ?g kg(-1) in Kazakhstan. Seventeen pesticide-tolerant wild plant species were selected from colonizing plants that grew into/near the former storehouse's pesticides. The results have shown that colonizing plant annual and biannual species growing on soils polluted by pesticides possess ability to accumulate organochlorine pesticide residues and reduce pesticide concentrations in soil. Organochlorine pesticides taken up by the plants are distributed unevenly in different plant tissues. The main organ of organochlorine pesticide accumulation is the root system. The accumulation rate of organochlorine pesticides was found to be a specific characteristic of plant species and dependent on the degree of soil contamination. This information can be used for technology development of phytoremediation of pesticide-contaminated soils. PMID:22890508

...EPA-HQ-OPP-2010-0296; FRL-8876-4] Difenoconazole; Pesticide Tolerances AGENCY: Environmental...establishes tolerances for residues of difenoconazole in or on aspirated grain fractions...tolerances for residues of the fungicide difenoconazole, in or on carrot at 0.45...

... Fish Tissue Contaminant Level Data [NYDEC_fishtissuecontaminantdata]. This study was initiated to survey contaminant concentrations in fish found in NY ... Residue)" database contains pesticide residue data on raw and processed food.

...EPA-HQ-OPP-2008-0770; FRL-8820-3] Chlorantraniliprole; Extension of Time-Limited Pesticide...inadvertent residues of the insecticide chlorantraniliprole (3-bromo-N-[4-chloro-2-methyl-6...indirect or inadvertent residues of chlorantraniliprole in or on cowpea, forage and...

The uncertainty in pesticide residue levels (UPRL) associated with sampling size was estimated using individual acetamiprid and cypermethrin residue data from preharvested apple, broccoli, cabbage, grape, and sweet pepper samples. The relative standard deviation from the mean of each sampling size (n = 2(x), where x = 1-6) of randomly selected samples was defined as the UPRL for each sampling size. The estimated UPRLs, which were calculated on the basis of the regulatory sampling size recommended by the OECD Guidelines on Crop Field Trials (weights from 1 to 5 kg, and commodity unit numbers from 12 to 24), ranged from 2.1% for cypermethrin in sweet peppers to 14.6% for cypermethrin in cabbage samples. The percentages of commodity exceeding the maximum residue limits (MRLs) specified by the Japanese Food Sanitation Law may be predicted from the equation derived from this study, which was based on samples of various size ranges with mean residue levels below the MRL. The estimated UPRLs have confirmed that sufficient sampling weight and numbers are required for analysis and/or re-examination of subsamples to provide accurate values of pesticide residue levels for the enforcement of MRLs. The equation derived from the present study would aid the estimation of more accurate residue levels even from small sampling sizes. PMID:22475588

Pesticide spray concentrations in the plant canopy are typically difficult to measure because of large variation in deposition from the typical sprayer. This high variability is a serious problem because a good description of the fate of pesticide residues on plant foliage residues is a fundamental...

A multiresidue method based on normal-phase LC for the sample clean up of whale tissues extracts prior to GC-MS determination of residues of polychlorinated biphenyls, organochlorine pesticides and derivatives and lipophylic organophosphorus pesticides has been developed. Pesticides were extracted from blubber by fusing and dissolving the fat in n-hexane and from liver and kidney by reflux in n-hexane. Hexanic extracts were directly injected on the silicagel column of the automated LC clean up system, using n-hexane as mobile phase. Diode array detection allowed the on-line monitoring of lipids elution from the LC system. Purified extracts were analysed by GC using mass selective detection. The developed procedure was applied to different tissues from a whale specimen appeared in the Valencian coast, finding high concentrations of OCs (up to 7.3 micrograms g-1 pp'-DDE, and 7.2 micrograms g-1 PCBs). The method was validated by means of recovery tests for all the compounds detected in the whale and also for some other OCs and OPs studied in this paper. The method improves other current methods for the analysis of persistent organochlorines in marine mammals with regard to time of analysis, solvent expend and automation; solvent exchanges are not necessary before GC analysis, and it allows the simultaneous determination of organophosphorus pesticides. PMID:10519100

Flowing afterglow atmospheric pressure glow discharge tandem mass spectrometry (APGD-MS/MS) is used for the analysis of trace amounts of pesticides in fruit juices and on fruit peel. The APGD source was rebuilt after Andrade et al. (Andrade et al., Anal. Chem. 2008; 80: 2646-2653; 2654-2663) and mounted onto a hybrid quadrupole time-of-flight mass spectrometer. Apple, cranberry, grape and orange juices as well as fruit peel and salad leaves were spiked with aqueous solutions containing trace amounts of the pesticides alachlor, atrazine, carbendazim, carbofuran, dinoseb, isoproturon, metolachlor, metolcarb, propoxur and simazine. Best limits of determination (LODs) of pesticides in the fruit juices were achieved for metolcarb (1 microg/L in apple juice), carbofuran and dinoseb (2 microg/L in apple juice); for the analysis of apple skin best LODs were 10 pg/cm(2) of atrazine, metolcarb and propoxur which corresponds to an estimated concentration of 0.01 microg/kg apple, taking into account the surface area and the weight of the apple. The measured LODs were within or below the allowed maximum residue levels (MRLs) decreed by the European Union (1-500 microg/kg for pesticides in fruit juice and 0.01-5 microg/kg for apple skin). No sample pretreatment (extraction, pre-concentration, chromatographic separation) was necessary to analyze these pesticides by direct desorption/ionization using APGD-MS and to identify them using MS/MS. This makes APGD-MS a powerful high-throughput tool for the investigation of very low amounts of pesticides in fruit juices and on fruit peel/vegetable skin. PMID:18697232

A method using QuEChERS extraction and LC-MS/MS in electrospray positive ionisation mode was developed and validated for the analysis of 90 pesticides in a high water content matrix (tomato) in a single chromatographic run. To assess the intra-laboratory reproducibility of the method, validation was conducted on four different days by two different analysts. The validation data was treated using a spreadsheet developed in-house, which sets the most appropriate model for linear fit by determining whether the residuals of the calibration curves are homocedastic or heterocedastic. A statistical test for the significance of regression was also carried out. Calibration was always matrix-matched and the curves were obtained over the range 0.0075-0.10 or 0.020-0.125 mg kg(-1). Identification of analytes was based on retention times and MRM ratios. Recoveries were assessed at four different levels for each analyte and were between 73 and 106%, with relative standard deviations under reproducibility conditions of <20%. The measurement uncertainties of the method for each pesticide analysed were below 50%. Previous validation of the same method, applied to papaya samples and satisfactory results obtained in various proficiency tests with different high water content matrices, demonstrated the applicability of the method to these classes of commodities, without clean-up. The validated method will be applied routinely in the pesticide residues monitoring programme that constitutes the National Residue and Contaminant Control Plan of Brazil. PMID:22059454

The natural degradation of pyrethroids pesticides (bifenthrin and cyhalothrin) and benzoylurea pesticides (teflubenzuron, flufenoxuron and chlorfluazuron) in the leaves of Oolong tea trees and the effect of processing steps and pesticide's dose on the residue of above five pesticides in dried Oolong tea leaf samples were studied in detail by farm experiment and gas chromatography-mass spectrometry. The experimental results showed that: 1) Higher pesticide's dose used in tea planting will result in higher residue of pesticides in dried Oolong tea leaf samples, but the dose did not affect the degradation rate of pesticide. 2) The degradation of bifenthrin, cyhalothrin, teflubenzuron, flufenoxuron and chlorfluazuron in the leaves of tea trees follows zero-order kinetics with a half-life of 9....

Abstract in portuguese Propôs-se, com este trabalho, avaliar e monitorar a presença de agrotóxicos nas águas do canal São Gonçalo e do rio Piratini, localizados na região sul do Estado do Rio Grande do Sul. Durante o cultivo do arroz irrigado foram coletadas, em cinco datas diferentes, três amostras de água do rio Piratini e quatro do canal São Gonçalo. A metodologia empregada na análise dos resíduos de quinclorac, carbofuran e clomazone, foi a Cromatografia Líquida de Alta Efici? (more) ?ncia com Detecção por Arranjo de Diodos (HPLC-DAD) e, para os resíduos de fipronil e betaciflutrina, a Cromatografia Gasosa com Detecção por Captura de Elétrons (GC-ECD). Os resultados mostraram que da semeadura à colheita a quantidade de resíduos de agrotóxicos na água diminuiu; observou-se também que no ponto mais baixo (Laranjal), maior número de análises de águas com resíduos foi detectado (onze análises com resíduo de agrotóxico). O inseticida carbofuran e o herbicida quinclorac foram os produtos que apresentaram resíduos com maior freqüência (16 e 15, respectivamente) enquanto o clomazone e o fipronil indicaram sete amostras com resíduos cada uma e a betaciflutrina não foi detectada em nenhum local. Abstract in english The objective of this study was to evaluate and to monitor the presence of pesticides in the waters of the São Gonçalo channel and the Piratini river located in the southern region of the State of Rio Grande do Sul. During the rice growing season, water samples were collected five times, three samples from the river Piratini and four from the São Gonçalo canal. The methodology used for the analysis of residues of quinclorac, carbofuran and clomazone was the High Perfo (more) rmance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and for residues of the pesticides fipronil and betacyfluthrin, the Gas Chromatography with Electron Capture Detection (GC-ECD) was used. Results show that from sowing to harvesting the quantity of pesticide residues in water decreased. It was also observed that, at the lowest point (Laranjal), a greater number of analyses contaminated with residues was detected (11 samples with some type of pesticide). Insecticide carbofuran and herbicide quinclorac were pesticides that presented residues more frequently (16 and 15 times, respectively). Clomazone and fipronil were present in each of the 7 samples with residues and betacyfluthrin was not detected at any site.

A comprehensive multi-residue method for the chromatographic separation and accurate mass identification of 101 pesticides and their degradation products using liquid chromatography/time-of-flight mass spectrometry (LC/TOF-MS) is reported here. Several classes of compounds belonging to different chemical families (triazines, organophosphorous, carbamates, phenylureas, neonicotinoids, etc.) were carefully chosen to cover a wide range of applications in the environmental field. Excellent chromatographic separation was achieved by the use of narrow accurate mass windows (0.05 Da) in a 30 min interval. Accurate mass measurements were always below 2 ppm error for all the pesticides studied. A table compiling the accurate masses for 101 compounds together with the accurate mass of several fragment ions is included. At least the accurate mass for one main fragment ion for each pesticide was obtained to achieve the minimum of identification points according to the 2002/657/EC European Decision, thus fulfilling the EU point system requirement for identification of contaminants in samples. The method was validated with vegetable samples. Calibration curves were linear and covered two orders of magnitude (from 5 to 500 microg/L) for most of the compounds studied. Instrument detection limits (LODs) ranged from 0.04 to 150 microg/kg in green-pepper samples. The methodology was successfully applied to the analysis of vegetable and water samples containing pesticides and their degradation products. This paper serves as a guide for those working in the analytical field of pesticides, as well as a powerful tool for finding non-targets and unknowns in environmental samples that have not been previously included in any of the routine target multi-residue methods. PMID:17996875

Runoff-water samples for the first, third, and fourth quarters of 1975 were analyzed for pesticide residues at LLL and independently by the LFE Environmental Analysis Laboratories. For the compounds analyzed, upper limits to possible contamination were placed conservatively at the low parts-per-billion level. In addition, soil samples were also analyzed. Future work will continue to include quarterly sampling and will be broadened in scope to include quantitative analysis of a larger number of compounds. A study of recovery efficiency is planned. Because of the high backgrounds on soil samples together with the uncertainties introduced by the cleanup procedures, there is little hope of evaluating the distribution of a complex mixture of pesticides among the aqueous and solid phases in a drainage sample. No further sampling of soil from the streambed is therefore contemplated.

The potential of three mass spectrometry (MS) analyzers (triple quadrupole, QqQ; time of flight, TOF; and quadrupole time of flight, QTOF) has been investigated and compared for quantification, confirmation and screening purposes in pesticide residue analysis of fruit and vegetable samples. For this purpose, analytical methodology for multiresidue determination of 11 pesticides, taken as a model, has been developed and validated in nine food matrices for the three mass analyzers coupled to ultra high pressure liquid chromatography. In all cases, limits of quantification around 0.01 mg/kg were reached, fulfilling the most restrictive case of baby-food analysis. Regarding absolute sensitivity, the lower limits of detection were obtained, as expected, for QqQ (100 fg), whereas slightly higher...

Organochlorine pesticides are notorious, due to their high toxicity, persistence in the environment and their tendency to bioaccumulate. Their extensive use in the northwest of Argentina has left residues in the environment. Microbial degradation is an important process for pesticide bioremediation and actinomycetes have a great potential for that. The current study examined organochlorine pesticides in contaminated soil. Indigenous actinomycetes were isolated from contaminated samples to evaluate bacterial growth as well as pesticide removal and release of chloride ions as a result of degradation. Most of the isolated microorganisms belonged to the Streptomyces genus, except one, which belonged to Micromonospora. Bacterial growth depended on the microorganism and the pesticide present (ch...

A rapid method using programmed temperature vaporiser injection-low-pressure gas chromatography-high-resolution time-of-flight mass spectrometry (PTV-LP-GC-HR-TOF-MS) for the analysis of multiple pesticide residues in fruit-based baby food was developed. The fast and inexpensive buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction method and "conventional" approach that employs ethyl acetate extraction followed by gel permeation chromatography (GPC) cleanup were employed for sample preparation. A PTV injector in solvent venting mode was used to reduce volume of acetonitrile and acetic acid (from the buffered QuEChERS extracts) that caused higher column bleed without their elimination. Otherwise, the time-to-digital converter would become saturated in HR-TOF-MS. For fast GC separation allowing analysis of 100 analytes within a 7 min runtime, both a high temperature programming rate and vacuum conditions in a megabore GC column were employed. The use of HR-TOF-MS allowed the unbiased identification and reliable quantification of target analytes through the application of a narrow mass window (0.02 Da) for extracting analyte ions and the availability of full spectral information even at very low levels. With only a few exceptions, the lowest calibration levels for the pesticides tested were pesticide residues in cereal-based foods and baby foods (2003/13/EC). PMID:18164024

To detect pesticide residue on navel orange surface by nondestructive means, five group oranges sprayed water, fenvalerate, isocarbophos, fenpropathrin, carbendazim pesticides respectively were chosen as experimental samples. Laser imaging system was built for acquiring images of fruits. Unitary nonlinear regression function was fitted by analyzing gray histogram curves of images within 12-40 range. The coefficient or eigenvalue of functions was different about every navel orange. The threshold coefficient was confirmed by data processing, which can establish fruits surface sprayed pesticide or not. The result showed that laser imaging technique is feasible for detecting pesticide residue on navel orange surface.

Effects of the maximum field recommended concentration of five pesticides currently used on peaches in Brazil; abamectin, deltamethrin, methoxyfenozide, phosmet and trichlorfon were tested on the predator Chrysoperla carnea (Stephens) (Neuroptera, Chrysopidae). Dimethoate was used as positive standard. Three analytical laboratory tests, based on IOBC?working group pesticides and beneficial organisms guidelines were used: (1) exposure to fresh pesticide residue on glass plates of (a) larvae (susceptible life stage) and (b) adults (less susceptible life stage); (2) direct spraying of eggs and pupae; (3) exposure of larvae and adults to pesticide residues on plant leaves at different intervals after application (persistence). In tests 1, abamectin was slightly harmful to C. carnea larvae and ...

An automated dispersive solid phase extraction (dSPE) cleanup procedure as part of the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method, coupled with liquid chromatography-tandem mass spectrometry using electrospray ionization in positive mode, was used for the simultaneous analysis of 236 pesticides in three dried powdered botanical dietary supplements (ginseng, saw palmetto, and gingko biloba). The procedure involved extraction of the dried powdered botanical samples with salt-out acetonitrile/water extraction using anhydrous magnesium sulfate and sodium chloride, followed by an automated dSPE cleanup using a mixture of octadodecyl- (C(18)) and primary-secondary amine (PSA)-linked silica sorbents and anhydrous MgSO(4) and online LC-MS/MS analysis. Dynamic multiple-reaction monitoring (DMRM) based on the collection of two precursor-to-product ion transitions with their retention time windows was used for all of the targeted pesticides and the internal standard. Matrix-matched calibration standards were used for quantitation, and standard calibration curves showed linearity (r(2) > 0.99) across a concentration range of 0.2-400 ng/mL for the majority of the 236 pesticides evaluated in the three botanical matrices. Mean recoveries (average %RSD, n = 4) were 91 (6), 93 (4), 96 (3), and 99 (3)% for ginseng, 101 (9), 98 (6), 99 (4), and 102 (3)% for gingko biloba, and 100 (9), 98 (6), 96 (4), and 96 (3)% for saw palmetto at fortification concentrations of 25, 100, 250, and 500 ?g/kg, respectively. The geometric mean matrix-dependent instrument detection limits were 0.17, 0.09, and 0.14 ?g/kg on the basis of the studies of 236 pesticides tested in ginseng roots, gingko biloba leaves, and saw palmetto berries, respectively. The method was used to analyze incurred ginseng samples that contained thermally labile pesticides with a concentration range of 2-200 ?g/kg, indicating different classes of pesticides are being applied to these botanicals other than the traditional pesticides that are commonly used and analyzed by gas chromatography techniques. The method demonstrates the use of an automated cleanup procedure and the LC-MS/MS detection of multiple pesticide residues in dried, powdered botanical dietary supplements. PMID:22931171

The use of pesticides on cash crops and exportable food commodities had always been a serious concern. Fruits form one of the important constituents of human diet, in that they give one third of the requirement of calories, vitamins, and minerals. This study has been carried out to determine the level of organochlorine pesticides namely HCH, DDT and Endosulfan in raw fruit nuts. Nuts have proteins and high level of fat content. These properties of nuts attract organochlorine pesticides to accumulate. The analysis of organochlorine pesticide residues in commonly used dry fruits like Cashewnut, Walnut, Coconut, Chilgoza, Chironji, Makhana, Resins, Apricot, Almonds, Date palm, Pistachio nut collected from local market of Lucknow India has indicated presence of very low level of HCH (0.007-1.328 mg kg(-1)), DDT(ND-0.140 mg kg(-1)) and Endosulfan (ND-0.091 mg kg(-1)). There are no MRL values established for nuts in the country. This finding is based on a smaller number of samples, which however suggest that the presence of low level of DDT, HCH and Endosulfan might be due to environmental rather than direct exposure. PMID:21387926

Questions related to test capabilities identified in this document and additional assistance in ...... Pesticide analysis; glyphosate. Carbamates ... Method. Total Suspended Solids. 160.2. TCL-Pesticide/PCBs(P/PCBs) 8081. Total Dissolved ...

Abstract A sensitive and efficient solid-phase microextraction method, based on liquid chromatography and UV-Vis detection, was developed and validated as an alternative method for sample screening prior to LC-MS analysis. It enables the simultaneous determination of ten pesticides in mango fruits. The fiber used was polydimethylsiloxane while optimum SPME conditions employed have been developed and optimized in a previous work. The desorption process was performed in static mode, using acetonitrile as a solvent. The results indicate that the DI-SPME/HPLC/UV-Vis procedure resulted in good linear range, accuracy, precision and sensibility and is adequate for analyzing pesticide residues in mango fruits. The limits of detection (0.6-3.3-g/kg) and quantification (2.0-10.0-g/kg) were achieved ...

Abstract The annual cultivation pattern in the Uma-oya catchment in Sri Lanka is characterized by Yala and Maha rainfall periods and associated cropping. Two cultivation seasons were compared for pesticide residues: base flow, field drainage, and the runoff and supplementary sediment data for three sites in the catchment. Organophosphate and N-methyl carbamate pesticide analysis confirmed a higher concentration in the Yala season with low-flow conditions. Acetylcholinesterase (AChE) activity was measured by standard spectrometry in the brain, muscle, and eye tissues of three freshwater cyprinid fishes, Garra ceylonensis, Devario malabaricus, and Rasbora daniconius from three study sites during months overlapping two seasons in 2010 (December) and 2011 (July). Baseline AChE data were measur...

A rapid and simultaneous method for identification and quantification of pesticides residues in water samples have been developed and applied to the analysis of real samples. Tap and San Francisco River water samples were collected from Propria town and Aracaju city in the state of Sergipe, Brazil. A new single-drop microextraction (SDME) followed by gas chromatography-mass spectrometry techniques were used to determine the dimethoate, methyl parathion, ethion (organophosphates) and permethrin (pyrethroid) pesticides in water samples. The parameters linearity, linear range, precision, accuracy, sensitivity and robustness were studied for validation of the SDME/GC-MS method. An important point to this study is that plots of relative response and logarithmic concentrations were used to verif...

Royal jelly, one of the most important bee products, can be contaminated with pesticide and/or antibiotic residues resulting from treatments applied either inside beehives or in the agricultural environment. A new multiresidue method was developed and validated for analysis of nine pesticides in royal jelly. Solid-phase extraction RP-C18 cartridges were used for sample purification and isolation of analytes. Final solution was analyzed with GC and micro-electron-capture detection. Four synthetic acaricides used by beekeepers (bromopropylate, coumaphos, malathion and t-fluvalinate), and moreover one pyrethroid, two organochlorine, and two organophosphate insecticides were tested. Linearity is demonstrated for the range of 0.0025-1mgkg-1, with correlation coefficients ranging from 0.99991 to...

Three alkylpolyoxyethylene surfactants bearing the same hydrophobic chain and a different number of oxyethylene groups were investigated as suitable candidates for the soil washing treatment of contaminated soil samples containing bentazone. Comparable good recoveries of the pesticide were obtained working with these surfactants. The photocatalytic treatment of the collected washing wastes, performed in the presence of suspended TiO(2) particles under irradiation with simulated sunlight, leads to the effective degradation of bentazone residues after a time depending on the nature and concentration of the chosen amphiphile. Brij 35 was found to be the best surfactant candidate, giving the faster abatement of the pesticide in the collected wastes. The overall treatment time depends on the bentazone mineralization kinetics, markedly slow in the presence of surfactants. Useful information about the photocatalytic degradation route was obtained from the HPLC-MS analysis of transient intermediates formed in water. PMID:22036015

Exposure to pesticide residues in dietary sources is a major concern of Europeans. Meanwhile, drinking water and food safety authorities establish and implement maximum residue levels (MRLs) for pesticides in drinking water and food. This study compares MRLs between EU, US and Codex authorities for both drinking water and other beverages, i.e. milk, juice and wine, investigating differences between authorites as well as between beverage types. These results were confronted with public perceptions towards pesticide residues in beverages, based on a consumer survey conducted in Copenhagen, Denmark. Seven frequently-occurring pesticides were selected for this study. Results show that since no specific MRLs for juice and wine exist, MRLs for the raw products were used instead. Furthermore, established MRLs are significantly greater for pesticides in beverages when compared to legal standards for drinking water. Maximum levels in drinking water, if available, are generally low (0.0001 mg/L in the EU), while MRLs for pesticides in milk, juice and wine range from 0.05 to 60 mg/L. At the same time, questionnaire participants were equally concerned about their exposure to pesticide residues in drinking water and other beverage types. These findings reveal some inconsistencies in setting legal maximum concentrations for pesticide residues in different dietary sources as well as between different drinking water and food safety authorities.

The potential of three mass spectrometry (MS) analyzers (triple quadrupole, QqQ; time of flight, TOF; and quadrupole time of flight, QTOF) has been investigated and compared for quantification, confirmation and screening purposes in pesticide residue analysis of fruit and vegetable samples. For this purpose, analytical methodology for multiresidue determination of 11 pesticides, taken as a model, has been developed and validated in nine food matrices for the three mass analyzers coupled to ultra high pressure liquid chromatography. In all cases, limits of quantification around 0.01 mg/kg were reached, fulfilling the most restrictive case of baby-food analysis. Regarding absolute sensitivity, the lower limits of detection were obtained, as expected, for QqQ (100 fg), whereas slightly higher limits (300 fg) were obtained for both TOF and QTOF. Confirmative capacity of each analyzer was studied for each analyte based on the identification points (IPs) criterion, useful for a comprehensive comparison. QTOF mass analyzer showed the highest confirmatory capacity, although QqQ normally led to sufficient number of IPs, even at lower concentration levels. The potential of TOF MS was also investigated for screening purposes. To this aim, around 50 commercial fruits and vegetables samples were analyzed, searching for more than 400 pesticides. TOF MS proved to be an attractive analytical tool for rapid detection and reliable identification of a large number of pesticides thanks to the full spectrum acquisition at accurate mass with satisfactory sensitivity. This process is readily boosted when combined with specialized software packages, together with theoretical exact mass databases. Several pesticides (e.g. carbendazim in citrus and indoxacarb in grape) were detected in the samples. Further unequivocal confirmation of the identity was performed using reference standards and/or QTOF MS/MS experiments. PMID:20301091

Efficient clean-up is indispensable for preventing matrix effects in multi-residue analysis of pesticides in food by liquid and gas chromatography (LC and GC) coupled to mass spectrometry (MS). High-throughput planar solid phase extraction (HTpSPE) was recently introduced as a new clean-up concept in residue analysis of pesticides in fruit and vegetables (C. Oellig, W. Schwack, 2011 [45]). Thin-layer chromatography (TLC) was used to completely separate pesticides from matrix compounds and to focus them into a sharp zone, followed by extraction of the target zone by the TLC-MS interface. As rather challenging matrices, tea samples were chosen in this study. Besides chlorophylls and polyphenols, high amount of caffeine is co-extracted resulting in strong matrix effects both in LC-MS and GC-MS. The former HTpSPE procedure was adapted to initial extracts of green and black tea resulting in colorless extracts nearly free of matrix effects and interferences, as shown for seven chemically representative pesticides (acetamiprid, penconazole, azoxystrobin, chlorpyrifos, pirimicarb, fenarimol, and mepanipyrim). LC-MS/MS calibration curves obtained in the range of 0.002-0.5mg/kg from matrix-matched standards and solvent standards were nearly identical and demonstrated the effectiveness of clean-up by HTpSPE. Mean recoveries determined by LC-MS/MS against solvent standards at spiking levels of 0.01 and 0.1mg/kg ranged between 72 and 114% with relative standard deviations (RSDs) of 0.7-4.7% (n=4), while LC-MS measurements of tea samples spiked at 1mg/kg provided recoveries of 81-104% with RSDs of 1.2-4.9% (n=6). Using LC-MS/MS, the method showed high sensitivity with signal-to-noise ratios >10 for concentrations below 0.002mg/kg. HTpSPE of one sample was done in a few minutes, while numerous samples were cleaned in parallel at minimal costs with very low sample and solvent consumption. PMID:22981507

The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides' residual persistence, the predator was exposed for 3d to pesticide residues on tomato sprouts that had been treated 1 h, 7 d or 14 d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (E(x)) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14 d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7 d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus. PMID:22342338

This purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year 1990. The ACL has four technical groups -- Chemical Analysis, Instrumental Analysis, Organic Analysis, and Environmental Analysis. The Chemical Analysis Group uses wet-chemical and instrumental methods for elemental, compositional, and isotopic analyses of solid, liquid, and gaseous samples and provides specialized analytical services. The Instrumental Analysis Group uses nuclear counting techniques in radiochemical analyses over a wide range of sample types from low-level environmental samples to samples of high radioactivity. The Organic Analysis Group uses a number of complementary techniques to separate and to quantitatively and qualitatively analyze complex organic mixtures and compounds at the trace level, including synthetic fuels, toxic substances, fossil-fuel residues and emissions, pollutants, biologically active compounds, pesticides, and drugs. The Environmental Analysis Group performs analyses of inorganic environmental and hazardous waste and coal samples.

The goal of this study was to expand knowledge on the performance of screening methods based on accurate mass measurements using a liquid chromatography electrospray quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) system operating in full scan mode and with automatic identification based on the use accurate-mass databases. The study involved the analysis of 97 pesticides, in five matrices (tomato, pepper, zucchini, orange and leek) and at three concentration levels (20, 50 and 100 ?g kg(-1)). Aspects concerning optimization of the search parameters, sensitivity, matrix effects, efficiency of the algorithm search, usefulness of fragment ions, etc., are evaluated in deep. Sensitivity requirements have been identified as the main obstacle affecting the automatic identification of pesticides, especially in complex matrices, where the ionization suppression reduces the detectability of analytes. In addition, we have detected some failures in the software used for automatic data processing in terms of analysis of isobaric compounds, use of isotopic clusters, spectral deconvolution and data processing speed that hamper the correct identification in some pesticide/matrix combinations. These drawbacks should be improved in the future for its effective implementation in routine residue analysis. PMID:21798548

This article presents a novel application of carbon nanotubes for the determination of pesticides (chlortoluron, diuron, atrazine, simazine, terbuthylazin-desethyl, dimetoathe, malathion and parathion) in virgin olive oil samples. For this purpose, two carbon nanotubes, multi-walled and carboxylated single-walled, were evaluated, the later being the most appropriate for the aim of the work. The sorbent (30 mg) was packed in 3-mL commercial cartridge and the virgin olive oil samples diluted (20%, v/v) in hexane were passed through it. After a washing step with 3 mL of hexane to remove the sample matrix, the pesticides were eluted with 500 microL of ethyl acetate. In order to achieve lower detection limits, the eluent was evaporated under a nitrogen stream and the residue reconstituted in 50 microL of the same solvent. Aliquots of 2 microL of the extract were directly injected into the GC-MS system for analysis. The low limits of detection achieved, between 1.5 and 3.0 microg L(-1), permit the application of the method to control the presence of these pollutants in very restrictive samples such as the ecological virgin olive oil. In addition to the sensitivity enhancement, the solid-phase extraction procedure is rather simple as it involves a single preconcentration-elution step, which allows sample processing in less than 8 min. Moreover, the cartridge can be reused at least 100 times without losing performance. The method was applied to the determination of the pesticides in two monovarietal and one ecologic commercial extra virgin olive oil samples. Two pesticides were detected in each of the monovarietal virgin olive oils while the ecological sample resulted to be a pesticide-free one. PMID:19298965

Abstract in portuguese O presente trabalho tem como objetivo aplicar uma metodologia multiresíduo visando a determinação de pesticidas em frutas e vegetais, utilizando extração com fluido supercrítico e análise por cromatografia gasosa e detector por captura de elétrons e espectrometria de massas. Um método convencional por extração sólido-líquido baseado na literatura e um método com fluido supercrítico desenvolvido, foram aplicados na determinação simultânea de 32 pesticidas (more) de 4 classes diferentes (organoclorados, organonitrogenados, organofosforados e piretróides) em amostras de alface, batata, maçã e tomate. As recuperações obtidas para a maioria dos pesticidas foram de 74% a 96% para ambos os métodos em níveis entre 0,04 - 0,10 mg kg-1, os limites de quantificação (dependendo da matriz e do pesticida) foram menores que 0,01 mg kg-1. SFE mostrou-se vantajosa quando comparada à extração sólido-líquido como economia de solventes, tempo e custos, podendo ser aplicada no monitoramento de pesticidas em alimentos. Abstract in english The aim of this paper was to apply a multiresidue method using Supercritical Fluid Extraction (SFE) and capillary gas chromatography with electron capture and mass spectrometry detections in the analysis of the levels of pesticide residues in fruits and vegetables. Single laboratory validation of both solid-liquid and supercritical fluid extraction methods was carried out for 32 compounds selected from four pesticide classes (organochlorine, organonitrogen, organophosphor (more) us and pyretroid) in blank and fortified samples of fresh lettuce, potato, apple and tomato. Recoveries for the majority of pesticides from fortified samples at fortification level of 0.04-0.10 mg kg-1 ranged 74-96% for both methods and confirmation of pesticide identity was performed by gas-chromatography-mass spectrometry in a selected-ion monitoring mode. Both methods showed good limits of detection (less 0.01 mg kg-1, depending on the pesticide and matrix) and the SFE method minimized environmental concerns, time, and laboratory work.

This chapter describes a simple, fast, and inexpensive method for the determination of pesticides in foods and potentially other matrices. The method, known as the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for pesticide residues involves the extraction of the sample with ace...

Agricultural practices generally require the use of pesticides by olive growers for the best olive and olive oil production. Thus, analytical methods are needed to identify and quantify the pesticide residues that may be present, and ensure that the product complies with regulatory requirements. I...

Tea industry is one of the most important agro-industry of the country. Wide scale use of pesticides in tea cultivation to protect the crops from insect and fungus has led to buildup of their residues in several parts of tea plant, and around the area. Some of the pesticides are toxic and injurious ...

Oxidative destruction of pesticides with ozone has significant potential as a treatment technology. Complete removal and or substantial reduction of pesticide residues in raw drinking water, wastewater, soil, and on surfaces of fruits and vegetables have been reported; however, predicting the extent...

Probabilistic techniques were used to characterize dietary exposure of consumers to pesticides found in twelve commodities implicated as having the greatest potential for pesticide residue contamination by a United States-based environmental advocacy group. Estimates of exposures were derived for t...

For Healthy Kids focuses on preventing children's exposure to pesticides by educating agricultural workers on preventing "the take home pathway" for pesticide residue. A baseline survey encompassing over 570 households in the Yakima valley was conducted in the summer of 1999. Ho...

The Kenaga nomogram is a simple device developed by the U.S. Environmental Protection Agency (EPA) in the early 1980s and is currently used to predict the maximum potential pesticide residue levels in the food chain of wildlife before pesticide registration. o evaluate the accura...

Chemical residues, such as insecticides and anthelmintics, are frequently redistributed from the aquatic environment to marine species. This work reports on a fast validated protocol for the analysis of azamethiphos, three avermectins, two carbamates and two benzoylurea pesticides and chemotherapeutic agents in seaweeds based on pressurized liquid extraction and separation of analytes by liquid chromatography coupled with tandem mass spectrometry. The variables affecting the efficiency of pressurized liquid extraction, including temperature, number of extraction cycles, static extraction time and percent acetonitrile flush volume, were studied using a Doehlert design. The optimum parameters were 100??C and one cycle of 3?min with 70?% acetonitrile. Adequate in-cell clean-up of the seaweeds...

Abstract in english ELISAs have been applied to pesticide residue analysis due to their high sensitivity and selectivity. However, some ELISAs performance may be affected by matrix components. In this work, ELISA for carbaryl in water samples was checked for interference by naturally occurring fulvic acids. The results suggested that the high fulvic acid concentration (?³30 mg L-1) and acidic pH conditions (pH 4.0) interfere with the signal detection decrea (more) sing the method sensitivity. A dilution of the samples and adjust to pH 8.0 are appropriate to minimize the matrix interferences in the ELISA method. Good correlation between ELISA and HPLC-DAD results was observed.

In this study, tobacco leaf samples (n?=?26) were collected from different areas in Kushtia to determine the presence of residues of cypermethrin, diazinon, heptachlor, methoxychlor dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethan (DDD) and dichlorodiphenyldichloroethylene (DDE). The analysis was conducted by a High Performance Liquid Chromatography (HPLC) system that was equipped with a photodiode array detector. Both cypermethrin and diazinon were detected in tobacco samples from six districts, namely, Mirzapur, Shahebnagar, Kodalipara, Pragpur, Farakpur and Taragunia. The highest concentration of cypermethrin was found in Kodalipara (2.00?ppm) while the highest concentration of diazinon was detected in a sample from Pragpur (0.15?ppm). The pesticide DDT was only dete...

Tea is considered as a ?health beverage? due its antioxidant properties and resultant beneficial effects on human health. Such a beverage should be free from toxic elements such as pesticide residues and heavy metals. A large scale survey of teas produced in the tea factories of south India had been carried out for a period of three years from 2006 to 2008 and 912 tea samples were analysed for the residues of certain pesticides such as dicofol, ethion, quinalphos, hexaconazole, fenpropathrin, fenvalerate and propargite which are used for pest and disease control in tea in this part of the country. The analytical data proved that only less than 0.5 percentage of tea samples had residues of these pesticides. However, residues of pesticides were below their maximum limits in tea, stipulated b...

The Dietary Risk Evaluation System (DRES) estimates exposure to pesticides in the diet by combining information concerning residues on raw agricultural commodities with information on consumption of those commodities. It then compares the estimated exposure level to a toxicologi...

To quantify the effect of household and industrial processing on the pesticide residues, carrots (Daucus carota) were sprayed during cultivation with three fungicides (boscalid, difenoconazole and tebuconazole), two insecticides (chlorpyrifos and dimethoate) and one herbicide (linuron). The most con...

...Thiamethoxam is a member of the neonicotinoid class of pesticides and...as a metabolite, another neonicotinoid, clothianidin. Structural...in thyroid colloid with imidacloprid). Thus, EPA has not...Tolerance for Residues of the Insecticide Resulting from...

...tolerances for residues of the insecticide clothianidin, (E...similar to effects from other neonicotinoid insecticides. In subchronic oral...Clothianidin is a member of the neonicotinoid class of pesticides and...

To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for...

This is an introductory article to a special section of the Journal of Agricultural and Food Chemistry consisting of publications from the 47th Annual Florida Pesticide Residue Workshop held in St. Pete Beach, FL in July of 2010....

...the Department of Health and Human Services are the Federal agencies...veterinary drugs, pesticides, hormones, and environmental contaminants...or a flock (for example, growth promotants or antibiotics given...It only works for microbial growth-inhibiting residues...

...of drinking water concentrations were directly entered...assessment, the water concentration value of 4.429 ppb...assessment, the water concentration of value 1.5 ppb...effects of a particular pesticide's residues and...completeness of the database on toxicity and...

Instrumental methods are essential in the determination of organic compounds and in the analysis of environmental samples for the presence and distribution of organics. Literature reviews on analytical methods for pesticides and for water analysis were presented. Conference proceedings on dioxins and related compounds provided information on analytical methods, sources, transport and fate, control technology, toxicology, and other topics. Pattinson and Wilkins investigated crimp-cap vial closures for possible contamination in pesticide residue analyses. Nine types of vial closures were studied and characterized after solvent extraction. They concluded that ethylenethiourea and diphenylamine may be contaminants associated with certain vial closures. Van Der Greef et al. focused on liquid chromatograph (LC)-mass spectrometry methodology and on optimizing the entire methodology, including improving the LC compatibility, interface technology, detectability, and pre- and post-column derivitization techniques. Scott reported on a software expert system for classification and identification of mass spectra of toxic compounds. The rule-building expert system showed more accuracy in identification of unknwon spectra using ternary-encoded spectra compared to binary-encoded spectra. The program was effective in spectral classification and identification problems. The literature summarized in this review addressed analytical methods or the presence and behavior of compounds in the environment. Total organic determinations are presented, followed by surfactants, aliphatic and aromatic hydrocarbons, pesticides, chlorinated hydrocarbons, and related compounds; naturally occurring organics; and organics in surface and groundwater, drinking water, and wastewater; and hazardous wastes are presented in tables 1 through 9.

We evaluated the exposure to pesticides from the consumption of passion fruits and subsequent human health risks by combining several methods: (i) experimental field studies including the determination of pesticide residues in/on passion fruits, (ii) dynamic plant uptake modelling, and (iii) human health risk assessment concepts. Eight commonly used pesticides were applied onto passion fruits cultivated in Colombia. Pesticide concentrations were measured periodically (between application and harvest) in whole fruits and fruit pulp. Measured concentrations were compared with predicted residues calculated with a dynamic and crop-specific pesticide uptake model, namely dynamiCROP. The model accounts for the time between pesticide application and harvest, the time between harvest and consumption, the amount of spray deposition on plant surfaces, uptake processes, dilution due to crop growth, degradation in plant components, and reduction due to food processing (peeling). Measured and modelled residues correspond well (r(2)=0.88-0.99), with all predictions falling within the 90% confidence interval of the measured values. A mean error of 43% over all studied pesticides was observed between model estimates and measurements. The fraction of pesticide applied during cultivation that is eventually ingested by humans is on average 10(-4)-10(-6), depending on the time period between application and ingestion and the processing step considered. Model calculations and intake fractions via fruit consumption based on experimental data corresponded well for all pesticides with a deviation of less than a factor of 2. Pesticide residues in fruits measured at recommended harvest dates were all below European Maximum Residue Limits (MRLs) and therefore do not indicate any violation of international regulatory thresholds. PMID:22673401

Aquatic environments get contaminated with pesticides residues that result from the application of pesticides in agricultural practices. The present study aimed to evaluate the pesticides Malathion and Deltamethrin on biological and biochemical parameters of Helisoma duryi snails. The results showed that LC10 of the two pesticides caused considerable reduction in survival rates and egg production of treated snails. Glucose concentration in hemolymph of the exposed snails showed a significant increase. On the other hand, albumin in hemolymph and glycogen contents as well as the activities of enzymes in tissues of snails including lactate dehydrogenase (LDH), succinate dehydrogenase (SDH), arginase, and ornithine aminotransferase (OAT) were significantly inhibited. Meanwhile, the activity of...

In this study, a rapid, specific and sensitive multi-residue method based on acetonitrile extraction followed by dispersive solid-phase extraction (d-SPE) clean-up was implemented and validated for multi-class pesticide residues determination in palm oil for the first time. Liquid-liquid extraction followed by low-temperature precipitation procedure was evaluated in order to study the freezing-out clean-up efficiency to obtain high recovery yield and low co-extract fat residue in the final extract. For clean-up step, d-SPE was carried out using a combination of anhydrous magnesium sulphate (MgSO(4)), primary secondary amine, octadecyl (C(18)) and graphitized carbon black. Recovery study was performed at two concentration levels (10 and 100 ng g(-1)), yielding recovery rates between 74.52% and 97.1% with relative standard deviation values below 10% (n?=?6) except diuron. Detection and quantification limits were lower than 5 and 9 ng g(-1), respectively. In addition, soft matrix effects (?±20%) were observed for most of the studied pesticides except malathion that indicated medium (20-50%) matrix effects. The proposed method was successfully applied to the analysis of suspected palm oil samples. PMID:21989900

A new multi-residue methodology using liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS) for the quantitative analysis of pesticides has been developed. The analytical performance of the method was evaluated by screening herbicide and insecticide residues in 10 kinds of imported soybeans. The accurate mass was obtained in different spiking levels (from 0.05 to 0.10 mg/kg) and the accuracy error was lower than 3 x 10(-6), which is well within the accepted limits for target confirmation. The linearity of response ranged from 0.03 mg/kg to 1.0 mg/kg and the correlation coefficient was greater than 0.99. The average recoveries of herbicides and insecticides ranged from 60% to 120% of the fortified herbicides and insecticides in soybeans at 0.05 - 0.10 mg/kg levels for the majority of herbicides and insecticides, and the relative standard deviations (RSD) were between 2.17% and 13.54%. The limits of detection (LOD) were between 0.002 and 0.026 mg/kg. The results indicated that the method developed is easier, faster, and more sensitive. It also demonstrated that this method can meet the requirements for simultaneous determination of herbicides and insecticides in soybeans. This study provides valuable evidence for that LC-TOF-MS method has the potential in screening multi pesticide residues in soybeans. PMID:18257315

A liquid chromatographic (LC) method using UV detection at 233 nm was used to study the degradation of methomyl in tomatoes and green beans grown in greenhouses. A liquid-liquid extraction with CH2Cl2-methanol (90 + 10, v/v) and a cleanup step with Florisil were combined with LC to isolate, recover, and quantitate the pesticide. Average recoveries obtained at spike levels of 0.03 and 0.40 mg/kg were 83.2-84.7% for tomatoes and 83.3-87.5% for green beans. Determination limits were 0.03 mg/kg for tomatoes and 0.01 mg/kg for green beans. Levels of methomyl residues were studied in tomatoes and green beans grown in an experimental greenhouse to establish the effect of the kind of greenhouse, application dose, species grown, and climatic conditions on the degradation of this pesticide. Analysis of variance showed that doses did not affect the response. The half-life, however, is greater in a flat-roof greenhouse than in an asymmetric-roof greenhouse and is significantly longer for green beans than for tomatoes and longer in winter than in spring. A preharvest time of about 5 days may be suitable for green beans sprayed with methomyl. Tomatoes show residue levels at the time of application lower than Spanish minimum residue levels. PMID:9170659

Determinations of organochlorine pesticides and similar chemical residues in blood serum have often reported detection limits of 1 ng/mL. When a study group has incurred body burdens lower than this, underestimates and misclassifications of exposure may occur because persons with pesticide residue concentration below the limit of detection are usually treated as zeros.' Thus in order to more accurately assess exposures in such populations, analysis of adipose tissue has been done. Recently, with TCDD, use of a sufficient volume of serum, as much as 0.5 L, in conjunction with appropriate analytical techniques has been shown to achieve detection limits necessary for epidemiological assessments, i.e., comparable to analysis of adipose tissue. In a population-based study involving children in which the authors were involved, it was not feasible to obtain specimens of either adipose or a large volume of serum. There was no compelling health motivation for such measures, nor did they wish to impair participation rates. Therefore, they chose to optimize the existing serum analysis, in order to achieve a detection limit low enough to assess reasonably the anticipated exposures.

A proficiency test on incurred and spiked pesticide residues in wheat was organised in 2008. The test material was grown in 2007 and treated in the field with 14 pesticides formulations containing the active substances, alpha-cypermethrin, bifentrin, carbendazim, chlormequat, chlorpyrifos-methyl, difenconazole, epoxiconazole, glyphosate, iprodione, malathion, pirimicarb, prochloraz, spiroxamin and trifloxystrobin. After harvest, the test material was additionally spiked in the laboratory with three pesticides, that where the residues were too low, and axozystrobin. In total, 72 laboratories submitted results and z-scores were calculated for all laboratories and pesticides, except for glyphosate where only five laboratories submitted results and summed weighted z-scores were calculated for the laboratories with a sufficient scope. For several pesticides, the submitted results were strongly depending on the extraction procedure and consequently the assigned values were calculated based on part of the results. Acceptable z-scores were obtained by 56-97% of the participants.

The present study has been carried out to evaluate the organochlorine pesticide contamination in wheat from Konya region. This region is the largest area of cereal production in Turkey. The contamination level has been determined according to the European Community Directives. Different wheat samples (36) were obtained from local farmers and wheat factories in this region. All the wheat samples examined were found to be contaminated by organochlorine pesticide residues of cis-Chlordane and methoxychlor. Chlordane isomers, methoxychlor, DDT and its metabolites, aldrin, beta HCH, heptachlor and lindane have been found to be the highest organochlorine pesticide residues. In some of these samples, various organochlorine pesticide residues have been determined to be higher than European Community maximum residual limits. The residues of aldrin in one sample, trans-Chlordane in one sample, oxy-chlordane in eight samples and methoxychlor in one sample were found to be in excess of EC MRLs. Since most of the samples have been found to be contaminated with residues and some residues exceed EC MRLs, a control of organochlorine pesticide residues in wheat is necessary. PMID:20156519

Background: Few data exist in Latin America concerning the association between organophosphate (OP) urinary metabolites and the consumption of fruits and vegetables and other exposure risk variables in schoolchildren. Methods: We collected samples of urine from 190 Chilean children aged 6-12years, fruits and vegetables, water and soil from schools and homes, and sociodemographic data through a questionnaire. We measured urinary dialkylphosphate (DAP) OP metabolites and OP pesticide residues in food consumed by these 190 children during two seasons: December 2010 (summer) and May 2011 (fall). We analyzed the relationship between urinary DAP concentrations and pesticide residues in food, home pesticide use, and residential location. Results: Diethylalkylphosphates (DEAP) and dimethylalkylpho...

Distribution of pesticide non extractable residues resulted from the incubation of two natural soils with each of the isoproturon, diazinon and cypermethrin pesticide was assessed in this study. Pesticide non extractable residues distribution in soil physical and chemical fractions is known to ultimately affect their fate. This study aimed to address the fate and behaviour of the non extractable residues in the context of their association with soil physical and chemical fractions with varying properties and characteristics. Non extractable residues were formed from incubation of each pesticide in the two natural soils over a period of 24 months. Soils containing the non extractable residues were fractionated into three solid phase fractions using a physical fractionation procedure as follows: Sediment (SED, >20 ?m), (II) Microaggregate (MA, 20-2 ?m) and (III) Colloid phase (COL, 2-0.05 ?m). Each soil fraction was then fractionated into organic carbon chemical fractionations as follows: Fulvic acid (FA), Humic acid (HA) and Humin (HM). Significant amount of the pesticides was lost during the incubation period. Enrichment factors for the organic carbon and the 14C-pesticide residues were higher in the MA and COL fraction rather than the SED fraction. Greater association and enrichment of the fulvic acid fraction of the organic carbon in the soil was observed. Non extractable residues at the FA fraction showed to diminish while in the HA fraction were increased with decreasing the fraction size. An appreciable amount of non extractable residues were located in the HM fraction but this was less than the amount recovered in the humic substances. Long term fate of pesticide non extractable residues in the soil structural components is important in order to assess any risk associated with them.

Litchi is a famous tropical and subtropical fruit originated in South China. Guangdong is one of the most important litchi production areas in China. Two hundred and eight soil samples were collected in litchi orchards after harvesting the fruit, in which nine often-used pesticides including metalaxyl, mancozeb, carbendazim, deltamethrin, cypermethrin, cyhalothrin, dipterex, dimethoate and dichlorvos were detected. The results showed that the detectable rates of various pesticides were ranked cypermethrin (59.1%) > carbendazim (51.0%) > mancozeb (11.1%) > metalaxyl (6.7%) > cyhalothrin (3.4%). Dimethoate and dichlorvos were detectable in few soil samples, and deltamethrin and dipterex were undetectable in all samples. The percentages of soil samples where different pesticides could be detected in one sample followed the order: one pesticide detectable (40.4%) > two pesticides simultaneously detectable (31.3%) > pesticide undetectable (18.8%) > three pesticides simultaneously detectable (8.2%) > four pesticides simultaneously detectable (1.4%). The concentrations of mancozeb in detectable samples averaged 39.05 microg x kg(-1), and that of cypermethrin was 7.83 microg x kg(-1). The mean concentrations of the other five pesticides ranged from 0.19 microg x kg(-1) to 1.65 microg x kg(-1). Totally, the pesticide residue status in litchi orchards in Guangdong was venial. PMID:21250457

Imazalil, cypermethrin and carbendazim are detected in plants for human nutrition. To explore whether their combinations, applied orally in low doses, would induce changes in metabolic patterns and hepatotoxicity, a subchronic in vivo experiment was conducted. Doses of 10mg/kg of imazalil (im) and cypermethrin (cy) and 20 mg/kg of carbendazim (car) and their combinations (im, 10 mg/kg+cy, 10mg/kg; im, 10mg/kg+car, 20mg/kg; car, 20 mg/kg + im, 10 mg/kg) were given to Swiss mice daily over 28 days. After 24 hr from the last dose, the relationships of cytotoxicity biomarkers were analysed: serum lactate dehydrogenase, aspartate transaminase, alanine transferase, amylase, alkaline phosphatase, creatine kinase, creatinine and total proteins. Individual pesticides showed different toxic potential (cy>im car) generally characterized by increase in enzyme activities. Histological analysis showed that cypermethrin, but not imazalil or carbendazim, alone can cause mild necrosis. Combinations generally caused decrease in the activity of enzymes, indicating liver damage. Low doses of carbendazim in combination with low doses of imazalil or cypermethrin caused very pronounced hepatic necrosis, more than any of the three individually applied pesticides or combination of imazalil and cypermethrin. In fruits and vegetables for human consumption, residues of these three pesticides and prolonged combined intake of low doses, which by themselves acutely would not cause any effect, may have similar hepatotoxic effects. PMID:22077925

A collaborative study was conducted to determine multiple pesticide residues in fruits and vegetables using a quick, simple, inexpensive, and effective sample preparation method followed by concurrent analysis with gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/ tandem mass spectrometry (LC/MS/MS). For short, the method is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged, and safe. Twenty representative pesticides were fortified in 3 matrixes (grapes, lettuces, and oranges) at 3 duplicate levels unknown to the collaborators ranging from 10 to 1000 ng/g. Additionally, 8 incurred pesticide residues were determined. Thirteen laboratories from 7 countries provided results in the study, and a variety of different instruments were used by collaborators. The QuEChERS procedure simply entails 3 main steps: (1) a 15 g homogenized sample is weighed into a 50 mL centrifuge tube to which 15 mL acetonitrile containing 1% HOAc is added along with 6 g MgSO4 and 1.5 g NaOAc, and the tube is shaken and centrifuged; (2) a portion of the extract is mixed with 3 + 1 (w/w) MgSO4-primary secondary amine sorbent (200 mg/mL extract) and centrifuged; and (3) the final extract is analyzed by GC/MS and LC/MS/MS. To detect residues kresoxim-methyl (9.2 +/- 3.2 ng/g) and cyprodinil (112 +/- 18) were found in the grapes; permethrins (112 +/- 41), lamda-cyhalothrin (58 +/- 11), and imidacloprid (12 +/- 2) were determined in the lettuces; and ethion (198 +/- 36), thiabendazole (53 +/- 8), and imazalil (13 +/- 4) were determined in the oranges. Chlorpyrifosmethyl (200 ng/g) was used as a quality control standard added during sample homogenization and yielded 86% recovery and 19% RSD(R). Intralaboratory repeatabilities for the method averaged 9.8% RSD for all analytes. The results demonstrate that the method is fit-for-purpose to monitor many pesticide residues in fruits and vegetables, and the Study Director recommends that it be adopted Official First Action. PMID:17474521

The fate of the 14C-labeled herbicides ethidimuron (ETD), methabenzthiazuron (MBT), and the fungicide anilazine (ANI) in soils was evaluated after long-term aging (9-17 years) in field based lysimeters subject to crop rotation. Analysis of residual 14C activity in the soils revealed 19% (ETD soil; 0-10 cm depth), 35% (MBT soil; 0-30), and 43% (ANI soil; 0-30) of the total initially applied. Accelerated solvent extraction yielded 90% (ETD soil), 26% (MBT soil), and 41% (ANI soil) of residual pesticide 14C activity in the samples. LC-MS/MS analysis revealed the parent compounds ETD and MBT, accounting for 3% and 2% of applied active ingredient in the soil layer, as well as dihydroxy-anilazine as the primary ANI metabolite. The results for ETD and MBT were matching with values obtained from samples of a 12 year old field plot experiment. The data demonstrate the long-term persistence of these pesticides in soils based on outdoor trials. PMID:22591787

Human intake of pesticide residues from consumption of processed food plays an important role for evaluating current agricultural practice. We take advantage of latest developments in crop-specific plant uptake modeling and propose an innovative dynamic model to estimate pesticide residues in the wheat-environment system, dynamiCROP. We used this model to analyze uptake and translocation of pesticides in wheat after foliar spray application and subsequent intake fractions by humans. Based on the evolution of residues in edible parts of harvested wheat we predict that between 22mg and 2.1g per kg applied pesticide are taken in by humans via consumption of processed wheat products. Model results were compared with experimentally derived concentrations in wheat ears and with estimated intake ...

Honey, being a natural product manufactured by honey bees is considered to be free from any extraneous material. The over-reliance on pesticides caused several environmental problems including pesticide residues in food. This constitutes a potential risk for human health, because of their sub acute and chronic toxicity. Therefore this study was carried out to know the extent of pesticide residue in honey produced in the various parts of Himachal Pradesh. Among different pesticides analysed in honey; HCH and its isomers were the most frequently detected followed by DDT and its isomers. Of the studied synthetic pyrethroids, only cypermethrin was found in honey samples. Residues of organophosphates viz. acephate, chlorpyriphos, ethion and monocrotophos were not detected, however malathion?s r...

Pesticide concentrations in fish were lower than recommended for human consumption. - Organochlorine pesticides (p,p'-DDT, p,p'-DDD, p,p'-DDE, aldrin, lindane, and heptachlor) were measured in muscle tissue of catfish (Tachysurus thalassinus) during the dry and wet season. Catfish were collected from the South Patches of the Bay of Bengal during October-December 1997 and May-July 1998. Tissue residues were analyzed by using gas-chromatography (GC) in electron capture detector (ECD) mode and were verified by thin layer chromatography (TLC). The pesticide residues levels were found in order of {sigma} DDT>Heptachlor>Lindane>Aldrin. Higher levels of pesticide residues were found in all samples during dry season, as compared with the wet season, primarily due to elevated lipid content in fishes. A positive correlation and linear relationship was observed between the pesticide residues ({sigma}DDT and {sigma}OCs) and lipid content of fishes. However, the concentrations of pesticide residues in the muscle were found to be lower than the FAO/WHO [(1993) Food standards programme. Codex Alimentarius Commission, vol. 9 (4) pp. 149-158] recommended permissible limit for human consumption.

This review presents with selected examples the versatility of nuclear magnetic resonance (NMR) spectroscopy in the analysis of toxic organophosphorus (OP) compounds, i.e. OP pesticides and chemical warfare agents (CWAs). Several NMR applications of biological importance, like studies on inhibition mechanism, metabolism, and exposure determination, are presented. The review also concerns with the environmental analysis of OP compounds by NMR spectroscopy. Residue analysis of environment and food samples as well as characterization of degradation in environment is discussed. Some of the NMR studies that have been done to support the Chemical Weapons Convention, i.e. the development of suitable CWA detoxification means and the method development of verification analysis for CWAs and their de...