Simultaneous determination of six phthalate esters in bottled milks using ultrasound-assisted dispersive liquid–liquid microextraction coupled with gas chromatography

Analysis and contamination levels of ten phthalic acid esters (PAEs) in Chinese commercial bubble tea: a comparison with commercial milk

Phthalic acid ester (PAE) contamination in popular drink bubble tea has been hardly studied in the world. In this work, a liquid-liquid extraction following solid phase extraction (LLE-SPE)-UPLC-MS/MS method was first established for trace determination of ten PAEs in bubble tea. The developed method was validated with respect to linearity (R2 > 0.992), low limit of detections (LODs, 0.49-3.16 µg/L), and satisfactory recoveries (61.8-127.6%) with a low relative standard derivations (RSDs, 1.1-16.4%), which was also validated for commercial milk. Six out of ten PAEs, i.e., diethylhexyl phthalate (DEHP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), diethyl phthalate (DEP), dihexyl phthalate (DHP), and diphenyl phthalate (DPP) were detected in Chinese bubble tea with concentrations ranging from not detection (ND) to 53.43 µg/L, while DEHP, DBP, DIBP, DEP, and dimethyl phthalate (DMP) were detected in commercial milk with concentrations ranging from ND to 110.58 µg/L. The respective average concentrations of DEHP in Chinese bubble tea and commercial milk were 19.40 and 23.46 µg/L, which were over two times that in drinking water quality standards of several countries including Israel, Korea, Oman, and Singapore (i.e., 8 µg/L). Calculated with human estimated daily intake (EDI), the average EDIs of five out of seven PAEs in bubble tea were higher than those in commercial milk. For example, the calculated EDI of DIBP in bubble tea was 5 times that in commercial milk, while their respective corresponding EDIs of DBP and DEHP were over 2.4 and 1.6 times. Based on estrogen equivalence (EEQ) with the unit of ng E2/L, the average EEQs of the ten PAEs in Chinese bubble tea and commercial milk were 14.26 and 17.06 ng E2/L, which were 52.8 and 62.3 times the observed effect concentration that could cause egg mortality of zebrafish. It is evident that the potential estrogenic effect of PAEs in bubble tea and commercial milk cannot be negligible. Given the fact that PAE contamination in bubble tea has been hardly investigated, such study is urgently to be performed in a global view.

Multi-Residue Analysis of Chemical Additives in Edible Vegetable Oils Using QuEChERS Extraction Method Followed by Supercritical Fluid Chromatography

Since the quality and safety of food highly depend on its preservation and protection, the use of food packaging materials increases the risk of chemical contamination of the packaged food by migration. Herein, we focused on antioxidants, photoinitiators, UV absorbers and plasticizers which are extensive additives used in food packaging materials. In the present study, a rapid, simple, green and reliable method was developed and validated for the determination of twelve chemical additives in edible vegetable oils using SFC together with a modified QuEChERS procedure. Under the optimum conditions, twelve additives were separated within 10 min, and the consumption of the organic solvent was significantly reduced, which improved the environmentally friendliness. The performance of the developed method was evaluated. Good linearity (r > 0.999) was obtained in the range of 0.20−20.0 µg/mL and 0.50−20.0 µg/mL, respectively. The limits of detection and limits of quantification of the twelve additives in vegetable oils were 0.05−0.15 µg/mL and 0.15−0.50 µg/mL, respectively. Recoveries of all the chemical additives for the spiked samples were between 60.9% and 106.4%, with relative standard deviations (RSD) lower than 9.9%. The results demonstrated that the proposed method was efficient, reliable and robust for the routine analysis of additives in edible vegetable oils and can be an alternative to the multi-residue analysis of chemical additives for other packaged foods.

Phthalates in the diet of Mexican children of school age. Risk analysis

Phthalates are widely used as plasticizers, additives, or solvents. Its extensive use has generated environmental and food contamination, which implies continuous population exposure. The aim of this work was to determine the probability of health risk of Mexican children exposed to phthalates through the consumption of contaminated food. A survey was applied to 384 Mexican school-age children (between 6 and 12 years old), to find out the type of food they eat most frequently, based on this, a research was made to know the concentration of phthalates contained in these foods. The daily intake had been calculated with the concentration of phthalates reported in food, obtaining: DEHP (19.50 μg/kg body weight/day), DnBP (5.52 μg/kg body weight/day) y for DEP (1.12 μg/kg body weight/day). The hazard index (HI) for DEP y DEHP was 0.49 to 42.5 for internal organs damage reported. HI for reproductive health damage due to exposure to DnBT and DEHP was of 0.04 to 5.58, so that there is a high probability that children's health is at risk. Therefore, it is necessary to a quantitative analysis of phthalates in food consumed in Latin American countries and establish the TDI of phthalates especially, to DEHP, which was obtained the higher HI.

Plasticisers and preservatives in commercial milk products: A comprehensive study on packages used in the Spanish market

A comprehensive study on packaging used in commercially available milk products from Spanish markets has been presented. Concentrations of four phthalates, seven parabens and BPA were determined in forty-two milk products. Eleven brands and five types of packaging (metallic aluminium bag, carton, high-density polyethylene, metal pail and polyethylene terephthalate) were included in the study. BPA showed the lowest concentrations (8.3 pg/g f.w.), far below those of phthalates (6431 pg/g f.w.) and parabens (6234 pg/g f.w.). Metallic aluminium bags were the least migrating packaging (considering plasticisers and monomers) followed by HDPE bottles, in the case of phthalates. Parabens showed their highest concentrations for fresh-milk samples. Levels found were far below the specific migration limits established by the EU and the cumulative hazard index was lower than 1, indicating that adverse health effects were not expected. In general, the results found in Spanish samples were lower than those reported in other countries.

A comprehensive analysis of metabolomics and transcriptomics reveals new biomarkers and mechanistic insights on DEHP exposures in MCF-7 cells

Di-(2-ethylhexyl) phthalate (DEHP) is one of the most important environmental pollutants and affects multiple pathways upon human exposure. DEHP could induce MCF-7 cell proliferation at a very low dose; however, the possible linkage between DEHP and the cell proliferation effect is still unclear. Here, we carried out a comprehensive metabolome and transcriptome analysis to depict the possible molecular mechanisms of the effect of DEHP exposure on MCF-7 proliferation. In this paper, MCF-7 cells treated with DEHP at a dose of 1 μM for 48 h were selected for metabolome and transcriptome analysis. Untargeted and targeted metabolomics identified 8 differential metabolites, including amino acids, purine, pyrimidine and nucleotides. The metabolite changes were associated with 9 metabolic pathways. Disorders in riboflavin, histidine, beta-alanine metabolism, and nitrogen metabolism caused by DEHP exposure are important concerns for MCF-7 proliferation. Moreover, a transcriptomics study of the MCF-7 cells found a total of 500 differentially expressed genes (DEGs). KEGG enrichment analyses showed that pathways in cancer had stronger responses. The results of integrated analysis of the interactions between the DEGs and metabolites revealed significant changes in the purine metabolism pathway, which will shed light on the mechanism of MCF-7 cell proliferation after DEHP exposure. Overall, this study depicts the possible contribution of DEHP exposure to MCF-7 cell proliferation and highlights the power of omics platforms to deepen the mechanistic understanding of toxicity caused by endocrine disrupting chemicals.

Recent Trends in the Analysis of Chemical Contaminants in Beverages

Chemical contaminants should not be present in beverages for human consumption, but could eventually be ingested by consumers as they may appear naturally from the environment or be produced by anthropogenic sources. These contaminants could belong to many different chemical sources, including heavy metals, amines, bisphenols, phthalates, pesticides, perfluorinated compounds, inks, ethyl carbamate, and others. It is well known that these hazardous chemicals in beverages can represent a severe threat by the potential risk of generating diseases to humans if no strict quality control is applied during beverages processing. This review compiles the most updated knowledge of the presence of potential contaminants in various types of beverages (both alcoholic and non-alcoholic), as well as in their containers, to prevent undesired migration. Special attention is given to the extraction and pre-concentration techniques applied to these samples, as well as to the analytical techniques necessary for the determination of chemicals with a potential contaminant effect. Finally, an overview of the current legislation is carried out, as well as future trends of research in this field.

Easy and Inexpensive Method for Multiclass Analysis of 41 Food Contact Related Contaminants in Fatty Food by Liquid Chromatography-Tandem Mass Spectrometry

Food contact materials (FCMs) may release their chemical components into food and thus raise safety concerns. This paper attempted to study the presence of four major groups of FCM-related endocrine disruptors in fatty food: dialkyl phthalates, bisphenols, printing ink photoinitiators, and polyfluoroalkyl substances. All 41 target compounds were analyzed simultaneously by means of liquid chromatography coupled to tandem mass spectrometry. The sample preparation was significantly streamlined to reduce analysis costs by employing acetonitrile extraction, extract modification by water, and refrigeration at 5 °C. The new method was validated and applied to 60 real samples, including edible oils, butter, and chocolate, where 16 target compounds were measured at levels ≤13000 ng/g. The study also described the blank level increase and sensitivity loss caused by impurities present in the HPLC methanol solvent.

Facile magnetization of covalent organic framework for solid-phase extraction of 15 phthalate esters in beverage samples

Phthalate esters (PAEs), a category of widely used plasticizers, are tend to migrate from plastic packaging to drinks. In this paper, we develop a simple and rapid coprecipitation method for synthesis of a magnetic covalent organic framework (COF) adsorbent. The fabricated COF-(TpBD)/Fe₃O₄ was applied to magnetic solid phase extraction (MSPE) of 15 phthalate esters (PAEs) for subsequent GC-MS/MS determination in beverage samples. The as-synthesized magnetic adsorbent exhibited great potential in PAEs analysis with a limit of detection of 15 PAEs ranged from 0.005 to 2.748 μg L^-1 (S/N = 3). The intra-day and inter-day relative standard deviations (RSD) value of the PAEs were less than 8.8% and 9.9%, respectively. The adsorbent can be reused after washing with methanol. The developed method was successfully applied for the determination of trace PAEs in eight beverages with recoveries ranging from 79.3% to 121.8% and RSDs were less than 11.9%. This work provides a simple magnetization process, which facilitates the application of COFs for enrichment and separation of PAEs in beverages with different matrices.

Determination of phthalate esters in seawater of Chabahar Bay using dispersive liquid-liquid microextraction coupled with GC-FID

Phthalate esters (PEs), a group of environmental pollutants which are possibly carcinogenic to humans, have been detected in seawater. Seven PEs in seawater were quantitatively determined by using gas-chromatography flame ionizing detection after executing dispersive liquid-liquid microextraction. The suggested method is optimized for microextraction and determination of PEs in artificial sea water. Factors affecting the microextraction procedure such as the type and volume of extracting and dispersive solvents (carbon tetrachloride, 20 μL; methanol, 0.5 mL), extraction time and pH (7) were investigated. Under optimum conditions, the limit of detection of the analytes were obtained between 0.04 and 4.52 μg·L^-1, and linearity and linear range were of 0.999 ≥ R² ≥ 0.994 and 10-560 μg·L^-1 respectively. Enrichment factors were found in the range of 761-827 fold, while the relative standard deviations of the analytes were between 0.17 and 7.5% (n = 6) for real sea water samples. Using this method, total PEs content of seawater from several locations in Chabahar Bay (the southeast part of Iran) was estimated 2.33-90.45 μg·L^-1.

Critical evaluation of several techniques for the analysis of phthalates and terephthalates: Application to liquids used in electronic cigarettes

This study describes several original methods that were developed with the goal of measuring phthalates and terephthalates. These methods include gas chromatography/mass spectrometry (GC/MS), GC/MS/MS, liquid chromatography with UV detection (LC/UV), LC/MS, and LC/MS/MS. The study compares the advantages and disadvantages of these methods and their applicability to measuring phthalates and terephthalates in the liquids used in electronic cigarettes (e-liquids). The analytes evaluated include eight phthalates and two terephthalates. The phthalates were diethyl, dibutyl, benzyl butyl, diphenyl, bis(2-ethylhexyl), di-n-octyl, diisononyl and diisodecyl. The terephthalates were dimethyl and bis(2-ethylhexyl). Intentionally, no cleanup or concentration step were used in the methods. The methods used two chromatographic standards, dimethyl phthalate-3,4,5,6-d₄, and di-(2-ethylhexyl) phthalate-3,4,5,6-d₄. All techniques were validated for selectivity/specificity, precision, sensitivity (evaluation of LOD and LOQ), as well as for repeatability and matrix interference. The GC methods were not adequate for the analysis of diphenyl, diisononyl, and diisodecyl phthalates which were not volatile enough to be seen in the conditions used for the GC separation. Also, alcohols should not be used as solvents for the injection of the sample in the GC system to avoid transesterification in the hot injection port. The single quadrupole MS detection in GC offers sensitivities around 1 μg/mL in the e-liquid and was not sensitive enough for the analysis of trace phthalates and terephthalates. Compared to all evaluated methods, the MS/MS detection in GC offered the best sensitivity (below 10 ng/mL in the e-liquid). The LC is adequate for the separation of all the evaluated analytes. However, the UV detection in LC does not offer good sensitivity compared to all the other techniques. The MS detection in LC provides poor sensitivity for terephthalates, but better than the UV for the rest of the analytes. The MS/MS detection for LC offers slightly better sensitivity than the MS detection, but both LC/MS and LC/MS/MS were only able to measure levels above about 100 ng/mL of analytes in the e-liquid. A group of 39 e-liquids were analyzed by three of the evaluated procedures. Benzyl butyl phthalate, bis(2-ethylhexyl) terephthalate, and di-n-octyl phthalate were not detected in the e-liquids. Some of the other evaluated phthalates were present at trace levels in certain e-liquids while most e-liquids did not contain phthalates at detectable levels.

Determination of phthalate esters in distillates by ultrasound-vortex-assisted dispersive liquid-liquid micro-extraction (USVADLLME) coupled with gas chromatography/mass spectrometry

A method for the extraction of phthalate esters (PAEs) by Ultrasound-Vortex-Assisted Dispersive Liquid-Liquid Micro-Extraction (USVADLLME) approach was optimised and applied for the first time to a historical series of brandies. These contaminants are widely spread in the environment as a consequence of about half century of use in different fields of applications. The concern about these substances and the recent legal restrictions of China in distillates import need a quick and sensitive method for their quantification. The proposed method, moreover, is environmentally oriented due to the disposal of micro-quantities of solvent required. In fact, sub-ppm-limits of detection were achieved with a solvent volume as low as 160μL. The analysed samples were within the legal limits, except for some very ancient brandies whose contamination was probably due to a PAEs concentration effect as a consequence of long ageing and for the use of plastic pipelines no more operative.

Dispersive Liquid-Liquid Microextraction in the Analysis of Milk and Dairy Products: A Review

Dispersive liquid-liquid microextraction (DLLME) is an extraction technique developed within the last decade, which involves the dispersion of fine droplets of extraction solvent in an aqueous sample. Partitioning of analytes into the extraction phase is instantaneous due to the very high collective surface area of the droplets. This leads to very high enrichment factors and very low solvent consumption, relative to other liquid or solid phase extraction methods. A comprehensive review of the various modes of DLLME in the analysis of organic and inorganic analytes in dairy products (milk, cheese, infant formula, yogurt, and breast milk) is presented here. Dairy products present a complex sample matrix and the removal of interfering matrix components can prove troublesome. This review focuses on sample pretreatment prior to the appropriate DLLME procedure, the extraction and dispersive solvents chosen, derivatisation methods, and analytical figures of merit. Where possible, a critical comparison of DLLME methods has been undertaken. The overall suitability, and limitations, of DLLME as a sample preparation technique for dairy products has been assessed.