Di-n-octyl Phthalate Research Articles

Method development for determination of migrated phthalate acid esters from polyethylene terephthalate (PET) packaging into traditional Iranian drinking beverage (Doogh) samples: a novel approach of MSPE-GC/MS technique.

In the current study, a novel magnetic solid phase extraction (MSPE) technique combined with a gas chromatography/mass spectroscopy (GC/MS) was developed to determine the phthalate ester content of bottled Doogh samples. Doogh is a yogurt-based drinking beverage, which is frequently consumed in Middle East and Balkans. It is produced by stirring yogurt in Chern separation machine and consists of substances such as water, yogurt, and salt in addition to aqueous extracts of native herbs. The magnetic multi-walled carbon nanotubes (MWCNT-Fe3O4) were used as adsorbents of phthalate acid esters (PAEs) due to a superior adsorption capability of hydrophobic compounds. In this context, the quantity of the extractable migrated phthalate esters (dibutyl phthalate (DBP), dimethyl phthalate (DMP), butyl benzyl phthalate (BBP), diethyl phthalate (DEP), di-N-octyl phthalate (DNOP), and bis (2-ethylhexyl) phthalate (DEHP)) from polyethylene terephthalate (PET) bottles into Doogh samples was measured. The correlation between the concentration of migrated PAEs and some factors such as the type of Doogh (gaseous and without gas), difference in brand (five brands), volume (1500 and 300mL), and the storage time also was investigated. The migration level into Doogh samples was increased by incorporating of gas as well as increasing the volume of PET bottles. Also, with elaborating of storage time, the migration of some phthalates such as DEHP (the mean from 2419.85ngL-1 in the first week to 2716.15ngL-1 in the second month), DEP, and total phthalate was increased. However, no significant difference in concentrations of migrated phthalate esters among different examined brands was noted. Finally, the concentration of migrated PAEs from bottle into all the examined Doogh samples was below the defined standards by EPA; 6μg/L for DEHP in drinking water. Graphical abstract ᅟ.

Human Milk Phthalate Diester Levels in Turkey

Introduction: Newborn and infants are among the most susceptible age groups to endocrine disruption due to potential environmental toxins like phthalates. Differing results have been found on phthalate exposure through human milk from different geographic parts of the world. In this study, we aim to evaluate six different phthalate diesters in human milk samples. Methods: In this part of the Human Milk Artificial Pollutants (HUMAP) study, human milk samples were analyzed using GC-MS to indicate the presence of bis (2-ethylhexyl) phthalate (DEHP), benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), di-“isononyl” phthalate (DINP), di-“isodecyl” phthalate (DIDP), and di-n-octyl phthalate (DNOP). Results: This study included 72 mothers aged 18 to 41 years; human milk samples were taken from the mothers who gave their consent to participate within 7 to 79 days after birth (mean 34 ± 20 days). We did not detected phthalate esters as DEHP, BBP, DBP, DINP, DIDP, and DNOP in 72 human milk samples. Discussion: In this study, we did not find phthalate diesters in human milk samples in Turkey. Different results of previous studies about human milk phthalate levels might be related to geography, maternal factors, or analytical methods. In conclusion, potential further studies should continue for potential chemical contamination of human milk.

Simultaneous determination of eight phthalate ester plasticizers in sports beverages using supercritical fluid chromatography

Phthalate esters (PAEs) are a group of serious environmental pollutants that are carcinogenic or tumorigenic to humans. In this work, a green, rapid, and effective analytical method based on supercritical fluid chromatography (SFC) has been proposed for the simultaneous determination of the eight PAE plasticizers in sports beverage samples. They are dimethyl phthalate (DMP), diethyl phthalate (DEP), dipropyl phthalate (DPRP), dibutyl phthalate (DBP), dipentyl phthalate (DPP), benzyl butyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DNOP). Liquid phase extraction (LPE) was employed to extract the PAE plasticizers before testing using SFC with ultraviolet (UV) detection. SFC parameters, including stationary phase screening, modifier composition and volume percentage, column temperature, flow rate, and backpressure, were optimized. Under the optimum conditions, all the eight PAE plasticizers could be determined simultaneously by SFC within 6 min at 225 nm. The optimized eluent was supercritical CO2 with 3% (v/v) methanol. The performance of the developed method was also evaluated. The eight PAE plasticizers exhibited satisfactory linearities with correlation coefficients (r) of 0.9991-0.9997 in the range of 0.05-25 mg/L. The limits of detection ranged from 7.5 to 15 μg/L (S/N=3, n=3). Recoveries of all the PAE plasticizers for the spiked samples ranged from 91.7%-100.2% with relative standard deviations of no more than 6.5% (n=3). This method is green, time-saving, simple, selective, robust, and convenient for the analysis of the eight PAE plasticizers in real sports beverage samples.

Development and Validation of Gas Chromatography-Triple Quadrupole Mass Spectrometric Method for Quantitative Determination of Regulated Plasticizers in Medical Infusion Sets.

A method for the quantitative determination of dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), bis(2-ethylhexyl) adipate (DEHA), bis(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP), dioctyl terephthalate (DOTP), diisononyl phthalate (DINP), and diisodecyl phthalate (DIDP) in medical infusion sets was developed and validated using gas chromatography coupled with triple quadrupole mass spectrometry (GC-MS/MS) in the multiple reaction monitoring (MRM) mode. Solvent extraction with polymer dissolution for sample preparation was employed prior to GC-MS/MS analysis. Average recoveries of the eight target analytes are typically in the range of 91.8–122% with the relative standard deviations of 1.8–17.8%. The limits of quantification (LOQs) of the analytical method were in the ranges of 54.1 to 76.3 ng/g. Analysis using GC-MS/MS provided reliable performance, as well as higher sensitivity and selectivity than GC-MS analysis, especially for the presence of minority plasticizers at different concentrations.

Dietary exposure of the Chinese population to phthalate esters by a Total Diet Study

Dietary exposure to phthalate esters (PAEs) was assessed for the general Chinese population in the 5th Chinese Total Diet Study (TDS). Concentrations of 16 PAEs, including bis (2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), butylbenzyl phthalate (BBP), diethyl phthalate (DEP), dimethyl phthalate (DMP), diisobutyl phthalate (DIBP), bis (2-n-butoxyethyl) phthalate (DBEP), bis (2-ethoxyethyl) phthalate (DEEP), bis (2-methoxyethyl) phthalate (DMEP), bis (4-methyl-2-pentyl) phthalate (BMPP), dicyclohexyl phthalate (DCHP), dipentyl phthalate (DPP), diphenyl phthalate (DPhP), di-n-hexyl phthalate (DHXP), dinonyl phthalate (DNP), di-n-octyl phthalate (DNOP) were determined in 192 composite food samples collected from the TDS. The results showed that 76.0% of the samples contained one or more PAEs with concentrations ranging from 0.017 to 7.19 mg/kg. The most frequently detected PAEs were DEHP (43.8%), DBP (35.9%), DMP (26.6%), DNP (25.5%), DIBP (24.5%), and DCHP (18.8%). The major dietary source of PAEs was vegetables, followed by cereals. A dietary exposure of the general population was assessed using lower bound (LB) and upper bound (UB) assumptions for left-censorship management. The average estimated daily intakes of PAEs in the general Chinese population ranged from 0.00 to 6.38 μg/kg bw per day, which were lower than the respective tolerable daily intakes (TDIs) of PAEs. The results suggested that dietary exposures to all of the PAEs analyzed in this study were unlikely to pose unacceptable health risks to the majority of the population in China.

Di-N-octylphthalate acts as a proliferative agent in murine cell hepatocytes by regulating the levels of TGF-β and pro-apoptotic proteins

Di-n-octylphthalate (DNOP) is a phthalate used in the manufacturing of a wide variety of polyvinyl chloride-containing medical and consumer products. A study on chronic exposure to DNOP in rodents showed the development of pre-neoplastic hepatic lesions following exposure to a tumor initiator. The objective of this study was to identify the mechanisms by which DNOP leads to pre-neoplastic hepatic lesions. Mouse hepatocyte AML-12 and FL83B cells were treated with DNOP. The rate of cell proliferation was increased in treated cells in a concentration-dependent manner. DNOP increased the expression of transforming growth factor-β (tgf-β) in both cell lines, and primary culture mouse hepatocytes. The TGF-β receptor inhibitor LY2109761 impaired the effect of DNOP. The presence of pro-apoptotic proteins decreased in the presence of DNOP. Our observation indicates that DNOP, through an increase in the expression of tgf-β and a decrease in the levels of pro-apoptotic proteins, acts as a proliferative agent in normal mouse hepatocytes. We also studied the morphological and functional changes of the mouse liver upon a short-term treatment of DNOP. Mice exposed to DNOP displayed an epithelial-to-mesenchymal transition and cholestasis, which was reflected in an increase in hepatic bile acids and glutathione levels.

Concentrations of several phthalates contaminants in Egyptian bottled water: Effects of storage conditions and estimate of human exposure

The occurrence and concentrations of six common phthalates were investigated for the first time in bottled water locally produced in the Egyptian market. The compounds investigated were dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), n-butyl benzyl phthalate (BBP), diethyl hexyl phthalate (DEHP), and Di-n-octyl phthalate (D-n-OP). A set of 108 bottled water samples from six different commercial brands of water bottled in transparent polyethylene terephthalate (PET) plastic bottles with high density polyethylene (HDPE) plastic caps were investigated. Water samples were analyzed immediately after purchasing (~2weeks after production), after being stored at room temperature (25±5°C), in a refrigerator (4±1°C) and outdoor under sun exposure (daylight temperature of 40±5°C). Samples were stored up to six months depending on the tested condition. Among the target compounds, only DEHP and DBP were detected in the samples analyzed immediately after purchasing with a detection frequency of 50 and 58% and mean concentrations of 0.104 and 0.082μgl−1 respectively. Significant positive correlation was obtained between the storage time, temperature and the concentration of phthalate compounds detected in the bottled water, indicating possible migration from the PET plastic material as the source. The estimated contribution of bottled water consumption to the tolerable daily intake (TDI) levels of the two most abundant phthalates observed here for adults and toddlers did not exceed 0.16 and 0.72% for DBP while these values were 0.04 and 0.16% for DEHP respectively. These estimated daily intake values from PET bottled water consumption were far below their respective TDI values and therefore should constitute no adverse health effects.

Determination of phthalic acid esters in water samples using core-shell poly(dopamine) magnetic nanoparticles and gas chromatography tandem mass spectrometry

In this work, the first application of core-shell poly(dopamine) magnetic nanoparticles as sorbent for the extraction of a group of eleven phthalic acid esters of interest (i.e. diethyl phthalate (DEP), dipropyl phthalate (DPP), dibutyl phthalate (DBP), bis-isopentyl phthalate (DIPP), bis-n-pentyl phthalate (DNPP), benzylbutyl phthalate (BBP), dicyclohexyl phthalate (DCHP), di-(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP)) and one adipate (bis (2-ethylhexyl) adipate, DEHA) from different water samples (Milli-Q, mineral, tap, pond and waste water) is proposed. Analysis were carried out by gas chromatography triple quadrupole tandem mass spectrometry. Parameters that affect the extraction performance were optimized following a step by step approach, being the optimum conditions the extraction of water at pH 6, with 60mg of sorbent and the elution with 6mL of dichloromethane. The methodology was validated for the five selected water samples using DBP-d4 as internal standard. Determination coefficients of matrix-matched calibration curves were above 0.9904 in all cases while relative recovery values ranged between 71 and 120%, with relative standard deviation values below 19%. The limits of quantification of the method ranged between 9 and 20ng/L. Matrix effects were found for most analytes and water samples. Real water samples were also analyzed, finding DEP and DBP at concentrations below 4.20 and 1.23μg/L, respectively, in mineral, tap and waste water. DCHP, DEHP and BBP were also found in some of the samples at concentrations below the LOQs of the method.

Magnetic covalent triazine framework for rapid extraction of phthalate esters in plastic packaging materials followed by gas chromatography-flame ionization detection

Covalent triazine frameworks (CTFs), featuring with high surface area, good thermal, chemical and mechanical stability, are good adsorbents in sample pretreatment. Herein, magnetic CTFs/Ni composite was prepared by in situ reduction of nickel ions on CTFs matrix with a solvothermal method. The prepared CTFs/Ni composite exhibited good preparation reproducibility, high chemical stability, and high extraction efficiency for targeted phthalate esters (PAEs) due to π-π interaction and hydrophobic effect. The porous structure of CTFs/Ni composite benefited the fast transfer of target PAEs from aqueous solution to the adsorbents, and the integrated magnetism contributed to the rapid separation of adsorbents from sample and elution solution. Based on it, a novel method of magnetic solid phase extraction (MSPE) combined with gas chromatography-flame ionization detector (GC-FID) was developed for the analysis of PAEs including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2-ethylhexl phthalate (DEHP), and di-n-octyl phthalate (DNOP) in plastic packaging materials. Under the optimal experimental conditions, the limits of detection (LODs, S/N=3) for six PAEs were found to be in the range of 0.024-0.085mg/kg. The linear range was 0.32–16mg/kg for DMP, DEP, 0.08–80mg/kg for DBP, 0.16–32mg/kg for BBP, DEHP, and 0.32–32mg/kg for DNOP, respectively. The enrichment factors ranged from 59 to 88-fold (theoretical enrichment factor was 133-fold). The proposed method was successfully applied to the analysis of PAEs in various plastic packaging materials with recoveries in the range of 70.6-119% for the spiked samples. This method is characterized with short operation time, high sensitivity, low consumption of harmful organic solvents and can be extended to the analysis of other trace aromatic compounds.

Packed-Nanofiber solid phase extraction coupled with gas chromatography-mass spectrometry for the determination of phthalate esters in urines from children.

In this paper, we developed a rapid and safe method based on packed-fiber solid-phase extraction (PFSPE) system coupled with gas chromatography-mass spectrometry for the determination of four phthalate esters (PAEs), diethyl-o-phthalate (DEP), dibutyl-o-phthalate (DBP), di (2-ethylhexyl) phathalate (DEHP), di-n-octyl phthalate (DNOP), in urine samples. The PAEs in urine samples (500μL) were rapidly cleaned up from urines using polystyrene (PS) nanofibers packed micro-columns fitted on a PFSPE pretreatment device, which can process up to 12 samples simultaneously in 5min. Under optimum conditions, satisfied recovery and relative standard deviation values (RSDs) were in the range of 80.4-111.7% and 1.5-10.9%, respectively. The limits of detection (LOD) and the limits of quantification (LOQ) were ranged from 0.1 to 0.5ngmL-1 and 0.5-2ngmL-1, respectively. The well controlled matrix effect was also evaluated by comparing the signal response of the pure PAEs standards dissolved in methanol with the signal response of PAEs in the urine matrix. This new method was successfully applied to determine four PAEs in urine samples of overweight and normal-weight children, and an association between phthalates in urines and obesity was observed. Thus, the method seems to be a useful tool for monitoring of the level of urinary phthalate esters and also to support an evidence for further reasearch of obesity.

Phthalate Sample Preparation Methods and Analysis in Food and Food Packaging: a Review

A review on phthalate esters or phthalic acid esters (PAEs), chemicals of concern since a few decades ago that are widely used as plasticizers in food processing and packaging, is presented taking into account the background of such compounds, the metabolism, human exposure to PAEs, the sources and occurrence in food as well as the toxicological aspects and human health effects. In addition, 45 novel research articles that were published between 2002 and 2017 were identified and their results were tabulated showing the PAEs analysed, food matrix of PAEs, methods of sample preparation/extraction, methods of instrumental analysis and quantitation, percentage recovery and limit of detection (LOD) of the instrument for ease of comparison and referencing. In general, it was found that in the last 15 years, the number of PAEs analysed has increased from the commonly analysed 8 PAEs, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), dicyclohexyl phthalate (DCHP), di-n-octyl phthalate (DNOP) and di-(2-ethylhexyl) phthalate (DEHP) to as many as 23 PAEs. The methods of sample preparation have also progressed from the simple liquid-liquid extraction using organic solvents to solid-phase microextraction techniques to the more recent head-space or direct immersion solid-phase microextraction methods. Whereas for the analysis of PAEs, gas chromatography and liquid chromatography are still the preferred methods with improved LOD of analysis ranging from approximately 10 ppm for fatty foods to 1–60 ppt for water, juices and cooking oil samples.

Dummy molecularly imprinted microbeads as solid-phase extraction material for selective determination of phthalate esters in water

The aim of this study was to investigate the usability of newly synthesized dummy molecularly imprinted microbeads (DMIMs) as a solid phase extraction (SPE) material to determine six phthalate esters (PEs) in water by GC–MS analysis. Diethyl phthalate (DEP) was used as a dummy template to prepare poly(ethylene glycol dimethacrylate N-methacryloyl-l-tryptophan methyl ester) [PEMATrp)] DMIMs by using suspension polymerization. The PEMATrp DMIMs were characterized by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Firstly, the adsorption capacities of the DMIMs prepared in different template molecule (DEP) to functional monomer (MATrp) ratios were investigated by using DEP solutions in the concentration range of 1–500mg/L at pH 3.0. Styrene and vanillic acid were used to evaluate the selectivity of the prepared DMIMs towards the template molecule (DEP). Then, the best analytical conditions were investigated for the simultaneous determination of dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzylbutyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) in aqueous media by using the PEMATrp DMIMs as SPE material. Validation experiments showed that the PEMATrp DMIMs-SPE method had good linearity at 12.5–250.0μg/L (0.988–0.999), good precision (1.2–5.9%), and limits of detection in a range of 0.31–0.41μg/L.

Determination of Phthalate Residues in Different Types of Yogurt by Gas Chromatography-Mass Spectrometry and Estimation of Yogurt-Related Intake of Phthalates

Phthalates are potential endocrine-disrupting chemicals, found widely in the environment, and commonly used to make plastics softer and more flexible. Little information is available about the presence of phthalates in yogurt products sold on the world market. This study aimed to develop a sensitive GC-MS method for the determination of selected phthalates in yogurt and residue levels in fruit yogurts together with the packaging materials and to estimate a yogurt-related exposure to phthalates in the Turkish population. Acetonitrile extraction followed by cleanup procedures using different adsorbents yielded relatively clean extracts. The presence as the percent of selected phthalates tested—dibutyl phthalate (DBP), diethylhexyl phthalate (DEHP), dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-octyl phthalate (DNOP), and benzyl butyl phthalate (BBP)—were determined as 76, 70, 70, 54, 20, and 8% of the samples, respectively, for the phthalates, ranging from <LOQ to 1640 μg/kg. The highest concentrations were found in cherry yogurt among the fruit yogurts, while banana and pineapple yogurts contained the least. The results indicate that the estimated daily intakes for phthalates were below tolerable daily intakes.

Phthalate esters in settled dust of different indoor microenvironments; source of non-dietary human exposure

This study reports levels and profiles of phthalates in dust samples collected from three different microenvironments (cars, air conditioner (AC) filters and household floor dust) of Saudi Arabia (KSA) and Kuwait. To the best of our knowledge, this is a very first study in the literature reporting phthalates in the indoor environments of KSA, which makes these findings very important. Our results showed that bis(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), di-isobutyl phthalate (DIBP), and di-n-octyl phthalate (DNOP) were the major chemicals in all dust samples. DEHP was the overwhelming compound in all microenvironments occurred at median concentrations (μg/g) of 1020, 1250, and 790 in Saudi household floor, car, and AC filter dust, respectively. The median levels (μg/g) of DEHP in Kuwaiti car (320) and household floor (240) dust samples were 3–4 times lower than respective Saudi dust. Phthalates were higher in car dust than household dust and Ac filter dust, suggesting people spending more time in vehicles are at higher risk of exposure to these chemicals. Different exposure scenarios, using 5th percentile, median, mean, and 95th percentile levels, were estimated for adults and toddlers. For Saudi and Kuwaiti toddlers worst exposure scenario for DEHP, a cardiotoxic and endocrine disruptor, was calculated at 37630 and 6722ng/kg body weight/day (ng/kg bw/d), respectively. This preliminary study provided first-hand baseline data of Phthalates from Gulf countries and which necessitate more detailed future studies in this region. Practical implicationsThe first study on the incidence of phthalates from different micro–environments of KSA. High levels of bis(2-ethylhexyl) phthalate (DEHP) were present in Kuwaiti and KSA indoor micro–environments suggesting a high use of DEHP in consumer products. Exposure to phthalates via dust ingestion is estimated high in Saudi toddlers, which is a cause of concern.

Effects of six priority controlled phthalate esters with long-term low-dose integrated exposure on male reproductive toxicity in rats

Human beings are inevitably exposed to ubiquitous phthalate esters (PEs) surroundings. The purposes of this study were to investigate the effects of long-term low-dose exposure to the mixture of six priority controlled phthalate esters (MIXPs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethyhexyl) phthalate (DEHP) and di-n-octyl phthalate (DNOP), on male rat reproductive system and further to explore the underlying mechanisms of the reproductive toxicity. The male rats were orally exposed to either sodium carboxymethyl cellulose as controls or MIXPs at three different low-doses by gavage for 15 weeks. Testosterone and luteinizing hormone (LH) in serum were analyzed, and pathological examinations were performed for toxicity evaluation. Steroidogenic proteins (StAR, P450scc, CYP17A1 and 17β-HSD), cell cycle and apoptosis-related proteins (p53, Chk1, Cdc2, CDK6, Bcl-2 and Bax) were measured for mechanisms exploration. MIXPs with long-term low-dose exposure could cause male reproductive toxicity to the rats, including the decrease of both serum and testicular testosterone, and the constructional damage of testis. These effects were related to down-regulated steroidogenic proteins, arresting cell cycle progression and promoting apoptosis in rat testicular cells. The results indicate that MIXPs with long-term low-dose exposure may pose male reproductive toxicity in human.

Exposure Marker Discovery of Phthalates Using Mass Spectrometry.

Phthalates are chemicals widely used in industry and the consequences on human health caused by exposure to these agents are of significant interest currently. The urinary metabolites of phthalates can be measured and used as exposure markers for the assessment of the actual internal contamination of phthalates coming from different sources and absorbed by various ways. The purpose of this paper is to review the markers for exposure and risk assessment of phthalates such as di-methyl phthalate (DMP), di-ethyl phthalate (DEP), di-butyl phthalate (DBP), benzylbutyl phthalate (BBP), di-(2-ethylhexyl)phthalate (DEHP), di-(2-propylheptyl)phthalate (DPHP), di-iso-nonyl phthalate (DINP), di-n-octyl phthalate (DnOP) and di-iso-decyl phthalate (DIDP), and introduction of the analytical approach of three metabolomics data processing approaches that can be used for chemical exposure marker discovery in urine with high-resolution mass spectrometry (HRMS) data.

Phthalate Esters on Hands of Office Workers: Estimating the Influence of Touching Surfaces

Phthalate esters (PAEs) are known to be transferred to hands by contact with surfaces, however, little is known about the associations between masses on hand wipes and the frequency or duration of touching surfaces, especially surfaces in office environments. Relationships between PAEs on hands and multiple surfaces in offices were investigated. Wipes of hands, computers, and mobile phones as well as dust on furniture were collected from 55 offices in China. Positive associations were found between masses of di-2-ethylhexyl phthalate (DEHP), dibutyl phthalate (DnBP), benzyl butyl phthalate (BBP), and di-n-octyl phthalate (DnOP) on wipes of hands and wipes of keyboards of computers. When workers used keyboards with polymer covers (dust covers), masses of these lipophilic PAEs on hands were significantly correlated with masses on keyboards rather than dust on furniture. For workers who used keyboards without polymer covers, masses on hands were related to masses in dust on furniture. Use of polymer covers c...

In vitro and in silico investigations of the binary-mixture toxicity of phthalate esters and cadmium (II) to Vibrio qinghaiensis sp.-Q67.

Phthalate esters (PAEs) are widely used as plasticizers and have become one of the emerging contaminants with an increasing public concern. The residues of PAEs frequently co-exist with heavy metals such as cadmium (Cd) in waters; however, their joint ecotoxicity remains largely unknown. We herein investigated the single and joint toxicity of commonly used PAEs and Cd using freshwater luminescent bacteria Vibrio qinghaiensis sp.-Q67. The median effective concentration (EC50) of benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP), diisooctyl phthalate (DIOP) and di-n-octyl phthalate (DOP) were determined to be in the range from 134.4mg/L to as high as 1000mg/L, indicating very weak toxicity to Vibrio qinghaiensis sp.-Q67. The toxicity of single PAEs showed a significant linear relationship with Log Kow, indicating the dependence of the elevated toxicity on the increasing hydrophilicity. The toxicity of binary mixture of PAEs was further evaluated in silico using the independent action (IA) model and concentration addition (CA) model. DMP-DEP, DEP-DBP or DMP-DBP exhibited antagonistic effects with the toxic unit value higher than 1.2. The CA and IA models poorly predicted the joint toxicity of DMP-DEP, DEP-DBP or DMP-DBP. The joint toxicity of the binary mixtures of DMP, DEP or DBP with Cd was simple additive as predicted by the CA and IA models. Our results indicated the potentially higher risk of PAEs in the presence of Cd, emphasizing the importance of determining the impact of their joint effects on aquatic organisms. The integrated in vitro and in silico methods employed in this study will be beneficial to study the joint toxicity and better assess the aquatic ecological risk of PAEs.

Ionic Liquid-Based Surfactant Extraction Coupled with Magnetic Dispersive μ-Solid Phase Extraction for the Determination of Phthalate Esters in Packaging Milk Samples by HPLC

A highly selective sample cleanup procedure combining ionic liquid-based surfactant extraction (ILSE) and magnetic dispersive μ-solid phase extraction (MD-μ-SPE) was triumphantly developed for the synchronously extraction of four phthalate acid esters (PAEs) in packaging milk samples prior to high-performance liquid chromatography coupled with photodiode array detector (HPLC-DAD). In this ionic liquid (IL)-based surfactant method, 1-octyl-3-methylimidazolium hexafluorophosphate ([C8MIM] [PF6]) was used as extraction solvent, anionic surfactant sodium linear alkylbenzene sulfonate (LAS) was used as auxiliary extraction solvent, and then sodium chloride (NaCl) was mixed to drive phase separation. The synthesized hydrophobic diatomaceous earth-supported Fe3O4 magnetic nanoparticles (DSMNPs) were applied as an efficient adsorbent to retrieve the analyte-containing IL and LAS. Under the optimal extraction situations, good linearity of the approach was obtained in the concentration range from 10 to 1000 ng/mL for target analytes, and the preconcentration process was rapidly accomplished in 5 min. The limits of detection (LODs) based on a signal-to-noise ratio (S/N = 3) were ranged from 1.42 to 3.57 ng/mL with the relative standard deviations (RSDs) over the range of 1.84–3.56% (n = 5). The above-mentioned method was applied to the trace analysis of four PAEs including benzyl butyl phthalate (BBP), dicyclohexyl phthalate (DCHP), di-n-butyl phthalate (DBP), and di-n-octyl phthalate (DNOP) in packaging milk samples, and recoveries were between 89.8 and 99.7%.

Transfer of phthalates from c-polyvinyl chloride and cross-linked polyethylene pipe (PEX-b) into drinking water

Several different materials have been used for production of domestic water pipes throughout history. In recent years, the use of cross-linked polyethylene (PEX) pipe has increased dramatically, yet the potential for leaching of phthalates, which are endocrine disrupting compounds associated with adverse reproductive effects in humans, has not been examined. In this study, the potential of chlorinated polyvinyl chloride (cPVC) and red, blue, and heat PEX piping to leach phthalates into static hot and cold water after 2, 8, and 48 hours was evaluated. Concentrations of six phthalates, dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), benzyl-butyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), and di(n-octyl) phthalate (DNOP), were determined by gas chromatography-mass spectrometry. Pipe type (F3,71 = 15.6, P = 0.001) contributed significantly to phthalate concentrations in water, while temperature (F4,71 = 1.74, P = 0.106) and time (F4,71 = 1.02, P = 0.427) were not significant factors. Significantly higher concentrations of DEP, DBP, and BBP were observed in cPVC pipe (&amp;lt;method detection limits (MDL) to 466 ng L−1, 252–4,219 ng L−1, 473–18,400 ng L−1, respectively) compared to blue PEX (T2 = 12.2, P &amp;lt; 0.001; &amp;lt;MDL, &amp;lt;MDL − 140 ng L−1, &amp;lt;MDL − 459 ng L−1, respectively), red PEX (T2 = 19.3, P &amp;lt; 0.001; &amp;lt;MDL, &amp;lt;MDL − 188 ng L−1, &amp;lt;MDL − 881 ng L−1, respectively), and heat PEX (T2 = 19.9, P &amp;lt; 0.001; &amp;lt;MDL, &amp;lt;MDL − 162 ng L−1, &amp;lt;MDL − 169 ng L−1, respectively). Phthalate exposure from drinking water via cPVC or PEX is low when compared to other dietary sources. Nonetheless, a shift from cPVC to PEX pipes in households would decrease potential exposure to phthalates.