Diethylhexyl Phthalate Research Articles

Effects of bone marrow-derived mesenchymal stem cells exposed to endocrine-disrupting chemicals on the differentiation of umbilical cord blood hematopoietic stem cells.

Endocrine-disrupting chemicals (EDCs), a class of peripheral toxic substances, can cause many environmental and clinical side effects, particularly on the human body's endocrine system. Bisphenol A (BPA) and diethylhexyl phthalate (DEHP) are two well-known EDCs in the medicine industry. However, there are no comprehensive studies on their effects on hematopoiesis. Hence, this study aimed to investigate the effect of these two aforementioned substances on the clonogenic capacity of umbilical cord blood hematopoietic stem cells (CB-HSCs). The HSCs which express CD34 + were isolated from umbilical cord blood by the magnetic-activated cell sorting (MACS) system. To investigate the effects of different optimized concentrations of BPA and DEHP, CB-CD34+ HSCs were exposed to EDCs in semisolid medium. For evaluation of coexposures, CB-CD34+ HSCs were cocultured with bone marrow-derived mesenchymal stem cells (BM-MSCs) in the presence of BPA and DEHP. Finally, the number and types of colonies were evaluated after 14days. Statistical analysis was performed by GraphPad Prism through ANOVA. CB-HSC treated by BPA and DEHP showed a lower absolute colony count than the control group (P < 0.05). Decrease in clonogenic potential of HSCs was more significant in coculture condition by MSCs. In particular, there was a significant decrease in the BFU-E colonies in comedicated-derived fractions (P < 0.0001). In the presence of EDCs such as BPA and DEHP, the patterns of differentiation in CD34+ CB-HSCs changed from suppressed erythroid differentiation toward stimulated myelogenesis pathways.

Environmental Pollution to Blame for Depressive Disorder?

Public concern has emerged about the effects of endocrine-disrupting compounds (EDCs) on neuropsychiatric disorders. Preclinical evidence suggests that exposure to EDCs is associated with the development of major depressive disorder (MDD) and could result in neural degeneration. The interaction of EDCs with hormonal receptors is the best-described mechanism of their biological activity. However, the dysregulation of the hypothalamic-pituitary-gonadal adrenal axis has been reported and linked to neurological disorders. At a worldwide level and in Mexico, the incidence of MDD has recently been increasing. Of note, in Mexico, there are no clinical associations on blood levels of EDCs and the incidence of the MDD. Methodology: Thus, we quantified for the first time the serum levels of parent compounds of two bisphenols and four phthalates in patients with MDD. The levels of di-ethyl-hexyl-phthalate (DEHP), butyl-benzyl-phthalate (BBP), di-n-butyl phthalate (DBP), and di-ethyl-phthalate (DEP), bisphenol A (BPA), and bisphenol S (BPS) in men and women with or without MDD were determined with a gas chromatograph-mass spectrometer. Results/conclusion: We found significant differences between concentrations of BBP between controls and patients with MDD. Interestingly, the serum levels of this compound have a dysmorphic behavior, being much higher in women (~500 ng/mL) than in men (≤10 ng/mL). We did not observe significant changes in the serum concentrations of the other phthalates or bisphenols tested, neither when comparing healthy and sick subjects nor when they were compared by gender. The results point out that BBP has a critical impact on the etiology of MDD disorder in Mexican patients, specifically in women.

Manipulation of cadmium and diethylhexyl phthalate on Rana chensinensis tadpoles affects the intestinal microbiota and fatty acid metabolism

Gastrointestinal tract and intestine microbiota can both have deep effects on the lipid metabolism and immune function of amphibians. Additionally, the composition and structure of the microbial community are influenced by environmental pollutions. It is noteworthy that environmental compounds such as Cd and DEHP are pervasive in the aquatic environment and do not exist in isolation, and single exposure experiments cannot well explain the effects of unpredictable interactions between co-existing compounds on amphibians. In this study, we calculated the parameters of morphological and histological indices of Rana chensinensis tadpoles after treated with Cd and/or DEHP. The 16S rRNA gene sequencing technology was used to assess the relative abundance of intestinal microbial community among tadpoles from each treatment groups. We also examined the mRNA expression levels of lipid digestion and absorption and SCFAs related-genes. Our results indicated that all morphological and histological indices were significantly declined in the Cd treatment group, while the mixed treatment group was similar to the control group. Compared with the control group, the relative abundances of Firmicutes, Proteobacteria and Verrucomicrobia exhibited distinctive differences in Cd and/or DEHP treatment groups. Further, RT-qPCR results revealed that the expression levels of lipid metabolism and SCFAs related-genes were also significantly altered among the treatment groups. Taken together, the present study highlighted a new evidence that the alterations in intestinal microbial community and mRNA expression levels of larval amphibians after exposure to Cd and/or DEHP may impair lipid storage and transport, as well as reduce anti-inflammatory capacity, which may ultimately lead to a decline in amphibian populations.

Impact of Contaminants on Microbiota: Linking the Gut-Brain Axis with Neurotoxicity.

Over the last years, research has focused on microbiota to establish a missing link between neuronal health and intestine imbalance. Many studies have considered microbiota as critical regulators of the gut–brain axis. The crosstalk between microbiota and the central nervous system is mainly explained through three different pathways: the neural, endocrine, and immune pathways, intricately interconnected with each other. In day-to-day life, human beings are exposed to a wide variety of contaminants that affect our intestinal microbiota and alter the bidirectional communication between the gut and brain, causing neuronal disorders. The interplay between xenobiotics, microbiota and neurotoxicity is still not fully explored, especially for susceptible populations such as pregnant women, neonates, and developing children. Precisely, early exposure to contaminants can trigger neurodevelopmental toxicity and long-term diseases. There is growing but limited research on the specific mechanisms of the microbiota–gut–brain axis (MGBA), making it challenging to understand the effect of environmental pollutants. In this review, we discuss the biological interplay between microbiota–gut–brain and analyse the role of endocrine-disrupting chemicals: Bisphenol A (BPA), Chlorpyrifos (CPF), Diethylhexyl phthalate (DEHP), and Per- and polyfluoroalkyl substances (PFAS) in MGBA perturbations and subsequent neurotoxicity. The complexity of the MGBA and the changing nature of the gut microbiota pose significant challenges for future research. However, emerging in-silico models able to analyse and interpret meta-omics data are a promising option for understanding the processes in this axis and can help prevent neurotoxicity.

Impacts of diethylhexyl phthalate and overfeeding on physical fitness and lipid mobilization in Danio rerio (zebrafish)

As the prevalence of obesity has steadily increased on a global scale, research has shifted to explore potential contributors to this pandemic beyond overeating and lack of exercise. Environmental chemical contaminants, known as obesogens, alter metabolic processes and exacerbate the obese phenotype. Diethylhexyl phthalate (DEHP) is a common chemical plasticizer found in medical supplies, food packaging, and polyvinyl materials, and has been identified as a probable obesogen. This study investigated the hypothesis that co-exposure to DEHP and overfeeding would result in decreased lipid mobilization and physical fitness in Danio rerio (zebrafish). Four treatment groups were randomly assigned: Regular Fed (control, 10 mg/fish/day with 0 mg/kg DEHP), Overfed (20 mg/fish/day with 0 mg/kg DEHP), Regular Fed + DEHP (10 mg/fish/day with 3 mg/kg DEHP), Overfed + DEHP (20 mg/fish/day with 3 mg/kg DEHP). After 24 weeks, swim tunnel assays were conducted on half of the zebrafish from each treatment to measure critical swimming speeds (Ucrit); the other fish were euthanized without swimming. Body mass index (BMI) was measured, and tissues were collected for blood lipid characterization and gene expression analyses. Co-exposure to DEHP and overfeeding decreased swim performance as measured by Ucrit. While no differences in blood lipids were observed with DEHP exposure, differential expression of genes related to lipid metabolism and utilization in the gastrointestinal and liver tissue suggests alterations in metabolism and lipid packaging, which may impact utilization and ability to mobilize lipid reserves during physical activity following chronic exposures.

Gone with the flow - Assessment of personal care products in Portuguese rivers

Although there are several works in the literature that study the presence of pharmaceuticals and personal care products (PPCPs) in surface waters, the vast majority focus their attention on pharmaceuticals and little information is found about personal care products (PCPs). Therefore, this study focused, for the first time, on the monitoring of five classes of PCPs – fragrance allergens, synthetic musks, phthalates, antioxidants, and ultraviolet-filters - in the surface water of four small-size typically pollution-impacted Portuguese rivers (Ave, Leça, Antuã and Cértima). A solid-phase microextraction (SPME) followed by gas chromatography - tandem mass spectrometry (GC-MS/MS) protocol was employed to analyse surface water samples collected in two seasonal campaigns - summer and winter (34 samples per season). A total of 22 out of 37 target PCPs were detected concomitantly at least once in one sampling point, being the most frequently detected α-isomethyl ionone, galaxolide, tonalide and cashmeran. The highest concentrations were confirmed for diethylhexyl phthalate (610.6 ng L−1), galaxolide (379.2 ng L−1), geraniol (290.9 ng L−1), linalool (271.2 ng L−1), benzophenone-3 (254.1 ng L−1) and citronellol (200.2 ng L−1). Leça River, traversing the more densely urban and industrialized area, had the highest levels of contaminants, which were also found in the sampling points located downstream of wastewater treatment plants discharge points. In general, higher levels were detected in summer, when the river flows are lower. Hazard quotients were determined and octocrylene, tonalide, and geraniol presented values above 1 in some sampling sites, which may indicate an ecotoxicological risk to the aquatic environment. The results presented suggest that these three PCPs should be included as priority pollutants in environmental monitoring schemes in surface waters, due to their high detection, persistence, and potential adverse effects.

Role of Hepatocyte- and Macrophage-Specific PPARγ in Hepatotoxicity Induced by Diethylhexyl Phthalate in Mice

Background:Phthalates may disturb metabolic homeostasis in the liver by interfering with the peroxisome proliferator-activated receptors (PPARs). However, the role of hepatic macrophages in the lipid metabolic dysregulation induced by diethylhexyl phthalate (DEHP) remains unclear.Objectives:We aimed to evaluate the respective role of hepatocyte- and macrophage-specific in the hepatotoxicity induced by DEHP.Methods:Wild-type (WT), hepatocyte-specific knockout (Hep-KO), and macrophage-specific PPAR knockout (Mac-KO) mice were administered DEHP ( body weight) by daily gavage for 28 d, followed by hepatotoxicity examination and macrophage analysis. RNA sequencing and lipid metabolomic analysis were used to characterize the molecular changes in mouse liver. Mouse bone marrow-derived macrophages (BMDMs) and human monocytic THP-1 cell-derived macrophages were used to investigate the mechanistic regulation of macrophages’ polarization by DEHP and mono(2-ethylhexyl) phthalate (MEHP).Results:The levels of hepatic steatosis and triglyceride were significantly higher in the mice treated with DEHP compared with the control mice in the WT and Hep-KO model. Lipid accumulation induced by DEHP was notably attenuated in the Mac-KO mice, but M2-polarization of hepatic macrophages in the Mac-KO mice was significantly higher compared with the WT mice under DEHP treatment. The M2-polarization of BMDMs and human macrophages was suppressed by DEHP and MEHP. Transcriptomic and lipidomic data suggested lower levels of lipid biosynthesis, fatty acid oxidation, and oxidative phosphorylation in the Mac-KO mice compared with the WT and Hep-KO mice under DEHP treatment.Conclusions:Our data suggested that the orchestrated activation of and by MEHP may reprogram hepatic macrophages’ polarization, thereby affecting lipid homeostasis in the mouse liver. Although this conclusion was based on studies conducted in mice and in vitro, these findings may aid in elucidating the health effect of environmental phthalate exposure. https://doi.org/10.1289/EHP9373

The Role of Di(2-Ethylhexyl) Phthalate as an Exacerbating Factor in Chronic Spontaneous Urticaria.

Phthalates are one of the most commonly used endocrine disruptors and have been considered a risk factor for respiratory disease including asthma. However, it is not yet known how they are related to urticaria. We investigated the association between phthalate exposure and urticaria in 10 healthy controls and 20 adult patients with active urticaria. The urinary levels of mono-n-butyl phthalate (MnBP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP), mono-(2-ethyl-5-oxohexyl) phthalate, and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) were measured by using high performance liquid chromatography tandem mass spectrometry, and mast cell releasability was determined after phthalate treatment. The levels of phthalate metabolites, especially di-ethylhexyl phthalate (DEHP), are significantly increased in the urine of patients with urticaria compared to the healthy controls. The release of β-hexosaminidase in human mast cells is more significantly increased by MnBP, mono-benzyl phthalate, MEHHP, and MECPP compared to the negative controls; interestingly, the highest secretion of β-hexosaminidase is observed after the lowest stimulation of MECPP. Phthalates, including DEHP, may act as aggravating factors for chronic spontaneous urticaria and can be used as potential therapeutic targets in future studies.

Investigation of Diethyl Hexyl Phthalate Migration from Poly(Vinyl Chloride) Serum Bags

Plasticizers are used to make Poly (Vinyl Chloride) (PVC) flexible so it can be used in different areas such as intravenous solution containers. Plasticizers can migrate from PVC over time because of contact with these solutions; this phenomenon creates gaps in the polymer structure and causes the migration of other additives. This paper discusses the specific migration of di-2-ethyl hexyl phthalate (DEHP) from plasticized poly (vinyl chloride) (PVC) into 5% glucose solution, although studying the possibility of migration of other components. For this purpose, the bags were stored in real conditions by respecting temperatures (20 ± 2°C) and time of conservation (18 months). Samples were taken off every 3 months to be analyzed. The Fourier transform infrared spectroscopy was used to investigate the migration phenomena, the atomic absorption spectrometry was used to follow the migration's evolution of metals from plastic bags and the gas chromatography coupled with mass spectrometry was used for the determination of DEHP migration. The results obtained by the three techniques showed the migration of the serum bags additives such as DEHP in the glucose solution. This migration depends on time of contact.

Environmental fate of dibutylphthalate in agricultural plastics: Photodegradation, migration and ecotoxicological impact on soil

Phthalic acid esters (PAEs) were determined in polyethylene covers used in horticultural production units located at Moreno and La Plata districts (Buenos Aires, Argentina), detecting 0.69–8.75 mg PAEs kg−1 plastic in greenhouse and tunnel films. The PAEs found were diisobutylphthalate (DIBP), dibutylphthalate (DBP) and diethylhexylphthalate (DEHP). DBP was chosen as a model molecule to carry out the photochemical degradation studies that led to the formation of monobutylphthalate (MBP) and phthalic acid (PA).DBP, MBP and PA migration from plastic covers was studied, finding that while DBP and MBP moved to soil and atmosphere in short times (<48 h), PA remained in the agricultural covers. Further experiments with DBP were made to explore the effect on migration of temperature (20 °C, 50 °C), film thickness (25 μm, 100 μm) and plastic ageing by solarization, observing that temperature increase, film thickness reduction and ageing by solarization favored DBP migration to the environment.DBP and MBP impact on soil were evaluated by avoidance and reproduction tests using Eisenia andrei as bioindicator. Both compounds reduced cocoon viability decreasing the number of juveniles at the lowest concentration assayed (0.1 mg kg−1 of soil). At higher DBP and MBP concentrations the reproductive parameters (number of total cocoons, hatchability and number of juveniles) also showed alterations compared with the controls. Carboxylesterases (CaE), cholinesterases (ChE) and glutathion-S-transferases (GST) activities were analyzed in E. andrei exposed to DBP; cholinesterases activities were reduced at 1 and 10 mg DBP kg−1 soil, and glutathione S-transferases activities were increased at 10 mg DBP kg−1 soil while no effect was observed on carboxylesterases activities.These results emphasize the need to continue studying the impact of PAEs and their photodegradation products on the environment.

Endocrine-disrupting chemicals used as common plastic additives: Levels, profiles, and human dietary exposure from the Indian food basket

Endocrine-disrupting chemicals (EDCs) such as phthalic acid esters (PAEs) and bisphenol A (BPA) are the most widely used plastic additives in polymeric materials. These EDCs are ubiquitously distributed in the environment. Hence selected PAEs and BPA were investigated in twenty-five food types and drinking water (supply and packaged) from the metropolitan city, Delhi, and the peri-urban areas of a non-metropolitan city, Dehradun. Except cabbage and orange, the sum of thirteen PAEs (∑13PAEs) and BPA in all the other food types were significantly higher in Delhi over Dehradun (p < 0.01). Highest mean ∑13PAEs (665 ng/g) and BPA (73 ng/g) were observed in cottage cheese and potatoes, respectively followed by fish (PAEs - 477 ng/g, BPA - 16 ng/g). Supply water from the west zone of Delhi was found to contain the highest concentration of BPA (309 ng/L) and ∑13PAEs (5765 ng/L) with the dominance of diethyl phthalate (DEP). Based on the compositional profile and compound-wise principal component analysis, environmental contamination and food processing were attributed as significant sources of most priority PAEs in food samples. Di-ethyl hexyl phthalate (DEHP) was over 100-fold higher in the bottled water from local brands than composite bottled water samples. Packaging material was identified as a source for di-n-butyl phthalate (DnBP) in packaged food. This study observed the highest estimated daily dietary intake (EDI) in the high-fat-containing food products viz., cottage cheese, and fish from north Delhi. High bioaccumulation of BPA can be a possible reason for elevated EDI in vegetables and local fish of Delhi. Unlike Dehradun, EDI for ∑13PAEs and BPA was slightly higher for the non-vegetarian adult when compared to the vegetarian adult. DEHP and DnBP exhibited the highest estimated estrogenic potential for bottled water from local brands. Dietary exposure due to six priority PAEs contamination in food stuffs was two to four-fold higher in Delhi than Dehradun for adult man and woman.

MRNA expression and protein-protein interaction (PPI) network analysis of adrenal steroidogenesis in response to exposure to phthalates in rats

Phthalate esters such as di-butyl phthalate (DBP) and di-ethyl hexyl phthalate (DEHP) used in personal care and consumer products and medical devices have potential to affect human health. We studied the effect of DBP and DEHP on critical enzymes of glucocorticoid biosynthesis pathway in the adrenal gland and pro-inflammatory cytokines in the serum in male Wistar rats. DEHP and DBP treatment altered the mRNA expression of enzymes of glucocorticoid biosynthesis pathway accompanied by a reduction in glucocorticoid production and elevation in the level of glucocorticoid regulated pro-inflammatory cytokines indicating a cascading effect of phthalates. The analysis of PPI (protein – protein interaction) network involving Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) of enzymes through STRING database revealed that all the proteins have the maximum level of interaction with the selected number of proteins. The STRING database analysis together with in vivo data indicates the potential effects of phthalates on various targets of steroidogenesis pathway with a global biological impact.

Association of phthalate exposure with thyroid function during pregnancy.

The extent of thyroid disruptive effects of phthalates during pregnancy remains unclear. To investigate the association of maternal urinary phthalates with markers of the thyroid system during early pregnancy. Urinary concentrations of phthalate metabolites and serum concentrations of thyroid stimulating hormone (TSH), free and total thyroxine (FT4 and TT4) and free and total triiodothyronine (FT3 and TT3) were measured in pregnant women in early pregnancy in the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy study (2007-ongoing), a population-based prospective cohort. In the 1,996 included women, higher di-ethyl-hexyl phthalate (DEHP) metabolites were associated with a lower FT4 (β [SE] for the molar sum: -0.13 [0.06], P=0.03) and a higher TSH/FT4 ratio (0.003 [0.001], P=0.03). Higher concentrations of di-iso-nonyl phthalate (DINP) metabolites were associated with a lower TT4 (β [SE] for the molar sum: 0.93 [0.44], P=0.03) as well as with lower TT4/FT4 and TT4/TT3 ratios. Higher metabolites of both dibutyl and butyl-benzyl phthalate (DBP and BBzP) were associated with lower T4/T3 ratio (free and total) and higher FT4/TT4 and FT3/TT3 ratios. A higher diisononyl cyclohexane dicarboxylate (DINCH) metabolite concentration was associated with a higher TT3. These results translate results from experimental studies suggesting that exposure to phthalates may interfere with the thyroid system during pregnancy. This is also true for compounds that have been introduced to replace known disruptive phthalates. Further experimental studies should take into account the human evidence to better investigate the potential underlying mechanisms of thyroid disruption by phthalates.

Female Reproductive Health and Exposure to Phthalates and Bisphenol A: A Cross Sectional Study.

The xenoestrogenicity of some plasticisers (phthalates and bisphenol A) is documented in the literature and may pose a risk to female reproductive health. The aim of this study was to assess exposure to six phthalates. This was achieved by measuring their respective metabolites (mono-ethylphthalate (MEP); mono-n-butylphthalate (MnBP); mono-n-ottylphthalate (MnOP); and monobenzylphthalate (MBzP)), as well as the sum of two of the diethyl-hexyl phthalate metabolites-(∑DEHP) and bisphenol A (BPA) in a female population with infertility problems, and by conducting a correlation analysis between infertility factors, work activities, and lifestyle habits, in order to formulate a causal hypothesis. A cross-sectional epidemiological study was carried out and women under 43 years of age were recruited from an assisted reproduction technology (ART) center; the sample of 186 women was given a specific questionnaire and a spot urine sample was collected. Phthalate metabolites and urinary BPA were analyzed by HPLC/MS/MS. The results showed significantly higher mean values for MEP in women with recurrent pregnancy loss (RPL) (820.5 ± 1929.5 µg/g of creatinine) and idiopathic infertility (230.0 ± 794.2 µg/g of creatinine) than in women with other infertility factors (76.9 ± 171.8 µg/g of creatinine). Similarly, for MnOP levels, women with idiopathic infertility (2.95 ± 3.44 µg/g of creatinine) showed significantly higher values than women with the other infertility factors taken together (1.35 ± 2.05 µg/g of creatinine). Women with tubal factors of infertility, RPL, and endocrine dysfunctions show higher values of DEHP (p = 0.032). Considering occupations, women working in commerce showed more than twice as much urinary BPA levels (1.10 ± 0.48 µg/g of creatinine) compared to women working in other industries (0.45 ± 0.35 µg/g of creatinine). The presence of significantly higher values of certain phthalates, DEHP in particular, especially in women with RPL and idiopathic infertility, suggests a possible involvement of these compounds as competing factors in reproductive issues. The study of sources of exposure suggested that the working activity in trade, as a casher in particular, represents a major one for BPA (p = 0.015).

Degradation of dibutyl phthalate by Paenarthrobacter sp. Shss isolated from Saravan landfill, Hyrcanian Forests, Iran

Phthalic acid esters are predominantly used as plasticizers and are industrially produced on the million ton scale per year. They exhibit endocrine-disrupting, carcinogenic, teratogenic, and mutagenic effects on wildlife and humans. For this reason, biodegradation, the major process of phthalic acid ester elimination from the environment, is of global importance. Here, we studied bacterial phthalic acid ester degradation at Saravan landfill in Hyrcanian Forests, Iran, an active disposal site with 800 tons of solid waste input per day. A di-n-butyl phthalate degrading enrichment culture was established from which Paenarthrobacter sp. strain Shss was isolated. This strain efficiently degraded 1 g L–1 di-n-butyl phthalate within 15 h with a doubling time of 5 h. In addition, dimethyl phthalate, diethyl phthalate, mono butyl phthalate, and phthalic acid where degraded to CO2, whereas diethyl hexyl phthalate did not serve as a substrate. During the biodegradation of di-n-butyl phthalate, mono-n-butyl phthalate was identified in culture supernatants by ultra-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry. In vitro assays identified two cellular esterase activities that converted di-n-butyl phthalate to mono-n-butyl phthalate, and the latter to phthalic acid, respectively. Our findings identified Paenarthrobacter sp. Shss amongst the most efficient phthalic acid esters degrading bacteria known, that possibly plays an important role in di-n-butyl phthalate elimination at a highly phthalic acid esters contaminated landfill.

Biodegradation of DEHP by a new native consortium An6 (Gordonia sp. and Pseudomonas sp.) adapted with phthalates, isolated from a natural strongly polluted wetland

Considering the high concentration of phthalic acid esters (PAEs) in Anzali international wetland, up to 40 times higher than the environmental risk limit, the aim of this study was to obtain an effective consortium and native bacteria in the degradation of diethyl hexyl phthalate (DEHP) from sediments of this ecosystem. For this purpose, sediments of 9 stations of Anzali wetland were enriched with PAEs in waterlogged conditions at 30 °C. The results showed that the consortium An6 (containing two cultivable bacteria with phthalate degradation ability, Pseudomonas putida strain ShA (MN298858), and Gordonia alkanivorans strain Sh6 (MK460262.1)) could biodegrade 100, 100, 90.57, and 58.73% of a mixture of DMP, DEP, DBP, and DEHP at high concentration (2000 mg/L each), respectively. The separate DEHP biodegradation by the above consortium showed that it could degrade 97% of 500 mg/L of DEHP in less than 3 days. Additionally, phthalic acid (PA) and monoethyl hexyl phthalate (MEHP) as intermediate products of DEHP biodegradation were identified by UPLC-Q-TOF-MS. Phthalate consumption patterns of strains ShA and Sh6 indicate that there is a possible complementary effect among these bacteria in PAEs biodegradation. The ability of consortium An6 belonging to the most polluted area (20–43 mg/Kg DEHP) of this wetland to degrade DEHP could be caused by the exposure of the microbial community of this area to PAEs over time that gives rise to a possible adaptation. Based on the findings, consortium An6 (with novel composition) and isolated bacteria can be suggested for the efficient remediating of PAEs in the different ecosystems. • Anzali international wetland has biopotential to self-purification of high concentration of phthalates. • The microbial community of the most polluted area of the lagoon has become more compatible with PAEs and is more efficient in phthalates degradation. • The consortium An6 could degrade phthalates at 2000 mg/L in waterlogged conditions. • Gordonia alkanivorans and Pseudomonas putida together cover the biodegradation of a broader spectrum of different PAEs. • Consortium An6 efficiently degraded 500 mg/L of DEHP in less than 3 days.

Occurrence and cross-interface transfer of phthalate esters in the mangrove wetland in Dongzhai Harbor, China

Phthalate esters (PAEs), the most widely used plasticizers, are extensively present in various environmental media, and are continuously transported from land to sea. However, PAEs have not been well characterized in multiple media in mangrove wetlands, an important land-sea interface. This study investigated the distribution and transfer of six PAEs in water, sediment, mangroves, and fish in Dongzhai Harbor. The mangrove forest in Dongzhai Harbor is the largest in China and is surrounded by shrimp ponds and villages. PAEs are ubiquitous in the study area. The mean concentration range of ∑6PAEs was 0.31–1.52 μg/L in water, 450–2096 μg/kg dry weight (dw) in sediment, 210–937 μg/kg dw in mangrove plants, and not detected (n.d.) -205 μg/kg in fish. Among the six PAEs, di-n-butyl phthalate (DBP) and di-ethylhexyl phthalate (DEHP) were predominant. The concentrations of the PAEs in mangrove plants tended to decrease from the river and coast to tidal gullies, which might be related to the periodic inundation of tides. A study of PAEs bioaccumulation showed that the concentration of PAEs in herbivorous fish was higher than that in carnivorous fish. In the same species, larger individuals had a lower concentration of ∑6PAEs. Di-n-octyl phthalate (DnOP) and DEHP tended to transfer from water to sediments, while the four less-hydrophobic PAEs, such as DBP, were more likely to be released from sediments to water. Our results can provide important information of the distribution and fate of PAEs in mangrove wetlands.

Biomonitoring of Phthalates, Bisphenols and Parabens in Children: Exposure, Predictors and Risk Assessment.

Exposure to emerging contaminants, such as phthalates, bisphenols and parabens in children has been associated with possible neurodevelopment and endocrine alterations. In the present study, the biomonitoring of biomarkers in children (5–12 years old) from the Valencia Region (Spain) have been implemented using urines from the BIOVAL program. More than 75% of the children studied (n = 562) were internally exposed (>LOQ) to bisphenols and parabens, and the whole population assessed (n = 557) were exposed to at least one phthalate. The geometric means (GM) of the concentrations of bisphenol A, methyl paraben and propyl paraben were 0.9, 1.4 and 0.39 ng/mL, respectively. Regarding phthalates, monoethyl phthalate GM was 55.0 ng/mL and diethyl hexyl phthalate (as the sum of five metabolites) GM was 60.6 ng/mL. Despite the studied population being widely exposed, the detection frequencies and concentrations were in general lower than in previous studies involving children in Spain and in other countries in recent years. Furthermore, the risk assessment study concluded that the internal exposure to phthalates, bisphenols and parabens is lower than the guidance values established, and, therefore, a health risk derived from the exposure to these compounds in the studied population is not expected.

Development of a Human Estrogen Receptor Dimerization Assay for the Estrogenic Endocrine-Disrupting Chemicals Using Bioluminescence Resonance Energy Transfer.

Endocrine-disrupting chemicals (EDCs) are found in food and various other substances, including pesticides and plastics. EDCs are easily absorbed into the body and have the ability to mimic or block hormone function. The radioligand binding assay based on the estrogen receptors binding affinity is widely used to detect estrogenic EDCs but is limited to radioactive substances and requires specific conditions. As an alternative, we developed a human cell-based dimerization assay for detecting EDC-mediated ER-alpha (ERα) dimerization using bioluminescence resonance energy transfer (BRET). The resultant novel BRET-based on the ERα dimerization assay was used to identify the binding affinity of 17β-estradiol (E2), 17α-estradiol, corticosterone, diethylhexyl phthalate, bisphenol A, and 4-nonylphenol with ERα by measuring the corresponding BRET signals. Consequently, the BRET signals from five chemicals except corticosterone showed a dose-dependent sigmoidal curve for ERα, and these chemicals were suggested as positive chemicals for ERα. In contrast, corticosterone, which induced a BRET signal comparable to that of the vehicle control, was suggested as a negative chemical for ERα. Therefore, these results were consistent with the results of the existing binding assay for ERα and suggested that a novel BRET system can provide information about EDCs-mediated dimerization to ERα.

Effects of selected functional groups on nanoplastics transport in saturated media under diethylhexyl phthalate co-contamination conditions

The production and degradation of plastic remains can result in nanoplastics (NPs) formation. However, insufficient information regarding the environmental behaviors of NPs impedes comprehensive assessment of their significant threats. In this study, the transport behavior of unmodified NPs (PSNPs), carboxyl-modified NPs (PSNPs−COOH), and amino-modified NPs (PSNPs−NH2) was investigated using column experiments in the presence and absence of goethite (GT) and diethylhexyl phthalate (DEHP). Quantum chemical computation was performed to reveal the transport mechanisms. The results showed that GT decreased the transport of NPs and the presence of DEHP decreased it further. Van der Waals forces and small electrostatic interactions coexisted between the PSNPs and GT and caused deposition. Ligand exchange caused greater deposition of PSNPs−COOH on GT-coated sand than that of PSNPs. Although hydrogen bonding existed between the DEHP and NPs with functional groups, an increase in the positive charge and chemical heterogeneity of the collector was the main reason for DEHP promoting the deposition of NPs. Because of low absolute negative zeta potential values, PSNPs−NH2 was sensitive to chemical heterogeneity, and thus fully deposited (over 96.9%) in GT and GT-DEHP-coated columns. Generally, the deposition of NPs due to chemical heterogeneity was more significant than that due to the formation of chemical bonds and van der Waals, electrostatic, and hydrogen interactions. Our results highlight that the surface charge and functional groups significantly influence the transport behaviors of NPs and elucidate the fate of NPs in the terrestrial environment.