A Miniaturized Sample Preparation Method for the Determination of Vitamins A and E in Food Products

A new analytical approach to the simultaneous identification and quantification of vitamins A and E in three representative matrices (Parmesan, spinach, and almonds) was developed. The analyses were based on high-performance liquid chromatography with UV-VIS/DAD detection. The procedure was optimized by a significant reduction in the weight of the tested products and quantities of reagents added during the saponification and extraction stages. A full method validation study was performed for retinol at two concentration levels (LOQ and 200 × LOQ), which showed satisfactory results, with recoveries ranging from 98.8 to 110.1%, and an average CV of 8.9%. Linearity was tested in the range of 1-500 µg/mL and showed the coefficient of determination R² = 0.999. The satisfactory recovery and precision parameters were achieved for α-tocopherol (LOQ and 500 × LOQ) in the range of 70.6-143.2%, with a mean CV equal to 6.5%. The observed linearity for this analyte in the concentration range of 1.06-532.0 µg/mL was R² = 0.999. The average extended uncertainties were estimated, using a top-down approach of 15.9% and 17.6% for vitamin E and A, respectively. Finally, the method was successfully applied to determine vitamins in 15 commercial samples.

Analysis of Residues in Environmental Samples

The state of the environment is very important for our lives and for that of future generations [...]

Simultaneous Determination of Multi-Class Pesticide Residues and PAHs in Plant Material and Soil Samples Using the Optimized QuEChERS Method and Tandem Mass Spectrometry Analysis

New analytical approaches to the simultaneous identification and quantification of 94 pesticides and 13 polycyclic aromatic hydrocarbons (PAHs) in five representative matrices (pepper, apple, lettuce, wheat, and soil) were developed. The analyses were based on gas chromatography coupled with triple quadrupole tandem mass spectrometry (GC-MS/MS). The procedure was optimized by changing the solvent used during the extraction, from acetonitrile to the acetone: n-hexane mixture at a volume ratio of 1:4 (v/v), as well as the use of a reduced amount of water during the extraction of compounds from cereals. An additional modification was the use of florisil instead of GCB in the sample cleanup step. A full method validation study was performed, at two concentration levels (LOQ and 1000 × LOQ), which showed satisfactory results for all analytes from the PAHs group, with recoveries ranging from 70.7-115.1%, and an average RSD of 3.9%. Linearity was tested in the range of 0.001-1.000 mg/kg and showed coefficients of determination (R²) ≥ 0.99 for all PAHs. Satisfactory recovery and precision parameters (LOQ and 100 × LOQ) were achieved for almost all analytes from the pesticide group in the range of 70.1-119.3% with the mean RSD equal to 5.9%. The observed linearity for all analytes in the concentration range of 0.005-1.44 mg/kg was R² ≥ 0.99, with the exception of famoxadone, chizalofop-p-ethyl, prothioconazole, spirodiclofen, tefluthrin, and zoxamid. The extended uncertainties were estimated, using a top-down approach of 9.9% (average) and 15.3% (average) for PAHs and pesticides samples, respectively (the coverage factor k = 2, the 95% confidence level). Ultimately, the method was successfully applied to determine pesticide residues in commercial samples of fruit, vegetables and grain, and soil samples for PAHs, which were collected from selected places in the Podkarpacie region. A total of 38 real samples were tested, in which 10 pesticides and 13 PAHs were determined. Proposed changes allow us to shorten the sample preparation time (by 20%) and to reduce the consumption of organic solvents (by 17%). The use of florisil for sample cleanup, instead of GCB, improves the recovery of compounds with flat particles.

Influence of Bacillus subtilis and Trichoderma harzianum on Penthiopyrad Degradation under Laboratory and Field Studies

In plant protection, biological preparations are used alternately with chemical pesticides. The applied microorganism can influence the concentration of chemical substances. Laboratory and field studies were conducted to assess the influence of Bacillus subtilis and Trichoderma harzianum on the penthiopyrad concentration. In laboratory studies, the effectiveness of penthiopyrad degradation by B. subtilis was approximately 5% during 14 days of the experiment. For penthiopyrad treated with T. harzianum strains, the degradation effectiveness ranged from 34.2% on Day 3 to 56.9% on Day 14. In experiments testing the effects of mixed culture of microorganisms, the effectiveness of penthiopyrad degradation ranged from 23.7% on Day 3 to 29.1% on Day 14. After treatment of apple trees of Gala and Golden Delicious varieties with a biological preparation, a maximum degradation of penthiopyrad of 20% was found in both varieties. Samples of apples were prepared by the quick, easy, cheap, effective, rugged and safe (QuEChERS) method, and penthiopyrad was analyzed by gas chromatography with a mass detector. A determined value of the chronic exposure to penthiopirad was 1.02% of the acceptable daily intake, both for children and for adults. The acute exposure amounted to 7.2% and 1.9% of the acute reference dose for children and adults, respectively. These values were considered to be acceptable and not threatening to health.

Influence of a Commercial Biological Fungicide containing Trichoderma harzianum Rifai T-22 on Dissipation Kinetics and Degradation of Five Herbicides in Two Types of Soil

Biological crop protection is recommended to be applied alternately or together with chemical one, to protect human health from the excessive use of toxic pesticides. Presence of microorganisms can influence the concentration of chemical pollutants in soil. The aim of this study is to estimate the influence of a commercial biological fungicide containing Trichoderma harzianum Rifai T-22 on dissipation kinetics and degradation of five herbicides belonging to different chemical classes: clomazone, fluazifop-P-butyl, metribuzin, pendimethalin, and propyzamide, in two types of soil. Results of the study revealed that T. harzianum T-22 influences pesticide degradation and dissipation kinetics of the non-persistent herbicides: clomazone, fluazifop-P-butyl, and metribuzin. In soil with a higher content of nitrogen, phosphorus, and organic matter, degradation increased by up to 24.2%, 24.8%, and 23.5% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In soil with lower organic content, degradation was on a low level, of 16.1%, 17.7%, and 16.3% for clomazone, fluazifop-P-butyl, and metribuzin, respectively. In our study, the addition of the biological preparation shortened herbicide dissipation half-lives, from 0.3 days (2.9%) for fluazifop-P-butyl, to 18.4 days (25.1%) for clomazone. During the degradation study, no significant differences were noticed for pendimethalin, belonging to persistent substances. Biological protection of crops can modify pesticide concentrations and dissipation rates. On one hand, this may result in the reduced effectiveness of herbicide treatments, while on the other, it can become a tool for achieving cleaner environment.

The difference in dissipation of clomazone and metazachlor in soil under field and laboratory conditions and their uptake by plants

The study concerned dissipation of metazachlor and clomazone, herbicides widely used in rapeseed (Brassica napus L. subsp. napus) protection, applied to the clay soil under field and laboratory conditions. Furthermore, the uptake of these pesticide from soil by rapeseed plants was investigated under field conditions. An additional aim of this work was to modify the QuEChERS method for the determination of metazachlor and clomazone in the plant material. Analytical procedures for metazachlor and clomazone qualification and quantification in rapeseed plants and soil were developed, using gas chromatography with an micro electron capture detector (GC-μECD) and a mass detector (GC-MS/MS QqQ) as confirmation. Dissipation kinetics of herbicide residues in soil were described as first-order equations. The analytical performance was very satisfactory and confirmed that the methods meet the requirements of the European Commission. In the conducted field experiments it was found that dissipation of clomazone and metazachlor in clay soil follows first-order kinetics (R2 between 0.964 and 0.978), and half-lives were 9.5 days and 10.2 days for clomazone and metazachlor, respectively. Under laboratory conditions, dissipation of clomazone and metazachlor in soil also follows first-order kinetics (R2 between 0.937 and 0.938), and half-lives were 8.8 days and 5.7 days for clomazone and metazachlor, respectively. Residues of both herbicides in rape plants 22 days after application of herbicides were below the maximum residue levels for Brassica plants. Metazachlor and clomazone dissipate very fast in clay soil and their uptake by rape plants is very low.

Selected food processing techniques as a factor for pesticide residue removal in apple fruit

In this study, various food processing techniques, including high-temperature processes (pasteurization/sterilization and boiling), low-temperature processes (freezing), mechanical processing (peeling and juicing), and water-based processes (washing with tap water and ultrasonic washing) were used to identify the most effective way to remove contamination of 5 fungicides (cyprodinil, difenoconazole, fluopyram, tebuconazole, and fludioxonil). The most effective processes were juicing and freezing in the range between 63 and 100% and from 52 to almost 100%, respectively. Ultrasonic washing and boiling also significantly removed pesticide residues ranging from 79 to 84% and from 72 to 78%, respectively. The same trend was observed by peeling process where maximum reduction of 80% was achieved almost for all fungicides. Washing with tap water decreased the concentration levels in the range of 35-38%. This study demonstrated that the least effective and unpredictable method of decontamination of pesticides was sterilization and pasteurization, due to the large variation in pesticide levels during the process.

Consumer health risk to pesticide residues in Salvia officinalis L. and its infusions

Salvia officinalis L. is a popular herb widely used in culinary, cosmetic, and medicinal preparations, and also as an ornamental plant. Sage crops are threatened by many diseases, such as gray mold, powdery mildew, and leaf spot, by weeds, and by pests, such as aphids. Use of crop protection products may lead to presence of pesticide residues in this herb. The aim of this work was to study presence of pesticide residues in the herb, S. officinalis L., available on the retail market in Poland, to verify their compliance with the maximum residue levels (MRLs) and to assess the chronic and acute risks associated with consumption of this herb and infusions prepared from contaminated sage plants. Ninety active substances of pesticides were analyzed, including all active substances registered in Poland for protection of the sage. Five active substances were found, one fungicide - boscalid and four insecticides: chlorpyrifos, pp'-DDT, dimethoate (residue levels above MRL) and indoxacarb. The chronic and acute exposure to pesticide residues consumed with sage did not exceed 0.02% of the acceptable daily intake (ADI) and 0.1% of the acute reference dose (ARfD), respectively.

Dissipation of chlorantraniliprole, chlorpyrifos-methyl and indoxacarb-insecticides used to control codling moth (Cydia Pomonella L.) and leafrollers (Tortricidae) in apples for production of baby food

Dissipations of three insecticides: chlorantraniliprole, chlorpyrifos-methyl and indoxacarb in apples were studied following their foliar application on apples intended for production of baby food. The apples were sprayed with formulations for control of codling moth (Cydia Pomonella L.) and leafrollers (Tortricidae). Six experiments were conducted; each insecticide was applied individually on dessert apples. A validated gas chromatography-based method with simultaneous electron capture and nitrogen-phosphorus detection (GC-ECD/NPD) was used for the residue analysis. The analytical performance of the method was satisfactory, with expanded uncertainties ≤36% (a coverage factor, k = 2, and a confidence level of 95%). The dissipations of insecticides were studied in pseudo-first-order kinetic models (for which the coefficient of determination, R ² , ranged between 0.9188 and 0.9897). Residues of studied insecticides were below their maximum residue limits of 0.5 mg/kg at an early stage of growth of the fruit. The half-lives of chlorantraniliprole, chlorpyrifos-methyl and indoxacarb were 16-17, 4-6 and 20-24 days, respectively. The initial residue levels declined gradually and reached the level of 0.01 mg/kg in 1 month for chlorpyrifos-methyl, 2 months for chlorantraniliprole and 2.5 months for indoxacarb. To obtain the insecticide residue levels below 0.01 mg/kg, which is the default MRL for food intended for infants and young children, the application of the studied insecticides should be carried out at recommended doses not later then: 1 month before harvest for chlorpyrifos-methyl, 2 months for chlorantraniliprole and 2.5 months for indoxacarb.

Dissipation kinetics of alpha-cypermethrin and lambda-cyhalothrin residues in aboveground part of white mustard (Sinapis alba L.)

Dissipation of simultaneously applied insecticides alpha-cypermethrin and lambda-cyhalothrin was studied in a minor crop, aboveground part of white mustard (Sinapis alba L.). A validated gas chromatographic method (GC-ECD/NPD) was used to determine insecticide residues. Analytical performances were very satisfactory, with expanded uncertainties not higher than 14% (coverage factor k = 2, confidence level 95%). Dissipation of alpha-cypermethrin and lambda-cyhalothrin in white mustard followed first-order kinetics (R(2) between 0.953 and 0.995), with half-lives of 3.1-4.6 and 2.9-3.7 days respectively. Based on the results of this two-year study and the relevant residue regulation, alpha-cypermethrin and lambda-cyhalothrin treatments can be considered safe for crop protection, feeding animals and the environment.

Occurrence and estimation of pesticide residues in edible minor crops in southeastern Poland in 2013-2014

This paper presents the results of official control of pesticide residues in minor crops collected in southeastern Poland in 2013-2014. Compliance of used pesticides with applicable law was also verified, and determined residues were compared to maximum residue levels (MRLs) provided for in Regulation (EC) No. 395/2005. A total of 583 samples of 25 different types of fresh fruit and vegetables were analyzed for pesticide residues. Pesticide residues were detected in 158 samples (27.1 % of the analyzed samples). According to the European Commission Health & Consumer Protection Directorate-General (SANCO) guidelines document, MRL violations were understood as cases where a residue level exceeded the MRL after the uncertainty of the method (50 %) was considered. MRL violations were found in four samples. The usage of unauthorized pesticides was detected in 5.8 % of analyzed samples. Substances banned in Poland were found in two samples. Fungicides were the most frequently detected group of pesticides. Pesticide residues were most commonly found in fruit samples (19.4 % of all analyzed samples), mainly in gooseberry, redcurrant, and huckleberry. The majority of samples were compliant with MRLs, which means that they were suitable for trade.

Pesticide residues in raw agricultural products from the south-eastern region of Poland and the acute risk assessment

BACKGROUND

The use of pesticide leads to the increase in quantity and quality of yields, but may also result in presence of toxic contaminants in food products.

OBJECTIVE

The aim of this study was to evaluate presence of pesticide residues in raw agricultural products from the south-eastern region of Poland, to verify their compliance with the maximum residue levels' (MRLs) as specified in the EU regulations concerning products present in the market, and to assess the acute risk related to consumption of these products.

MATERIAL AND METHODS

Samples of raw agricultural products were obtained from production farms as a part of an official premarket monitoring of pesticide residues conducted on behalf of the Ministry of Agriculture and Rural Development, implemented in cooperation with the regional Inspectorates of Plant Health and Seed Inspection. The scheduled tests covered determination of 243 chemicals included in residue definitions for purposes of pesticide residues monitoring in or on food of plant origin (229 pesticides).

RESULTS

In 2015, a total of 328 samples of raw commodities collected from the south-eastern region of Poland were analysed for the presence of pesticide residues. Pesticide residues were detected in 84 samples (25.6%), while in 7 samples (2.1%) they exceeded MRLs. Violations of MRLs concerned 2 samples of Peking Cabbage, 3 samples of dill, 1 sample of raspberry and 1 sample of spinach. The pesticide residues were most often found in: fruit (38.3% of all fruit samples), herbs (35.3%) and vegetables (20.0%). The assessed acute exposure did not exceed the 100% acute reference dose (ARfD) in any sample.

CONCLUSIONS

Monitoring of pesticide residues in the agricultural crops prevents penetration of products with MRLs exceeded or containing unacceptable pesticide residues into the market, thus protecting consumers' health.

KEY WORDS

pesticide residues, agricultural products, risk assessment, multiresidue method.

Occurrence of pesticide residues in fruiting vegetables from production farms in south-eastern region of Poland

BACKGROUND

Considering the fact that pesticides are commonly used in agriculture, continuous monitoring of these substances in food products is of great significance. Residues of these substances can be present in crops after harvest.

OBJECTIVE

The aim of this study was to evaluate presence of pesticide residues in fruiting vegetables from production farms in south-eastern region of Poland in 2012–2015.

MATERIAL AND METHODS

138 samples were tested using accredited test methods. The monitoring programme covered determination of 242 pesticides. The tests covered tomato, cucumber and pepper crops. The test results were interpreted in accordance with criteria included in the European Commission recommendations published in the document SANCO/12571/2013 (now superseded by Document SANTE 2015), as well as on a basis of the maximum residue levels in force in the EU Member States.

RESULTS

Pesticide residues were found in 47 samples, representing 34% of all tested samples. 17 active substances were found, belonging to fungicides and insecticides. Azoxystrobin (38%), boscalid (28%) and chlorothalonil (21%) were most commonly found in fruiting vegetables testing samples. Non-compliances related to use of plant protection product not authorized for protection of a given crop were observed in 6% of analysed samples. However, pesticide residues of fruiting vegetables in quantities that exceed the maximum residue levels (NDP, ang. MRLs), as well as substances which use for plant protection is forbidden were no found.

CONCLUSIONS

Crops monitoring is used to determine to what extent such products are contaminated with pesticide residues, and ensures protection of customer health.

Pesticide residues in fruit and vegetable crops from the central and eastern region of Poland

BACKGROUND

Fruit and vegetables have health and nutritional value, but can also be a source of toxic contaminants such as pesticide residues.

OBJECTIVE

The aim of this study was to evaluate presence of pesticide residues in fruit and vegetable crops from the central and eastern region of Poland in order to check the compliance of these products with the maximum residue levels' (MRLs) requirements set in legal EU regulation for products present in the market.

MATERIAL AND METHODS

Samples of fruit and vegetables were obtained from production farms as a part of an official premarket monitoring of pesticide residues conducted on behalf of the Ministry of Agriculture and Rural Development, implemented in cooperation with the regional Inspectorates of Plant Health and Seed Inspection. The tests covered determination of 207 pesticides.

RESULTS

In 2014, a total of 317 samples of fruit and vegetables, collected from the central and eastern region of Poland, were analysed for the presence of pesticide residues. Pesticide residues were detected in 89 (28.1%) analysed samples: in 65 (38.2%) samples of fruit, and in 24 (16.3%) samples of vegetables. MRLs were exceeded in 2 samples (0.6%). Most often, the pesticide residues were found in gooseberry (100% of gooseberry samples) and apple (71.4%).

CONCLUSIONS

Monitoring of pesticide residues in the agricultural crops at premarket stage should be continued to prevent market from the penetration by products with non-acceptable residues of pesticides and to protect consumers against excessive exposure to pesticide residues.

Pesticide residues in stone fruits from the south-eastern region of Poland in 2012-2104

BACKGROUND

Peaches, sour cherries, nectarines, apricots, plums and cherries are fruit commonly known as "stone fruit". Their nutritional properties namely, vitamins, minerals, fiber and numerous microelements, make them a very important component of human diet. As fruit trees can be attacked by numerous diseases and pests, chemical protection of these crops is used. Therefore, it is important that the relevant governmental agencies or institutions ensure correct application of pesticides.

OBJECTIVE

The aim of the study was to evaluate the occurrence of pesticide residues in stone fruits south-eastern region of Poland in 2012-2014 in order to provide data to estimate health risk to consumers.

MATERIAL AND METHODS

Validated analytical methods based on liquid / liquid extraction coupled with gas chromatography with electron capture and nitrogen phosphorus detection (GC-ECD/NPD) and spectrophotometry (dithiocarbamates residues) were used for the analysis. 92 samples of stone fruits were tested for the presence of pesticide residues.

RESULTS

13 of all samples (14%) contained pesticide residues. 7 active substances were detected, including 5 fungicides: boscalide, bupirimate, difenoconazole, dithiocarbamates and captan, and 2 insecticides: cypermethrin and pirimicarb. In the analysed samples, the use of not recommended plant protection products in orchard crops were found. However, neither maximum residue levels (MRLs) recommended by the Regulation (EC) No 396/2005 were exceeded nor pesticides being unapproved by the Regulation (EC) No 1107/2009 detected in the analysed samples.

CONCLUSIONS

Lack of plant protection products for control specific diseases or pests in crops results in the use of formulations not recommended for use in certain orchard crops. On a basis of results reported in previous years it can be concluded that occurrence of pesticide residues in stone fruit samples dropped significantly.

Consumer exposure to pesticide residues in apples from the region of south-eastern Poland

The production of apples in Poland is the largest among the countries of the European Union, and therefore, the consumption of these fruits is high in our country. The aim of this study was to determine the presence of pesticide residues in Polish apples and to assess if these residues pose a risk to the health of the consumer. Furthermore, compliance with legal regulations concerning the use of plant protection products in crop cultivation was ascertained. Pesticide residues were found in 192 samples (61.5% of tested samples). In six samples (1.9%), residues exceeded maximum residue limits. Violations concerned the insecticides: indoxacarb, diazinon and fenitrothion. The highest long-term consumer exposure was found in the case of consumption of apples with diazinon residue for both groups, adults and toddlers [4% acceptable daily intake (ADI), adults; 21% ADI, toddlers]. The highest values of short-term exposure were obtained in the case of consumption of apples with indoxacarb [5% acute reference dose (ARfD), adults; 27% ARfD, toddlers] and fenitrothion (4% ARfD, adults; 23% ARfD, toddlers). Although fungicides are the pesticides found most often in apples, the consumption of apples with insecticide residues constitutes the greatest hazard to human health.

Pesticide residues in berries harvested from South-Eastern Poland (2009-2011)

BACKGROUND

Poland is a leading grower/producer of berries in Europe that are either eaten raw or processed. As well as berries this includes fruit such as grapes, strawberries and other small fruits. Testing for the presence of active substances in Plant Protection Products, (PPP), in such fruit is however important, as part of measures taken to minimise human intake.

OBJECTIVE

To determine the incidence of pesticide residues in berries harvested from South-Eastern Poland in 2009-2011.

MATERIAL AND METHODS

. Chromatographic separation followed by analytical detection was performed on 250 samples of various test fruits using an accredited methodology: GC/ECD/NPD, together with spectrophotometric detection wherever necessary, according to PN-EN ISO/IEC 17025. As part of previous monitoring, 126 active substances were identified in 2009, 132 in 2010 and 153 in 2011; levels were compared to Maximum Residue Limits (MRLs). RESULTS;. Analyses showed that 46.4% of samples contained PPPs of which 4% exceeded the MRL. The most were found in raspberries, (58.8% of all tested), followed by 58.3% redcurrants, and gooseberries as well as 50% grapes. The most frequently found active substances of PPPs were pyrimethanil (15.6%), dithiocarbamates (12.4%), procymidone (8%), cyprodinil (5.6%) and difenoconazole (5.2%). The highest MRL exceedances were found in blackcurrants. Testing also revealed many examples of pesticides not recommended for the protection of specific crops: propiconazole in gooseberries, cyprodinil, flusilazole, iprodione, pyrimethanil in blackcurrants and folpet and captan in raspberries. Furthermore, active substances whose use in PPPs have been forbidden since 2008 were also detected, ie. endosulfan in blackcurrants and strawberries, fenitrothion in black and red currants as well as procymidone in raspberries, blackcurrants and strawberries. These data are consistent to those obtained from the whole of Poland and the European Union (EU).

CONCLUSIONS

Most pesticides were present in raspberries, redcurrants, gooseberries and grapes of which fungicides were the most frequently detected. These results are in keeping with other similar studies.

Analysis of pesticide residues in fresh peppermint, Mentha piperita L., using the quick easy cheap effective rugged and safe method (QuEChERS) followed by gas chromatography with electron capture and nitrogen phosphorus detection

A new analytical method for the determination of 14 pesticide residues in fresh peppermint was developed based on the QuEChERS sample preparation technique followed by gas chromatography coupled to electron capture and nitrogen phosphorus detectors (GC/ECD/NPD). The validation study clearly demonstrated suitability of the method for its intended application. The overall recoveries of the pesticides from peppermint, at the three spiking levels of 0.01, 0.1 and 1.0 mg kg(-1), were 100% ± 10% with relative standard deviations of 6% ± 5% on average. The limit of quantification was 0.01 mg kg(-1) for all the pesticides. The expanded uncertainties were in the range between 7% and 30% (14% on average), which was distinctively less than a maximum default value of ±50%. Compared with our previous method, that entailed dichloromethane/acetone extraction and florisil column cleanup with collection of four fractions, the new method was more straightforward, less time and labour intensive as well as more sensitive, selective and accurate, simultaneously.

[Occurrence of plant protection product residues in apples in 2007]

The aim of this paper was to present occurrence of plant protection product residues in apples in 2007. Gas chromatographic and spectroscopy methods were used. The most frequently found were fungicides: dithiocarbamate residues (18% of the analysed samples), captan residues (13%), pyrimethanil residues (6%) and insecticides: chlorpiryfos residues (6%), diazinon residues (6%) and pirimicarb residues (5%). 5.6% of analysed samples exceeded the national Maximum Residue Level established for apples. Violations were found for: flusilazole (n = 2), propiconazole (n = 2), cyprodinil (n = 1), dimethoate (n = 1), fenitrothion (n = 1).