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Processing Factors (PFs) reflect the concentration or dilution of pesticide residues resulting from food processing. PFs are key elements to demonstrate the compliance of processed foods with Maximum residue levels (MRLs) as set by Regulation 396/2005. While efforts have been made by the European Food Safety Authority (EFSA) and by national authorities to compile PFs from processing studies, such PFs are not available for all pesticides/processed product combinations. The EU vegetable oil and proteinmeal industry association (FEDIOL) has therefore developed a theoretical approach to approximate MRLs in crude vegetable oils and fats, based on the partition coefficient (log Pow) of the pesticides and on the oil content of the raw materials. To substantiate this approach, a pilot-scale processing study was initiated with rapeseeds spiked with selected pesticides and the experimental PFs for these pesticides determined. The aims of this study were (i) to study the reliability of pilot-scale conditions for PF determination and (ii) to assess the experimental PFs obtained in comparison to the theoretical PFs proposed by FEDIOL. This study demonstrated that production yields obtained for crude oil and meal in this processing study are similar to those in industrial processes even if differences were observed in the individual production steps (mechanical or solvent extraction steps). The experimental PFs obtained confirmed that the chosen fat-soluble pesticides did concentrate in the oil fraction. For metalaxyl-M having a log Pow lower than 3, a partitioning between the oil and the meal was observed, as expected. By comparing the experimental PFs and theoretical PFs, it can be concluded that the FEDIOL approach can be recommended as a suitable tool when PFs derived from specific processing studies are missing. Similar studies on pesticides with wider ranges of log Pow are required in order to complete our conclusions on default PFs for vegetable oils. [ABSTRACT FROM AUTHOR]

South Korea has a unique food culture. South Koreans enjoy wrapping meat and eating or makingkimchi(traditionally fermented Korean food) and eating using raw leafy vegetables, stalk and stem vegetables. Therefore, there is a high chance of being exposed to pesticide residues of vegetables. The objective of this study was to investigate pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea. A total of 8496 samples were mainly collected from Gwangju and Jeonnam area (the largest production region of leafy vegetables, stalk and stem vegetables) in South Korea from 2010 to 2014. A total of 230 pesticides were used for multi-residue analysis of pesticides. Among 8496 samples, 61 different pesticides (1029 times) were detected in 890 samples, of which 118 samples (1.4%) exceeded the Korea maximum residue limits (MRLs). Samples exceeding the MRLs were mostly found in leafy vegetables (brassica lee ssp. namai, leafy lettuce, spinach, perilla leaves, crown daisy, marsh mallow, aster scaber, pimpinella brachycarpa) and Chinese chive. Procymidone, dimethomorph and azoxystrobin were the most frequently found pesticides. A risk assessment of pesticides exceeding the MRLs was evaluated by calculating the estimated daily intake (EDI) and the acceptable daily intake (ADI). The ratio of EDI to ADI was 0.003–30.4%. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the residues of 140 pesticides in raspberries from north-eastern Poland (2005–2010). Gas chromatography with electron capture detector (GC-ECD) and nitrogen phosphorous detector (GC-NPD) was used. Among the 128 samples, 66 (51.6%) were found to detect residues: 14.1% contained one pesticide and around 38% multiple pesticide residues. The most frequently detected were pyrimethanil residues (36.0%). Twenty-seven (21.1%) raspberry samples exceeded the maximum residue limits. The estimated daily intakes ranged from 0.003% to 3.183% of the acceptable daily intake (ADI) for adults 0.008% and 9.7% for toddlers, respectively. The most critical case is procymidone, the acute risk was 180.9% of acute reference dose (ARfD) for toddlers and for adults (83% of ARfD) which is high. [ABSTRACT FROM AUTHOR]

The Gharb region in Morocco is an important agricultural zone where soils receive pesticide treatments and organic amendments to increase yields. The groundwater aquifer in the Gharb region is relatively shallow and thus vulnerable. The objective of this work was to study the influence of organic amendments on diuron, cyhalofop-butyl and procymidone leaching through undisturbed soil columns. Two soils were sampled from the Gharb region, a Dehs (sandy soil) and a R’mel (loamy clay soil). Following elution (124.5 mm), the amount of pesticide residues in the leachates of the sandy soil (0.06–0.21 %) was lower than in those of the loamy clay soil (0.20–0.36 %), which was probably due to preferential flow through the loamy clay soil. The amount of procymidone leached through the amended soil columns was greater than the control for the sandy soil only. The organic amendments did not significantly influence diuron and cyhalofop-butyl leaching in either of the soils. The application of organic amendments affected the amounts of dissolved organic matter (DOM) eluted and thus pesticide leaching as a function of soil-type. Nevertheless, in some case, the formation of pesticide-DOM complexes appeared to promote pesticide leaching, thus increasing groundwater contamination risks. [ABSTRACT FROM AUTHOR]

Mature red cherry tomato fruit (Lycopersicon esculentum var. cerasiforme) were treated with hot water (HWT) at 45°C, and/or with 2% (w/v) sodium bicarbonate solution (SBC), alone or in combination (HWT + SBC) for 10 min, then stored at 20°C for 6 d. HWT alone caused fruit cracking, while no cracking was observed on SBC-treated, or on HWT + SBC-treated fruit. Scanning electron microscopy showed that the combined SBC + HWT treatment made the fruit surface relatively homogeneous, compared with untreated control fruit or either treatment alone. The combined treatment also reduced the residual procymidone fungicide content of fruit, compared with the individual treatments. After storage, fruit from the combined treatment had higher skin firmness and titratable acidity, with a lower incidence and lesion diameter of grey mould rot caused by Botrytis cinerea, compared with untreated control fruit or either treatment alone. Our results suggest that HWT alone was not suitable for mature red cherry tomato fruit, while a combination of HWT plus SBC has potential as a commercial treatment to avoid fruit cracking, to improve safety, and to maintain fruit quality. [ABSTRACT FROM AUTHOR]

We used three non-linear bi-phasic models, bi-exponential (BEXP), first-order double exponential decay (FODED), and first-order two-compartment (FOTC), to fit the measured degradation data for six commonly used pesticides (atrazine, terbuthylazine, bromacil, diazinon, hexazinone and procymidone) in two New Zealand soils. Corresponding DT50 and DT90 values for each compound were numerically obtained and compared against those estimated by simple first-order kinetic (SFOK) model. All 3 non-linear models gave good fit of the measured data under both soil depths and were well supported by the values obtained for the respective statistical indices (RMSE, CRM and r2). The FOTC model gave by far the best fit for most compounds, followed by the FODED and BEXP models. Overall, DT50 values derived by non-linear models for the six compounds in soils from both sites were lower than the values obtained by the SFOK model. Differences in the SFOK and the three non-linear models derived DT90were, however, an order of magnitude higher for some compounds, while for others differences were very small. Although all three non-linear models described most data by giving excellent fits, in a few instances > 5-10% asymptotes hindered the estimation of DT90 values. This work shows that when degradation deviates from first-order kinetic, application of non-linear decay models to describe the kinetics of degradation becomes important in order to derive the true end-points for pesticides in soil. [ABSTRACT FROM AUTHOR]

The dissipation of two fungicides (procymidone and azoxystrobin) was evaluated in greenhouse grown lettuce and under cold storage conditions. Lettuce samples were collected from an experimental greenhouse during a five week period, in which two consecutive applications of these pesticides were performed. Gas chromatography (GC) with electron-capture detection (ECD) was used to study the disappearance of these compounds in lettuce. Confirmation analysis of pesticides was carried out by capillary gas chromatography coupled with mass spectrometry in the selected ion monitoring (SIM) mode. The disappearance rates of these compounds on lettuces in field after two applications were described as pseudo-first-order kinetics with strong correlation between residue concentration and time (r was in all cases higher than 0.983). The half-lives for first and second applications were of 5.31 and 4.65 days for procymidone and 6.23 and 4.87 days for azoxystrobin, respectively. When procymidone and azoxystrobin were applied two times during cultivation, at maximum recommended dose, the residues of both pesticides were below maximum residue limits (MRLs) after the established preharvest intervals. After 21 days under cold and darkness storage conditions, dissipation of procymidone and azoxystrobin was not observed. [ABSTRACT FROM AUTHOR]

The transport and fate of selected pesticides was determined at seven field sites located throughout New Zealand. Mixtures of pesticides and bromide (Br) were applied to plots and soil and water samples, collected at 1-3 monthly intervals over the study period, were analysed for residual pesticides and Br. The maximum depth of sampling varied from 0.92 to 2.5 m for the suction cup samplers and 0.8 to 1.0 m for the soil sampling. Inverse modelling was used with three models, GLEAMS, LEACHM, and HYDRUS, to estimate Koc and half-life values for the applied pesticides. Diazinon and procymidone had much lower Koc values than the selected literature values (SLVs), indicating they will be much more mobile in New Zealand soils than would be expected from the SLVs. Picloram had similar Koc values to the SLV at the Te Awa and Twyford sites but was much less mobile in the allophanic Horotiu soil, as was triclopyr. There was a slight effect of allophane on sorption for hexazinone, picloram, and triclopyr for the Horotiu and Kiripaka soils. Atrazine, simazine, and terbuthylazine Koc values tended to be less than the SLV, whereas bromacil Koc values were greater than the SLV and hexazinone had similar Koc values to the SLV. Diazinon, hexazinone, simazine, and terbuthylazine all had similar half-life values to the SLVs. Atrazine was on average c. 4 times less persistent than the SLV, whereas bromacil was slightly less persistent than the SLV. 2,4-Dd was about twice as persistent as the SLV would indicate whereas picloram, triclopyr, and procymidone were much more persistent than the SLVs, with factors of 4, 5, and 50, respectively, for these pesticides, and were outside the reported range of literature values. These studies have provided a greater knowledge of field-based Koc and half-life values in New Zealand soils under a range of climatic conditions, and the measured variability in the Koc and half-life values can be used to carry out a sensitivity analysis of leaching predictions. [ABSTRACT FROM AUTHOR]

Peaches containing added residues of chlorpyrifos-methyl, fenitrothion, procymidone and vinclozolin were used for simulated industrial processing in the manufacture of baby food puree. Residues were determined in raw material, in intermediate products at crucial steps of the processing procedure and in final products. Determination of residues was performed by an analytical method, distinguished by high sensitivity, based on acetone extraction, a two-step clean-up/pre-concentration on graphitized carbon and SAX/PSA sorbent, and GC-ECD. The results of the study were interpreted with respect to enforcement of the stringent Maximum Residue Limit (MRL) of 0.01  mg  kg -1 established by the European Commission (EC) for any pesticide in baby food. Peeling was identified as the most effective procedure in reducing residues. Thermal treatment (concentration and sterilisation) substantially reduced organophosphate (chlorpyrifos-methyl, fenitrothion) residues, whereas procymidone and vinclozolin residue levels were increased in peach puree. [ABSTRACT FROM AUTHOR]

Two vibrational spectrometry–based methodologies were developed for procymidone determination in wettable powdered pesticide formulations. The Fourier‐transform infrared (FTIR) procedure was based on the selective extraction of procymidone by chloroform and determination by peak area measurement between 1451 and 1441 cm -1 , using a baseline correction established between 1490 and 1410 cm -1 , and a precision of 0.4% and a limit of detection of 0.01% w/w procymidone for a sample mass of 25 mg were obtained. For FT‐Raman determination, the selected conditions were peak area measurement between 1005 and 995 cm -1 Raman shift, with a baseline correction fixed between 1030 and 947 cm -1 , and a relative standard deviation of 1% and a limit of detection of 0.8% procymidone in the original sample were obtained. The sample frequency for FTIR determination was 30 hr -1 , lower than that for Raman with 40 hr -1 . FT‐Raman reduces to the minimum the reagent consumption and waste generation, also avoiding the sample handling and contact of the operator with the pesticide. It can be concluded that the proposed methods are appropriate for quality control in commercial pesticide formulations. [ABSTRACT FROM AUTHOR]