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In this research, a poly (ionic liquid) functionalised silica-coated magnetic nanoparticles were synthesised for the first time and utilised as a novel adsorbent for the simultaneous extraction of six phthalic acid esters from polyethylene terephthalate bottled drinking water samples. The adsorbent was prepared by grafting poly (1-benzyl-3-vinyl-1 H-imidazol-3-ium chloride) onto silica-coated Fe3O4nanoparticles via Cu(0)-mediated reversible-deactivation radical polymerisation method. Various techniques were used to characterise the synthesised nanomaterials. A qualitative analysis was performed using ultra-performance liquid chromatography triple–quadrupole tandem mass spectrometry. Response surface methodology based on central composite design was used to optimise the extraction procedure and the optimised condition for each factor was; pH of3.9, 22 mg of adsorbent, 3.5 min extraction time, 3 min desorption time, 340 µL of elution solvent (methanol).The results of the validation of the method indicated its acceptable accuracy (88.6-100.1%), good linearity (r > 0.995), satisfactory repeatabilities (RSDs ≤ 6% for intra- and inter–day precisions) and high enrichment factors (535–572). The limits of detection and limits of quantification of the proposed method achieved were 1.1-4.6 ngL–1and 3.6-15.3 ngL–1, respectively. In this study, six common PAEs, including dimethyl phthalate, diethyl phthalate, dibutyl phthalate, benzyl butyl phthalate, bis (2-ethylhexyl) phthalate, and di-n–octyl phthalate, were found in PET bottled water within the range of 0.21-0.94 μgL–1, under different storage conditions. Nevertheless, only a negligible risk is caused by the PAEs in PET bottled water for consumers following the recommendations, such as storing at a common place (25°C), in a short period away from the sun. [ABSTRACT FROM AUTHOR]

Di-n-butyl phthalate (DBP) is one of the most extensively used phthalic acid esters (PAEs) and is considered to be an emerging, globally concerning pollutant. The genus Streptomyces holds promise as a degrader of various organic pollutants, but PAE biodegradation mechanisms by Streptomyces species remain unsolved. In this study, a novel PAE-degrading Streptomyces sp. FZ201 isolated from natural habitats efficiently degraded various PAEs. FZ201 had strong resilience against DBP and exhibited immediate degradation, with kinetics adhering to a first-order model. The comprehensive biodegradation of DBP involves de-esterification, β -oxidation, trans-esterification, and aromatic ring cleavage. FZ201 contains numerous catabolic genes that potentially facilitate PAE biodegradation. The DBP metabolic pathway was reconstructed by genome annotation and intermediate identification. Streptomyces species have an open pangenome with substantial genome expansion events during the evolutionary process, enabling extensive genetic diversity and highly plastic genomes within the Streptomyces genus. FZ201 had a diverse array of highly expressed genes associated with the degradation of PAEs, potentially contributing significantly to its adaptive advantage and efficiency of PAE degradation. Thus, FZ201 is a promising candidate for remediating highly PAE-contaminated environments. These findings enhance our preliminary understanding of the molecular mechanisms employed by Streptomyces for the removal of PAEs. [Display omitted] • The novel PAE degrader strain FZ201 was isolated from the root surface of wild rice. • Streptomyces sp. FZ201 harbours redundant genes involved in the biodegradation of PAEs. • The integration of enzymes suggested a composite catabolic network in FZ201. • Streptomyces species harbour various PHX genes that are responsible for PAE degradation. • Pangenome analysis revealed a highly plastic genome within the Streptomyces genus. [ABSTRACT FROM AUTHOR]

This study examined phthalate esters (PAEs) in pediatric enteral formula (PEF) samples in Turkey and their potential impact on consumers. Among the various types and forms of PEF sample, Type 5 had the highest total concentration of PAEs (71.52 µg/kg) for polimeric (PC) formulas, followed by Type 1 (60.33 µg/kg) for oligomeric (OC) formulas, and Type 1 (55.05 µg/kg) for monomeric (MC) formulas. However, no statistically significant differences were observed in the concentrations of PAEs among the different types of PEF samples (p > 0.05). The ranking of PEF samples based on their total PAEs levels was as follows: MC (54.94 µg/kg)> OC (54.05 µg/kg)> PC (53.32 µg/kg). DEHP, DINP, DNOP and DEP were the most abundant PAEs. Health risk assessments the carcinogenic risk associated with DEHP was determined to be at an acceptable cancer risk level (Grade: B) for all age and gender groups. Additionally, the dietary intake levels of each PAEs, including DEHP, DINP, DEP, and DBP, were found to be below the values established by the European Food Safety Authority for tolerable daily intake. Continuous monitoring and regulation are crucial to ensure PEF safety and reduce PAEs exposure risks. • Comprehensive analysis of PAEs in enteral nutrition formulas from Turkey. • Uniformity in PAE levels found in 25 sampled formulas. • Safe PAE exposures: EFSA TDIs not exceeded in the Turkish market. • Acceptable carcinogenic risk: DEHP in enteral nutrition formulas. [ABSTRACT FROM AUTHOR]

A new hybrid solid-phase microextraction coating, [Ba(5,5ʹ-dcbipy)(µ-H2O)2 (H2O)2]n and polypyrrole, has been prepared using an electrochemical method. The fibre was well characterised and showed superior properties. The fibre showed excellent thermal stability, adherently and chemical stability which were suitable for extracting analytes from harsh media and desorbing them in a high thermal inlet of a GC. Four phthalate esters were extracted with this fibre and then analysed via GC-flame ionisation detector. Salt concentration, temperature and time of extraction were optimised. The detection limits and linear ranges were 0.077–0.25 μg L−1 and 0.125–500 to 0.25–125 μg L−1, respectively. The intra-day and inter-day relative standard deviations were found to be 6.9–9.4 and 2.9–23.4%, respectively. The results then were compared with other works. Phthalates in two different aqueous samples of food products were successfully analysed with the proposed method. [ABSTRACT FROM AUTHOR]

Polythionine was prepared by a simple electrochemical method and used as solid-phase microextraction coating for headspace extraction and analysis of four phthalate esters (dioctyl phthalate, benzyl butyl phthalate, di-n-butyl phthalate, and di-iso-butyl phthalate) by gas chromatographic-flame ionization detector. The thionine polymerization was performed at pH of 9 on a Pt wire. Made ready coating displayed a good thermal stability (up to 280 °C). The effects of three extraction parameters, containing salt effect, temperature and extraction time, on the extraction efficiencies of phthalate esters were evaluated. Under the optimized conditions, limits of detection were among 0.34–1.67 µg L−1. The inter-day and intra-day deviations of relative standard, attained at 50 µg L−1, were 7.64–10.62% and 10.14–12.84%, respectively. The method capability for analysis of the phthalates in real samples of cheese water and wastewater was evaluated and relative recoveries were between 82.63 and 119.50%. [ABSTRACT FROM AUTHOR]

Summary: The complete degradation of the xenobiotic and environmentally harmful phthalate esters is initiated by hydrolysis to alcohols and o‐phthalate (phthalate) by esterases. While further catabolism of phthalate has been studied in aerobic and denitrifying microorganisms, the degradation in obligately anaerobic bacteria has remained obscure. Here, we demonstrate a previously overseen growth of the δ‐proteobacterium Desulfosarcina cetonica with phthalate/sulphate as only carbon and energy sources. Differential proteome and CoA ester pool analyses together with in vitro enzyme assays identified the genes, enzymes and metabolites involved in phthalate uptake and degradation in D. cetonica. Phthalate is initially activated to the short‐lived phthaloyl‐CoA by an ATP‐dependent phthalate CoA ligase (PCL) followed by decarboxylation to the central intermediate benzoyl‐CoA by an UbiD‐like phthaloyl‐CoA decarboxylase (PCD) containing a prenylated flavin cofactor. Genome/metagenome analyses predicted phthalate degradation capacity also in the sulphate‐reducing Desulfobacula toluolica, strain NaphS2, and other δ‐proteobacteria. Our results suggest that phthalate degradation proceeds in all anaerobic bacteria via the labile phthaloyl‐CoA that is captured and decarboxylated by highly abundant PCDs. In contrast, two alternative strategies have been established for the formation of phthaloyl‐CoA, the possibly most unstable CoA ester in biology. [ABSTRACT FROM AUTHOR]

The international analytical standard IEC 62321–3–3 describes a method for the screening analysis of phthalate esters, polybrominated diphenyl ethers (PBDEs), and polybrominated biphenyls (PBBs) in polymers by pyrolyzer/thermal desorption-gas chromatography-mass spectrometry (Py/TD-GC/MS). The IEC 62321–3–3 method uses a database of relative response factors (RRFs) (calculated by dividing the response factor (RF) for a target compound by the RF value for a substitute compound (SC) selected from among all target compounds) to quantitate each targeted analyte. A drawback of this method is that a separate RRF database must be created from expensive standard solutions that contain each targeted compound for each instrument, which is a labor-intensive task. In this study, we have developed a "ready-to-use" RRF database that can be used on multiple different instruments. This method eliminates the need to create an RRF database for each instrument and greatly simplifies the screening workflow described in the IEC 62321–3–3 standard. Because it only requires a mixed n-alkane solution and polymer reference materials, which are generally easy to procure and easy to use, the method is highly convenient and suitable for general-purpose use. Assigning tetra-BDE, penta-BDE, deca-BDE, or deca-BB as the SC for each PBDE and PBB analyte allowed the variance in RRFs between instruments to be reduced to a degree suitable for screening analysis. When this method was applied, recovery rates of individual PBDEs and PBBs remained within the range of 74–130 % over an extended period of 54 months. Simultaneous analysis of phthalate esters, PBDEs, and PBBs in various polymer reference materials was also performed with the optimized method on four different instruments and recovery rates of each targeted compound were evaluated. The recovery rates for each phthalate ester, total PBDEs, and total PBBs were within the range of around 100 ± 30 % for all tested samples. [Display omitted] • Optimized RRF database for Py/TD-GC/MS to screen phthalates, PBDEs, and PBBs without needing standard solutions for the compounds. • Tetra, penta, deca-BDE, or deca-BB are assigned as substitute compounds for individual PBDEs and PBBs. • The database maintains suitable quantitative accuracy for 54 months. • Individual compound recovery rates within around 100 ± 30 % for various samples on four different instruments. [ABSTRACT FROM AUTHOR]

• A simple and "direct" method for phthalate analysis in vegetable oils is proposed. • Sample preparation involved only dilution with a suitable solvent. • Twenty-seven vegetable oils were analyzed by using GC × GC with triple quadrupole MS. • Nine vegetable oils were found to be contaminated by DPP, DEHP, DiNP, and DiDP. Phthalic acid esters (PAEs), known as phthalates, have a variety of industrial applications, mainly related to their ability to increase plastic softness, flexibility, and durability. With regard to toxicological aspects, several studies suggest that phthalates would act as endocrine-disrupting chemicals, and they have been correlated to several forms of cancer. Since the analysis of PAEs in food is challenging, the aim of this study was the development of a simple and direct method, with no sample preparation (only dilution with solvent), for the analysis of targeted phthalates in vegetable oils, by using cryogenic-modulation comprehensive two-dimensional gas chromatography combined with triple quadrupole mass spectrometry. The method was characterized by good repeatability values, limit of quantification values ranging between 0.06 and 2.10 mg/kg, accuracy values ranging from −9.2 to 10.4%, and a matrix effect ranging from −4 to 78%. The developed technique was used for the analysis of 27 vegetable oils. [ABSTRACT FROM AUTHOR]

Phthalate Esters (PAEs) are a group of chemicals widely used in plastic products, and they are also known as endocrine disruptors that can adversely affect the hormonal balance in humans. Since many food-contacting items, such as lunch boxes, fresh keeping film, disposable cups, are made of plastic, the PAEs can easily enter the human body through the polluted foods or drinks. Traditional analytical techniques involve laborious sample pretreatment and low-throughput analysis, so it is necessary to develop techniques that can rapidly and quantitatively detect these compounds. In this article, a miniaturized ion trap mass spectrometer (ITMS) was established firstly, then, an in-situ thermal desorption atmospheric pressure photoionization (in-situ TD-APPI) was designed, and the dopant was explored using for improving the sensitivity and as internal standard (IS) simultaneously in the analytical process. The in-situ TD-APPI presents good performance: (1) More than 20 times improvement in sensitivity compared with Nano-ESI for PAEs; (2) 12 kinds of phthalates were quantified with using acetone as the IS, and the LODs and LOQs ranges were found to be 0.02–1 μg/mL and 0.02–100 μg/mL, respectively. The technique was also applied to the quantification of mixed solutions, and the results were validated by LC/MS. Finally, six categories of food-contacting items containing PAEs were analyzed with superficial content (ng/cm2) ranging from 0 to 6.20 ng/cm2. These results demonstrate the potential of rapid quantification of analysis of PAEs in practical plastic food-contacting items by in-situ TD-APPI. • More than 20 times improvement in sensitivity was achieved compared with Nano-ESI for PAEs. • 12 kinds of phthalates were quantified, and the LODs and LOQs ranges were found to be 0.02–1 μg/mL and 0.02–100 μg/mL, respectively. • Within 3 s, this technique was applied to quantitatively analyze a mixed solution, and the results were validated by LC/MS. • Six categories of food-contacting items including tinfoil, lunch box, fresh keeping film, disposable cups, dinner plate and plastic spoon were analyzed. [ABSTRACT FROM AUTHOR]