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Öğe Determination of 115 pesticide residues in oranges by high-performance liquid chromatography-triple-quadrupole mass spectrometry in combination with QuEChERS method(Academic Press Inc., 2015) Gölge, Özgür; Kabak, BülentThe present study aims to determine 115 pesticide residues in 400 commercially available orange samples in Adana, Mersin and Hatay provinces of Turkey. Pesticide determination was carried out using liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation technique involved acetonitrile-based extraction of the samples, and followed by dispersive solid-phase extraction (d-SPE) cleanup using primary–secondary amine (PSA), was used prior to LC–MS/MS analysis. The method showed satisfactory linearity, specificity, recovery and precision. The limit of detection (LOD) and limit of quantification (LOQ) for target analytes were in the range of 0.001–0.011 mg kg?1 and 0.002–0.030 mg kg?1, respectively. The expanded measurement uncertainty was not higher than 45% for all target analytes. Only one insecticide and two fungicides were detected individually in a total of 30 orange samples. Chlorpyrifos was the predominant pesticide at levels ranging from 0.01 to 0.09 mg kg?1, while imazalil was detected in 3 samples (0.09–0.48 mg kg?1) and azoxystrobin was found in only 2 samples (0.02 and 0.03 mg kg?1).Öğe Determination of 355 Pesticides in Lemon and Lemon Juice by LC-MS/MS and GC-MS/MS(MDPI, 2023) Aslantaş, Şule; Gölge, Özgür; González-Curbelo, Miguel Ángel; Kabak, BülentAbstract: While pesticides have become a primary tool in modern agriculture, these compounds remain a high priority on the list of consumer concerns regarding food safety. The use of pesticides in the production and post-harvesting of lemon fruits is widely used to ensure agricultural yield and fruit quality. Therefore, monitoring studies on citrus fruits to enforce regulatory compliance and ensure food safety is in great demand. The aim of this study was to monitor multi-class pesticide residues in lemon fruits commercialized in Turkey. The transmission of residues that existed on the outer surface of the fruit into its juice was also studied. Whole fruits and lemon juice samples were prepared using the quick, easy, cheap, effective, rugged and safe (QuEChERS) methodology prior to analysis. For the screening and quantification of 355 pesticide residues, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) were used. The analytical method has been shown to have a sufficiently low limit of quantification with respect to current maximum residue limits (MRLs) for all target analytes. The obtained recovery and precision parameters fulfilled the requirements in DG SANTE guidelines. The in-house validated analytical method was then applied for the determination of 355 pesticide substances in 100 whole fruit samples and their juices. Sixteen different residues were detected in 43% of lemon fruits, whereas 57 lemon samples were pesticide-free. The MRLs exceedances were recorded in 29 lemon samples. The most frequently detected (17%) pesticide in lemon fruits was chlorpyrifos-methyl, with a range of 0.013–0.098 mg kg?1 . A lower frequency was detected for metamitron (10%, 0.027–0.118 mg kg?1 ), buprofezin (9%, 0.023–0.076 mg kg?1 ), pyriproxyfen (9%, 0.021–0.102 mg kg?1 ) and malathion (7%, 0.100–0.482 mg kg?1 ) in whole fruits. However, none of the pesticide residues were detected in lemon juice samples. These results showed that target analytes are unable to penetrate the lemon exocarp and/or endocarp. Keywords: food safÖğe Determination of aflatoxins in walnut sujuk and Turkish delight by HPLC-FLD method(Elsevier Ltd, 2016) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis study aims to assess the risk of aflatoxins (AFs) in traditional confectionery products (walnut sujuk and Turkish delight) of Turkey. A high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method was used for the determination of AFs. Evaluation of the method showed good selectivity, linearity, recovery and precision. The limit of quantification (LOQ) ranged from 0.106 to 0.374?gkg-1. The expanded measurement uncertainty was less than 40% for all target analytes. The validated method was successfully applied to the determination of AFs in 112 traditional confectionery products containing nuts (hazelnuts and walnuts). AFs were detected in 43.8% of walnuts and 60.9% of hazelnuts used as ingredients in walnut sujuk and Turkish delight and at levels ranging from 0.58 to 15.2?gkg-1 and 0.43-63.4?gkg-1, respectively. This means that AFs levels in walnut sujuk and Turkish delight were up to levels of 6.1 and 9.5?gkg-1, respectively. Six walnut samples and twenty-one hazelnut samples were above the EU maximum limits (MLs) of 2 and 5?gkg-1 for aflatoxin B1 (AFB1), respectively. © 2015 Elsevier Ltd.Öğe Dietary intake of sorbic and benzoic acids from tomato ketchup for adults and children in Turkey(Birkhauser Verlag AG, 2015) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis report aims to determine levels and dietary intake of sorbic and benzoic acids from tomato ketchup consumed in Turkey. During the period from September 2013 to October 2014, a total of 63 tomato ketchup samples were analysed by high performance liquid chromatography coupled with photodiode array detection (HPLC–PDA). The analytical method was successfully validated in terms of linearity, sensitivity, recovery, repeatability, within-laboratory reproducibility and measurement uncertainty. Sorbic and benzoic acids were detected in 63.5 and 52.4 % of ketchup samples at levels ranging from 37.5 to 1419 mg kg?1, and from 98.5 to 1284 mg kg?1, respectively. Fifteen tomato ketchup samples were above the European maximum levels (MLs) of 1000 mg kg?1 for the sum of sorbic acid—sorbates and benzoic acid—benzoates in non-emulsified sauces. The estimated daily intakes of sorbic and benzoic acids through tomato ketchup were 0.005 and 0.004 mg kg?1 b.w. for adults, and 0.012 and 0.01 mg kg?1 b.w. for children, respectively.Öğe Evaluation of QuEChERS sample preparation and liquid chromatography-triple-quadrupole mass spectrometry method for the determination of 109 pesticide residues in tomatoes(Elsevier Ltd, 2015) Gölge, Özgür; Kabak, BülentA multiresidue method based on modified QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation, followed by liquid chromatography tandem mass spectrometry (LC–MS/MS) was developed and validated for the determination of 109 selected multiclass pesticides in tomatoes. The recovery yields ranged from 77.1% to 113.2%, with repeatabilities of 4.4–19.2% and within-laboratory reproducibilities of 7.1–18.4%. The limit of detections (LODs) for target analytes in tomato extract were between 0.5 and 10.8 ?g kg?1, and the limit of quantifications (LOQs) were between 1.3 and 30.4 ?g kg?1. The expanded measurement uncertainty was not higher than 30% for all target analytes. The method has been successfully applied to the analysis of 345 tomato samples obtained from local markets and tomato traders. Residues of acetamiprid, azoxystrobin and triadimefon were identified and measured in 9.6% of tomato samples, ranging from 0.015 to 0.37 mg kg?1.Öğe First report: Exposure estimates to ochratoxin a through wheat bread and rice intake in Turkey(Academic Press, 2016) Gölge, Özgür; Kabak, BülentA total of 160 samples of fresh wheat bread and rice from Turkey were analysed for the presence of ochratoxin A (OTA). The samples were analysed using a high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The method was previously validated and showed good selectivity, linearity, sensitivity and accuracy. The uncertainty associated with the analytical method was less than 20%. OTA was found in 9.8% of wheat bread (10 out of 102 samples) and 5.2% of rice (3 out of 58 samples) at levels ranging fromÖğe Health risk assessment of selected pesticide residues in green pepper and cucumber(Elsevier Ltd, 2018) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentThis report describes levels of 170 pesticide residues in green pepper and cucumber marketed in Turkey. The report also comprises the outcome of the consumer risk assessment of selected pesticides. In total, 725 samples of vegetables were analysed for residues of 170 distinct pesticides by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The in-house validation data fulfilled the requirements of the European SANTE/11945/2015 Guideline. The limit of quantifications (LOQs) varied from 0.003 to 0.016 mg kg-1. Recoveries ranged between 80.5 and 118.2%, with inter-day precisions of 0.7–19% relative standard deviation (RSD). The expanded measurement uncertainty for individual pesticides ranged from 10.4 to 42.4%. Overall, 12.9% of green peppers and 13.5% of cucumbers contained at least one detectable residue, but the levels were below the EU legal limits. For adults, the Hazard Quotients (HQs) for identified pesticides in green peppers and cucumbers ranged from 0.0003 to 0.0143%, and from 0.0001 to 0.0103%, respectively. Propamocarb and chlorpyrifos were the major contributors to hazard index (HI) for green pepper and cucumber, respectively. The results showed that there is no reason to be concerned about cumulative exposure to residues from green pepper and cucumbers for Turkish population. © 2018 Elsevier LtdÖğe Incidence and level of aflatoxin contamination in chilli commercialised in Turkey(Elsevier Ltd, 2013) Gölge, Özgür; Hepsağ, Fatma; Kabak, BülentDuring the years 2011–2012, a total of 182 chilli samples were collected from two provinces of Turkey and checked for aflatoxins (AFs). The samples were analysed using immunoaffinity column (IAC) clean-up and high performance liquid chromatography coupled to a fluorescence detector (HPLC-FLD) after post-column derivatisation. Quantification limits were 0.111, 0.110, 0.115 and 0.140 ?g kg?1 for aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2), respectively. Aflatoxins were found in 150 out of 182 analysed samples: one hundred and fifty samples with AFB1, eighty-four samples with AFB2 and thirty-two samples with AFG1. No AFG2 were detected in chilli samples above the quantification limit of 0.14 ?g kg?1. The ranges for positive samples were 0.24–165 ?g AFB1 kg?1, 0.15–11.3 ?g AFB2 kg?1 and 0.15–3.88 ?g AFG1 kg?1. Fifty and thirty-five samples of chilli exceeded the legal limits of 5 and 10 ?g kg?1 established by European Commission for AFB1 and total AFs (the sum of AFB1, AFB2, AFG1 and AFG2), respectively.Öğe Pesticide Residues in Table Grapes and Exposure Assessment(American Chemical Society, 2018) Gölge, Özgür; Kabak, BülentThis report describes levels of 172 pesticide residues in table grapes in Turkey. A total of 280 samples of table grapes were collected from supermarkets, bazaar, and greengrocer shops located in four provinces of Turkey from August to October 2016. The samples were analyzed by liquid chromatography coupled to tandem mass spectrometry. The limit of quantification ranged from 0.002 to 0.010 mg kg -1 . The validation data revealed good recoveries and good repeatability and reproducibility and fulfilled the other requirements of the European SANTE/11945/2015 Guideline. One or more pesticide residues were detected in 59.6% of the table grapes. The residues above the EU maximum residue levels were 20.4% of the samples. The most prevalent pesticide residues were azoxystrobin, chlorpyrifos, boscalid, and cyprodinil. Left-censored results (40.4% of the results) were substituted by lower bound, middle bound, and upper bound values. In the worst-case scenario, the hazard index (HI) was 3.37% for adults and 9.42% for children. Chlorpyrifos was the major contributor (65%) to HI. © 2018 American Chemical Society.Öğe Quantification of 363 Pesticides in Leafy Vegetables (Dill, Rocket and Parsley) in the Turkey Market by Using QuEChERS with LC-MS/MS and GC-MS/MS(MDPI, 2023) Deveci, Bilge; Gölge, Özgür; Kabak, BülentAbstract: Contamination of agricultural products with pesticide residues is a growing concern due to their adverse health effects and increasing worldwide usage of pesticides. In 2021 a total of 200 samples of green leafy vegetables, including 80 dill, 80 rocket and 40 parsley, purchased from greengrocer shops, markets and bazaars in Corum Province, Turkey, were monitored for pesticide residues. In green leafy vegetables, 363 pesticides were analyzed using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation, followed by liquid chromatography coupled to mass spectrometry (LC-MS/MS) for 311 residues and gas chromatography coupled to mass spectrometry (GC-MS/MS) for 52 residues. The method was in-house validated at two fortification levels, and satisfactory recoveries and precisions were achieved for all residues. No quantifiable residues were found in 35% of the samples, whereas 43 residues belonging to 24 different chemical classes were detected in 130 green leafy vegetables. Among the green leafy vegetables, the highest occurrence frequency was recorded in the rocket, followed by dill and parsley. In 46% of the green leafy vegetables, the residue levels exceeded European Union Maximum Residue Levels (EU MRLs). The most frequently detected pesticides were pendimethalin (22.5%), diuron (38.7%) and pymetrozine (52.5%) in dill, rocket and parsley, respectivelyÖğe Quantitation of aflatoxins in pistachios and groundnuts using HPLC-FLD method(Elsevier, 2014) Hepsağ, Fatma; Gölge, Özgür; Kabak, BülentIn this study, a sensitive high performance liquid chromatography coupled to a fluorescence detector (HPLC-FLD) method after post-column derivatisation was applied for the presence of aflatoxins (AFs) in 151 pistachios and 151 groundnuts from Turkey. Samples were collected between January 2010 and December 2012 in two provinces of Turkey and checked for AFs levels. Quantification limits were 0.11, 0.11, 0.12 and 0.14 ?g kg?1 for aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2), respectively. AFs were present in 14.6% of pistachios (22/151) and 19.2% of groundnuts (29/151) at total AFs levels ranging from 0.26 to 385 ?g kg?1 and from 0.16 to 60.9 ?g kg?1, respectively. Seven pistachio samples were above the European maximum tolerable limit (MTL) of 8 ?g kg?1 for AFB1, while total AFs concentration exceeded the MTL of 10 ?g kg?1 in eight pistachio samples. For groundnuts, eight and six samples exceeded MTL of 2 and 4 ?g kg?1 for AFB1 and total AFs, respectively.Öğe Validation of a modified QuEChERS method for the determination of 167 pesticides in milk and milk products by LC-MS/MS(Springer New York LLC, 2018) Gölge, Özgür; Koluman, Ahmet; Kabak, BülentA liquid chromatography tandem mass spectrometry (LC-MS/MS) method with modified QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction cleaning process was comprehensively validated for determination of 167 pesticide residues in three matrices: milk, cheese and cream. Optimisation of the mass spectrometry parameters was performed by injecting pesticide standard solutions into the electrospray ion (ESI) source. The mass spectrometer was operated in the positive ESI mode. The validation data fulfilled the requirements of the European SANTE/11945/2015 Guideline. The specificity of the developed method is considered satisfactory. Good linearity (R 2 > 0.99) was obtained for all pesticide matrix calibration curves within the range of 0.1–100 ?g kg?1. Mean recoveries of all target analytes ranged from 80.4 to 117.3%, and limits of quantification (LOQ) ranged from 1.1 to 13.1 ?g kg?1, depending on pesticide residues. The repeatability and within-laboratory reproducibility ranged from 0.2 to 15.1% and from 1.3 to 19.4%, respectively. The uncertainty was not higher than 48% for target analytes in the three matrices. The validated method was successfully applied to screening of milk and milk products, and none of the 167 pesticides investigated was detected in 92 real samples.
