Sorption studies of phthalic acid esters uptake from lagos lagoon sample using characterized gmelina arborea pericarp biosorbent

A total of 58 surface dust samples were collected in urban area of Xi'an City. High Performance Liquid Chromatography (HPLC) was used to analyze the concentrations of six phthalic acid esters (PAEs) listed as priority pollutants by United States Environmental Protection Agency (U.S. EPA). Composition, distribution, environmental sources and exposure characteristics of PAEs in the surface dust were further studied. All analyzed PAEs were detected in the surface dust. The concentration of individual PAE compounds varied from not detectable to 183.19 mg·kg-1 and their mean concentrations decreased in the order of DEHP>DnBP >>DEP >DMP >BBP >DnOP. The total concentration of six PAEs (∑6PAEs) ranged from 0.87 to 250.30 mg·kg-1 with an average of 40.48 mg·kg-1, and followed the order of parks >traffic area >mixed business and traffic area >residential area >educational area >industrial area. The ∑6PAEs presented the decreasing trend along the main urban area - the second ring road - the third ring road. The results of correlation analysis, principal component analysis and cluster analysis showed that PAEs in surface dust of Xi'an City were related to the application of plasticizers, the emission of cosmetics and personal care products along with building materials and home decoration materials. The dose order of human exposure to PAEs in surface dust was the direct ingestion by hand and mouth >>dermal adsorption >inhalation via mouth and nose. Meanwhile, the intake dose of children was higher than that of adults. However, the intake dose of DnBP, DEHP, DBP and BBP was lower than the tolerable daily intake (TDI) suggested by European Union Scientific Committee for Toxicity, Ecotoxicity and the Environment (EU CSTEE) and the reference doses (RfD) proposed by U.S. EPA.

In this study, High Performance Liquid Chromatography (HPLC), combined with Triple Quadruple mass Spectrometry (QQQ) were developed and applied in the analysis of 16 phthalic acid esters (PAEs) in the common drinking water. Qualitative and quantitative analysis were carried out by Multiple Reaction Monitoring (MRM). The method, combined with Solid Phase Extraction, was established to detect the PAEs in drinking water. As showed by the results, 16 PAEs had a good linearity in the range of 1.14~101.4μg/L, with correlation coefficient between 0.996~0.999. The mean recoveries were in the range of 87.53~131.37%, with the relative standard deviation be 0.71~5.09%. The limit of quantification (LOQ) of 16 PAEs were between 1.14~32.51μg/L, with the limit of detection (LOD) be 0.34~10.67μg/L. There were five PAEs which were detected in the range of <1.7~17.2μg/L in bottled water. Some products have some PAEs which havent been shown in the national or the international standard of the drinking water.

Distribution and sources of polycyclic aromatic hydrocarbons and phthalic acid esters in water and surface sediment from the Three Gorges Reservoir

Multi-walled carbon nanotubes modified with iron oxide and silver nanoparticles (MWCNT-Fe3O4/Ag) as a novel adsorbent for determining PAEs in carbonated soft drinks using magnetic SPE-GC/MS method

A simple, rapid and low cost method for determination of phthalic acid esters (PAEs) including Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Di-n-butyl phthalate (DBP) and Butylbenzyl phthalate (BBP) in water samples was investigated. The method is based on the extraction of PAEs with coacervate made up of decanoic acid reverse micelles and the subsequent determination by HPLC-UV. Effect of parameters such as concentration of tetrahydrofuran (THF) (2–40% v/v) and decanoic acid (20–400 mg in 40 ml total volume), ionic strength (0.0–0.1 M NaCl), pH (1–4) and stirring time (2–60 min) on recoveries (Rs) and enrichment factors (EFs) were investigated and optimized. The optimum condition for extraction was the stirring of 36 ml of water sample with 4 ml of THF containing 100 mg of decanoic acid for 10 min and its centrifugation (10 min, 3500 rpm). Recoveries and enrichment factors of PAEs mainly depended on the amount of decanoic acid and THF making up the coacervate and were not affected by ionic strength of the sample solution (up to 0.1 M of NaCl), pH (1–4), and stirring time (2–60 min). Recoveries, enrichment factors, LODs and relative standard deviations (RSD%) for PAEs were between 87–94%, 187–202, 0.22–0.30 μg l−1 and 2–5%, respectively. This method was applied to determine PAEs in tap water, river water, and sea water samples. No PAEs were found in tap water. The amount of DMP and DEP in the Babolrood River was 0.87 and 0.67 μg l−1, while in the Caspian Sea was 0.49 and 0.52 μg l−1, respectively.

Phthalic acid esters (PAEs) are well-known ubiquitous environmental pollutants and used as plasticizers for the manufacturing of plastic products. During this exploratory study, an attempt has been made to determine the concentration and distribution of five prominent PAEs, viz. di-methyl phthalate (DMP), di-ethyl phthalate (DEP), di-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), and di-octyl phthalate (DOP) in the sediment samples of Gomti River collected from 30 different locations. Identification and quantification of PAEs were performed by high-performance liquid chromatography. The mean concentration values of DMP, DEP, DBP, DEHP, and DOP were found as 10.54, 4.57, 10.41, 31.61, and 5.16 microg/kg, respectively. Limit of detection and limit of quantification for each PAE were also calculated and found in the ranges of 0.09-0.55 and 0.28-1.67 microg/kg. DEHP was the most frequently detected PAE (present in 93.3% samples); however, DOP was found only in 36.7% samples.

Thickness-dependent release of microplastics and phthalic acid esters from polythene and biodegradable residual films in agricultural soils and its related productivity effects

Carbon nanotube composite microspheres as a highly efficient solid-phase microextraction coating for sensitive determination of phthalate acid esters in water samples

A gold nanoparticle-quenched graphene quantum dot-based aptasensor was developed to perform clustered detection of 11 phthalic acid esters (PAEs). The binding of the target PAEs to the aptasensor frees the graphene quantum dots that are otherwise quenched by the carrier gold nanoparticle. The resultant fluorescence upon excitation is proportional to the number of freed graphene quantum dots and hence the target PAE concentration. The synthesis of the proposed aptasensor was first verified step-by-step via FT-IR measurement, scanning electron microscopy, and fluorescence measurement. Selectivity was evaluated for individual and combined target PAEs and compared against seven non-PAE endocrine disrupting compounds. The proposed aptasensor successfully quantified 11 PAEs in test samples with varying concentrations of 0.001-50 ng PAEs/mL and demonstrated a limit of detection of ∼4 pg./mL. Finally, the AuNP-gQD aptasensor was employed to detect multiple combinations of commonly regulated PAEs (DBP, DIBP, DEHP, and BBP). The recovery (%) for all four PAEs combination in environmentally relevant concentrations of 0.5, 1, 5, and 10 ng/mL were ∼100%.

A sensitive, rapid, and simple high-performance liquid chromatography with UV detection method was developed for the simultaneous determination of seven phthalic acid esters (dimethyl phthalate, dipropyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, dicyclohexyl phthalate, di-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in several kinds of beverage samples. Ultrasound and vortex-assisted dispersive liquid-liquid microextraction method was used. The separation was performed using an Intersil ODS-3 column (C18 , 250 × 4.6 mm, 5.0 μm) and a gradient elution with a mobile phase consisting of MeOH/ACN (50:50) and 0.2 M KH2 PO4 buffer. Analytes were detected by a UV detector at 230 nm. The developed method was validated in terms of linearity, limit of detection, limit of quantification, repeatability, accuracy, and recovery. Calibration equations and correlation coefficients (> 0.99) were calculated by least squares method with weighting factor. The limit of detection and quantification were in the range of 0.019-0.208 and 0.072-0.483 μg/L. The repeatability and intermediate precision were determined in terms of relative standard deviation to be within 0.03-3.93 and 0.02-4.74%, respectively. The accuracy was found to be in the range of -14.55 to 15.57% in terms of relative error. Seventeen different beverage samples in plastic bottles were successfully analyzed, and ten of them were found to be contaminated by different phthalic acid esters.

Biosorption kinetics, thermodynamics and isosteric heat of sorption of Cu(II) onto Tamarindus indica seed powder

Phthalic acid ester (PAE), a plasticizer, is increasingly being detected in different environments. These compounds can gravely affect the human endocrine system. The present study aims to prepare adsorbents that can effectively adsorb PAE pollutants. To fabricate a better carbon structure than conventional biochar, the sodium hydroxide solution was used as a hydrolyzing agent to pretreat the biomass in order to weaken the bonds in lignin, cellulose, and hemicellulose. As a result, biochar with a special porous carbon structure is obtained. To study the characteristics of the biochar and its adsorption properties, dimethyl phthalate (DMP)—a PAE—was selected as the adsorbate. The morphology and structural composition of the biochar were examined via an environment scanning electron microscope with a field emission gun (SEM), surface area analyzer (BET), Fourier transform infrared spectrometer (FTIR), thermal gravimetry (TG/DTG), X-ray diffractometry (XRD), and Raman spectroscopy. The BET data of the biochar increased by 125.3 times than that of the original biochar. The layer spacing and the surface functional groups of the pretreated biochar also increased. After performing the micro-morphological regulation of biomass using sodium hydroxide, the adsorption performance of biochar with regard to PAE effectively improved and an adsorption capacity of 125 mg/g was observed for DMP. The adsorption kinetics and thermodynamic experiments showed that DMP adsorption by biochar follows the Langmuir and pseudo-second-order models.

Efficient photocatalytic removal of phthalates easily implemented over a bi-functional {001}TiO2 surface

Purity assay of high-purity materials (HPMs) of phthalic acid esters (PAEs) was carried out by means of a mass balance method. In this method, chromatographic methods such as gas chromatography-flame ionization detector (GC-FID) and/or high-performance liquid chromatography (HPLC) in combination with other methods such as Karl-Fischer (KF) titration and vacuum evaporation (VE) were applied. The sum of the impurities estimated by these methods allowed the estimation of the purity of the main component by difference. Seven PAEs with varying side chain structures and levels of impurities were analysed on a systematic way in which impurities were classified into several groups in terms of their abundance, availability of qualitative information and availability of authentic compounds, etc. The absolute quantity of each impurity was determined by GC-FID and/or HPLC based on the calibration made by the authentic compounds of impurities whenever available. The purities in mass fraction of these PAEs were certified at the National Metrology Institute of Japan (NMIJ), and the PAEs were registered as primary reference materials playing an essential role in linking the metrological traceability of the Japan Calibration Service System (JCSS) to the International System of Units (SI).

Phthalic acid esters (PAEs) are a class of common environmental endocrine disruptors (EEDs), capable of causing considerable pollution to water, soil, and air and producing a range of adverse health impacts in humans. Although various studies have investigated the pollution characteristics and health hazards of PAEs in different media, a systematic review of PAEs in the broader environmental context is still lacking. In order to comprehensively explore current issues and suggest prospects, the current status, detection technology, toxicity, and health hazards of PAEs were investigated. The results suggest that PAE pollution is a widespread and complex global phenomenon, transported over long distances. The traditional techniques used for determination include high-performance liquid chromatography–mass spectrometry (HPLC-MS), gas chromatography–mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Various detection techniques offer distinct advantages and disadvantages. Moreover, PAEs can cause differing extents of harm to the nervous and reproductive systems of mammals. In the future, it is imperative to improve the detection of PAEs, establish rapid identification approaches, refine toxicological research methods, and investigate more comprehensive health risk assessment methods. These efforts will provide scientific support for the prevention and management of the resulting contaminants.