Diisobutyl Phthalate (DIBP) Final

Project ID

2320

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IRIS

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March 10, 2014, 11:43 a.m.

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Journal Article

Abstract  The hormone insulin-like factor 3 (INSL3) is produced by testicular Leydig cells. Production of INSL3 is dependent on the state of Leydig cell differentiation and is stimulated by the long-term trophic effects of luteinizing hormone. INSL3 is, along with the other major Leydig cell hormone testosterone, essential for testicular descent, which in humans should be completed before birth. The incidence of cryptorchidism (incomplete descent of the testis) may have increased in some developed countries during recent decades. Experimental studies have shown that maternal exposure to endocrine-disrupting chemicals (EDCs), such as phthalates, can result in cryptorchidism among male offspring and that INSL3 production, like steroidogenesis, is susceptible to phthalate exposure. Inhibition of these hormones may occur via a general phthalate-induced impairment of Leydig cell development and maturation. Recent studies have also addressed the sensitivity of human Leydig cells to EDCs, though with varied conclusions.

Journal Article

Abstract  Exposure to endocrine disrupting chemicals such as bisphenol A (BPA) and phthalates is prevalent among children and adolescents, but little is known regarding important sources of exposure at these sensitive life stages. In this study, we measured urinary concentrations of BPA and nine phthalate metabolites in 108 Mexican children aged 8-13years. Associations of age, time of day, and questionnaire items on external environment, water use, and food container use with specific gravity-corrected urinary concentrations were assessed, as were questionnaire items concerning the use of 17 personal care products in the past 48-h. As a secondary aim, third trimester urinary concentrations were measured in 99 mothers of these children, and the relationship between specific gravity-corrected urinary concentrations at these two time points was explored. After adjusting for potential confounding by other personal care product use in the past 48-h, there were statistically significant (p<0.05) positive associations in boys for cologne/perfume use and monoethyl phthalate (MEP), mono(3-carboxypropyl) phthalate (MCPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and in girls for colored cosmetics use and mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), MEHHP, MEOHP, and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), conditioner use and MEP, deodorant use and MEP, and other hair products use and MBP. There was a statistically significant positive trend for the number of personal care products used in the past 48-h and log-MEP in girls. However, there were no statistically significant associations between the analytes and the other questionnaire items and there were no strong correlations between the analytes measured during the third trimester and at 8-13years of age. We demonstrated that personal care product use is associated with exposure to multiple phthalates in children. Due to rapid development, children may be susceptible to impacts from exposure to endocrine disrupting chemicals; thus, reduced or delayed use of certain personal care products among children may be warranted.

Journal Article

Abstract  In a published controlled dosing experiment, a single individual consumed 5mg each of labeled di-n-butyl phthalate (DnBP) and diisobutyl phthalate (DiBP) on separate occasions and tracked metabolites in his blood and urine over 48h. Data from this study were used to structure and calibrate simple pharmacokinetic (PK) models for these two phthalates, which predict urine and blood metabolite concentrations with a given phthalate intake scenario (times and quantities). The calibrated models were applied to a second published experiment in which 5 individuals fasted over the course of a 48-h weekend (bottled water only), and their full urine voids were captured and measured for DnBP and DiBP metabolites. One goal of this model application was to confirm the validity of the calibrated models - their validity would be demonstrated if a profile of intakes could be found which adequately duplicated the metabolite concentrations measured in the urine. A second goal was to study patterns of exposure for this group. It was found that all metabolites could be duplicated very well with individual-specific "best-fit" intake scenarios, with one exception. It appears that the model predicted much lower concentrations of the metabolite, 3carboxy-mono-propylphthalate (MCPP), than were observed in all individuals. Modeled as a metabolite of DnBP, this suggests that DnBP was not the major source of MCPP in the urine. For all 5 individuals, the reconstructed dose profiles of the two phthalates were similar: about 6 small bolus doses per day and an intake of about 0.5μg/kg-day. The intakes did not appear to be associated with diary-reported activities (personal hygiene and medication) of the participants. The modeled frequent intakes suggested one (or both) of two possibilities: ongoing exposures such as an inhalation exposure, or no exposure but rather an ongoing release of body stores of the phthalate metabolites from past exposures.

Journal Article

Abstract  Phthalates are used in industry products, household items, and medical tools as plasticizers. Human exposure to phthalates has raised concern about its toxicity. In the present study, optimization was conducted for the simultaneous analysis of eight kinds of phthalate metabolites using gas chromatography-mass spectrometry (GC-MS): MEP, MiBP, MnBP, MBzP, MiNP, MEHP, MEOHP, and MEHHP. In order to minimize the matrix effect and to do quantitative analysis, isotope dilution and LLE-GC-MS methods were performed. Urine samples were enzymatically hydrolyzed, extracted with a mixture of n-hexane and ethyl ether (8:2; v:v), and subsequently derivatized with trimethylsilylation. All eight kinds of analytes showed clear resolution and high reproducibility in GC-MS results. The method detection limit ranged from 0.05ng/mL to 0.2ng/mL. Calibration curves were found to be linear from 0.2 to 100ng/mL with -(2)>0.992. The relative standard deviation of the intraday precision using water and urine ranged from 2.1% to 16.3%. The analysis was performed with urine samples that were collected from adults residing in the Republic of Korea. The analyzed concentration results were compared according to gender and region. As a result, DEHP metabolites showed the highest detected concentration (75.92μg/g creatinine, 100%), and MiNP, a metabolite of DiNP, showed the lowest detected concentration (0.42μg/g creatinine, 22.5%). On average, female urine (200.76μg/g creatinine) had a higher detected concentration of ∑8 phthalate metabolites than male urine. Samples from rural regions (211.96μg/g creatinine) had higher levels than samples from urban regions.

Journal Article

Abstract  In utero exposure to the phthalate ester plasticizer di-n-hexyl phthalate (DnHP) is known to affect the development of the male reproductive system and induce alterations in androgen-dependent tissues of male rat offspring. Male reproductive malformations produced by several phthalates have been causally linked to decreased testosterone production during the gestational period. This study was designed to evaluate the dose-response relationship for the effects of DnHP on the synthesis and production of testosterone in the fetal rat testis. Pregnant Sprague-Dawley rats were administered the vehicle (olive oil) and either DnHP (5 to 625 mg kg(-1) per day) or diethylhexyl phthalate (DEHP) (50 or 625 mg kg(-1) per day), by gavage, from gestation day (GD) 12 to19. Fetal testes were assessed on GD 19. DnHP reduced ex vivo testosterone production and down-regulated the expression of several genes required for cholesterol transport and steroid synthesis (i.e. SR-B1, StAR, P450scc, 3βHSD and P450c17). These inhibitions were dose dependent. A no-effect level was established at 5 mg kg(-1) per day and a lowest-effect level at 20 mg kg(-1) per day. mRNA levels of SR-B1, StAR, P450scc and 3βHSD were not similarly decreased in the adrenals. In conclusion, DnHP shares the same mode of action as DEHP in disrupting fetal testicular androgen synthesis. Alterations in testosterone production and in key steroidogenic gene expressions were apparent at lower doses than those causing postnatal reproductive malformations after gestational exposure during the critical period of male sexual differentiation. This suggests that they can be considered early biomarkers of DnHP-induced fetal testicular effects in rats.

Journal Article

Abstract  Human exposure to chemicals commonly encountered in our environment, like phthalates, is routinely assessed through urinary measurement of their metabolites. A particular attention is given to the specific population groups, such as obese, for which the dietary intake of environmental chemicals is higher. To evaluate the exposure to phthalates, nine phthalate metabolites (PMs) were analyzed in urine collected from obese individuals and a control population. Obese individuals lost weight through either bariatric surgery or a conservative weight loss program with dietary and lifestyle counseling. Urine samples were also collected from the obese individuals after 3, 6 and 12months of weight loss. Individual daily intakes of the corresponding phthalate diesters were estimated based on the urinary PM concentrations. A high variability was recorded for the levels of each PM in both obese and control urine samples showing the exposure to high levels of PMs in specific subgroups. The most important PM metabolite as percentage contribution to the total PM levels was mono-ethyl phthalate followed by the metabolites of di-butyl phthalate and di 2-ethyl-hexyl phthalate (DEHP). No differences in the PM levels and profiles between obese entering the program and controls were observed. Although paralleled by a significant decrease of their weight, an increase in the urinary PM levels after 3 to 6months loss was seen. Constant figures for the estimated phthalates daily intake were observed over the studied period, suggesting that besides food consumption, other human exposure sources to phthalates (e.g. air, dust) might be also important. The weight loss treatment method followed by obese individuals influenced the correlations between PM levels, suggesting a change of the intake sources with time. Except for few gender differences recorded between the urinary DEHP metabolites correlations, no other differences were observed for the urinary PM levels as a function of age, body mass index or waist circumference. Linear regression analysis showed almost no significance of the relationship between measured urinary PMs and serum free thyroxine, thyroid-stimulating hormone (TSH) for all obese individuals participating to the study, while for the control samples, several PMs were significantly associated with the serum TSH levels.

Journal Article

Abstract  The pathway through which retinol (vitamin A) is converted to its active metabolite, all-trans-retinoic acid (atRA), and subsequent receptor-mediated regulation of gene transcription by atRA is essential for all mammal life stages. This pathway is required for normal embryonic development and maintenance of cellular phenotype in adult organisms; chemicals that cause even minor interference with its normal function are potential developmental and adult toxicants. A short-term (24 h) in vitro mode-of-action screen for detecting chemicals that disrupt this essential pathway is described. It uses the mouse pluripotent P19 stem cell in a 96-well format, RT-qPCR gene-expression assay that does not require RNA purification to detect chemicals that interfere with retinol-induced Hoxa1 gene expression, a target of retinol signaling in mammals. A total of 21 chemicals were screened at a single 45 μM concentration. Four chemicals known to disrupt the pathway in the rodent embryo (citral, disulfiram, and two rodent teratogens, nitrofen and bisdiamine) all significantly inhibited Hoxa1 upregulation by retinol. An additional four of seven chemicals with varying degrees of structural similarity to known disruptors or to the retinoid side chain, but not previously known to disrupt the pathway, were positive in the screen. The xenoestrogens, diethylstilbestrol, bisphenol A, 4-n-nonylphenol, and genistein and the phthalate esters, dibutyl phthalate and dipentyl phthalate, but not diethylhexyl phthalate, also significantly disrupted the pathway. Of the 21 chemicals tested, diethylstilbestrol was the only chemical that showed evidence in the MTT assay that cytotoxicity may have contributed to disruption of the pathway. Birth Defects Res (Part B) 98:276-282, 2013. © 2013 Wiley Periodicals, Inc.

Journal Article

Abstract  Phthalate esters (PAEs), a group of emerging organic contaminants, have become a serious issue arousing much attention for their ubiquitous presence and hazardous impact on the environment. This study provides the first data on distribution of PAEs in the sediments in the Qiantang River, Zhejiang Province, China, and the inference with urbanization and river flow regime. PAEs were detected in all 23 sediment samples analyzed, and the total concentrations of their 16 congeners in sediments ranged from 0.59 to 6.74μg/g dry weight (dw), with the geometric mean value of 2.03μg/g dw. Of the 16 PAE congeners, di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP) were present in all sediment samples. The PAEs concentrations in urban regions were higher than those in rural regions because of higher discharge of PAEs from plastic materials in urbanized areas. Concentrations of PAEs were positively correlated with sediment organic matter (fOM) and negatively correlated with logistic value of annual average flow volume at sample sites. River flow regime modified by man-made dams significantly affected the distribution of PAEs. Analysis of congener composition of PAEs indicated that the DEHP was predominant congener in the Qiantang River. The normalized concentration of DEHP exceeded recommended environmental risk limit (ERL).

Journal Article

Abstract  PURPOSE OF REVIEW: Phthalates are multifunctional chemicals used in personal care products, medications, and plastics. We reviewed the epidemiological literature examining the relationship between early life phthalate exposure and pediatric health outcomes.

RECENT FINDINGS: Five studies from Asia, Europe, and the United States suggest that childhood exposure to di-2-ethylhexyl phthalate (DEHP) and butylbenzyl phthalate (BBzP) may increase the risk of allergic diseases including asthma and eczema. Six studies from four different prospective cohorts report that gestational BBzP, DEHP, di-butyl phthalate (DBP), and di-ethyl phthalate (DEP) exposures are associated with alterations in infant/toddler physical development as well as parent-reported externalizing, internalizing, and autistic-like child behavior. However, there are inconsistencies related to the specific phthalates and behavioral domains. Two small studies report shorter anogenital distance among male infants with higher gestational phthalate exposure.

SUMMARY: Several epidemiological studies suggest fetal and childhood exposure to some phthalates may perturb normal development, with several studies consistently reporting increased risk of allergic diseases with DEHP and BBzP exposure. Although anticipatory guidance is not evidence-based at this time, providers can counsel concerned patients to reduce phthalate exposures in order to protect the developing fetus and child from potential adverse health outcomes.

Journal Article

Abstract  Phthalate diesters, widely used in flexible plastics and consumer products, have become prevalent contaminants in the environment. Human exposure is ubiquitous and higher phthalate metabolite concentrations documented in patients using medications with phthalate-containing slow release capsules raises concerns for potential health effects. Furthermore, animal studies suggest that phthalate exposure can modulate circulating hormone concentrations and thus may be able to adversely affect reproductive physiology and the development of estrogen sensitive target tissues. Therefore, we conducted a systematic review of the epidemiological and experimental animal literature examining the relationship between phthalate exposure and adverse female reproductive health outcomes. The epidemiological literature is sparse for most outcomes studied and plagued by small sample size, methodological weaknesses, and thus fails to support a conclusion of an adverse effect of phthalate exposure. Despite a paucity of experimental animal studies for several phthalates, we conclude that there is sufficient evidence to suggest that phthalates are reproductive toxicants. However, we note that the concentrations needed to induce adverse health effects are high compared to the concentrations measured in contemporary human biomonitoring studies. We propose that the current patchwork of studies, potential for additive effects and evidence of adverse effects of phthalate exposure in subsequent generations and at lower concentrations than in the parental generation support the need for further study.

Journal Article

Abstract  We conducted an epidemiologic study to test the hypothesis that women who smoke have reduced fertility. Data on smoking history and number of noncontracepting cycles until conception were collected from 678 pregnant women. Thirty-eight percent of nonsmokers conceived in their first cycle compared with 28% of smokers. Smokers were 3.4 times more likely to have taken greater than a year to conceive compared with nonsmokers. After adjusting for potential confounding variables by Cox proportional hazards regression, fertility of smokers was estimated to be 72% of the fertility of nonsmokers. Heavy smokers experienced lower fertility than did light smokers (57% and 75% of the pregnancy rate of nonsmokers, respectively). Fertility was not affected by the husband's smoking. These data provide evidence that reduced fertility should be added to the growing list of reproductive hazards of cigarette smoking.

DOI
Journal Article

Abstract  A migration prediction model of residual contaminants from food packaging paper was established on the basis of one-dimensioned Fick's diffusion theory, and analytical solutions were obtained by inducing paper porosity and the adsorption quantity of pollutants. In addition, the migration of the six contaminants, namely styrene, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate and bisphenol A in three kinds of food packaging paper(Kraft, white cardboard and imitation parchment) into different food stimulants was studied. In this study, the diffusion coefficient and the partition coefficient of these six contaminants in those papers were measured by experiments, and the experimental migration data and calculated values based on the model were analyzed. The results show that paper porosity affects the migration of contaminants so significantly that it is necessary to set it as a parameter in the analysis model. The experiment results agreed with the theoretical prediction values when the temperature was set approximately at 25 degrees C. Copyright (c) 2012 John Wiley & Sons, Ltd.

DOI
Journal Article

Abstract  Several diesters were developed as internal donors of the Ziegler-Natta catalysts, the molecular structures of the diesters are close to that of diisobutyl phthalate. Furthermore,the effects on the performance of the catalysts were studied. Results showed that the catalysts prepared by different preparation processes have the same MgCl2 lattice style (delta). The changing of diesters have notable influences on the porosity and the specific surface areas of the catalysts, and the polymerization performance and the PP isotactic index vary with different addition ways of the diesters in the preparation processes of the catalysts. When the internal donor is diisobutyl cis-cyclohexane dicarboxylate, the polymerization activity of the catalyst and the PP index are the highest,reaching the level of the industry catalyst. In the polymerization of CAT-2A, using CMMS as the external electron donor, the ratio of Si to Ti is 10 and the ratio of Al to Ti is 100, the polymerization activity and PP isotactic index reach the highest level.

Journal Article

Abstract  BACKGROUND: There is concern over potential neurobehavioral effects of prenatal phthalate exposures, but available data are inconsistent.

OBJECTIVES: To examine associations between prenatal urinary concentrations of phthalate metabolites and neurobehavioral scores among children.

METHODS: We measured phthalate metabolite concentrations in urine samples from 153 pregnant participants in the Study for Future Families, a multicenter cohort study. Mothers completed the Child Behavior Checklist when the children were 6-10 years of age. We estimated overall and sex-specific associations between phthalate concentrations and behavior using adjusted multiple regression interaction models.

RESULTS: In boys concentrations of mono-isobutyl phthalate were associated with higher scores for inattention (β = 0.27; 95% CI: 0.04, 0.50), rule-breaking behavior (β = 0.20; 95% CI: 0.01, 0.38), aggression (β = 0.34; 95% CI: 0.09, 0.59), and conduct problems (β = 0.39; 95% CI: 0.20, 0.58), while the molar sum of di-(2-ethylhexyl) phthalate metabolites was associated with higher scores for somatic problems (β = 0.15; 95% CI: 0.03, 0.28). Higher monobenzyl phthalate concentrations were associated with higher scores for oppositional behavior (β = 0.16; 95% CI: 0.01, 0.32) and conduct problems (β = 0.21; 95% CI: 0.06, 0.37) in boys, but with reduced anxiety scores in girls (β = -0.20; 95% CI: -0.39, -0.01). In general, the associations reported above were close to the null among girls. Model coefficients represent the difference in the square-root transformed outcome score associated with a 1-unit increase in log-transformed metabolites.

CONCLUSIONS: Our results suggest associations between exposure to certain phthalates in late pregnancy and behavioral problems in boys. Given the few studies on this topic and methodological and population differences among studies, additional research is warranted.

Journal Article

Abstract  A GC/MS method was developed for the identification and quantification of 14 phthalates: 8 phthalates classified H360 (DBP, DEHP, BBP, DMEP, DnPP, DiPP, DPP and DiBP), 3 phthalates proposed to be forbidden in medical devices (DnOP, DiNP and DiDP) and 3 other phthalates none regulated (DMP, DCHP and DEP) which may interfere with hormone function. In order to identify and quantify other plasticizers that are commonly used in PVC medical devices such as DEHP substitute, 5 non-phthalate plasticizers (ATBC, DEHA, DEHT, TOTM, and DINCH) were included in this study. Analyses are carried out on a GC/MS system with electron impact ionization mode (EI). The separation of plasticizers is obtained on a cross-linked 5%-phenyl/95%-dimethylpolysiloxane capillary column 30m×0.25mm (i.d.)×0.25μm film thickness using a gradient temperature. Compounds quantification is performed by external calibration using an internal standard. Validation elements on standard solutions were determined using the ISO 12787 standard approach. Plasticizers are extracted from PVC medical devices using THF for dissolving the PVC part of the sample followed by precipitation of the PVC by addition of ethanol. The supernatant is injected into a GC/MS system after dilution in ethanol. Different validation elements, including extraction recoveries for all compounds or for DEHP a cross-validation of the extraction process using the European pharmacopoeia monograph 3.1.14 as reference method, are discussed. Results obtained on 61 medical devices in PVC and 12 raw materials used as plasticizers are given.

Journal Article

Abstract  Partition and diffusion experiments were carried out with paper and board samples coated with different biopolymers. The aim was to evaluate the physicochemical behaviour and barrier properties of bio-coatings against migration of typical contaminants from recycled paper packaging. Focus was directed towards water-based, renewable biopolymers, such as modified starches (cationic starch and cationic waxy starch), plant and animal proteins (gluten and gelatine), poured onto paper with an automatic applicator. Additionally, a comparison with polyethylene-laminated paper was performed. Microstructural observations of the bio-coated paper allowed the characterisation of samples. From the partitioning studies, considerable differences in the adsorption behaviour of the selected contaminants between bio-coated or uncoated paper and air were highlighted. For both the polar and non-polar compounds considered (benzophenone and diisobutyl phthalate, respectively), the lowest values of partition coefficients were found when paper was bio-coated, making it evident that biopolymers acted as chemical/physical barriers towards these contaminants. These findings are discussed considering the characteristics of the tested biopolymers. Diffusion studies into the solid food simulant poly 2,6-diphenyl-p-phenylene oxide, also known as Tenax(®), confirmed that all the tested biopolymers slowed down migration. The Weibull kinetic model was fitted to the experimental data to compare migration from paper and bio-coated paper. Values found for β, an index determining the pattern of curvature, ranged from 1.1 to 1.7 for uncoated and polyethylene paper, whereas for bio-coated papers they ranged from 2.2 to 4.9, corresponding to the presence of an evident lag phase due to barrier properties of the tested bio-coatings.

Journal Article

Abstract  in their 10th or 11th years, while others who are equally healthy may not experience menarche until they 'are 14, 15, or even older. Menarche is, however, only a single event in the combination of physical changes which constitute puberty. The adolescent growth spurt, the development of the breasts, and the growth of the pubic hair occur more or less concurrently, and take, on the average, about 3 years from beginning to completion, with menarche occurring usually in the latter half of this period (Tanner, 1962). At present we lack detailed information about the rate at which girls progress through the stages of puberty and about the relation of one event to another. Only longitudinal studies (i.e. studies in which the same individuals are examined repeatedly over a period of time) can provide this information, which would be helpful both to the clinician in distinguishing the normal from the abnormal, and to the neuro-endocrinologist in constructing hypotheses about the mechanisms by which puberty is controlled. Present knowledge is based on studies carried out on small numbers of children in the United States a generation ago, together with some German studies of a similar period (for literature see Tanner, 1962).

Technical Report

Abstract  The Fourth National Report on Human Exposure to Environmental Chemicals, Updated Tables, September 2013 provides nationally representative biomonitoring data that has become available since the publication of the Fourth National Report on Human Exposure to Environmental Chemicals, 2009. The Updated Tables, September 2013 includes all the updates previously provided in Updated Tables, July 2010 through Updated Tables, March 2013. The Updated Tables, September 2013 present data for 91 chemicals measured in serum pooled samples that have not been reported in any previous Updated Tables. Since publication of the Fourth Report, 2009, 201 chemicals have updated tables and 49 chemicals have been added, for a total of 250 chemicals presented in these Updated Tables.

Journal Article

Abstract  OBJECTIVE: The purpose of this study was to evaluate the accuracy of algorithms for the assignment of gestational age with the use of the last menstrual period and early ultrasound information. STUDY DESIGN: Gestational age estimates that are based on last menstrual period, ultrasound scanning, or their combination were compared among women who attended prenatal care clinics in central North Carolina (n = 3655) by an evaluation of digit preference in the last menstrual period dates and a comparison of mean gestational age, preterm and postterm categories with the use of K statistics, difference between actual and expected delivery date, and birth weight among subgroups with discrepant assignments. RESULTS: Last menstrual period reports show digit preference, assign gestation 2.8 days longer on average than ultrasound scanning, yield substantially more postterm births (12.1% vs 3.4%), and predict delivery among term births less accurately. Misclassification of births as postterm was more common in younger women, those of nonoptimal prepregnancy body weight, cigarette smokers, and women who reported last menstrual period using preferred dates of the month. CONCLUSION: Last menstrual period estimates of the duration of gestation are subject to both random error and a systematic tendency to overstate the duration of gestation, most likely because of delayed ovulation.

Journal Article

Abstract  A very simple, fast and environmentally friendly sample extraction method was proposed for the analysis of phthalate esters (PAEs, di-isobutyl phthalate (DIBP), dibutylphthalate (DBP), butylbenzylphthalate (BBP) and bis(2-ethylhexyl)phthalate (DEHP)) in alcoholic beverages by using conventional ionic liquid dispersive liquid-liquid microextraction. The samples were extracted by 160μL 1-octyl-3-methylimidazolium hexafluorophosphate in the presence of appropriate amount of ethanol and 10% (w/v) sodium chloride solution; the enriched analytes in sedimented phases were analyzed by high performance liquid chromatography-diode array detector (HPLC-DAD). Under the optimum conditions, a satisfactory linearity (in the range of 0.02-1μgmL(-1) for white spirits and 0.01-0.5μgmL(-1) for red wines with the correlation coefficients (r) varying from 0.9983 to 1), acceptable recovery rates (88.5-103.5% for white spirits and 91.6-104.6% for red wines), good repeatability (RSD≤8.0%) and low detection limits (3.1-4.2ngmL(-1) for white spirits and 1.5-2.2ngmL(-1) for red wines) were obtained. The developed method was successfully applied for the determination of the four PAEs in 30 white spirits and 11 red wines collected locally, and the DBP content in 63% (19:30) white spirits exceeded the specific migration limit of 0.3mgkg(-1) established by international regulation.

Journal Article

Abstract  The toxicity of phthalates is an important concern in the fields of environmental health and toxicology. Dermal exposure via skin care products, soil, and dust is a main route for phthalate delivery. We had explored the effect of topically-applied phthalates on skin absorption and toxicity. Immunohistology, functional proteomics, and Western blotting were employed as methodologies for validating phthalate toxicity. Among 5 phthalates tested, di(2-ethylhexyl)phthalate (DEHP) showed the highest skin reservoir. Only diethyl phthalate (DEP) and dibutyl phthalate (DBP) could penetrate across skin. Strat-M(®) membrane could be used as permeation barrier for predicting phthalate penetration through skin. The accumulation of DEHP in hair follicles was ∼15nmol/cm(2), which was significantly greater than DBP and DEP. DBP induced apoptosis of keratinocytes and fibroblasts via caspase-3 activation. This result was confirmed by downregulation of 14-3-3 and immunohistology of TUNEL. On the other hand, the HSP60 overexpression and immunostaining of COX-2 suggested inflammatory response induced by DEP and DEHP. The proteomic profiling verified the role of calcium homeostasis on skin inflammation. Some proteins investigated in this study can be sensitive biomarkers for dermal toxicity of phthalates. These included HSPs, 14-3-3, and cytokeratin. This work provided novel platforms for examining phthalate toxicity on skin.

Journal Article

Abstract  Chlorophorus caragana is an important wood-boring pest that infests Caragana korshinskii. The larvae bore into the stems to the point of hollowing them out, causing the whole tree to wither and even die. To control these infestations, volatile compounds were collected from C. korshinskii and used in electroantennography to ascertain which plant semiochemicals could be used to trap adult C. caragana in the field. Isophorone, cis-3-hexen-1-ol, 3-pentanone, dibutyl phthalate, and diisobutyl phthalate were the main volatile compounds produced by C. korshinskii. These compounds induced dose-dependent electrophysiological responses in the antennae of adult C. caragana to some degree. Accordingly, 58 different compound mixtures were tested in field trapping experiments over two consecutive years. Isophorone was most attractive to adult insects. In the field, the best traps were funnel-shaped ones hanging at a height of 1 m. The trapping efficiency was 63.8%. Adult beetles appear between mid June and late August, with an eclosion peak in mid July. The prototype trapping system developed could be used as a tool to monitor and control C. caragana adults.

Journal Article

Abstract  Concentrations of nine phthalate diesters in 24-h airborne PM2.5 and PM10 were determined from October 2011 to August 2012 in a suburban area in Shanghai, China. Dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), di-iso-butyl phthalate (DIBP), benzyl butyl phthalate (BzBP), and di(2-ethylhexyl) phthalate (DEHP) were frequently detected in airborne particulate matter at sum concentrations of these six compounds ranging from 13.3 to 186ng/m(3), with an average value of 59.8ng/m(3) in PM2.5, and from 10.1 to 445ng/m(3), with an average value of 132ng/m(3) in PM10. DEHP, DBP, and DIBP were the major phthalate diesters found in PM samples. DEHP was found predominantly in coarse (size fraction of between PM2.5 and PM10) particles, whereas DMP, DEP, DBP, DIBP, and BzBP were found predominantly in fine (PM2.5) particles. The concentrations of phthalates in PM during warm months (207ng/m(3) for PM10 and 71.9ng/m(3) for PM2.5, on average) were significantly higher than those during cold months (76.9ng/m(3) for PM10 and 50.4ng/m(3) for PM2.5). Significant positive correlations were found between concentrations of total phthalates, DEHP, and BzBP, with the total mass and organic carbon content of PM. Based on the concentrations of DEHP, incremental lifetime cancer risks (ILCR) from inhalation exposure were estimated using a Monte Carlo simulation. Although the 95% probabilities for the ILCR values for the general population were below the U.S. Environmental Protection Agency (EPA) threshold of 10(-6), our result is an underestimate of the actual health risk because we only considered the outdoor inhalation exposure to DEHP in this study.

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