Quick, Easy, Cheap, Effective, Rugged, And Safe Research Articles

Pesticide Residues in Mandarins: Three-Year Monitoring Results.

The demand of plant production product use has increased because of the current system of citrus production, which prioritizes high agricultural yields. Therefore, the monitoring of pesticide residues in citrus fruits and other agricultural products and their impacts on human health and food security are of great concern. This study aims to determine multi-class pesticides including highly polar residues in satsuma mandarins. A total of 226 mandarin samples were collected over three consecutive harvesting years from 2019 to 2021 in the Izmir region of Turkey. Targeted compounds included pesticides and metabolites with European Union (EU) regulatory levels, plus other non-approved residues and highly polar compounds. The residues excluding highly polar substances were analyzed by applying the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) determination for 434 analytes and gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) determination for 71 analytes. For six highly polar pesticides, sample preparation was based on Quick Polar Pesticides (QuPPe) extraction. The polar residues were determined by LC-MS/MS using internal standards. Forty different residues, including two highly polar substances, were recorded in mandarin samples through three harvesting years. In 8.4% of the samples, no quantifiable residues were detected, whereas 207 samples contained at least one residue. The maximum residue level (MRL) exceedances were recorded for 22.1% of the samples. The two most frequently found pesticides were phosphonic acid and spirotetramat, with an incidence rate of 48.7% and 46.5%, respectively. The concentration of phosphonic acid and spirotetramat in mandarin samples varied from 0.026 to 39.386 mg kg-1 and from 0.010 to 1.485 mg kg-1, respectively. The results will enable researchers and regulatory authorities to assess the extent of pesticide presence, identify potential risks, and take necessary measures to ensure the safety of satsuma mandarins for consumers.

A modified QuEChERS sample processing method for the determination of per- and polyfluoroalkyl substances (PFAS) in environmental biological matrices

QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample processing methods have previously been applied to a range of compounds and matrices. This study presents a modified QuEChERS sample processing method that was validated and employed for 24 per- and polyfluoroalkyl substances (PFAS) for various biological matrices. PFAS are a group of synthetic chemicals that have attracted substantial attention as some compounds are acknowledged to be persistent, toxic, and bioaccumulative. It is crucial to determine PFAS in diverse environmental matrices. Currently, limited sample processing methods for PFAS in biological matrices are available and the majority only focus on a few compounds such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). Thus, there is a demand to develop a sample processing method which is effective for many commonly tested PFAS compounds in environmental biological samples. In this study, the detailed sample processing procedures and method performance are described. The highlights of this method are:•The extraction solvent and salts were adjusted for PFAS extraction from environmental biological matrices.•The modified QuEChERS method is effective for extraction and cleanup from a variety of matrices including algae, plants, invertebrates, amphibians, and fish.

The effect of different decontamination processes on the residues of fipronil and its metabolites in chili fruits (Capsicum annuum L.).

Fipronil is a broad-spectrum phenyl pyrazole insecticide that has a high degree of environmental toxicity. Commonly available chilies in the market are treated with fipronil insecticides. Demand for insecticide-free chili has thus been increasing globally. This needs various sustainable and economical methods to remove insecticides from chilies. The present study examined the effectiveness of several cleaning methods to remove pesticide residues in chili fruits. A supervised field trial was conducted in randomized block design at Rajasthan Agricultural Research Institute, Durgapura, Jaipur, India. Chili samples were subjected to seven different household methods. The samples were extracted using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. The residues were analyzed using a gas chromatograph-electron capture detector and confirmed by GC-MS. Of the seven methods, the acetic acid treatment removes the maximum residue effect of fipronil and its metabolites (desulfinyl [MB046513]), sulfide (MB045950), and sulfone (MB046136) on chili fruits. By contrast, the tap water treatment was the least effective. The Food Safety and Standards Authority of India (FSSAI) have set the maximum residue limit value of 0.001 mg kg-1 for fipronil on green chili.

Monitoring and exposure assessment of ricinine in castor plant-based foods and dietary supplements

Ricinine, a toxic compound found in castor plants (Ricinus communis), causes abdominal pain, nausea, and vomiting. Castor leaves and castor oil-based dietary supplements are commonly consumed, but their ricinine content has not been evaluated for safety. This study aimed to determine the ricinine concentration in these products and to evaluate the ricinine exposure level from their consumption. The developed method combines the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) technique and liquid chromatography–tandem mass spectrometry (LC–MS/MS). A matrix-matched calibration method for castor leaves is then proposed, which demonstrates high linearity over a wide concentration range (50–1000 µg/kg; r2 > 0.995). The intraday and interday accuracies ranged from 93.6% to 113.7%; the precisions were within 10%. The limits of detection and quantitation were ≤ 8.9 µg/kg and ≤ 26.9 µg/kg, respectively, and this validated method was successfully applied to commercial castor plant-based products. Ricinine exposure from the consumption of these foods was estimated to be 0.0001–0.2792 µg/kg body weight/day. This study assesses the safety of castor plant-based food products and could help prevent potential health risks associated with ricinine consumption.

Simultaneous Analysis of 53 Pesticides in Safflower (Carthamus tinctorius L.) by Using LC–MS/MS Coupled with a Modified QuEChERS Technique

Objective: An optimized quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique was investigated and compared with the conventional QuEChERS technique for the simultaneous analysis of fifty-three pesticide residues in safflower using ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS). Method: Graphitic carbon nitride (g-C3N4) consisting of a major amount of carbon and nitrogen with a large surface area was used as a QuEChERS adsorbent instead of graphitized carbon black (GCB) for safflower extraction purification. Validation experiments were performed using spiked pesticide samples, and real samples were analyzed. Results: The linearity of the modified QuEChERS technique was evaluated with high coefficients of determination (R-2) being higher than 0.99. The limits of detection were <10 μg/kg. The spiked recoveries ranged from 70.4% to 97.6% with a relative standard deviation of less than 10.0%. The fifty-three pesticides exhibited negligible matrix effects (<20%). Thiamethoxam, acetamiprid, metolachlor, and difenoconazole were detected in real samples using an established method. Conclusion: This work provides a new g-C3N4-based modified QuEChERS technique for multi-pesticide residue analysis in complex food matrices.

Validation of a Method Scope Extension for Simple Biomonitoring of 353 Pollutants in Serum Samples

Animals and humans are exposed to various residues that can have a detrimental impact on health, including carcinogenic potential, endocrine disruption, or fatal toxicity. The toxic burden can be evaluated in several biological samples, with serum being one of the preferred and most convenient options. In this study, we have applied and validated a method for detecting several hundred toxins in serum samples. This technique involved a single-step QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction followed by analysis using gas and liquid chromatography coupled with mass spectrometry. With this methodology, we could detect and quantify up to 353 compounds, including persistent organic pollutants (POPs), pesticides, pharmaceuticals, and rodenticides, using just 250 µL of serum. Among them, 92% could be measured at concentrations below 1.25 ng/mL, making it ideal for biomonitoring. We applied this method to samples collected from camels (n = 40) and humans (n = 25). We detected naproxen, ketoprofen, paracetamol, levamisole, and some POPs in these samples. This study validated the ability to simultaneously detect a broad range of compounds in small volumes of serum.

Determination of pre harvest interval for selected pesticides in hyacinth bean in the agro-climatic conditions of Bangladesh

The present study was conducted to determine the pre harvest interval of chlorpyrifos and quinalphos in hyacinth bean in the agro-climatic condition of Bangladesh to ensure safe food for the consumers. A supervised field trial was undertaken in the experimental field of Entomology Division of BARI, Gazipur and the selected pesticides (chlorpyrifos and quinalphos) were sprayed with the recommended dose (1.5 ml/L of water). The samples were collected at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 12 days after spray (DAS). The collected samples were extracted and cleaned up using modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and the residues were determined by Gas Chromatography (GC) coupled with Flame Thermionic Detector (FTD). The residue of chlorpyrifos was detected upto 8 DAS (0.027 mg/Kg) at a level above the EU-MRL, and at 9 DAS, no residue was detected. So, the PHI for chlorpyrifos was set at 9 DAS. On the other hand, the residue of quinalphos was detected upto 9 DAS, of which the level of residue was above EU-MRL upto 8 DAS (0.02 mg/kg). At 9 DAS, the quinalphos residue remained 0.009 mg/Kg, which was below EU-MRL. So, the PHI for quinalphos was set at 9 DAS. Asian Australas. J. Food Saf. Secur. 2023, 7 (1), 47-55

Analysis of cyantraniliprole residues in beetroot and beet top using LC-MS/MS, dietary exposure assessment, and evaluation of decontamination techniques.

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was standardized for the analysis of cyantraniliprole residues in beetroot and beet top (Beta vulgaris ssp. vulgaris L.) using liquid chromatography-mass spectrometry/mass spectrometry. Samples were extracted with acetonitrile and cleaned up by dispersive solid phase extraction. Acceptable recovery of 84.74%-104.24% for beetroot and 80.19%-118.55% for beet top matrix was achieved at fortification levels ranging from 0.02 to 0.025μg g-1 , with relative standard deviation<20% that signified the application of the method for detecting cyantraniliprole residues. A field experiment was conducted to determine the half-life and preharvest interval for cyantraniliprole residues in beetroot and beet top. The half-life obtained was 1.86-2.7 days for beetroot and 3.65-5.33 days for beet top. The preharvest interval calculated was 9.12-12.90 and 22.12-37.98 days for beetroot and top, respectively. The dietary exposure assessment at studied doses found cyantraniliprole residues below acceptable daily contact limits. Among different decontamination techniques evaluated, peeling + tap water washing resulted in a higher reduction of residues while cooking and juicing resulted in moderate removal of residues.

UHPLC-MS/MS phytochemical screening, polyphenolic content and antioxidant potential of Diplorhynchus condylocarpon (Müll.Arg.) Pichon (Apocynaceae), a medicinal plant

Diplorhynchus condylocarpon (Müll.Arg.) Pichon (Apocynaceae) leaves, stem bark, and roots are commonly used as popular folk medicine in Zambia and other African countries. This work aimed to find out the broad categories of phytocompounds present in the plant, screen the polyphenols, and assess the total polyphenolic content and the antioxidant activity of methanolic extracts of leaf, stem bark, and roots. Maceration was used to extract secondary metabolites for preliminary phytochemical screening. QuEChERS (quick, easy, cheap, effective, rugged, and safe), based technique was used to recover polyphenols for liquid chromatography with tandem mass spectrometry (LC-MS/MS) screening. Standard chemical tests were used for preliminary phytochemical screening. Total phenolic content (TPC) was evaluated using the Folin-Ciocalteu (FC) method at 765 nm. Total flavonoid content (TFC) was evaluated by the aluminum chloride colorimetric assay at 510 nm. Antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method at 517 nm. The preliminary phytochemical screening revealed the presence of antioxidants, polyphenols, and other valuable phytocompounds such as alkaloids, saponins, and terpenoids. The LCMS/MS polyphenolic screening revealed the presence of mainly polyphenolic metabolites. TPC values were higher in the leaf (171.099±0.515 mg GAE/g) and root (88.8093±3.156 mg GAE/g) than in the stem bark (71.061±0.515 mg GAE/g) extracts. Further, the leaf extract contained 129.402±0.407, the root contained 64.672±0.813, and the stem bark had 37.643±0.704 mg QE/g total flavonoids. The leaf extract exhibited in a dose-dependent manner higher DPPH radical scavenging activities (34.250, 50.625, 66.562, 81.406, and 97.344%), followed by the root (16.406, 31.406, 50.781, 65.625, and 82.188%), and the stem bark extract only had the least DPP quenching activities (15.469, 27.969, 40.469, 52.500, and 68.590%) for the concentration of 20, 40, 60, 80 and 100 µg/mL respectively. Further, the results from the DPPH assay show that the leaf extract had the best IC50 value of 19.973 µg/mL, followed by the root extract with 60.867 µg/mL, and the stem bark extract with 107.150 µg/mL. These antioxidant activities support the traditionally claimed therapeutic benefits of D. condylocarpon leaves, stem bark, and roots in the treatment of oxidative stress-related disorders such as diabetes mellitus, chronic wounds, and diarrhea. This study may lead to the production of new herbal medicines using D. condylocarpon.

Optimization of modified QuEChERS method for extraction of selected pharmaceuticals from vegetable samples using HPLC

&#x0D; ABSTRACT. Optimized QuEChERS (quick, easy, cheap, effective, rugged and safe) method of sample preparation was employed for five selected pharmaceutical compounds on its advantage of simplicity, less extraction solvent and extraction time. Different parameters affecting the extraction efficiency of the target analyte was optimized. Since QuEChERS was developed for pesticides, uses of the method for pharmaceuticals need modification and evaluation of different parameters. Clean-up sorbents were evaluated for their matrix effect removal after extraction and a combination of d-SPE sorbent, MgSO4, PSA, C18 and diatomaceous earth found to be selective clean-up sorbent for the targeted compounds. The addition and amount of diatomaceous earth and EDTA during the clean-up and extraction steps, respectively, were also examined and the amount was optimized. Solvent type and composition, salt type and extraction time were also optimized and methanol, MgSO4 with NaCl salt and 5 min extraction time was obtained. The method was successfully applied to different vegetable samples collected from Addis Ababa, Ethiopia and Johannesburg, South Africa (carrot, cabbage and lettuce) and none of the target analytes were found in the sample investigated. The matrix effect study on vegetable samples collected was found very high that suppresses the signal during analysis.&#x0D; &#x0D; KEY WORDS: QuEChERS, EDTA, Pharmaceuticals, Vegetable, HPLC&#x0D; Bull. Chem. Soc. Ethiop. 2023, 37(4), 831-844. &#x0D; DOI: https://dx.doi.org/10.4314/bcse.v37i4.3

Development, validation, and use of a monitoring method for fipronil and its metabolites in chicken eggs by QuEChERS with online-SPE-LC-Q/Orbitrap analysis.

The residues of fipronil and its metabolites in chicken eggs pose a threat to human health, so regular monitoring is necessary. However, the pretreatments of the existing detection methods are complex and time-consuming. A simple and streamlined pretreatment method is needed to improve the detection efficiency. A rapid, efficient, and facile approach employing QuEChERS with online solid-phase extraction liquid chromatography tandem Q-Exactive Orbitrap high resolution mass spectrometry (online-SPE-LC-HRMS) was established and evaluated for the determination of fipronil, fipronil-desulfinyl, fipronil-sulfone and fipronil-sulfide in chicken eggs. An improved sample preparation technique combining QuEChERS and online-SPE was developed. Negative targeted ion fragmentation scanning (t-MS2 ) and targeted-selected ion monitoring (t-SIM) of the HRMS were adopted to identify and quantify the target analytes. The proposed pretreatment method took a few steps in < 13 min to achieve excellent recoveries and negligible interference. High selectivity was acquired with the adoption of Q/Orbitrap HRMS. The LOQ of the analytes was 2.5 μg kg-1 , meeting the detection requirements of the MRL enacted by the Codex Alimentarius Commission (CAC), Japan and USA for the sum of fipronil and its metabolites. Extraction recoveries at three spiked concentration levels were within 84.56-93.84% with RSD ≤ 5.87%. The established method is efficient and easy to operate and displays satisfactory LOQs, recoveries, accuracy and precision. This approach serves as a reference method for monitoring eggs while providing potential solutions for fipronil determination in more complicated matrices.

Assessment of various conditions for the simultaneous determination of US EPA and EU priority PAHs in coffee samples and their PAHs consumption risk

The optimal conditions for simultaneous determination of the U.S. Environmental Protection Agency (US EPA) and European Union (EU) priority polycyclic aromatic hydrocarbons (PAHs) in coffee beans and coffee brews were developed. The QuEChERS (quick, easy, cheap, effective, rugged and safe) technology combined with high performance liquid chromatography - temperature-controlled fluorescence detection and gas chromatography - tandem mass spectrometry were used in the investigation. PAHs could be determined in commercially available green coffee beans (possibly caused by environmental contamination), and their PAHs content increased with the degree of roasting. Coffee beans brewed with the coffee machine released more PAHs into their brews than those brewed with the drip bag. The PAHs consumption risk of the brewed coffee samples was not high due to their low PAH level. Nevertheless, the methods of roasting and brewing and the amount of drinking could still be considered to reduce the intake of PAHs.

Residue Determination Method and Photolysis Process of Picoxystrobin in Three Soils by QuEchers and HPLC/MS

ABSTRACT The dissipation and residue of picoxystrobin in three different soils (Xerosols, Yermosols and Chernozem) was investigated. An easy-to-implement and sensitive method was established to determine picoxystrobin in the three different soils via modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) combined with HPLC (high-performance liquid chromatography). The photodegradation process of picoxystrobin in three different soils was detected by HPLC-mass spectrometry. The linearity of picoxystrobin detection was studied in the range of 0.3–10 mg/L (0.3, 0.5, 1, 2 and 10 mg/L), good linearity was obtained and the correlation coefficients (R2) was 0.9999. The recoveries of picoxystrobin ranged from 78.4% to 106.4% and relative standard deviation of 0.67%-4.46% in three kinds of soil spiked at 0.5, 1, and 2 mg/kg. The results of the recovery study indicated that the method meets the precision and accuracy requirements for picoxystrobin in the three different soils. The photodegradation experiments revealed that the compound had a degradation half-life ranging from 3.80–4.29 days. The rule of photodegradation of picoxystrobin on the surface of three soils was consistent with first-order reaction kinetic model. Finally, two possible routes of picoxystrobin fragmentation were indicated by mass spectrometry. This work will provide a theoretical reference for the analysis of picoxystrobin residues in soil and practical applications.

Behavior of trifloxystrobin and propineb as combi-product in tomato (Solanum lycopersicum) and their risk assessment for human health.

Fungicides have their own unique characteristics and modes of action; a combination formulation of trifloxystrobin and propineb was applied to tomatoes for their dissipation kinetics and to ensure consumer safety. The combi-product was applied at a 10-day interval with standard (61.25 + 1072.75 g a.i. ha-1 ) and double (122.5 + 2145.50 g a.i. ha-1 ) doses. The efficient analytical method was established using the QuEChERS approach followed by liquid chromatography-mass spectrometry. The maximum residue levels of 0.15 and 0.35 mg kg-1 of trifloxystrobin were detected in tomato fruits immediately after application at standard and double doses, respectively. The corresponding levels of propineb as carbon disulfide were 0.47 and 0.90 mg kg-1 , respectively. Considering trifloxystrobin (0.7 mg kg-1 ) codex MRL and propineb as dithiocarbamate (3.0 mg kg-1 ) EU-MRL in tomato, a PHI of 1 day can be proposed. The anticipated residue contributions of both fungicides were far less than the acceptable daily intake. The targeted hazard quotient and hazard index were also less than one for both fungicides. Furthermore, the theoretical maximum residue contribution was less than its maximum permissible intake, which indicates that the consumption of tomatoes containing the measured value of each fungicide residue could not pose any health risks.

Determination and risk assessment of 31 pesticide residues in apples from China's major production regions

The presence of pesticide residues in apple fruit raises serious health concerns. In multi-residue pesticide analysis, the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method has gradually replaced less efficient traditional extraction methods. This study developed a modified QuEChERS method coupled with ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) to simultaneously detect the residue of multiple pesticides in apple fruit. The method exhibited high linearity (R2 ≥ 0.99), and excellent recoveries (74.4–118.1 %) for 31 pesticides with relative standard deviations below 20 %. The limit of detection and limit of quantification were 0.1–4.0 μg/kg and 2.0–10.0 μg/kg, respectively. By using the established method, 20 pesticides were detected in 152 'Fuji' apple samples collected from the orchards of 17 cities in two major apple production regions of China, with an overall detection rate of 58.6 %. The residue levels were below the maximum levels set by GB 2763–2019. Moreover, both the chronic dietary intake risk (%ADI) and the acute dietary intake risk (%ARfD) for all the detected pesticides were lower than 100 %, indicating that the dietary intake risks are acceptable and would not pose potential health risks.

Quantitative determination of polychlorinated biphenyls in chicken based on QuEChERS extraction and GC-MS/MS detection

Polychlorinated biphenyls (PCBs), a class of synthetic organic compounds consisting of chlorine atoms on two coupled biphenyl rings, have been declared class A carcinogens by the World Health Organization. Here, we report a new method for the determination of PCBs content in chicken. The method employs QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction, followed by gas chromatography and tandem mass spectrometry (GC-MS/MS) detection for the identification and quantification of seven indicative PCBs (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, PCB180). The PCBs were extracted by acetone with an Association of Official Analytical Chemists (AOAC) extraction kit, followed by a clean-up step using primary secondary amine, octadecyl silica, florisil, and anhydrous magnesium sulfate. PCBs in the extracts were subsequently quantified by GC-MS/MS. The method was validated, and the correlation coefficients of the curves were found to be higher than 0.99. The limits of detection for the seven indicative PCBs ranged from 0.1 to 0.5 ng/g, and the limits of quantification were 0.3–1.5 ng/g. Satisfactory recovery rates ranged from 96% to 115%, with a maximum relative standard deviation of 9%. For simple pretreatment and accurate detection, this method is quick and efficient in detecting batches of seven indicative PCBs in chicken.

Monitoring of pesticide residues in yard long bean collected from Mymensingh district of Bangladesh

The farmers of our country mostly depend on chemical pesticides for crop protection due to the scarcity of competent pesticide alternatives and enough knowledge of safe pest management. As a result, there is a great possibility to remain residues in the harvested crops. Keeping this view, this study was conducted to analyze organophosphorus pesticide residues in yard long bean collected from five local markets of Mymensingh district of Bangladesh. The collected samples were carried to the Pesticide Analytical Laboratory, Entomology Division of Bangladesh Agricultural Research Institute (BARI), Gazipur on the same sampling day. The collected samples were analyzed using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and Gas Chromatography (GC) coupled with Flame Thermionic Detector (FTD). Among the 30 samples of yard long bean, 3 samples (10% of the total samples) contained residue of quinalphos, of which 2 samples contained quinalphos residue above MRL. This study reflects the overall scenario of pesticide residue remain in the harvested yard long bean collected from local markets of Mymensingh city. Therefore, monitoring of pesticide residues in vegetables should be strengthened. Asian Australas. J. Biosci. Biotechnol. 2023, 8 (1), 8-16

Quantification of PFAS in Oyster Tissue Using a Rapid QuEChERS Extraction Followed by UPLC-MS/MS Analysis

Per- and poly-fluoroalkyl substances (PFAS) are a large group of man-made chemicals that repel oil, stains, grease, and water and are fire resistant. PFAS are known to be persistent in the environment and bioaccumulate in human and animal tissue, soil, and water. To mitigate human exposure to these chemicals, PFAS analysis by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was used to monitor their presence in the environment. This study focused on analyzing oysters harvested from coastal New England for 14 PFAS. The validated method addressed in this study utilized a quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach using various sorbents and showed that the combination of primary secondary amine/graphitized carbon black (PSA/GCB) provided the most effective sample clean-up prior to analysis. The recoveries for the targeted analysis ranged from 61% to 116.3% with relative standard deviations from 2.4% to 13.3% at the 125.0 ng mL−1 analyte level. The method detection limits were from 0.33 ng g−1 to 6.75 ng g−1. In a targeted analysis of five unknown samples, two samples had a detectable level of the legacy compound, perfluorooctanesulfonic acid (PFOS).

Simplified QuEChERS technique followed by UHPLC-MS/MS analysis for the determination bisphenol A in whole and powdered milk

Bisphenol A (BPA), an important endocrine disruptor, is employed in the manufacturing of many materials such as food packaging. The ingestion of contaminated food is considered the most relevant form of exposure to this compound. Data concerning the presence of this contaminant in milk in Brazil, however, are still lacking. In this context, an analytical method for the determination of BPA in ultrahigh temperature (UHT) milk, pasteurised milk, and milk powder was developed. A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was used for sample treatment, and BPA was determined by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The method was selective for BPA in all investigated milk samples. No matrix effects were observed, thus indicating that calibration curves could be prepared in solvent for routine analysis. The method presented satisfactory accuracy, with recovery values between 78 and 94%. Relative standard deviation values obtained in the repeatability (11%) and intermediate precision (4.8%) studies were also satisfactory (HorRatr and HorRatR values less than 2). The analyte limits of detection and quantification were 0.12 and 0.36 ng/g for while milk, and 0.40 and 1.20 ng/g for reconstituted milk powder (1:10), respectively, and the sensitivity of the analytical method was considered adequate for the purpose of the present work.

Determination of 355 Pesticides in Lemon and Lemon Juice by LC-MS/MS and GC-MS/MS.

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.