Analysis Of Phthalic Acid Esters Research Articles

Octadecyl-fibrous mesoporous silica nanospheres coated 96-blade thin-film microextraction for high-throughput analysis of phthalic acid esters in food and migration from food packages

A high-throughput sample pre-treatment method combined with high-performance liquid chromatography (HPLC) was developed to analyze phthalates (PAEs) in food and food contact package samples. Thin film microextraction (TFME) in 96-blade format was used to pre-treat 96 samples simultaneously. Octadecyl groups functionalized fibrous mesoporous silica nanospheres, namely C18-FMSNs, were synthesized and used as TFME coating material. The coating was fabricated by spraying a slurry of C18-FMSNs and polyacrylontrile (PAN) mixture with a commercial portable spraypen. The prepared C18-FMSNs/PAN coatings exhibited good reproducibility, repeatability and reusability. The optimized TFME conditions for PAEs consisted of extraction at pH 4.0 for 50 min, and desorption by methanol/acetonitrile (25/75, V/V) for 40 min. The pretreatment time for each sample was approximately 1.3 min. This TFME-HPLC method showed good linearity for eight PAEs within the concentration range of 0.5–1000 ng mL−1, with the coefficients higher than 0.9972. The limits of detection and quantification were 0.096–0.26 ng mL−1 and 0.32–0.86 ng mL−1, respectively. The intra-day and inter-day RSD % were below 6.6 % and 8.4 %, respectively, indicating good precision. The PAEs analysis in real samples showed that dibutyl phthalate (DBP) of 2.3 ± 0.3 ng mL−1 and di-(2-ethylhexyl) phthalate (DEHP) of 5.5 ± 0.8 ng mL−1 in boxed milk, dimethyl phthalate (DMP) of 12.6 ± 0.8 ng mL−1, DBP of 3.2 ± 0.4 ng mL−1and DEHP of 14.3 ± 0.7 ng mL−1 in the simulated water migration of plastic box, as well as DMP of 19.0 ± 0.6 ng mL−1, DBP of 25.6 ± 0.9 ng mL−1 and DEHP of 49.5 ± 2.8 ng mL−1 in the simulated ethanol migration of plastic box were determined, respectively. In addition, the detection of PAEs in all the real samples showed good recovery ranging from 85.6 to 110 % and lower RSDs % (<7.2 %).

Determination and Traceability Analysis of Phthalic Acid Esters in Garlic (Allium stivum L.) from Jiangsu Province, China

Phthalic acid esters (PAEs) are ubiquitous environmental pollutants and are recognized as a threat to the environment and agricultural product safety across the world. In order to investigate the level of PAEs in garlic, soils, and agricultural films from Pizhou City, Jiangsu province, China, 11 garlic samples, 106 soil samples, and 4 agricultural film samples were collected and analyzed using GC-MS. In addition, the uptake and transport characteristics of six PAEs compounds classified as priority pollutants by the United States Environmental Protection Agency (EPA) in the garlic cultivar Daqingke were investigated under hydroponic conditions. The results indicated that dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were the dominant PAEs species in garlic cloves of the different garlic varieties from Pizhou City. The average contents of DBP and DEHP in garlic cloves were 0.611 mg·kg-1 and 0.167 mg·kg-1, respectively, which were significantly higher than those of the commercial varieties of garlic. The concentrations of DBP and DEHP differed in three tissues of garlic bulbs, ordered as the skin of garlic bulb>skin of garlic clove>garlic clove. Dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), DBP, and DEHP were the main PAEs species and were detected in all the surface soils collected from Pizhou City. Compared with the soil allowable concentrations of the six PAEs in the United States, the DMP and DBP concentrations in approximately 100% and 63.2% of soil samples exceeded the recommended allowable concentrations set by the EPA. However, the levels of DEP, DIBP, and DEHP in the soils were below the maximum allowable concentrations set by the EPA. Nevertheless, the average content of DEHP in soils was 486 μg·kg-1 and was found to be much higher than that in the other four PAEs. Six PAEs, including DMP, DEP, DIBP, DBP, butyl benzyl phthalate (BBP), and DEHP, were detected in all the agricultural film samples. Among them, the contents of DBP and DEHP in the agricultural films were the highest, accounting for 53.7%-63.2% of the total PAEs. The amount of PAEs present in the residual film was significantly lower than that in the new film, and all six PAEs were detected in garlic or soil samples, suggesting that agricultural film can be an important source of PAEs in garlic farming soils and garlic. Furthermore, the garlic plants absorbed DMP and DEP efficiently from the substrate and showed higher translocation factors (TFs) for DMP and DEP than those for DBP, BBP, DEHP, and di-n-octyl phthalate (DnOP), resulting in a higher accumulation of DMP and DEP in the over-ground parts of garlic. In contrast, DBP and BBP in roots of garlic displayed higher bioconcentration factors (57.4 and 81.5, respectively) compared to those of the other four PAEs, whereas the TFs of DBP and BBP were lower; this may have contributed to the high accumulation of DBP in garlic bulbs. The BCFs and TFs of DEHP and DnOP in garlic were relatively lower, but the DEHP had been detected in all garlic cloves, which may be a result of the higher DEHP contents in soils.

Matrix compatibility of typical sol-gel solid-phase microextraction coatings in undiluted plasma and whole blood for the analysis of phthalic acid esters.

Sol–gel materials have been widely used for solid-phase microextraction (SPME) coatings due to their outstanding performance; in contrast, sol–gel SPME coatings have seldom been used for in vivo sampling. The main reason is that their matrix compatibility is unclear. In order to promote the application of this type of coating and accelerate the development of in vivo SPME, in this study, the matrix compatibility of several typical sol–gel coatings was assessed in plasma and whole blood using phthalic acid esters as analytes. The service life of five kinds of sol–gel coatings was among 20–35 times in undiluted plasma, while it was 27 times for a homemade commercial polydimethylsiloxane coating, which indicates good matrix compatibility of sol–gel coatings in untreated plasma. The sol–gel hydroxy-terminated silicone oil/methacrylic acid fiber achieved the highest extraction ability among all of the fibers, and it was tested in pig whole blood. It could be continuously used for at least 22 times, demonstrating good potential for in vivo sampling. Subsequently, a direct-immersion SPME/gas chromatography-flame ionization detection method was established for the determination of 5 phthalic acid esters in blood. Compared with other methods reported in the literature, this method is rapid, simple, sensitive, and accurate, and does not need expensive instruments or tedious procedures. A simulation system of animal blood circulation was constructed to verify the practicability of sol–gel SPME coatings in animal vein sampling. The result illustrated the feasibility of that coating for in vivo blood sampling, but a more accurate quantification calibration approach needs to be explored.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s00216-022-03890-2.

Analysis of phthalic acid esters in agricultural soils.

The aim of the study was monitoring of phthalic acid esters in agricultural soils of the Czech Republic over the period of 6years, namely dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP). Monitoring took place in twelve regions of the Czech Republic. Soil samples were taken evenly from the top and bottom soil horizons using a zig-zag pattern. Soil samples were taken from arable land, permanent grassland, and hop field. Lyophilisation of the samples was done by ultrasound-assisted extraction using a mixture acetone-hexane (1:1). Phthalic acid esters were analysed using high-performance liquid chromatography with UV detection. Subsequently, the results were statistically compared by analysing the principal components (PCA) to determine the effect of individual factors on the content of phthalic acid esters in agricultural soil. Factors such as precipitation, distance from a pollution source, amount of pesticides, and amount of artificial and organic fertilizers were taken into account. If we compare the concentrations established in this study with the limits set out in the Methodological Instruction of the Ministry of the Environment of the Czech Republic based on RSLs (Regional Screening Levels) issued by the USEPA (United States Environmental Protection Agency), none of these values were exceeded.

Analysis of phthalic acid esters in sea water and sea sand using polymer-coated magnetic nanoparticles as extraction sorbent

In this work, poly(dopamine)-coated magnetic nanoparticles (Fe3O4@pDA) have been used as sorbents for the magnetic dispersive solid-phase extraction (m-dSPE) of a group of 10 phthalic acid esters (dipropyl phthalate, DPP, dibutyl phthalate, DBP, dicyclohexyl phthalate, DCHP, bis(2-ethylhexyl)phthalate, DEHP, di-n-octyl phthalate, DNOP, diisodecyl phthalate, DIDP, butylbenzyl phthalate, BBP, diisononyl phthalate, DINP, diisopentyl phthalate, DIPP, di-n-pentyl phthalate, DNPP) and one adipate (di(2-ethylhexyl) adipate, DEHA) from sea water and sea sand extracts employing DBP-d4 and DHP-d4 as internal standards. After m-dSPE, analysis was carried out by gas chromatography mass spectrometry. Mean recovery values (which were determined at three concentration levels) ranged between 70 and 120%, with relative standard deviation values ≤ 20%, for nearly all analytes in both matrices. Matrix-matched calibration curves revealed the presence of matrix effects for certain PAEs, specially for sea sand, though linearity was assayed with determination coefficients (R2) above 0.991 for all target analytes. The limits of quantification of the method were in the range 1.8–319 ng/L for sea water and 0.020–4.0 ng/g for sea sand. Several samples of each type collected at different sites of the coast of Tenerife were also analysed. Only DEHA, DNOP and DIPP were detected in some of the sea sand samples at concentrations ≤ 44 ng/g.

Chemical bonding of oxygenated carbon nitride nanosheets onto stainless steel fiber for solid-phase microextraction of phthalic acid esters

In this work, oxygenated carbon nitride nanosheets (OCNNSs) were first introduced to the field of analytic chemistry for solid-phase microextraction (SPME). The rich hydroxyl and carboxyl contents of OCNNSs provided abundant adsorption sites. The coated stainless steel fibers, synthesized by the layer-by-layer chemical bonding method, had good chemical stability (in organic solvents), long life (durability ≥ 150 cycles), and good reproducibility (RSDs ≤ 9.2%). This novel OCNNSs-coated fiber was used for SPME with gas chromatography-mass spectrometry (GC-MS) for the analysis of phthalic acid esters (PAEs) in three types of food products (seafood, samshu, and instant noodles). Under optimal conditions, the limits of detection (LODs) for the PAEs ranged from 0.1 to 10.0 pg mL−1, and recovery was in the range of 80.0–118.1%. These novel coated SPME fibers displayed excellent separation and enrichment properties, which suggest a pretreatment application for analysis of PAEs.

Determination of phthalate acid esters plasticizers in polyethylene terephthalate bottles and its correlation with some physicochemical properties

A method for the analysis of phthalic acid esters or phthalates (PAEs) in polyethylene terephthalate (PET) bottles based on the use of microwave-assisted extraction (MAE) and liquid chromatography with UV detection (LC-UV) was developed. The microwave-assisted extraction procedure was optimized by a three factors Box–Behnken response surface design. High PAEs recoveries were obtained by microwave-assisted extraction using 70% of acetonitrile at 140 °C during 30 min.Moreover, some physical properties of PET samples as thickness, and crystallization and melting temperatures were determined by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. Those parameters were correlated, through Pearson correlation coefficient, with the content of PAEs determined in PET containers (dimethyl phthalate (DMP), diethyl phthalate (DEP) and dibutyl phthalate (DBP)) and with the content of PAEs in water obtained from a migration test in PET. The migration procedure was based on a standardized procedure (EU 82/711/EEC and 85/572/EEC directives) stipulated by the European Union (EU). The concentrations of PAEs found in PET bottles were between 1.1 and 14.8 mg kg−1 for DMP, 9.3 and 63.6 mg kg−1 for DBP and DEP was only detected in one of the 10 analyzed samples at a concentration of 3.1 mg kg−1. The analysis of the samples obtained by applying the migration test showed that DBP was found in five of the ten analyzed samples reaching concentrations from 14.5 up to 25.6 μg L−1. DMP was found in five of the ten analyzed samples, with concentrations from 4.1 to 50.6 μg L−1, whereas DEP was not detected in any of the analyzed samples. The results of the Pearson correlation coefficient indicated that there was a significant correlation between the thickness and the total concentration of PAEs in the PET samples (95% confidence interval), as well as the DBP content in PET samples and the concentration of DBP migrated from bottles to the water (90% confidence interval), indicating that the content of PAEs in the samples and the migration rate of these compounds was related to the physical characteristics of PET bottles.

Development of an air-flow-assisted extractive electrospray ionization source for rapid analysis of phthalic acid esters in spirits.

Although traditional analytical techniques like gas chromatography (GC) and GC/mass spectrometry (MS) offer satisfactory sensitivity and good reproducibility for the detection of phthalic acid esters (PAEs) in a variety of matrices, they involve laborious sample pretreatment, are time-consuming, and some are expensive and environmentally unfriendly. Furthermore, there are thousands of spirits on the market; therefore, rapid and high-throughout methods suitable for the consistent detection and quantification of PAEs in spirits are urgently required. A new atmospheric pressure ionization method, named air-flow-assisted extractive electrospray ionization (EESI), has been developed. It is a variant on EESI and possesses the advantages of both EESI and air-flow-assisted ionization for direct analysis of samples without pretreatment. Combined with a quadrupole time-of-flight (QTOF) mass spectrometer, the method was used to directly analyze four PAEs, i.e., dipentyl phthalate, diethyl phthalate, benzyl butyl phthalate and didecyl phthalate, in spirits. The method exhibits excellent sensitivity, stability and convenience. Four different brands of spirits have been successfully analyzed. The total analysis time for one sample was within 1 min, and the limits of detection and limits of quantification of the samples are located in the range 0.011-0.035 and 0.038-0.087 µg g(-1), respectively. Very good linearities, with correlation coefficients of 0.9758-0.9990, are observed for the samples in the range of 0.035 to 10 µg g(-1). The results indicate that the air-flow-assisted EESI combined with tandem mass spectrometry is an effective method for rapid and direct determination of PAEs in spirits without sample pretreatment.

Analysis of Phthalic Acid Esters in Soil and Peanut from Guangdong Province

This study investigated the contents of 5 phthalic acid esters in the soil and peanut from Ningxi and Huazhou farms. 5 PAEs were detected by gas chromatography coupled with mass spectrometry (GC-MS) in soil and peanut. The soil background concentrations of PAEs ranged from 0.438 to 1.624 mg/kg in Ningxi and that range in Huazhou was from 0.468 to 1.235 mg/kg. The results showed that BBP and DEHP were both the major PAEs, and DEHP was the major PAEs of both sites. PAEs in the soil of two sites were contaminated slightly. The PAEs contents in peanut kernels ranged from 2.466 to 8.888 mg/kg and 3.436 to 5.594 mg/kg, respectively. Results show that the order of PAEs concentration of peanut in the both sites was: root &gt; stem &gt; leave &gt; shell.

Determination of phthalate esters in edible oils by use of QuEChERS coupled with ionic-liquid-based dispersive liquid-liquid microextraction before high-performance liquid chromatography.

A selective and low organic-solvent-consuming method of sample preparation combined with high-performance liquid chromatography with diode-array detection is introduced for analysis of phthalic acid esters in edible oils. Sample treatment involves initial liquid-liquid partitioning with acetonitrile, then QuEChERS cleanup by dispersive solid-phase extraction with primary secondary amine as sorbent. Preconcentration of the analytes is performed by ionic-liquid-based dispersive liquid-liquid microextraction, with the cleaned-up extract as disperser solvent and 1-hexyl-3-methylimidazolium hexafluorophosphate as extraction solvent. Under the optimized conditions, correlation coefficients (r) were 0.998-0.999 and standard errors (S y/x ) were 2.67-3.37 × 10(3) for calibration curves in the range 50-1000 ng g(-1). Detection limits, at a signal-to-noise ratio of 3, ranged from 6 to 9 ng g(-1). Intra-day and inter-day repeatability, expressed as relative standard deviation, were in the ranges 1.0-6.9 % and 2.4-9.4 %, respectively. Recovery varied between 84 % and 106 %. The developed method was successfully used for analysis of the analytes in 28 edible oils. The dibutyl phthalate content of four of the 28 samples (14 %) exceeded the specific migration limit established by domestic and international regulations.

A new procedure combining GC-MS with accelerated solvent extraction for the analysis of phthalic acid esters in contaminated soils

An optimized procedure based on gas chromatography-mass spectrometry (GC-MS) combined with accelerated solvent extraction (ASE) is developed for the analysis of six phthalic acid esters (PAEs), which are priority soil pollutants nominated by United States Environmental Protection Agency (USEPA). Quantification of PAEs in soil employs ultrasonic extraction (UE) (USEPA 3550) and ASE (USEPA 3545), followed by clean up procedures involving three different chromatography columns and two combined elution methods. GC-MS conditions under selected ion monitoring (SIM) mode are described and quality assurance and quality control (QA/QC) criteria with high accuracy and sensitivity for target analytes were achieved. Method reliability is assured with the use of an isotopically labeled PAE, di-n-butyl phthalate-d4 (DnBP-D4), as a surrogate, and benzyl benzoate (BB) as an internal standard, and with the analysis of certified reference materials (CRM). QA/QC for the developed procedure was tested in four PAE-spiked soils and one PAE-contaminated soil. The four spiked soils were originated from typical Chinese agricultural fields and the contaminated soil was obtained from an electronic waste dismantling area. Instrument detection limits (IDLs) for the six PAEs ranged 0.10–0.31 μg·L−1 and method detection limits (MDLs) of the four spiked soils varied from a range of 20–70 μg·kg−1 to a range of 90–290 μg·kg−1. Linearity of response between 20 μg·L−1 and 2 mg·L−1 was also established and the correlation coefficients (R) were all>0.998. Spiked soil matrix showed relative recovery rates between 75 and 120% for the six target compounds and about 93% for the surrogate substance. The developed procedure is anticipated to be highly applicable for field surveys of soil PAE pollution in China.

Rapid and nondestructive analysis of phthalic acid esters in toys made of poly(vinyl chloride) by direct analysis in real time single‐quadrupole mass spectrometry

In the European Community, selected phthalic acid esters (PAE) are restricted in their use for the manufacture of toys and childcare articles to a content of 0.1% by weight. As PAE are mainly used as plasticisers for poly(vinyl chloride) (PVC), a rapid screening method for PVC samples with direct analysis in real time ionisation and single-quadrupole mass spectrometry (DART-MS) was developed. Using the ions for the protonated molecules, a limit of detection (LOD) of 0.05% was obtained for benzyl butyl phthalate, bis(2-ethylhexyl) phthalate and diisononyl phthalate, while for dibutyl phthalate, di-n-octyl phthalate and diisodecyl phthalate the LOD was 0.1%. Validation of identification by the presence of ammonium adducts and characteristic fragment ions was possible to a content of >or=1% for all PAE, except for benzyl butyl phthalate (>or=5%). Based on the fragment ions, bis(2-ethylhexyl) phthalate could clearly be distinguished from di-n-octyl phthalate, if the concentrations were >r=5% and >or=1% at measured DART helium temperatures of 130 and 310 degrees C, respectively. The complete analysis of one sample only took about 8 min. At the generally used gas temperature of 130 degrees C, most toy and childcare samples did not sustain damage if their shape fitted into the DART source.

Evaluation of a clean‐up procedure for the determination of phthalic acid esters in sewage sludge

Abstract A method has been developed for the analysis of phthalic acid esters in sewage sludges. Individual steps in the analytical procedure have been evaluated for the six phthalate esters listed as, United States Environmental Protection Agency priority pollutants, that is dimethyl, diethyl, di‐n‐butyl, butyl benzyi, di‐(2‐ethyl hexyl) and di‐n‐octyl phthalates. The main steps involved in the analysis are extraction with dichloromethane/hexane, clean up on silver coated alumina columns, and quantification with ECD Gas Chromatography. The method is applied to digested sewage sludge. Mean recovery for the six phthalates was between 63 and 90% with relative standard deviations of 4 to 15%.