Di-n-octyl Phthalate Research Articles

Lipophilic phthalic acid esters impair human sperm acrosomal reaction through the likely inhibition of phospholipase A2-signaling pathway

Phthalic acid esters (PAEs) are recognized endocrine disruptors. Detection of PAEs in semen from idiopathic infertile males suggests possible direct mechanisms of sperm toxicity. In this study we aimed to correlate sperm function with semen levels of PAEs. Semen samples were obtained from 100 male patients attending the Unit of Andrology and Reproductive Medicine, University Hospital of Padova, (Italy), 22 of which having a recognized history of idiopathic infertility. Compared to fertile subjects, infertile patients showed reduced levels of acrosome reaction (AR), evaluated by CD46 staining upon progesterone (P4) triggering (p < 0.001). Subjects showing positive detection of PAEs in semen, evaluated by liquid chromatography-mass spectrometry (LC-MS), were significantly more represented in those reporting an history of infertility (13 out of 22), compared to fertile subjects (25 out of 78, P = 0.0266). In vitro sperm exposure to PAEs showed that lipophilic PAE representative Di-n-octyl phthalate (DNOP) had higher cell accumulation and inhibition of P4-induced AR than less lipophilic PAE representative Dibutyl phthalate (DBP). Computer-based binding analysis and fluorimetric inhibition assay, showed that both DNOP and DBP had similar Phospholipase-A2 (PLA2) inhibitory activity (respectively: 3.98 nM and 5.52 nM). However, only DNOP showed a significant inhibition of PLA2-mediated AR, triggered by A23187 calcium ionophore. Incubation with PLA2-related product arachidonic acid restored AR. Our data are suggestive of a novel mechanistic model of PAEs interference on sperm function, through the inhibition of PLA2-mediated signaling. According to this hypothesis, the inhibitory efficacy of the specific PAE is possibly linked to the corresponding cell accumulation.

Optimized LC-MS/MS method for simultaneous determination of endocrine disruptors and PAHs bound to PM2.5: Sources and health risk in Indo-Gangetic Plain

Airborne particulate matter (PM) is a serious health threat when it is bound to hazardous pollutants like phthalic acid esters (PAEs) (endocrine disruptors) and polycyclic aromatic hydrocarbons (PAHs). In this study, an optimized method was developed and validated for the simultaneous screening and quantification of PAEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), bis (2-ethyl hexyl) phthalate (DEHP), bis(2-ethylhexyl) adipate (DEHA), di-n-octyl phthalate (DNOP)) and PAHs (benzo[a]anthracene (B[a]A), benzo[b]fluorenthene (B[b]F), benzo[k]fluorenthene (B[k]F), benzo[a]pyrene (B[a]P), dibenzo[ah]anthracene (D[ah]A), benzo[ghi]perylene (B[ghi]P), and indeno[1,2,3-cd]pyrene (IND)) bound to ambient PM2.5 using liquid chromatography coupled to electrospray ionization tandem mass spectrometer (LC-ESI-MS/MS). The developed method exhibited excellent linearity (r2 > 0.99), precision error less than 10%, good recovery percentages (90%–120%, except for DMP ≈ 65%). After the validation, this method was deployed to investigate the seasonal variation and source identification of targeted compounds bound to ambient PM2.5 at a measurement site in the North West Indo-Gangetic Plain (NWIGP). In this study, the most abundant PAE and PAH are DEHP (17.94 ng m−3) and B[b]F (36.13 ng m−3), respectively. Measured concentrations of B[a]P, Group 1 carcinogen (4.66 ng m−3) had exceeded the National Ambient Air Quality Standards, India (1 ng m−3). Diagnostic ratios (DRs) revealed that fossil fuel/diesel combustions are the major emission sources of PAHs in summer and monsoon while biomass/coal combustions in winter season at the sampling site. Further, incremental lifetime cancer risk (ILCR) for adults and children due to exposure to PM2.5 bound DEHP (adults: 0.3678 × 10−6 and children: 0.8792 × 10−6) and B[a]Peq (adults: 1.40 × 10−5 and children: 3.272 × 10−5) were estimated. Estimated ILCR values for B[a]Peq exceeded the threshold value (1 × 10−6) set by USEPA. Findings in this study reveal that the health risk due to exposure to PAEs and PAHs bound to PM2.5 should be of concern.

Development of ecological risk assessment for Diisobutyl phthalate and di-n-octyl phthalate in surface water of China based on species sensitivity distribution model

Phthalic acid esters (PAEs) are commonly used as plasticizer and are emerging concern worldwide for potent adverse effects of aquatic organisms. Certain PAEs were often detected in different environmental matrices but related toxicity data were still lacking to support their risk assessment. The study investigated the acute toxicity of Diisobutyl phthalate (DiBP) and Di-n-octyl phthalate (DnOP) using 6 Chinese resident aquatic organisms from 3 phyla and 6 species and constructed the species sensitivity distribution (SSD) models for ecological risk assessment. Lethal concentration 50% (LC50) ranges of DiBP and DnOP were 4.89–21.45 mg/L and 1.45–1200 mg/L, respectively. The derived acute and chronic predicted no-effect concentrations (PNECs) based on log-normal model of water were 0.54 and 0.04 mg/L for DiBP and 0.23 and 0.05 mg/L for DnOP, respectively. The ERA for DiBP and DnOP in the surface water and sediment of China was conducted. Water samples of Haihe Rive (RQ = 0.41) and Hun River (RQ = 0.16) of DiBP showed medium risk. And sediment samples of Yellow River (RQ = 0.71) and Chao Hu Lake (RQ = 0.42) of DiBP showed medium risk. Meanwhile, the above water and sediment samples (RQ＜0.1) of DnOP showed low risk.

Occurrence and distribution of phthalate esters and microplastics in wastewater treatment plants in Taiwan and their toxicological risks

Phthalate esters (PAEs) are fat soluble synthetic chemicals, usually regarded as plasticizers for being added in numerous plastic products. Thus, environmental and health hazards of PAEs are associated with increasing plastic pollution. In this study, PAEs from sludge samples collected from water, sewage, and industrial treatment plants (N = 17) were analyzed using Gas Chromatography/Mass Spectrometry. Microplastics (MPs) were also quantified and correlated with PAEs. Results showed the highest average PAE concentrations in sewage treatment plants. The greatest ΣPAEs concentration were found in sewage treatment plant (STP4) with 32,414 μg/kg dw, while the lowest found in water treatment plant (WTP3) with 2062 μg/kg dw. Among different PAEs, di-(2-ethyl hexyl) phthalate (DEHP) contributes the highest. Similarly, DEHP, di-n-octyl phthalate (DnOP) and diisononyl phthalate (DiNP) significantly correlated with the total PAEs indicating their large contribution to sludge contamination. The abundance of microplastics in sludge ranged between 1 and 7 MP/g, highest at ITP6, but not detected in some stations. While microplastics may potentially increase PAEs, there was no significant relationship between ΣPAEs and MP abundance. The estimated human daily intake of DEHP and di-n-butyl phthalate (DnBP) when contaminated sludge be used showed low toxicological risks to exposed adults. This research presents the sludge characteristics, PAEs, and microplastic concentrations in different wastewater treatment plants in Taiwan. PAE contamination was highly contributed by domestic and industrial wastes shown by their significant amounts in STP and ITP. Results further provide evidence for potential sludge recycling (WTP sludge) and application to soil.

Determination and Risk Associated with Phthalic Esters Distribution from the Ekpan River, Effurun, Delta State, Nigeria

Phthalates are additives or plasticizers added to make plastics soft. However, they could leach into the environment and cause harm to human health when contacted. Sites along the Ekpan river have been used for open dumping of refuse. The river also serves as a point source for the disposal of effluents from the Warri Refinery and Petrochemical Company Limited (WRPC). Hence, the need for a preliminary study of phthalates across the river system. Surface water samples were collected from six points along the Ekpan river. Phthalates were extracted using USEPA standard method 3535 and EPA method 8061. Gas Chromatography-Mass Spectrometer (GC-MS) was used for the analysis of six PAEs including di-n-butyl phthalate (DnBP or DPX), butyl benzyl phthalate (BBP), di(2-Ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (D-n-OP)), Dimethyl phthalate (DMP), and Diethyl phthalate (DEP) in the river system. Analysis of phthalates in the Ekpan river system showed that DEP across the Effurun river system ranged from 4.22 – 13.81 μg/L, DPX; 3.03 – 11.5 μg/L, BBP; 0.11–1.39 μg/L, DEHP; 0.12 – 3.33 μg/L. D-n-OP and DMP were below the limit of detection of the analytical instrument used (0.1 μg/L). The distribution of PAEs along the network of the river revealed that the sampling sites in the urban region were more contaminated with PAEs due to urbanization and an increase in population across the river network. Human health risk assessment revealed that the hazard quotient (HQ) for DEP, DPX, DEHP, and D-i-NP were below 1, indicating an acceptable risk of PAEs via ingestion or bathing of the river water. In addition, the Hazard Index (HI) via ingestion and bathing of the river water was less than 1 indicating acceptable risks. According to this study, these PAEs congeners are safe for toddlers, adolescents, and adults to eat and bathe in tap water. Even DEHP, the only PAEs congener designated as a carcinogenic agent by WHO, was shown to have a tolerable cancer risk. These findings indicate that there is no harm to children, adolescents, and adults from DEHP in the river water studied.

Analysis of the performance of the efficient di-(2-ethylhexyl) phthalate-degrading bacterium Rhodococcus pyridinovorans DNHP-S2 and associated catabolic pathways

The widespread use of plastic has led to the global occurrence of phthalate esters (PAEs) pollution. PAEs can be effectively removed from polluted environments by microbe-mediated degradation. Di-(2-ethylhexyl) phthalate (DEHP) has the highest residual concentration in agricultural soil-contaminated areas compared to other PAEs in most of China. The Rhodococcus pyridinovorans DNHP-S2 microbial isolate identified was found to efficiently degrade DEHP. Within a 72 h period, the bacteria were able to degrade 52.47% and 99.75% of 500 mg L−1 DEHP at 10 °C and 35 °C, respectively. Dimethyl phthalate (DMP) was first identified as an intermediate metabolite of DEHP, which is different from the previously reported DEHP catabolic pathway. Genomic sequencing of DNHP-S2 identified benzoate 1,2-dioxygenase and catechol 2,3/1,2-dioxygenase as potential mediators of DEHP degradation, consistent with the existence of two downstream metabolic pathways governing DEHP degradation. Three targets DEHP metabolism-related enzymes were found to be DEHP-inducible at the mRNA level, and DNHP-S2 was able to mediate the complete degradation of DEHP at lower temperatures, as confirmed via RT-qPCR. DNHP-S2 was also found to readily break down other PAEs including DMP, di-n-butyl phthalate (DBP), di-n-octyl phthalate (DnOP), and n-butyl benzyl phthalate (BBP). Together, these results thus highlight DNHP-S2 as a bacterial strain with great promise as a tool for the remediation of PAE pollution. In addition to providing new germplasm and genetic resources for use in the context of PAE degradation, these results also offer new insight into the potential mechanisms whereby PAEs undergo catabolic degradation, making them well-suited for use in PAE-contaminated environments.

Urinary concentration of endocrine-disrupting phthalates and breast cancer risk in Indian women: A case-control study with a focus on mutations in phthalate-responsive genes

BackgroundPhthalates are known endocrine-disrupting chemicals used indiscriminately as constituents in consumer products including food processing, and packaging, cosmetics, personal care and household items. Although, few studies have assessed the risk of breast cancer on exposure to phthalates, their association with breast cancer risk in Indian women have not yet been evaluated. MethodsWe conducted a case-control study involving 171 participants. Urinary concentrations of six phthalate dieters; DMP (Dimethyl phthalate), DEP (Diethyl phthalate), DBP (Dibutyl phthalate), BBP (benzyl butyl phthalate), DEHP (Di-2-ethyl-hexyl phthalate), DINOP (Di-n-octyl phthalate) were estimated by GC-MS and geometric means were calculated. Univariate and multivariable logistic regression was performed to assess breast cancer risk on exposure to phthalates. Genes responsive to phthalates were identified through literature search and matched with NGS data, and gene-enrichment analysis was performed. ResultsSignificant associations were observed between urinary phthalate concentrations and increased risk of breast cancer for di-butyl phthalate (OR=1.5, 95% CI; 1.06, 2.11, p = 0.002) and di-2-ethyl-hexyl phthalate (>median vs ≤ median; OR=2.97, 95% CI; 1.18, 7.47, p = 0.005) in multivariable analyses. We also found several phthalate-responsive gene mutations in paired breast tumor tissues, which include PTPRD (76.19%), AR (42.86%), CYP1A1 (42.86%), CYP19A1 (23.81%), AHRR (19.05%), PIK3CA (19.05%), CYP1B1 (9.52%), RB1 (9.52%) and MMP9 (9.52%). Gene-enrichment analysis revealed that these genes form a major part of ER/PR, PPAR and HIF-1α-TGF-β signaling cascades involved in breast cancer ConclusionAlthough the sample size is small, in this first case-control study from India, DBP and DEHP were found to be associated with increased risk of invasive breast cancer and tumor tissues revealed mutations in several phthalate-responsive genes. It is, therefore suggested that human biomonitoring in India and larger studies evaluating the early life genetic and epigenetic alterations on phthalates exposure are required to establish their role in breast carcinogenesis.

Occurrence and health risk assessment of phthalate esters in tobacco and soils in tobacco-producing areas of Guizhou province, southwest China

Flue-cured tobacco is one of the important sources of national economy in China. However, Phthalic acid esters (PAEs) are ubiquitous contaminants in the cultivation and growth management of flue-cured tobacco, and attracting more and more attention. Here, six priority PAEs were detected in tobacco and soils and their residue characteristics, pollution sources were analyzed, and their exposure risks to the health of farmers were assessed. The concentration of six total PAEs ranged from 0.78 to 4.79 mg/kg in tobacco with the average of 1.75 mg/kg, and 0.84–25.68 mg/kg in soils with the average of 5.40 mg/kg. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) had the highest detection frequency (DF = 100%) both in soil and tobacco samples. DEHP was the most abundant of the total PAEs in soil and tobacco samples, with the mean contribution values of 71.0% and 58.8%, respectively. Principal component analysis (PCA) indicates that the major sources of PAEs in the tobacco-soil system were plastic films, fertilizers and pesticides. Health risk assessment suggests that the non-cancer hazard indexes (NCHI) of dimethyl phthalate (DMP), diethyl phthalate (DEP), DBP and di-n-octyl phthalate (DnOP) in all samples for farmers were at acceptable levels (NCHI < 1), and the average carcinogenic hazard indexes (CHI) of butyl benzyl phthalate (BBP) and DEHP for farmers were 3.79 × 10−13 and 8.54 × 10−11 in soils, respectively, 8.23 × 10−13 and 1.95 × 10−11 in tobacco, respectively, which were considered to be very low level (CHI < 10−6). This study provides data on PAEs in tobacco and soils and their health risks which may provide valuable information to aid the management of tobacco cultivation and risk avoidance.

Exposure to phthalates in the sleeping microenvironment of university dormitories: A preliminary estimate based on skin wipe and dust sampling

Since synthetic materials that might contain phthalates are widely used to fabricate bedding and decorating materials, phthalates are typical pollutants in sleeping microenvironments. Although people spend more than 30% of time sleeping, exposure to phthalates in sleeping microenvironments has not been well characterized. In this study, we measured the occurrence of six commonly-used phthalates (dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBzP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DOP)) from skin wipes and settled dust in the sleeping microenvironment of university dormitories. Targeted phthalates were frequently detected (more than 80%) except for DEP (30%–58% and 70% for dermal and dust samples, respectively); and DnBP and DEHP predominated in all samples. Accumulated phthalates on skin surfaces were at similar levels on bare body parts (i.e., hands vs. forearms) during sleeping time. Phthalates in settled dust were significantly correlated with those detected from skin wipes. The estimated average daily intakes of studied phthalates (via inhalation and dermal absorption) ranged from 0.24 μg/kg/day to 1.12 μg/kg/day in the sleeping microenvironment of university dormitories (with the highest doses for DMP and DnBP). Exposure via dermal pathway contributed 38% and 64%, respectively for DMP and DEP, and over 80% for other phthalates during sleeping time. This study provides better understanding of phthalate transport, exposure, and associated control strategies in sleeping microenvironments.

Determination of phthalate acid esters (PAEs) in bottled water distributed in tehran: a health risk assessment study

ABSTRACT In this study, the levels of six PAEs [bis (2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP) and di-n-octyl phthalate (DNOP)] were determined from four types of bottled water)non-carbonated, mineral, carbonated and carbonated flavoured) using MSPE method (magnetic solid phase extraction) and GC/MS technique (gas chromatography/mass spectrometry). The mean concentration of total PAEs was 6.11 ± 1.43 µg/L. The mean concentration of DEHP was 2.22 ± 0.76 µg/L and was lower than the United States Environmental Protection Agency (USEPA) standard level in drinking water (6 μg/L for DEHP). The highest mean level of total PAE was observed in carbonated water (7.43 ± 2.03 μg/L) and the lowest mean level of total PAE was observed in non-carbonated water (5.15 ± 0.41 μg/L). The Monte Carlo method was applied to calculate the Target Hazard Quotient (THQ), Chronic Daily Intake (CDI), and Incremental Life Cancer Risk (ILCR) indexes. In all samples, the rank order of the estimated THQ values based on the 95% percentile was DEHP (4.77E-4) > DBP (2.25E-5) > BBP (1.99E-5) > DEP (2.75E-6) and there would be unlikely non-carcinogenic risks for consumers (THQ<1). The incremental lifetime cancer risk assessment revealed that phthalate esters (DEHP) in evaluated bottled water samples did not pose a serious concern to humans.

Photodegradation of phthalic acid esters under simulated sunlight: Mechanism, kinetics, and toxicity change

The photodegradation of two phthalic acid esters (PAEs), dimethyl phthalate (DMP) and di-n-octyl phthalate (DOP), under simulated sunlight in aqueous or organic phases (n-hexane (HEX) and dichloromethane (DCM)) was investigated. The mean photodegradation rates were ranked by half-lives as follows: DOP in DCM (3.77 h) < DMP in DCM (9.62 h) < DOP in H2O (3.99 days) < DMP in H2O (19.2 days) < DOP in HEX (21.0 days) < DMP in HEX (>30 days). Compound-specific stable isotope analysis (CSIA) combined with intermediate analysis was employed to explore the involved initial photoreaction mechanism. C–O bond cleavage, chlorine radical adduction to the aromatic ring, competing reactions of chlorine radical adduction to the aromatic ring and side chain, and a singlet oxygen-mediated pathway were mainly responsible for initial photodegradation mechanism of PAEs in H2O, DMP in DCM, DOP in DCM, and DOP in HEX, respectively. Furthermore, distinct isotope fractionation patterns of PAEs photodegradation open the possibility of using CSIA to differentiate the involved solvents in the field. More toxic and recalcitrant intermediates emerged during the photodegradation of DMP in DCM, while the risk to human health was reduced during the photochemical transformation of DOP in organic solvents.

Occurrence, sources, and risk assessments of phthalic acid esters in tea plantations in China

Phthalic acid esters (PAEs) are one of the most researched and controversial chemicals in recent years due to their widespread distribution in various environmental mediums. However, the status and environmental risks of PAEs in tea plantation soils remain unclear. In this study, the occurrence, sources, and potential risks of dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-octyl phthalate (DOP), and di-(2-ethylhexyl) phthalate (DEHP) in 38 tea plantation soils in China were investigated. Results showed that the total concentration of ∑PAEs ranged from 0.002 mg kg−1 to 10.90 mg kg−1, with a mean concentration of 1.04 mg kg−1. DEHP (range: ND–9.34 mg kg−1, mean: 0.91 mg kg−1) was the major congener in tea plantation soils, followed by DiBP (range: ND–1.56 mg kg−1, mean: 0.12 mg kg−1). The highest ∑PAEs content in tea plantation soil was observed in Shandong Province, Eastern China. The potential sources of PAEs in tea plantation soils were believed to be plastic films and fertilizers. The non-cancer risk of PAEs was acceptable (< 1). However, the DEHP in 68.42% soil samples posed potential cancer risks (> 10−6) to humans through the dietary route. The DiBP in 10.53% soil samples and DEHP in 5.26% soil samples may cause ecological risks (> 1) to the ecosystem. Thus, long-term continuous agricultural inputs could increase the DEHP and DiBP residues in tea plantation soils, thereby posing potential health risks and ecological risks. Effective measures must be taken to cut off possible sources of DEHP and DiBP in tea plantation soils or reduce their spread from soil to tea plants or food crops.

Determinants of phthalate exposures in pregnant women in New York City

Previous studies have provided data on determinants of phthalates in pregnant women, but results were disparate across regions. We aimed to identify the food groups and demographic factors that predict phthalate exposure in an urban contemporary pregnancy cohort in the US. The study included 450 pregnant women from the New York University Children's Health and Environment Study in New York City. Urinary concentrations of 22 phthalate metabolites, including metabolites of di-2-ethylhexylphthalate (DEHP), were determined at three time points across pregnancy by liquid chromatography coupled with tandem mass spectrometry. The Diet History Questionnaire II was completed by pregnant women at mid-pregnancy to assess dietary information. Linear mixed models were fitted to examine determinants of urinary phthalate metabolite concentrations. Using partial-linear single-index (PLSI) models, we assessed the major contributors, among ten food groups, to phthalate exposure. Metabolites of DEHP and its ortho-phthalate replacement, diisononyl phthalate (DiNP), were found in >90% of the samples. The sum of creatinine-adjusted DiNP metabolite concentrations was higher in older and single women and in samples collected in summer. Hispanic and non-Hispanic Black women had lower urinary concentrations of summed metabolites of di-n-octyl phthalate (DnOP), but higher concentrations of low molecular weight phthalates compared with non-Hispanic White women. Each doubling of grain products consumed was associated with a 20.9% increase in ∑DiNP concentrations (95%CI: 4.5, 39.9). PLSI models revealed that intake of dried beans and peas was the main dietary factor contributing to urinary ∑DEHP, ∑DiNP, and ∑DnOP levels, with contribution proportions of 76.3%, 35.8%, and 27.4%, respectively. Urinary metabolite levels of phthalates in pregnant women in NYC varied by age, marital status, seasonality, race/ethnicity, and diet. These results lend insight into the major determinants of phthalates levels, and may be used to identify exposure sources and guide interventions to reduce exposures in susceptible populations.

Evaluation of occurrence, fate and removal of priority phthalate esters (PAEs) in wastewater and sewage sludge by advanced biological treatment, waste stabilization pond and constructed wetland

Phthalate Esters (PAEs), detected in high concentrations generally in treated wastewater discharged from wastewater treatment plants (WWTPs), are important pollutants that restrict the reuse of wastewater. Investigating the fate of these endocrine-disrupting chemicals in WWTPs is crucial in order to protect both receiving environments and ecosystems. For this purpose, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP) and benzyl butyl phthalate (BBP) in the group of PAEs were monitored in simultaneously both in wastewater and sludge lines of selected two nature-based WWTPs and one advanced biological WWTP.Although it was frequently stated that phthalates were significantly removed in WWTPs in many studies found in literature, negative removal efficiencies of selected phthalates in investigated WWTPs during the sampling period were observed generally in this study. One of the reasons for this concentration increase could be releasing of phthalates from microplastics in wastewater during the treatment process or the desorption of PAEs from treatment sludge. DNOP was the compound with the highest concentration increase at almost each treatment unit of the three WWTPs. On the other hand, total PAEs load was 1997 g d−1 in advanced biological WWTP and adsorption onto sludge of PAEs were determined as 90%. The side-stream total load returned from the decanter supernatant was 0.02% of the total PAEs load coming to advanced biological WWTP from the sewer system.As a result of detailed statistical analysis, the correlation between raw wastewater and primary clarifier (PC) effluent was determined as an increasing linear relation for DEHP and DNOP. On the other hand, moderate and strong correlations were observed both between septic tank and constructed wetland (CW) processes with raw wastewater. In the waste stabilization pond (WSP), while a significant correlation was not found between the sludge line data, homogeneous variance, strong and moderate correlations were obtained in the wastewater line data. However, while mean differences for all investigated PAEs were not significant (p > 0.05) in the wastewater line, mean differences of DEHP (p < 0.05) were significant in the sludge line according to ANOVA analysis.

Phthalate's multiple hormonal effects and their supplementary dietary regulation scheme of health risks for children.

Four common phthalic acid esters (PAEs), namely, butylbenzyl phthalate (BBzP), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DNOP) that are known to affect children upon exposure, were selected, and the hormone effects were explored during different supplementary food intakes by using methods such as factorial design experiment, molecular docking, and dynamics simulation techniques. A supplementary diet regulation scheme to prevent health risks of PAEs was constructed to avoid or mitigate the hormonal effects in children exposed to PAEs. Firstly, the MM/PBSA binding energy of PAEs with single hormone receptors and multiple hormone receptor complexes was calculated. In addition, 10 foods were selected as external interference conditions to carry out dynamic simulation, which showed that kiwi fruit and broccoli can effectively alleviate the PAEs' hormone effects. Furthermore, inference of the metabolic process of DEHP found that the supplementary diets could effectively promote the metabolism of PAEs. Finally, based on the mechanism analysis, it was confirmed that the selected supplementary diets could inhibit the binding process. This study aims to explore the role of supplementary diets in regulating various PAEs' hormone effects and thereby provide theoretical support for slowing down hormonal effects in children.

Preparation of ECTFE Porous Membrane for Dehumidification of Gaseous Streams through Membrane Condenser.

Due to the good hydrophobicity and chemical resistance of poly(ethylene trifluoroethylene) (ECTFE), it has been an attractive potential material for microfiltration, membrane distillation and more. However, few porous hydrophobic ECTFE membranes were prepared by thermally induced phase separation (TIPS) for membrane condenser applications. In this work, the diluent, di-n-octyl phthalate (DnOP), was selected to prepare the dope solutions. The calculated Hassen solubility parameter indicated that ECTFE has good compatibility with DnOP. The corresponding thermodynamic phase diagram was established, and it has been mutually verified with the bi-continuous structure observed in the SEM images. At 30 wt% ECTFE, the surface contact angle and liquid entry pressure reach their maximum values of 139.5° and 0.71 MPa, respectively. In addition, some other basic membrane properties, such as pore size, porosity, and mechanical properties, were determined. Finally, the prepared ECTFE membranes were tested using a homemade membrane condenser setup. When the polymer content is 30 wt%, the corresponding results are better; the water recovery and condensed water yield is 17.6% and 1.86 kg m−2 h−1, respectively.

Dynamic variations of phthalate esters in PM2.5 during a pollution episode

Phthalate esters (PAEs) as hazardous air pollutants can be easily released during the life cycle of plastic products. In this study, a thermal desorption aerosol comprehensive two-dimensional gas chromatography mass spectrometer coupled with a dual-trap was developed and used to measure the hourly-resolved PAEs characteristics in atmospheric PM2.5 at an urban site. Dimethyl phthalate (DMP), diethyl (DEP), dibutyl (DnBP), benzyl butyl (BBP), di(2-ethylhexyl) (DEHP), and di-n-octyl phthalate (DnOP) in PM2.5 were analyzed. The most abundant compounds were DEHP and DMP, followed by DnBP and DEP. The mass concentrations of the detected PAEs are comparable to those at other urban sites measured using offline methods with a lower time resolution. The concentrations of PAEs showed intense change with the variation of PM2.5 mass concentration. The proportion of DEHP increased while that of DMP decreased with the increase in PM2.5 pollution. Positive correlations between PAEs and PM2.5, organic carbon, and elemental carbon were observed, while PAEs had negative correlation with the ambient temperature. Our observation provides evidences on understanding the volatile and semi-volatile PAEs in the ambient aerosols.

Removal of Emerging Pollutants in Horizontal Subsurface Flow and Vertical Flow Pilot-Scale Constructed Wetlands

We assessed constructed wetland (CW) performance in the removal of six emerging pollutants (EPs) from university campus wastewater. The EPs considered were: diethyl phthalate (DEP), di-isobutyl phthalate (DIBP), di-n-octyl phthalate (DNOP), bis(2-ehtylxexyl) phthalate (DEHP), tris(1-chloro-2-propyl) phosphate (TCPP) and caffeine (CAF). Six pilot-scale CWs, i.e., three horizontal subsurface flow (HSF) and three vertical flow (VF), with different design configurations were used: two types of plants and one unplanted for both the HSF and the VF, two hydraulic retention times (HRT) for the HSF, and two wastewater feeding strategies for the VF units. The results showed that the median removals in the three HSF-CWs ranged between 84.3 and 99.9%, 79.0 and 95.7%, 91.4 and 99.7%, 72.2 and 81.0%, 99.1 and 99.6%, and 99.3 and 99.6% for DEP, DIBP, DNOP, DEHP, TCPP, and CAF, respectively. In the three VF-CWs, the median removal efficiencies range was 98.6–99.4%, 63.6–98.0%, 96.6–97.8%, 73.6–94.5%, 99.3–99.5% and 94.4–96.3% for DEP, DIBP, DNOP, DEHP, TCPP and CAF, respectively. The study indicates that biodegradation and adsorption onto substrate were the most prevalent removal routes of the target EPs in CWs.

Evaluation of the Removal of Selected Phthalic Acid Esters (PAEs) in Municipal Wastewater Treatment Plants Supported by Constructed Wetlands.

Phthalic acid esters (PAEs) have a negative impact on living organisms in the environment, therefore, are among the group of Endocrine Disrupting Compounds (ECDs). Unfortunately, conventional methods used in municipal wastewater treatment plants (MWWTPs) are not designed to eliminate PAEs. For this reason, the development of cheap and simple but very effective techniques for the removal of such residues from wastewater is crucial. The main aim of this study was the evaluation of the removal of six selected PAEs: diethyl phthalate (DEP), di-n-octyl phthalate (DOP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), bis(2-ethylhexyl) phthalate (DEHP) and dimethyl phthalate (DMP), in real MWWTPs supported by constructed wetlands (MWWTP–CW system). For the first time, the possibility of using three new plants for this purpose, Cyperus papyrus (papyrus), Lysimachia nemorum (yellow pimpernel) and Euonymus europaeus (European spindle), has been presented. For determining the target PAEs in wastewater samples, a method of SPE (Solid-Phase Extraction)–GC–MS(SIM) was developed and validated, and for plant materials, a method of UAE (Ultrasound-Assisted Extraction)–SPE–GC–MS(SIM) was proposed. The obtained data showed that the application of the MWWTP–CW system allows a significant increase in the removal of DEP, DBP, BBP and DEHP from the wastewater stream. Euonymus europaeus was the most effective among the tested plant species for the uptake of analytes (8938 ng × g−1 dry weight), thus, this plant was found to be optimal for supporting conventional MWWTPs.

Chamber study on the migration of di-n-octyl phthalate (DNOP) between source surfaces and settled dust: Influence of temperature and dust loading

Phthalates (PAEs) are pervasive in indoor environments. In this study, two migration pathways of di-n-octyl phthalate (DNOP) from a source to dust were investigated using microchambers in a thermostatic incubator: (1) mass transfer through direct contact with source surfaces; (2) mass transfer through air. A 20-day emission experiment with settled dust was performed at 30 °C. Significantly higher concentrations were observed in dust that was in direct contact than in dust that was not, which indicated that direct contact enhanced the sorption of the dust on DNOP. The difference between source and non-source surface was low of the migration of the DNOP in the dust. In addition, the temperature and dust loading and diffusion distance were considered. The results suggested that the temperature did not considerably influence the difference between source and non-source surface; however, the difference increased with an increase in dust loading. These results can help understand the mass transfer mechanism of PAEs to implement effective control measures and reduce the human exposure to PAEs in indoor environments.