Evaluation of Alternaria mycotoxins in strawberries: quantification and storage condition

Alternariol (AOH), alternariol methyl ether (AME) and tentoxin (TEN) are Alternaria mycotoxins produced by the most common post-harvest pathogens of fruits. The production of these metabolites depends on several environmental factors, mainly temperature, water activity, pH and the technological treatments that have been applied to the product. In this study, the occurrence of AOH, AME and TEN was evaluated in strawberries samples stored at different temperatures ranges (at 22 ± 2 or 6 ± 2°C) and different periods (up to 1 month) simulating the current practice of consumer’s storage conditions. Sample extraction was performed using a liquid–liquid extraction method prior to LC-MS/MS analysis. AOH was the most prevalent mycotoxins with a 42% at strawberries stored at (22 ± 2)°C and 37% stored at (6 ± 2)°C. The highest AOH levels were found in samples conserved at (22 ± 2)°C ranging between 26 and 752 ng g^–1. AME levels ranged between 11 and 137 ng g^–1, which were found mainly in stored samples at (6 ± 2)°C for more than 28 days. None sample presented levels of TEN in either of the studied conditions.     

Rapid determination of Alternaria mycotoxins in tomato samples by pressurised liquid extraction coupled to liquid chromatography with fluorescence detection

ABSTRACT

A sensitive and reliable method using pressurised liquid extraction (PLE) followed by molecularly imprinted solid phase extraction (MISPE) and high performance liquid chromatography with fluorescence detection (HPLC–FLD) has been developed for the analysis of alternariol (AOH) and alternariol monomethyl ether (AME) in tomato samples. Influence of several extraction parameters that affect PLE efficiency were evaluated for the simultaneous extraction of both mycotoxins in the selected samples. AOH and AME were optimally extracted using MeOH/water (25:75, v/v) at 70°C as solvent, a pressure of 1000 psi and a single extraction cycle. The resulting PLE extracts were pre-concentrated by molecularly imprinted solid phase extraction (MISPE) cartridges followed of analysis by HPLC with fluorescence detection (λ_exc = 258, λ_em = 440 nm). The proposed method was applied to the analysis of AOH and AME in fortified tomato samples (20–72 µg· kg–1) with recoveries of 84–97% (RSD < 8%, n = 6) for AOH and 67–91% (RSD < 13%, n = 6) for AME. The detection limit for AOH and AME were 7 and 15 µg· kg^–1, respectively. The ensuing PLE–MISPE–HPLC–FLD method was validated for the analysis of both mycotoxins in tomato samples in accordance with European Commission Decision 2002/657/EC.     

Occurrence of emerging mycotoxins in cereals and cereal-based products from the Korean market using LC-MS/MS

The present study aimed to investigate the occurrence of emerging mycotoxins in cereals (n = 61) and cereal-based products (n = 36) collected from Korean market. First of all, using the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method, and ultrahigh-pressure liquid chromatography (UPLC) with triple quadruple tandem mass spectrometry (MS/MS), we developed a simple and fast method for quantitative determination of eight emerging mycotoxins including alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), beauvericin (BEA) and enniatins (ENs; ENA, ENA1, ENB and ENB1). The developed analytical method was validated in parameters of linearity, precision and accuracy. For UPLC-MS/MS analysis, the recoveries of emerging mycotoxins from spiked samples at three concentration levels ranged from 82.7% to 108.8% with RSDs between 0.4% and 14.7%. Analytical methods were applied to determine the contamination of mycotoxins in cereal and cereal-based product samples. Sixty-three of the total 97 samples were contaminated with at least one emerging mycotoxin. The maximum number of emerging mycotoxins observed in a single sample was six out of eight analytes. The highest level of contamination was detected in cereal at 70.9 μg/kg for alternariol monomethyl ether (AME). However, currently there is no international standard for emerging mycotoxins in food. Accordingly, it is necessary to establish a database of emerging mycotoxins contamination through continuous monitoring.     

Alternaria toxins in Argentinean wheat,bran, and flour

Alternaria species have been reported to infect a wide variety of vegetables, fruits, and cereal crops. Wheat is one of the most consumed cereal worldwide. A sensitive HPLC-DAD methodology was applied to quantify alternariol (AOH), alternariol methyl ether (AME) and tenuazonic acid (TeA) in 65 samples of whole wheat, bran, and flour. The extraction methodology allowed extracting the three toxins simultaneously. Limits of detection in wheat were 3.4, 4.5, and 0.5 µg kg^?1 for AOH, AME and TeA, respectively. For bran, these data were 3.1, 4.5, and 12 µg kg^?1 and for flour 50, 70, and 14 µg kg^?1, respectively. The studied recoveries were higher than 70% and RSD was below 10%. Wheat and bran samples showed low AOH and AME contamination compared to TeA. The averages levels found for TeA in wheat, bran and flour were 19,190, 16,760, and 7360 µg kg^?1, respectively.     

Dispersive Liquid-Liquid Microextraction for the Determination of Emerging <Emphasis Type="Italic">Fusarium</Emphasis> Mycotoxins in Water

A new method was optimized for the determination of emerging Fusarium mycotoxins enniatins (ENs) and beauvericin (BEA) in different types of water. Mycotoxin analysis was performed by dispersive liquid-liquid microextraction (DLLME) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Mycotoxins were efficiently extracted from water into carbon tetrachloride by DLLME technique using acetonitrile as disperser solvent. Detection limits were in the range of 0.06–0.17 μg L^?1. Quantification was performed using matrix-matched calibration curves over a linear range from limit of quantification (LOQ) to 200 μg L^?1. Acceptable recoveries were obtained between 78.5 and 100.1 % with relative standard deviations of <14 %. The proposed method may be advised as an easy, sensitive, and accurate method for determining emerging Fusarium mycotoxins in water. The method was successfully applied to the analysis of different kinds of water. No detectable levels were achieved in surface, ground, tap, and bottled water. Concentration levels up to 50 μg L^?1 were detected in cooking water related to the pasta cooking process.     

自制固相萃取柱-超高效液相色谱-串联质谱法同时测定果蔬中的8 种真菌毒素

建立基于自制固相萃取柱的样品净化-超高效液相色谱-串联质谱同时测定果蔬中8 种主要真菌毒素的方法,包括链格孢毒素、展青霉素、赭曲霉毒素A及橘青霉素。样品经80%乙腈溶液提取、离心后,通过自制固相萃取柱（HLB＋MCX）排除杂质干扰,流出液经氮吹至近干后,直接用超高效液相色谱-串联质谱进行测定,基质外标法定量。在较宽的线性范围内,8 种毒素的线性相关系数（r2）均不小于0.99,定量限为1～5 μg/kg,在3 个不同添加水平下的加标回收率为76.0%～102.7%,相对标准偏差为0.8%～4.7%。该法灵敏度高,操作简单﹑快速,适用于苹果、樱桃和番茄等果蔬中痕量真菌毒素的测定。     

Multitoxin evaluation in fermented beverages and cork stoppers by liquid chromatography–tandem mass spectrometry

A total of twenty‐eight mycotoxins were surveyed in wine (red, white and rose), cider (white and rose) and their cork stoppers from eight countries. Toxins of different fungi genera were detected as follows: Alternaria (ATs: alternariol – AOH; alternariol methyl – AME) and Penicillium/Aspergillus (ochratoxin A – OTA; penicillic acid – PAC). Toxins and levels varied with the sample types and country of origin. Wine presented contamination of OTA, AOH and AME. OTA was detected in forty‐one wine samples with levels ranging from 0.01 to 0.86 μg L^?1, below EU legislation. AOH and AME were detected in thirty‐three and eight of wines samples, respectively, at levels from 0.2 to 13.3 μg L^?1, while no contamination was detected in ciders up to the method LOQs. Regarding the cork stoppers toxins detected, they were AOH, AME and PAC. Corks of red wine from different countries had levels of OAH and AME ranging from 5.0 to 101.0 and 2.5 to 5 μg g^?1, respectively. It is necessary to pay more attention on the corks processing and cork type used in the bottles as, different from the ordinary ones, the ground bark and compressed type did not have toxins detected.     

High-Throughput Analytical Strategy Based on Modified QuEChERS Extraction and Dispersive Solid-Phase Extraction Clean-up Followed by Liquid Chromatography-Triple-Quadrupole Tandem Mass Spectrometry for Quantification of Multiclass Mycotoxins in Cereals

A simple, reliable, efficient, selective and sensitive QuEChERS-based (quick, easy, cheap, effective, rugged and safe) sample preparation strategy, involving an initial partitioning step using acidified acetonitrile (ACN), MgSO₄, NaCl and citrate buffer salts, combined with dispersive solid-phase extraction (d-SPE) clean-up, is proposed for the simultaneous multiclass mycotoxins quantification, including aflatoxins, ochratoxins, fumonisins, trichothecenes and zearalenone, in cereals. The final clear extracts were concentrated under vacuum to near dryness and taken-up with the initial mobile phase (MeOH:H₂O;70:30, v/v) previous to reversed-phase liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) analysis. Careful optimization of the LC-ESI-MS/MS parameters was achieved in order to attain a fast separation and increased sensitivity. The detection was carried out on a triple-quadrupole tandem mass spectrometry (MS/MS) by electrospray ionization in positive ion mode (ESI⁺) with multiple reaction monitoring (MRM). Tandem MS conditions were optimised in order to increase selectivity, selecting the best transitions (parent ion to quantifier and qualifier ions) for quantification and identification. The performance of the method was assessed and compared to European Commission (EC) Regulations, by studying the selectivity, specificity, limits of detection (LOD) and quantification (LOQ), linear dynamic range (LDR), matrix effect, accuracy, precision, and uncertainty. Good linearity (r ²?>?0.9713) was achieved for all mycotoxins investigated, and LODs (S/N?=?3) and LOQs (S/N?=?10) were below the tolerance levels of mycotoxins set by EC. Recoveries of the extraction process, obtained with different spiked concentrations, ranged from 72.9 to 120.6 %, with relative standard deviations (RSD) lower than 23.0 %. Only in 6 % of all combinations did the RSD values exceed 15 %. Matrix effects were observed by comparing the slope of matrix-matched standard calibration with that of the solvent. The developed method was applied to evaluate the co-occurrence of multiclass mycotoxins in cereals collected at the importation points and consumer habitations at Madeira Island. Samples collected at importation points (15 wheat samples, 4 maize samples and 2 rice samples) showed the presence of DON in three wheat samples, and FB1 and HT-2 in one wheat sample. Three maize samples were detected with FB1 (two samples) and AFG₂ (one sample) whereas one rice sample was detected with ZEN. The results revealed the absence of target mycotoxins on the rice samples collected at consumer habitations. None of the studied cereal samples exceeded the maximum permissible limits or indicative levels set by the EC which means that the particular Madeira Island subtropical climate conditions do not represent a major risk for cereal contamination, taking into account the investigated mycotoxins.     

Ion-Pair-Based Air-Assisted Liquid–Liquid Microextraction for the Extraction and Preconcentration of Phthalic Acids from Aqueous Samples

In the present study, a rapid, simple, and highly efficient sample preparation method based on ion-pair air-assisted liquid–liquid microextraction using a low-density extraction solvent followed by high performance liquid chromatography–diode array detection has been developed for the extraction, preconcentration, and determination of three phthalic acids (phthalic acid, iso-phthalic acid, and terephthalic acid) in aqueous samples. In this method, a mixture of tri-butyl amine (as an ion-pair reagent) and toluene (as an extraction solvent) is transferred into an aqueous sample solution. Fine organic solvent droplets are formed by aspirating and dispersing of the mixture via syringe needle. After that, the formed ion-pairs are extracted into toluene, and after centrifuging, the obtained collected phase is transferred into a microtube and is evaporated to dryness under a stream of nitrogen at room temperature. The residue is re-dissolved in mobile phase and injected into the separation system for analysis. Under the optimum extraction conditions, the method showed low limits of detection and quantification between 0.09–0.24 and 0.29–0.78 ng mL^?1, respectively. Extraction recoveries and enrichment factors were from 88 to 98 % and 443 to 491, respectively. Relative standard deviations for the extraction of 5 ng mL^?1 of each analyte were less than 8.4 % for intra-day (n?=?6) and inter-days (n?=?5) precisions. Finally, different aqueous samples were successfully analyzed using the proposed method, and the target analytes were determined in some of them at ng mL^?1 level.     

Production of alternariol and alternariol methyl ether by Alternaria alternata grown on fruits at various temperatures

Two toxigenic strains of the fungus Alternaria alternata (ATCC 56836 and ATCC 66868) were grown on surface-disinfected, fresh, ripe fruits and tested for the production of alternariol (AOH) and alternariol methyl ether (AME). Examined fruits included strawberries; red and green seedless grapes; concord grapes; red delicious, golden delicious, and gala apples; and blueberries. After inoculation, fruits were incubated at 4, 10 degrees C, or room temperature (approximately 21 degrees C) for up to 3 weeks. At weekly intervals, duplicate samples were analyzed for AOH and AME by using liquid chromatography. Results indicated that A. alternata and its metabolites were not a major problem in strawberries due to the presence of fast-growing molds like Rhizopus and Botrytis that outgrew and possibly inhibited Alternaria. Both Alternaria strains showed limited growth on apples, although fast-growing molds were not present after surface disinfection; AOH and AME were produced only by the ATCC 56836 strain on the golden delicious and gala varieties, (ranging from <0.1 to 5 microg/g and <0.1 to 14 microg/g for AOH and AME, respectively). Restricted growth of both strains without toxin production occurred in blueberries, whereas moderate growth and AOH (<0.1 to 3,336 microg/g) and AME (<0.1 to 1,716 microg/g) production took place in grapes.     

Development of an Indirect Competitive ELISA for Analysis of Alternariol in Bread and Bran Samples

Alternariol (AOH) is one of the major mycotoxins produced by various species of Alternaria fungi. Natural occurrences of AOH have been reported in various foods, including fruits; processed fruit products such as apple juice, tomato products; wheat and other grains; oilseeds and products thereof, such as sunflower seeds, oilseed rape meal, and flax seed/linseed; and pecans. In this study, AOH-specific polyclonal antibodies were generated and developed an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for monitoring AOH in bread and bran samples. The assay was very sensitive with a limit of detection (LOD) of 2.4?±?0.6 ng/g and a half maximal inhibitory concentration (IC₅₀) of 15.2?±?2.6 ng/g in bread and a LOD of 8.4?±?1.2 ng/g and IC₅₀ of 52.8?±?10.8 ng/g in bran extract. The assay was very specific to AOH and showed no cross-reactivity to alternariol monomethyl ether, altertoxin, altenuene, tentoxin, or tenuazonic acid. The effect of organic solvents on the assay was tested. The ELISA system tolerated methanol and acetonitrile as co-solvents at up to 5% content without significant loss of IC₅₀ value. Recoveries in all cases were greater than 75%, and the results using this method were comparable to those obtained from mass spectrometry methods. We conclude that this method is suitable for rapid detection of AOH in bread and bran samples, without expensive analytical equipment or time-consuming sample preparation.     

Alternaria toxins in wheat from the Autonomous Province of Vojvodina,Serbia: a preliminary survey

Although Fusarium species remain a main source of mycotoxin contamination of wheat, in recent years, due to the evident climatic changes, other mycotoxigenic fungi have been recognised as important wheat contaminants. Alternaria species, especially A. alternata, have been found as contaminants of wheat as well as wheat-based products. Under favourable conditions A. alternata very often produce alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA) and others Alternaria toxins. The aim of the present study was to examine the presence of three Alternaria toxins (AOH, AME and TeA) in wheat samples harvested during three years (2011–13). To this end, 92 samples were collected during wheat harvesting from different growing regions of the Autonomous Province of Vojvodina, which represents the most important wheat-growing area in Serbia. The presence of Alternaria toxins was analysed by HPLC with electrospray ionisation triple quadrupole mass spectrometry (LC-ESI-MS/MS). Among all the analysed wheat samples, 63 (68.5%) were contaminated with TeA, 11 (12.0%) with AOH and 6 (6.5%) with AME. Furthermore, the maximum and mean toxin concentrations were 2676 and 92.4 µg kg^?1, 48.9 and 18.6 µg kg^?1, and 70.2 and 39.0 µg kg^?1 for TeA, AOH and AME, respectively. Co-occurrence of three Alternaria toxins in wheat samples was detected in six samples; a combination of two toxins was found in two samples; and 64 samples contained one toxin. The results showed that among 92 analysed wheat samples, only 20 (21.7%) samples were without Alternaria toxins. The presence of Alternaria toxins was also investigated in terms of weather conditions recorded during the period of investigation, as well as with the sampling region. This study represents the first preliminary report of the natural occurrence of Alternaria toxins in wheat (Triticum aestivum) from Serbia.     

Novel oxidative in vitro metabolites of the mycotoxins alternariol and alternariol methyl ether

The Alternaria toxins alternariol (AOH; 3,7,9-trihydroxy-1-methyl-6H-benzo[c]chromen-6-one) and alternariol methyl ether (AME, 3,7-dihydroxy-9-methoxy-1-methyl-6H-benzo[c]chromen-6-one) are common contaminants of food and feed, but their oxidative metabolism in mammals is as yet unknown. We have therefore incubated AME and AOH with microsomes from rat, human, and porcine liver and analyzed the microsomal metabolites with HPLC and GC-MS/MS. Seven oxidative metabolites of AME and five of AOH were detected. Their chemical structures were derived from their mass spectra using deuterated trimethylsilyl (TMS) derivatives, and from the information obtained from enzymatic methylation. Several of the metabolites were identified by comparison with synthetic reference compounds. AME as well as AOH were monohydroxylated at each of the four possible aromatic carbon atoms and also at the methyl group. In addition, AME was demethylated to AOH and dihydroxylated to a small extent. As the four metabolites arising through aromatic hydroxylation of AME and AOH are either catechols or hydroquinones, the oxidative metabolism of these mycotoxins may be of toxicological significance.     

Simultaneous Determination of Eight Tranquilizers in Pork by Ultra-Performance Liquid Chromatography Coupled with Electrospray Tandem Mass Spectrometry

An ultra-performance liquid chromatography/electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated for quantification of eight tranquillizers (chlorpromazine, imipramine hydrochloride, diazepam, nitrazepam, nordazepam, oxazepam, flurazepam, and haloperidol) in pork. Sample pretreatment consisted of extraction by acetonitrile, defatted by n-hexane, and further solid phase extraction by hydrophilic-lipophilic balance (HLB) extraction cartridges. The triple quadrupole mass spectrometer was operated in positive ion mode, and multiple reaction monitoring was used for drug quantification. The method was validated over the concentration ranges of 1.0 ～ 250 μg kg^?1 for the eight tranquillizers. The calibrations were performed in sample matrices, and the interference effect of sample matrices on the ionization was effectively eliminated. Good linear relationship (R ² > 0.99) was observed within the concentration range of 1.0–250 μg kg^?1. The average recoveries of the eight tranquillizers spiked at three levels ranged from 63.7 to103.2 % with the relative standard deviation below 11.8 %. The limits of detection were between 0.06 and 0.30 μg kg^?1, and the limits of quantification were between 0.2 and1.0 μg kg^?1 for all analytes in pork. This validated method has been successfully used to quantify the concentration of the eight tranquillizers in pork samples.     

Mycotoxin production by Alternaria strains isolated from Argentinean wheat

The toxigenic potential of Alternaria strains isolated from Argentinean wheat was investigated. A total of 123 strains were assayed for the production of tenuazonic acid (TA), alternariol (AOH) and alternariol monomethyl ether (AME). All but one of the isolates were able to produce at least one of the three mycotoxins. TA was produced by 72% of the strains (1-14782 mg/kg), AOH by 87% (4-622 mg/kg) and AME by 91% (7-2625 mg/kg). The average level of TA detected for all strains (1757 mg/kg) was higher than the average level of both alternariols (162 mg/kg for AOH and 620 mg/kg for AME). TA was the toxin produced at the highest concentration but in lower frequency. Most of the strains were able to synthesize more than one toxin: 74 isolates (60%) were positive for all three toxins, 30 (24%) for both AOH and AME, 5 (4%) for both TA and AME, and 2 (2%) for TA and AOH. The widespread occurrence of Alternaria in wheat and its ability to produce mycotoxins suggests the possible occurrence of its toxins in wheat naturally infected with this fungus.     

Optimization of the Method of Detection of Metabolites Produced by the Alternaria Genus: Alternariol, Alternariol Monomethyl Ether, Altenuene, Altertoxin I and Tentoxin

ABSTRACT: A simple method has been developed in this work for the detection of alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), altertoxin I (ATX-I), tenuazonic acid (TA), and tentoxin by means of thin-layer chromatography from cultures of several strains of Alternaria. Strains were incubated in 2% malt extract broth for 7 d at 25 °C. For extraction of metabolites, chloroform was used. The solvent system benzene/methanol/acetic acid (92:6:2) was chosen. TLC plates were observed under ultraviolet light (254/366 nm). Results show that A. alternata IMI 354942 produced AOH, AME, ALT, ATX-I, tentoxin, and TA; A. alternata IMI 354943, AOH, AME, and TA; A. triticina IMI 289962 tentoxin; and A. triticina IMI 289680 AME, ATX-I, and TA.     

Isotope Internal Standard Method for Determination of Four Acrylamide Compounds in Food Contact Paper Products and Food Simulants by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry

A new method was developed for the determination of four acrylamide compounds (acrylamide, methacrylamide, N-methylol acrylamide, N-(Methoxymethyl)methacrylamide) in food contact paper products, three kinds of water-based food simulants, and dry food simulant (modified polyphenylene oxide, MPPO) by using ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Acetonitrile was used as the extraction solvent for different kinds of samples. The extraction solution of paper products was purified with QuEChERS technology. Four analytes were separated by gradient elution in a UPLC HSS T3 column (100 mm?×?2.1 mm, 1.8 μm) with methanol and 0.1 % formic acid water as mobile phases, and then detected in electrospray ionization mode of MS/MS with multiple reaction monitoring (MRM). Under the optimal conditions, the calibration curves for four analytes were linear within the range of 1.0–200 μg/L and the correlation coefficients were higher than 0.998. The quantitation limits of the method (S/N?=?10) of four analytes were in the range of 0.3–20 μg/kg. The mean recoveries for five sample matrixes at three spiked concentration levels of 0.3–200 μg/kg were in the range of 81–108 % with the relative standard deviations (RSDs, n?=?6) values ranging from 2.5 to 7.1 %. The developed method is accurate, simple and rapid, which can be applied to the determination of acrylamide compounds in food contact paper products and food simulants.     

番茄交链孢菌病斑及其外延组织中交链孢毒素的分布

目的 检测不同大小的交链孢菌病斑及其外延组织中交链孢毒素残留量, 明确交链孢毒素在番茄中的迁移规律。方法 样品经80%乙腈溶液提取后, 通过自制固相萃取柱排除杂质干扰, 流出液经氮吹至近干后, 采用超高效液相色谱-串联质谱仪(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定交链孢毒素残留量。结果 不同大小病斑组织中均检测到高浓度的4种交链孢毒素残留, 包括交链孢酚(alternariol, AOH), 交链孢酚单甲醚(alternariol monomethyl ether, AME), 细交链格孢酮酸(tenuazonic acid, TeA)和交链孢烯(altenuene, ALT); 外延组织中仅在病斑周围1 cm处检测到TeA, 含量为病斑组织的1/10左右。结论 番茄交链孢毒素能向病斑外延组织扩散, 但扩散情况与病斑大小无直接联系, 病斑周围2 cm处虽然用超高效液相色谱-串联质谱仪检测不到交链孢毒素, 但仍存在安全风险, 因此, 建议食用时或生产中将病斑及其外延2 cm范围内组织均剔除。     

Determination of Trace Elements in Camellia Oil by Vortex-Assisted Extraction Followed by Inductively Coupled Plasma Mass Spectrometry

A simple vortex-assisted liquid–liquid extraction protocol followed by ICP-MS has been developed for the determination of nine elements (Cr, Mn, Fe, Ni, Cu, As, Zn, Cd, and Pb) in camellia oil samples. The key parameters affecting the extraction efficiency (extraction solvent characteristics, extraction time, and solvent/oil ratio) were carefully examined and optimized. Optimum results were obtained when 5 g of oil sample was used followed by vortex-assisted extraction for 20 min with 10 mL of 10 % HNO₃ (v/v). Detection limits ranging from 0.03 to 1 μg L^?1 and relative standard deviation lower than 6 % were obtained. The accuracy of the method was assessed by spiking experiments and comparison of the results from the extraction procedure with those obtained from microwave-assisted digestion of the samples. The recoveries were in the range of 84.3~102.3 %. No statistical differences, based on t test at a confidence level of 95 %, were detected. The proposed method was found to be simple, fast, and accurate when applied to camellia seed oil samples and has great potential in quantitatively detecting elements in various oils.