Di-(2-ethylhexyl) Phthalate Concentrations Research Articles

Comparative analysis biochar and compost-induced degradation of di-(2-ethylhexyl) phthalate in soils

In recent years, biochar has been extensively studied as a sorbent for immobilizing contaminants and minimizing their bioavailability in soils. Few studies have been conducted to evaluate the interactions between biochar and compost in soils and their impact on degradation of organic contaminants. In the present study, soils with high organic carbon content (HOC) and low organic carbon content (LOC) were spiked with 100mg·kg−1 di-(2-ethylhexyl) phthalate (DEHP) amended with biochar derived from dead pigs, bamboo, and composted sheep manure. The soils were thereafter incubated for 112days at 25°C and periodically sampled for monitoring DEHP concentrations. Degradation of DEHP was described by a logistic model. Results showed that the initial degradation rates were slow, but accelerated after 14days of incubation. The DEHP degradation rates were higher in the HOC soils than in the LOC soils over the incubation period. The half-lives of DEHP were shorter in the LOC soils treated with pig biochar, and bamboo/pig biochar plus compost than in the untreated soil. However, there was no significant difference in the half-lives of DEHP in the HOC control and treated soils. The differential effects of soil amendments on DEHP degradation between LOC and HOC soils could be explained by the properties of the organic amendments, soil pH and the organic carbon contents of the soils.

Caracterización parcial de esterasas de Fusarium culmorum crecido en presencia de di(2-etil hexil ftalato) en fermentación sólida y sumergida

Di (2-ethylhexyl) phthalate (DEHP) is a plasticizer used in the polyvinyl chloride (PVC) industry. The indiscriminate use of various products manufactured with PVC, causes this plasticizer to be considered a contaminant. Fusarium culmorum is a phytopathogenic fungus that has the ability to produce esterase enzymes. Esterases are of great importance because they can break the ester bonds present in the plasticizers. In this work, the activity of esterases produced by F. culmorum grown in media supplemented with different concentrations of DEHP (1500 and 2000 mg/L) in solid-state fermentation and submerged fermentation was characterized by biochemical tests and polyacrylamide gel electrophoresis. F. culmorum showed higher esterase activity in media supplemented with 1500 and 2000 mg DEHP/L in solid-state fermentation. A greater number of esterase activity bands were observed in the DEHP-supplemented media, having a molecular weight of about 20, 25, 37, 45, 55, 75 and 150 kDa, in both fermentation systems. 1500 mg of DEHP/L induced a higher production of esterases, demonstrating that high concentrations of DEHP did not inhibit the enzymatic production of the fungus.

Women Diagnosed with Endometriosis Show High Serum Levels of Diethyl Hexyl Phthalate.

Background:Endometriosis is one of the common causes of infertility with very diverse etiology. In modern lifestyle, humans are exposed to several endocrine-disrupting chemicals (EDCs) which may lead to reproductive disturbances. Diethyl hexyl phthalate (DEHP) is one of the common EDCs to which women are exposed by the use of cosmetics, perfumes, food packaging, medicine, and insecticides.Aim:The aim of this study was to measure the levels of DEHP in women diagnosed with endometriosis and healthy females and to compare these levels among different stages of endometriosis.Setting and Design:This descriptive study was conducted at a tertiary care hospital.Subjects and Methods:This study comprised of fifty women diagnosed with endometriosis, aged 20–40 years, and fifty age-matched healthy, fertile women without endometriosis. Females on any medication/comorbid conditions were excluded from the study. Serum DEHP concentrations were measured by high-performance liquid chromatography (HPLC). The results were expressed as means ± standard deviation (SD) (ng/ml of DEHP).Statistical Analysis:Data were analyzed using IBM-SPSS version 20. Two-sample Student's t-test and one-way ANOVA were applied for the analysis.Results:The mean ± SD value of DEHP in cases was 65.29 ± 21.69 ng/ml; however, the mean ± SD value of DEHP in controls was undetectable. Comparison of DEHP among stages of endometriosis revealed an increasing trend with advanced stages (III and IV). The values were not different between the two age groups of women with endometriosis (20–30 and 31–40 years).Conclusion:High levels of DEHP in women diagnosed with endometriosis suggest a role of phthalates in the etiology of endometriosis and permit careful use of such compounds.

Phthalate exposure promotes chemotherapeutic drug resistance in colon cancer cells.

Phthalates are widely used as plasticizers. Humans can be exposed to phthalates through ingestion, inhalation, or treatments that release di(2-ethylhexyl) phthalate (DEHP) and its metabolite, mono(2-ehylhexyl) phthalate (MEHP), into the body from polyvinyl chloride-based medical devices. Phthalate exposure may induce reproductive toxicity, liver damage, and carcinogenesis in humans. This study found that colon cancer cells exposed to DEHP or MEHP exhibited increased cell viability and increased levels of P-glycoprotein, CD133, Bcl-2, Akt, ERK, GSK3β, and β-catenin when treated with oxaliplatin or irinotecan, as compared to control. The P-glycoprotein inhibitor, tariquidar, which blocks drug efflux, reduced the viability of DEHP- or MEHP-treated, anti-cancer drug-challenged cells. DEHP or MEHP treatment also induced colon cancer cell migration and epithelial-mesenchymal transformation. Elevated stemness-related protein levels (β-catenin, Oct4, Sox2, and Nanog) and increased cell sphere sizes indicated that DEHP- or MEHP-treated cells were capable of self-renewal. We also found that serum DEHP concentrations were positively correlated with cancer recurrence. These results suggest phthalate exposure enhances colon cancer cell metastasis and chemotherapeutic drug resistance by increasing cancer cell stemness, and that P-glycoprotein inhibitors might improve outcomes for advanced or drug-resistant colon cancer patients.

The risk of missed abortion associated with the levels of tobacco, heavy metals and phthalate in hair of pregnant woman: A case control study in Chinese women.

To assess the association between exposure to the tobacco, heavy metals and phthalate on early pregnancy and missed abortion.42 women with missed abortion and 57 matched controls (women with normal pregnancies) were recruited between March and May 2012, from the Department of Gynecology and Obstetrics, First Affiliated Hospital of Guangxi Medical University and the People Hospital of Guangxi Zhuang Autonomous Region. The questionnaire survey was carried on to learn about the basic conditions, as well as smoking history of all participants. The levels of tobacco, heavy metal, and phthalate exposure were compared between the 2 groups by measuring nicotine, cocaine, cadmium (Cd), manganese (Mn), plumbum (Pb) and dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), di-2-ethyl hexyl phthalate (DEHP) in the hair samples.Out results showed that significant differences in age (P = .042), premarital examination (P = .041), passive smoking (P = .021), and heavy metal exposure (P = .022) were found in the case group compared to the control. In addition, the concentration of nicotine (P = .037), cotinine (P = .018), Cd (P = .01), Pb (P = .038) and DEHP (P = .001) in the hair were significantly higher in the case group. Furthermore, logistic analysis revealed that age [Odds Ratio (OR) 1.172, 95% confidence interval (CI) 1.036–1.327], Cd (OR 8.931, 95% CI 2.003–39.811), Cotinine (OR 4.376, 95% CI 1.159–16.531), DEHP (OR 1.863, 95% CI 1.103–3.146) were important factors contributing to the missed abortion (P < .05).It was demonstrated that high gestational age, passive smoking, heavy metals, and the phthalate exposure were the risk factors for missed abortion, while the premarital health examination was a protective factor. Avoiding these harmful substances before getting pregnant and during the early stages of pregnancy, might help prevent missed abortions.

Di-2-ethylhexyl phthalate (DEHP) exposure disturbs lipid metabolism in juvenile yellow catfish Tachysurus fulvidraco.

This study was conducted to determine the mechanism by which di-2-ethylhexyl phthalate (DEHP) exposure influences lipid metabolism of juvenile yellow catfish Tachysurus fulvidraco. Fish were exposed to three DEHP concentrations (0, 0·1 and 0·5 mg l-1 DEHP) for 8 weeks. Fatty acid synthase (FAS) activity significantly decreased with increasing DEHP concentrations, the highest value was in the Tween control group, whereas the lowest activities of carnitine palmitoyltransferase (CPT) and lipoprotein lipase (LPL) were in this group. The messenger (m)RNA levels of 6-phospho-gluconate dehydrogenase (6PGD), FAS and acetyl-CoA carboxylase a (ACCa) significantly increased with increasing DEHP concentration, the highest values were in the 0·5 mg l-1 DEHP group. The mRNA level of peroxisome proliferator-activated receptor γ (PPARγ) was lower in Tween control than in fish exposed to 0·1 and 0·5 mg l-1 DEHP. The highest mRNA level of ACCb was in the 0·1 mg l-1 DEHP group. These results indicate that DEHP exposure can disturb lipid metabolism at the enzymatic and mRNA levels in Pelteobagrus fulvidraco.

Reproductive effects linked to DNA methylation in male zebrafish chronically exposed to environmentally relevant concentrations of di-(2-ethylhexyl) phthalate.

Di-(2-ethylhexyl) phthalate (DEHP) possesses the potential to interfere with the male reproductive endocrine system in mammals; however, its reproductive toxicity in male zebrafish and associated epigenetic studies have not been explored. In this study, three-month-old male zebrafish were exposed to environmentally relevant concentrations of DEHP (0, 10, 33 and 100μg/L) for 3 months, and then the impact on the reproduction of males and the underlying mechanism were investigated. Histological testing showed that an exposure concentration of 100μg/L DEHP significantly inhibited spermatogenesis, with an associated decline in capability to fertilize untreated oocytes. Electron microscopic examinations also revealed noticeable damage to the testicular ultrastructure at the 100μg/L DEHP exposure level. In addition, exposure to 33 and 100μg/L of DEHP resulted in a decline of circulating testosterone (T) and an increase in the level of 17β-estradiol (E2), both of which were possibly derived from the downregulation of cyp17a1 and hsd17b3 genes and the upregulation of the cyp19a1a gene in the gonads. The DNA methylation statuses of these genes were altered within their promoter regions. A significant increase in global DNA methylation in both the male testes and their offspring larvae was observed at higher exposure concentration of DEHP. Our findings demonstrate that exposure to environmentally relevant concentrations of DEHP can damage the testes, disturbe the sex hormones production, and inhibite spermatogenesis, which ultimately impairs the reproduction of male zebrafish.

Occurrence, distribution, and ecological risks of phthalate esters in the seawater and sediment of Changjiang River Estuary and its adjacent area

A total of 133 seawater samples and 17 sediment samples were collected from 81 sampling sites in the Changjiang River Estuary and its adjacent area and were analyzed for 16 phthalate esters (PAEs). The Σ16 PAE concentrations in the seawater and sediment samples ranged from 180.3ng·L−1 to 3421ng·L−1 and from 0.48μg·g−1 to 29.94μg·g−1dry weight (dw), respectively, with mean values of 943.6ng·L−1 and 12.88μg·g−1. The distribution of ∑16PAE concentrations in the water column showed that PAE concentrations in the bottom samples were higher than those in the surface samples (except the transect C located inside the Changjiang River Estuary), with the maxima appearing in the bottom layer at the offshore stations. Among the 16 PAEs, di (2-ethylhexyl) phthalate (DEHP), diisobutyl phthalate (DiBP), and dibutyl phthalate (DnBP) dominated the PAEs, with 25.1%, 21.1%, and 18.9% of the Σ16PAEs in seawater, respectively. The comparison of ∑16PAEs and salinities in transects C and A6 suggested that the Changjiang River runoff was an important driving factor influencing the distribution of PAEs. DEHP concentrations in water samples and DEHP and DnBP concentrations in sediment samples exceeded the environmental risk levels (ERL), indicating their potential hazard to the ocean environment.

Evidence of high di(2-ethylhexyl) phthalate (DEHP) exposure due to tainted food intake in Taiwanese pregnant women and the health effects on birth outcomes

The contamination of a clouding agent with di(2-ethylhexyl) phthalate (DEHP), a substitute emulsifier-containing compound used in a variety of foods was announced on May 23, 2011. The aims of this study were as follows (1) compare the urine phthalates (PAE) metabolites concentration and estimate the daily intake (DI) of PAEs in pregnant women before and after the tainted food scandal and (2) examine the effect of relatively high PAEs exposure on birth outcome.One-hundred twelve pregnant women in Northern Taiwan participated in this study from March to December 2010, i.e., before the tainted food scandal. After the tainted food scandal, we collected 69, 73, and 180 urine specimens (January 2013 to August 2014) from women whom were in their first, second, and third trimesters of pregnancy, respectively. We measure urinary DEHP metabolite concentrations to estimate the DI of DEHP and the hazard quotient (HQ) of subjects. This was the first study to assess the effects of DEHP-tainted food scandal exposure in pregnant women across the three trimesters of pregnancy.After the tainted food report, the concentrations of urine PAE metabolite were significantly decreased, especially those of DEHP metabolites. Based on different reference limit values, the percentages of pregnant women whose HQDEHP value exceeded the limit ranged from 0.53% to 8.93%. Despite this low frequency, the higher ΣPAE exposure during the second trimester may significantly increase the risk of relatively low birth height compared to the lower exposure group (β=−0.63 (−1.20 to −0.06)).Our results support the hypothesis that exposure to relatively high concentrations of DEHP in pregnant Taiwanese women may have an adverse effect on birth outcomes. The percentage of subjects whose exposure level exceeded the exposure limit was low; however, high PAEs exposure appears to be significantly associated with birth outcomes. Therefore, we suggest that reference dose for PAEs should be revised.

Effects of di‐(2‐ethylhexyl) phthalate on microbial biomass carbon and microbial community structural diversity in a Mollisol

SummaryOne of the most common persistent organic pollutants is di‐(2‐ethylhexyl) phthalate (DEHP), which has caused considerable pollution in the Mollisols of agricultural areas in northeast China. This research investigates the effects of different concentrations of DEHP from 0 to 35 days on microbial biomass carbon (MBC) and structural diversity in the microbial community of Mollisols. The results indicated that contamination by DEHP of more than 20 mg kg−1 could clearly affect MBC and structural diversity of the microbial community of a Mollisol in a short time depending on the dose of DEHP. At concentrations of DEHP &gt;20 mg kg−1, we observed that the larger was the concentration of DEHP, the greater was the effect on the MBC and diversity of the soil microbial community. The DEHP concentration or incubation time had negative correlations with MBC, and the evenness (EH), Shannon (H) and richness (S) indices of the microbial community, and the DEHP concentration had a dominant effect on microbial properties. The dominant bacterium in the DEHP‐contaminated soil was Bacillus. Furthermore, bacterial community structure changed under different amounts of DEHP stress and with the increase in incubation time; Pseudomonas and Sphingopyxis clearly increased in number with large concentrations of DEHP. The change in the microbial population indicated that these two bacteria might have a strong resistance to change under the microbial DEHP stress.Highlights DEHP significantly changed MBC and microbial diversity of a Mollisol. The change in MBC was related to the composition of the soil microbial community structure. DEHP had a persistent effect on the microbial community in a Mollisol. Bacillus were the dominant bacteria in the DEHP‐contaminated soil.

A novel biodegradation pathway of the endocrine-disruptor di(2-ethyl hexyl) phthalate by Pleurotus ostreatus based on quantum chemical investigation

Di(2-ethyl hexyl) phthalate (DEHP) is a plasticizer that interfere with endocrine systems in mammals. Growth parameters for Pleurotus ostreatus grown on media containing glucose and different concentrations of DEHP (0, 500 and 1000mg/L) were evaluated. The highest biomass production was observed in medium supplemented with 1000mg of DEHP/L. Half-life of DEHP biodegradation, biodegradation constant of DEHP, and percentage of removal efficiency (%E) were also determined. P. ostreatus degraded 100% of DEHP after 504h. %E was 99.3% and 98.4% for 500 and 1000mg of DEHP/L, respectively. Intermediate compounds of biodegraded DEHP were identified by GC-MS and a DEHP biodegradation pathway was proposed using quantum chemical investigation. DEHP might be metabolized through three pathways; a de-esterification pathway, an oxidation pathway and an oxidation-hydrolysis pathway, forming phthalic acid, acetic acid and butanediol, respectively. P. ostreatus degrades and uses (as carbon and energy source) high concentrations of DEHP.

Biphasic modulation of neuro- and interrenal steroidogenesis in juvenile African sharptooth catfish (Clarias gariepinus) exposed to waterborne di-(2-ethylhexyl) phthalate

Receptor (i.e. genomic) and non-receptor (or non-genomic) effects of endocrine toxicology have received limited or almost non-existent attention for tropical species and regions. In the present study, we have evaluated the effects of di-(2-ethylhexyl) phthalate (DEHP) on neuro- and interrenal steroidogenesis of the African catfish (Clarias gariepinus) using molecular, immunochemical and physiological approaches. Juvenile fish (mean weight and length: 5.6±0.6g and 8.2±1.2cm, respectively), were randomly distributed into ten 120L rectangular glass tanks containing 60L of dechlorinated tap water, at 50 fish per exposure group. The fish were exposed to environmentally relevant concentrations of DEHP, consisting of 0 (ethanol solvent control), 10, 100, 200, and 400μg DEHP/L water and performed in two replicates. Brain, liver and head kidney samples were collected at day 3, 7 and 14 after exposure, and analysed for star, p450scc, cyp19a1, cyp17, cyp11β-, 3β-, 17β- and 20β-hsd, and 17β-ohase mRNA expression using real-time PCR. The StAR, P450scc and CYP19 proteins were measured using immunoblotting method, while estradiol-17β (E2) and testosterone (T) were measured in liver homogenate using enzyme immunoassay (EIA). Our data showed a consistent and unique pattern of biphasic effect on star and steroidogenic enzyme genes with increases at low concentration (10μg/L) and thereafter, a concentration-dependent decrease in both the brain and head kidney, that paralleled the expression of StAR, P450scc and CYP19 proteins. Cellular E2 and T levels showed an apparent DEHP concentration-dependent increase at day 14 of exposure. The observed consistency in the current findings and in view of previous reports on contaminants-induced alterations in neuro- and interrenal steroidogenesis, the broader toxicological and endocrine disruptor implication of our data indicate potentials for overt reproductive, metabolic, physiological and general health consequences for the exposed organisms.

Phthalates in dust collected from various indoor environments in Beijing, China and resulting non-dietary human exposure

This study measured concentrations of fifteen phthalates in dust from homes (n = 19), offices (n = 10), kindergartens (n = 5) and public places (n = 7) in Beijing, China, during April 2010 and May 2011. We examined phthalate co-occurrence in dust collected from different indoor surfaces and estimated daily exposure to phthalates via dust ingestion, inhalation, and dermal absorption. Diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di (2-Ethylhexyl) phthalate (DEHP) were the most abundant phthalates in each of the investigated environments (medians: 58.1–272 μg/g, 31.2–145 μg/g, and 202–1310 μg/g, respectively), with detection frequencies greater than 90% except for DiBP in dust from homes. Diethyl phthalate (DEP) was detected only in homes, with a detection frequency of 42%. The detection frequency of dinonyl phthalate (DNP) was 80% in public places (median: 78.8 μg/g). DnBP, DiBP and DEHP concentrations in different indoor environments differed significantly (p < 0.05). Our findings suggest that DnBP, DiBP and DEHP originate from the same sources, while DNP has several sources. DEHP exposure is the highest for infants, children and adults. The exposure doses of DnBP and DEHP decrease as age increases. Dermal absorption from air is the main pathway for DiBP and DnBP, contributing from 56.4% to 84.7% of the total exposure. Dust ingestion is the main pathway for DEHP, contributing from 85.6% to 96.6% of the total exposure.

Di (2-ethylhexyl) phthalate exposure impairs meiotic progression and DNA damage repair in fetal mouse oocytes in vitro

Di (2-ethylhexyl) phthalate (DEHP), is the most common member of the class of phthalates that are used as plasticizers and have become common environmental contaminants. A number of studies have shown that DEHP exposure impacts reproductive health in both male and female mammals by acting as an estrogen analog. Here, we investigated the effects of DEHP on meiotic progression of fetal mouse oocytes by using an in vitro model of ovarian tissue culture. The results showed that 10 or 100 μM DEHP exposure inhibited the progression of oocytes throughout meiotic prophase I, specifically from the pachytene to diplotene stages. DEHP possibly impairs the ability to repair DNA double-strand breaks induced by meiotic recombination and as a consequence activates a pachytene check point. At later stages, such defects led to an increased number of oocytes showing apoptotic markers (TUNEL staining, expression of pro-apoptotic genes), resulting in reduced oocyte survival, gap junctions, and follicle assembly in the ovarian tissues. Microarray analysis of ovarian tissues exposed to DEHP showed altered expression of several genes including some involved in apoptosis and gonad development. The expression changes of some genes clustered in cell-cell communication and signal transduction, along with plasma membrane, extracellular matrix and ion channel function classes, were dependent on the DEHP concentration. Together, these results bring new support to the notion that exposure to DEHP during gestation might exert deleterious effects on ovary development, perturbing germ cell meiosis and the expression of genes involved in a wide range of biological processes including ovary development.

Prenatal exposure estimation of BPA and DEHP using integrated external and internal dosimetry: A case study

Prenatal exposure to Endocrine disruptors (EDs), such as Bisphenol A (BPA) and di (2-ethylhexyl) phthalate (DEHP), has been associated with obesity and diabetes diseases in childhood, as well as reproductive, behavioral and neurodevelopment problems. The aim of this study was to estimate the prenatal exposure to BPA and DEHP through food consumption for pregnant women living in Tarragona County (Spain). Probabilistic calculations of prenatal exposure were estimated by integrated external and internal dosimetry modelling, physiologically based pharmacokinetic (PBPK) model, using a Monte-Carlo simulation. Physical characteristic data from the cohort, along with food intake information from the questionnaires (concentrations of BPA and DEHP in different food categories and the range of the different food ratios), were used to estimate the value of the total dietary intake for the Tarragona pregnancy cohort. The major contributors to the total dietary intake of BPA were canned fruits and vegetables, followed by canned meat and meat products. In turn, milk and dairy products, followed by ready to eat food (including canned dinners), were the most important contributors to the total dietary intake of DEHP. Despite the dietary variations among the participants, the intakes of both chemicals were considerably lower than their respective current tolerable daily intake (TDI) values established by the European Food Safety Authority (EFSA). Internal dosimetry estimates suggest that the plasma concentrations of free BPA and the most important DEHP metabolite, mono (2-ethylhexyl) phthalate (MEHP), in pregnant women were characterized by transient peaks (associated with meals) and short half-lives (< 2 h). In contrast, fetal exposure was characterized by a low and sustained basal BPA and MEHP concentration due to a lack of metabolic activity in the fetus. Therefore, EDs may have a greater effect on developing organs in young children or in the unborn child.

SELECTIVE EXTRACTION AND DETERMINATION OF DI (2-ETHYLHEXYL) PHTHALATE IN AQUEOUS SOLUTION BY HPLC COUPLED WITH MOLECULARLY IMPRINTED SOLID-PHASE EXTRACTION

Surface Molecularly Imprinted Polymer (SMIP) for selective adsorption of di(2-ethylhexyl) phthalate(DEHP) was prepared on the surface of silica gel which was modified by aminopropyltriethoxysilane and acryloyl chloride in a two-step method. The prepared SMIP was used to prepare Molecularly Imprinted Solid-Phase Extraction (MISPE) column for selective extraction of DEHP from aqueous solution. The results suggested that MISPE column had high affinity and excellent selectivity for DEHP. And adsorption property of MISPE column was significantly superior to the commercial C18 column. The MISPE column was reusable. An analytical method MISPE-HPLC was developed for extraction and determination of the DEHP residues in environmental water samples. The results showed that the linear relationship between the peak area and the concentration of DEHP were as follow: y=2354.6x+1663.5 with a good correlation coefficient (R2=0.9997) and the detection and quantification limits reached 0.012 mg/L and 0.039 mg/L, respectively. The spiked recoveries of DEHP in river water and lake water sample were in the range from 93.3% to 102.3 % at the spiked level of 50~1000 μg/L. The Relative Standard Deviations (RSD) were less than 5.2%.

Association of prenatal urinary phthalate metabolite concentrations and childhood BMI and obesity.

BackgroundAlthough experiments in animals suggest that phthalates may have obesogenic effects, studies on prenatal exposure in children show inconsistent results.MethodsWe measured urinary concentrations of 11 phthalate metabolites collected twice during pregnancy from mothers participating in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort study (N=345). Height, weight, waist circumference, and percent body fat were assessed in their children between 5 and 12 years of age. We used generalized estimating equations to examine associations at each age and tested for interaction by sex.ResultsMetabolites of diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate, and di(2-ethylhexyl) phthalate (DEHP) were positively associated with BMI z-score, waist circumference z-score, and percent body fat at multiple ages. At age 12, we observed increased odds of being overweight/obese with each doubling of prenatal concentrations of DEP (odds ratio=1.3; 95% confidence intervals: 1.1, 1.4), DBP (1.2; 1.0, 1.4), and DEHP (1.3; 1.0, 1.6) metabolites. Results were similar in boys and girls except for DBP metabolites and the non-specific metabolite mono-(3-carboxypropyl) phthalate, which showed positive associations only in boys.ConclusionIn utero exposure to certain phthalates is associated with increased BMI and risk for overweight/obesity in childhood.

Removal of phthalic acid diesters through a municipal solid waste landfill leachate treatment process

We studied the removal of two phthalic acid diesters (PAEs), di-n-butyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), from leachates of a municipal solid waste landfill treatment facility. The leachates originated from the adjusting unit, the anaerobic unit, the aerobic unit, the ultrafiltration membrane unit, and the reverse osmosis membrane unit. The initial concentrations of DBP and DEHP were 225.8 and 260.9 µg/L, respectively, which were reduced to 5.8 and 3.2 µg/L in the effluent, representing 97.4% removal of DBP and 98.8% removal of DEHP. DBP was removed stepwise during the process, mainly via degradation by microorganisms. Approximately, 70.1% of the DEHP was removed by the membrane processes, owing to physical retention of the compound by the membranes. The dissolved organic carbon occurred mostly in the 1–100 kDa molecular weight fraction. The positive correlation between dissolved organic carbon and DBP/DEHP concentrations in raw leachate and in effluents from each treatment unit showed that the interaction between dissolved organic matter and PAEs facilitated the removal of organic pollutants. Large amounts of PAEs can accumulate over long periods of time in the concentrated leachate product, which may make further leachate treatment more difficult and may lead to adverse impacts on the environment.

Long-term di (2-ethylhexyl)-phthalate exposure promotes proliferation and survival of HepG2 cells via activation of NFκB

Di (2-ethylhexyl)-phthalate (DEHP) is the most commonly used plasticizer. DEHP can easily leach out from products into the environment and has become a significant environmental contamination. However, its carcinogenic effects in human remain controversial. In this study, we exposed hepatocellular carcinoma HepG2 cells to different concentrations of DEHP for a period of times, followed by a combination of RNA-seq analysis and molecular analysis for DEHP-altered genes. We observed that long-term and very low-dose DEHP treatment has growth-inducing activity in HepG2 cells, while short-term and high-dose DEHP treatment has little effects on tumor cell proliferation. Bioinformatic analysis further revealed that a large subset of differentially expressed genes affected by DEHP have functional annotations related to inflammation response. Importantly we found that long-term DEHP treatment stimulated nuclear factor-kappa B (NF-κ B) activity in HepG2 cells, while inhibition of NFκB activity could offset the effects of DEHP exposure. In conclusion, continuous DEHP treatment could promote proliferation of HepG2 cells via activating NFκB signaling pathway.

Phthalate release in leachate from municipal landfills of central Poland.

Phthalate diesters (PAEs) are used as plasticizer additives to polymer chains to make the material more flexible and malleable. PAEs are bonded physically, not chemically, to the polymeric matrix and can migrate to and leach from the product surface, posing a serious danger to the environment and human health. There have been a number of studies on PAE concentrations in landfill leachate conducted in the EU and around the world, though few in Poland. In the present study, the leachate of five municipal landfills was analyzed for the presence of PAEs. Raw leachate was sampled four times over the period of one year in 2015/16. It was the first large study on this subject in Poland. PAEs were detected in the leachate samples on all of the landfills, thereby indicating that PAEs are ubiquitous environmental contaminants. The following PAEs were detected in at least one sample: Di(2-ethylhexyl) phthalate (DEHP), Diethyl phthalate (DEP), Dimethyl phthalate (DMP), Di-n-butyl phthalate (DBP), Di-isobutylphthalate (DIBP). Out of all ten PAEs, DEHP was the most predominant, with concentrations up to 73.9 μg/L. DEHP was present in 65% of analyzed samples (in 100% of samples in spring, 80% in winter, and 40% in summer and autumn). In only 25% of all samples DEHP was below the acceptable UE limit for surface water (1.3 μg/L), while 75% was from 1.7 to 56 times higher than that value. On the two largest landfills DEHP concentrations were observed during samples from all four seasons, including on a landfill which has been remediated and closed for the last 5 years.