Concentrations Of Phthalate Esters Research Articles

Analysis of trace contamination of phthalate esters in ultrapure water using a modified solid-phase extraction procedure and automated thermal desorption–gas chromatography/mass spectrometry

The present study was aimed to develop a procedure modified from the conventional solid-phase extraction (SPE) method for the analysis of trace concentration of phthalate esters in industrial ultrapure water (UPW). The proposed procedure allows UPW sample to be drawn through a sampling tube containing hydrophobic sorbent (Tenax TA) to concentrate the aqueous phthalate esters. The solid trap was then demoisturized by two-stage gas drying before subjecting to thermal desorption and analysis by gas chromatography–mass spectrometry. This process removes the solvent extraction procedure necessary for the conventional SPE method, and permits automation of the analytical procedure for high-volume analyses. Several important parameters, including desorption temperature and duration, packing quantity and demoisturizing procedure, were optimized in this study based on the analytical sensitivity for a standard mixture containing five different phthalate esters. The method detection limits for the five phthalate esters were between 36 ng l −1 and 95 ng l −1 and recovery rates between 15% and 101%. Dioctyl phthalate (DOP) was not recovered adequately because the compound was both poorly adsorbed and desorbed on and off Tenax TA sorbents. Furthermore, analyses of material leaching from poly(vinyl chloride) (PVC) tubes as well as the actual water samples showed that di- n-butyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) were the common contaminants detected from PVC contaminated UPW and the actual UPW, as well as in tap water. The reduction of DEHP in the production processes of actual UPW was clearly observed, however a DEHP concentration of 0.20 μg l −1 at the point of use was still being quantified, suggesting that the contamination of phthalate esters could present a barrier to the future cleanliness requirement of UPW. The work demonstrated that the proposed modified SPE procedure provided an effective method for rapid analysis and contamination identification in UPW production lines.

Evaluation of the Phthalate Esters in South Indian Women with Endometriosis

Background: To evaluate the possible association between phthalate esters (PEs) and the occurrence of endometriosis. Blood samples were collected from 99 infertile women with endometriosis (study group); 135 age-matched women without endometriosis (control group) but with infertility related to tubal defects, fibroids, polycystic ovaries, idiopathic infertility and pelvic inflammatory diseases diagnosed by laparoscopy with no evidence of endometriosis or other gynecological disorders during laparoscopic sterilization. Materials and Methods: This is a prospective case-control study, which recruited women undergoing infertility treatment at three collaborating centers (BMMHRC: Bhagwan Mahavir Medical Hospital and Research Centre, MHRT: Maternal Health and Research Trust, and Owaisi Hospital and Research Center) of Reproductive Medicine Hyderabad, which receives cases from all over the region of Andhra Pradesh, India. The concentrations of Phthalate Esters were measured by using the High Performance Liquid Chromatography (HPLC). Evaluation of Phthalate Esters concentrations in women with endometriosis compared with women who are free from the disease. Results: Women with endometriosis showed significantly higher concentrations of Phthalate esters (Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Di-n-butyl phthalate (DnBP), Butyl benzyl phthalate (BBP) and Bis (2-ethylhexyl) phthalate (BEHP)) compared with control group. We found that (38%) of the cases with endometriosis and (21%) of the control group. The correlation between the concentrations of Phthalate esters and different severity of endometriosis was strong and statistically significant at p<0.05 for all five compounds (DMP): r=+0.57, p<0.0001; DnBP r=+0.39, p<0.0001; BBP: r=+0.89, p<0.0001; DnOP: r=+0.66, p<0.0001 and BEHP: r=+0.33, p<0.0014. Conclusion: This study for the first time from Indian subcontinent demonstrates that possibly Phthalate Esters might have a role in etiology of endometriosis.

Distribution of persistent toxic substances in benthic bivalves from the inshore areas of the Yellow Sea

A baseline survey of trace metals and organic pollutants in bivalves from the coastal areas of the Yellow Sea (China) showed the the concentrations of Cd and Pb in the bivalves from more than 85 and 73%, respectively, of the total sites (30 sites in all) exceeded the low limits of the national quality standards for marine organisms. At three sites, the contents of Cd in three species were even higher than the median limit, and a similar case with Pb occurred at another site. The tissue concentrations of As at four sites and of Hg at one site were above the low and the median limits, respectively, of the quality standards. At 43% of all sites, the levels of petroleum hydrocarbons were higher than the low limit of the quality standards, and the tissue concentrations at two sites even went beyond the median limit at one site and the high limit at the other. The concentrations of phthalate esters and polycyclic aromatic hydrocarbons (PAHs) in the collected bivalves were not high, as shown by peak values of 305 and 302 ng/g, respectively. The contents of polychlorinated biphenyls for all the species were much lower than the low limit of the quality standards. The compositional properties and isomeric ratios of PAHs indicated various pyrolytic procedures as the dominant origins. The sites with higher tissue contents of DDT and its metabolites (DDTs) over the low or the median quality limit were located mainly in the South Yellow Sea. The fractions and specific ratios of DDTs suggested that new inputs of DDT existed at two sites in the North Yellow Sea, and the potential sources involved technical DDT, technical dicofol, and their mixture.

The Association between Phthalates in Dust and Allergic Diseases among Bulgarian Children

BackgroundRecent studies have identified associations between the concentration of phthalates in indoor dust and allergic symptoms in the airways, nose, and skin.ObjectivesOur goal was to investigate the associations between allergic symptoms in children and the concentration of phthalate esters in settled dust collected from children’s homes in Sofia and Burgas, Bulgaria.MethodsDust samples from the child’s bedroom were collected. A total of 102 children (2–7 years of age) had symptoms of wheezing, rhinitis, and/or eczema in preceding 12 months (cases), and 82 were nonsymptomatic (controls). The dust samples were analyzed for their content of 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 (DnOP).ResultsA higher concentration of DEHP was found in homes of case children than in those of controls (1.24 vs. 0.86 mg/g dust). The concentration of DEHP was significantly associated with wheezing in the preceding 12 months (p = 0.035) as reported by parents. We found a dose–response relationship between DEHP concentration and case status and between DEHP concentration and wheezing in the preceding 12 months.ConclusionsThis study shows an association between concentration of DEHP in indoor dust and wheezing among preschool children in Bulgaria.

Occurrence of phthalate esters in water and sediment of urban lakes in a subtropical city, Guangzhou, South China

Extensive use of phthalate esters (PAEs) in both industrial processes and consumer products has resulted in the ubiquitous presence of these chemicals in the environment. This study reports the first data on the concentrations of 16 phthalate esters (PAEs) in water and sediments of the urban lakes in Guangzhou City. PAEs were detected in all samples analyzed, mainly originating from urban stormwater runoff, atmospheric deposition, as well as untreated discharge of industrial wastewater and municipal sewage. The Σ16PAEs concentrations in water and sediments ranged from 1.69 to 4.72 μg L−1 and 2.27 to 74.94 μg g−1—dry weight (dw), with the mean concentrations of 2.91 μg L−1 and 20.85 μg g−1—dw, respectively, which indicates that sediment is a significant sink for PAEs. Variability of the Σ16PAEs concentrations in water and sediment in the urban lakes was almost consistent. The spatial distribution of PAEs was site-specific. Of the 16 PAEs, DMP, DEP, DnBP, DiBP, DMPP, and DEHP were present in all water and sediment samples. DnBP was abundant in water (53.0–81.2%), while no single dominant congener was found in sediments. The abundances of DiBP were similar to those of DEHP, and DiBP and DEHP collectively accounted for 77.2–97.6% of the Σ16PAEs concentrations. Congener specific analysis confirmed that DnBP was a predictive indicator for the dissolved ∑16 PAEs concentration (correlation coefficient r=0.968, p<0.01), and that DiBP was a predictive indicator for the sediment ∑16 PAEs concentration (r=0.975, p<0.01). As compared to the results for other studies, the urban lakes of Guangzhou were moderately polluted by PAEs.

The influence of humidity on the emission of di-(2-ethylhexyl) phthalate (DEHP) from vinyl flooring in the emission cell “FLEC”

Asthma in children appears to be associated with both phthalate esters and dampness in buildings. An important question is whether the concentrations of phthalate esters correlate with dampness (expressed as relative humidity—RH) in indoor air. The objective was to study the influence of RH on the specific emission rate (SER) of di-(2-ethylhexyl)phthalate (DEHP) from one type of vinyl flooring in the well characterized Field and Laboratory Emission Cell (FLEC). The vinyl flooring with ca. 17% (w/w) DEHP as plasticizer was tested in 6 FLECs at 22 °C. The RH in the 6 FLECs was 10%, 30%, 50% (in triplicate) and 70%. The RH was changed after 248 d in 2 of the 50%-FLECs to 10% and 70%, and to 50% in the 10%-and 70%-FLECs. The data show that the SER of DEHP from vinyl flooring in FLECs during a 1 yr period is independent of the RH. A new physically based emission model for semivolatile organic compounds was found to be consistent with the experimental data and independent of the RH. The model helps to explain the RH results, because it appears that RH does not significantly influence any of the identified controlling mechanisms.

General gynaecology: Association of phthalate esters with endometriosis in Indian women

To evaluate the possible association between phthalate esters (PEs) and the occurrence of endometriosis. Case-control study. Department of Reproductive Medicine, Bhagawan Mahavir Medical Research Centre, Maternal Health and Reproductive Institute and Department of Analytical R&D, Hetero Research Foundation, Hyderabad, Andhra Pradesh, India. Blood samples were collected from 49 infertile women with endometriosis (study group); 38 age-matched women without endometriosis (control group I) but with infertility related to tubal defects, fibroids, polycystic ovaries, idiopathic infertility and pelvic inflammatory diseases diagnosed by laparoscopy and a further group of 21 age-matched women (control group II) with proven fertility and no evidence of endometriosis and other gynaecological disorders during laparoscopic sterilisation. Concentrations of PEs were measured using gas chromatography. Evaluation of PEs concentrations in women with endometriosis compared with women free from the disease. Women with endometriosis showed significantly higher concentrations of di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-n-octyl phthalate (DnOP) and diethyl hexyl phthalate (DEHP) (mean 0.44 [SD 0.41]; 0.66 [SD 0.61]; 3.32 [SD 2.17]; 2.44 [SD 2.17] micrograms/ml) compared with control group I (mean 0.08 [SD 0.14]; 0.12 [SD 0.20]; 0; 0.50 [SD 0.80] micrograms/ml) and control group II (mean 0.15 [SD 0.21]; 0.11 [SD 0.22]; 0; 0.45 [SD 0.68] micrograms/ml). The correlation between the concentrations of PEs and different severity of endometriosis was strong and statistically significant at P < 0.05 for all four compounds (DnBP: r=+0.73, P < 0.0001; BBP: r=+0.78, P < 0.0001; DnOP: r=+0.57, P < 0.0001 and DEHP: r=+0.44, P < 0.0014). This study suggests that PEs may have an aetiological association with endometriosis.

Determination of phthalate ester congeners and mixtures by LC/ESI-MS in sediments and biota of an urbanized marine inlet.

Phthalate esters (PEs) are a group of widely used commercial chemicals consisting of many different congeners. Concentrations of di(2-ethylhexyl) phthalate ester in the parts per million range have been observed in sediments from locations in North America and Europe. However, sediment and biota concentrations of other widely used PEs (i.e., dibutyl phthalate, diisononyl phthalate, and diisodecyl phthalate) are rare and often in doubt because of analytical difficulties. One of the problems is that commercial formulations predominantly consist of PEs with a specific molecular weight but include many isomers within each molecular weight class. Currently there are no analytical methods or required standards to fully separate PEs into the different molecular weight classes corresponding to the formulations from which they originate. Hence, ambient total and mixture-specific PE concentrations do not exist. This study presents a new method based on reversed-phase liquid chromatography/ electrospray ionization mass spectrometry (LC/ESI-MS) for the quantitative determination of individual PEs, including six congeners on the U.S. EPA Priority pollutant list and several commercial PE isomeric mixtures, in complex environmental matrixes. The method is applied to determine the composition of PE concentrations in sediments and fish in an urbanized marine ecosystem. PE fingerprints in sediments show a predominance of high molecular weight PEs and match per capita consumption levels of PEs. Fingerprints in fish tissue show a predominance of low molecular weight PEs and do not match per capita consumption levels. The findings indicate that the higher molecular weight PEs are less biologically available than the lower molecular weight ones.

Role of environmental estrogens in the deterioration of male factor fertility

Objective To evaluate the role of the environmental estrogens polychlorinated biphenyls (PCBs) and phthalate esters (PEs) as potential environmental hazards in the deterioration of semen parameters in infertile men without an obvious etiology. Design Randomized controlled study. Setting Tertiary care referral infertility clinic and academic research center. Patient(s) Twenty-one infertile men with sperm counts <20 million/mL and/or rapid progressive motility <25% and/or <30% normal forms without evidence of an obvious etiology and 32 control men with normal semen analyses and evidence of conception. Intervention(s) Semen and blood samples were obtained as part of the treatment protocol. Main outcome measure(s) Evaluation of semen parameters such as ejaculate volume, sperm count, motility, morphology, vitality, osmoregulatory capacity, sperm chromatin stability, and sperm nuclear DNA integrity. Result(s) PCBs were detected in the seminal plasma of infertile men but not in controls, and the concentration of PEs was significantly higher in infertile men compared with controls. Ejaculate volume, sperm count, progressive motility, normal morphology, and fertilizing capacity were significantly lower in infertile men compared with controls. The highest average PCB and PE concentrations were found in urban fish eaters, followed by rural fish eaters, urban vegetarians, and rural vegetarians. The total motile sperm counts in infertile men were inversely proportional to their xenoestrogen concentrations and were significantly lower than those in the respective controls. Conclusion(s) PCBs and PEs may be instrumental in the deterioration of semen quality in infertile men without an obvious etiology.

Concentration of phthalate esters by polymer-mediated extraction.

Polymer-mediated extraction based on the thermoresponsive precipitation of poly(N-isopropylacrylamide) (PNIPAAm) was successfully applied to the efficient concentration (ca. 100-folds) of phthalate esters in water. With the use of 0.05 g of polymer against a 10 ml sample, the recoveries of di(2-ethylhexyl)phthalate (DEHP) and dibutylphthalate (DBP) were 98 and 82%, respectively. After extraction, μg/l-levels of DEHP and DBP in tap water, physiological saline, and mineral water samples were successfully determined by HPLC with ultra-violet spectrophotometric detection. The relative standard deviation in the determination of 39 μg/l DEHP (n=5) was 3%.

Concentrations of phthalate esters and identification of other additives in PVC children’s toys

This study was intended to provide data on the composition of soft PVC toys, addressing the widest practicable range of chemical additives and including non-phthalate additives. The study also included toys from as many countries as possible, since for many, no data were available. A total of 72 toys were purchased in 17 countries. The majority (64) were PVC or had PVC sections. In almost all the soft PVC toys analysed, phthalates comprised a sizeable proportion (most frequently 10-40%) of the total weight of the toy. The predominant phthalates detected were diisononyl phthalate (DINP) and di(2-ethylhexyl) phthalate (DEHP). Other phthalates identified in high concentrations in some toys include isomeric mixes of diisooctyl phthalate (DIOP) and diisodecyl phthalate (DIDP). The estrogenic chemical nonylphenol was isolated from 13 toys, while 2 toys were found to contain the fungicide Fungitrol 11 (Folpet). 78% of PVC toys contained one or more extractable organic compounds in addition to those reported above.

Broad Spectrum Analysis of Alcohols as Indicator Compounds for Phathalate Plasticizer Contamination in Water and Soil

Abstract The effectiveness of present approaches to the study of the fate and transport of phthalate esters and adipates in surface water and ground water samples is limited by ubiquitous levels of background contamination in the field and the laboratory. An alternative approach is described in which C7-C11 alcohols are used as indicator compounds to circumvent the problems associated with contamination arising from plasticizers at an industrial site. The approach combines information obtained from GC/MS analyses of selected samples with information from a cost-effective pre-screening GC/FID technique. The approach (a) provides broad spectrum data for trend analysis, (b) minimizes the occurrence of false positives, and (c) reduces the cost of analyses required for the delineation of contaminated plumes. For contaminated samples, the concentration of phthalate esters was approximately 3-4 times higher than detectable levels of alcohols. Although the detection limits are 0.1 mg/L and 1 μg/g for water and soil samples, respectively, there is a threshold concentration of phthalate esters of approximately 300 μg/g, below which alcohols were not observed.

Effects of phthalate esters on glucose 6-phosphate dehydrogenase and other enzymes in vitro

Phthalate esters were found to inhibit purified yeast glucose 6-phosphate dehydrogenase (EC 1.1.1.49) but the crude rat liver enzyme was not inhibited. At a concentration of 0.33 μg of enzyme/ml, the concentration of dioctyl phthalate (DOP) that exhibited 50% inhibition was 15.1 μ m. Bovine serum albumin, NADP +, and NADH prevent the enzyme from the inhibition. Bovine serum albumin (2 μg/ml) completely prevented inhibition by 8.5 × 10 −5 m DOP. The inhibition strength depended on the carbon number of the alkyl groups of phthalate esters; the longer the chains of alkyl groups of phthalate esters, the more potent the inhibition. As chain length increased, the n value in modified Hill plots decreased from 4 to 2. Of 13 enzymes tested, only one enzyme was inhibited by low concentrations of phthalate esters and seven enzymes were inhibited by relatively high concentrations of phthalate esters. Pig heart malate dehydrogenase was found to be sensitive to phthalate esters, as was yeast glucose 6-phosphate dehydrogenase.