OBJECTIVES: Although phthalates like dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) are commonly used as plasticizers and their metabolites are especially suspected of reproductive toxicity, little is known about occupational exposure to those phthalates. The aim of this study was to assess the utility of measuring the metabolite concentrations of DBP and DEHP in serum and urine samples as an indicator of occupational exposure to those phthalates. METHODS: Phthalate metabolites were analyzed by using column-switching high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS). RESULTS: We detected phthalate metabolites in serum and urine matrices at approximately 10-fold lower than the limit of detection of those metabolites in the same matrix by LC-MS/MS without column switching, which was sufficient to evaluate concentrations of phthalate metabolites for industrial workers and the general population. CONCLUSION: The accuracy and precision of the analytical method indicate that urinary metabolite determination can be a more acceptable biomarker for studying phthalate exposure and adverse health outcomes.
Biomarkers ; Chromatography, Liquid ; Dibutyl Phthalate ; Diethylhexyl Phthalate ; Humans ; Limit of Detection ; Occupational Exposure ; Phthalic Acids ; Plasticizers ; Plastics ; Tandem Mass Spectrometry

OBJECTIVETo understand the dietary consumption of residents in Xiamen and the content of phthalic acid esters (PAEs) in food, and to assess the plasticizer exposure risk of diet in Xiamen.

METHODSThe survey was conducted by stratified cluster random sampling method in Xiamen from September to October in 2010. According to the Xiamen administrative division, six neighborhood communities were selected as sampling units, then 25 families were randomly chosen from each sampling units.From the above 150 families, the permanent residents over the age of six were permitted to our study. The survey included 495 residents totally. These participants' information, such as basic personal information, physical activity levels, meal frequency and the average consumption of 33 kinds of food in 13 categories were collected using questionnaires. Thirteen categories included cereal and tubers, beans, vegetables, fungi and algae, fruits, dairy products, meat, seafood, eggs, snacks, beverages, cooking oil and spices. The height and weight of residents were measured and the average daily dietary intake was calculated. Thirty-three kinds of food in 13 categories were collected in supermarkets in Xiamen. According to the annual sales ranking, the top three-five brands of each kinds of food were selected and numbered, then two or three brands were chosen by random number table method from them; three completely individual packed samples in the same batch of each brand were detected; 243 samples were included in our study.100-500 g solid samples or 100-500 ml liquid samples were collected. The content of diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) in food were detected by liquid chromatography mass spectrometry, which expressed by median (minimum-maximum). The exposure dose, contribution rate and risk index of PAEs were calculated by point estimation method.

RESULTSAccording to the average daily dietary intake of residents in Xiamen, the top three ones in 13 categories of food were cereal and tubers (337.16 g/d, 18.21%), vegetables (309.12 g/d, 16.69%) and fruits (213.20 g/d, 11.51%). The content of DEP, DBP or DEHP among different categories of food was significantly different (χ² values were 58.05, 50.19 and 102.10, P < 0.01). Among 13 categories of food, seafood contained the most DEP (0.090 (0.000-0.324)mg/kg); cooking oil had the most DBP (0.700(0.000-2.980) mg/kg) and DEHP (5.115(0.000-24.160) mg/kg). DEP, DBP and DEHP exposure(0.19, 4.20, 18.10 µg × kg⁻¹ ×d ⁻¹)in dietary food in Xiamen were less than the reference dose(RfD) (800, 100, 20 µg × kg⁻¹ × d⁻¹) proposed by the United States Environmental Protection Agency (EPA), and the risk indexes were 0.02%, 4.20% and 90.50%, respectively. Among 13 categories of foods, seafood was the main source of DEP dietary exposure. The exposure dose and contribution rate of DEP in seafood were 0.18 µg × kg⁻¹ × d⁻¹ and 94.74%, respectively.Vegetables were the main source of DBP and DEHP dietary exposure. The exposure dose and contribution rate of DBP and DEHP were 1.48 µg × kg⁻¹ × d⁻¹, 35.24% and 6.07 µg × kg⁻¹ × d⁻¹, 33.54%, respectively.

CONCLUSIONThe food consumed by residents in Xiamen was overall in a safe state, but to some extent, there still exists DEHP exposure risk in foods.

China ; Dibutyl Phthalate ; Diet ; Diethylhexyl Phthalate ; Food Contamination ; Humans ; Phthalic Acids ; Plasticizers ; Risk Assessment ; Seafood ; United States ; Vegetables

OBJECTIVES: This study assessed the health risks for children exposed to phthalate through several pathways including house dust, surface wipes and hand wipes in child facilities and indoor playgrounds. METHODS: The indoor samples were collected from various children's facilities (40 playrooms, 42 daycare centers, 44 kindergartens, and 42 indoor-playgrounds) in both summer (Jul-Sep, 2007) and winter (Jan-Feb, 2008). Hazard index (HI) was estimated for the non-carcinogens and the examined phthalates were diethylhexyl phthalate (DEHP), diethyl phthalate (DEP), dibutyl-n-butyl phthalate (DnBP), and butylbenzyl phthalate (BBzP). The present study examined these four kinds of samples, i.e., indoor dust, surface wipes of product and hand wipes. RESULTS: Among the phthalates, the detection rates of DEHP were 98% in dust samples, 100% in surface wipe samples, and 95% in hand wipe samples. In this study, phthalate levels obtained from floor dust, product surface and children's hand wipe samples were similar to or slightly less compared to previous studies. The 50th and 95th percentile value of child-sensitive materials did not exceed 1 (HI) for all subjects in all facilities. CONCLUSIONS: For DEHP, DnBP and BBzP their detection rates through multi-routes were high and their risk based on health risk assessment was also observed to be acceptable. This study suggested that ingestion and dermal exposure could be the most important pathway of phthalates besides digestion through food.
2,4-Dinitrophenol ; Child ; Diethylhexyl Phthalate ; Digestion ; Dust ; Eating ; Floors and Floorcoverings ; Hand ; Humans ; Phthalic Acids ; Risk Assessment

Cell Line, Tumor ; Cell Movement ; Diethylhexyl Phthalate/toxicity* ; Epithelial-Mesenchymal Transition ; Humans ; Neoplasm Invasiveness ; Phthalic Acids

OBJECTIVE: To investigate the effects of Shoutai pills (a traditional Chinese medicinal preparation) on immune functions and oxidative stress in pregnant rats exposed to di(2-ethylhexyl) phthalate (DEHP). METHODS: Thirty-six mature female SD rats were randomly divided into 3 groups (=12). After pregnancy was confirmed, the rats were given 10 mL/kg corn oil +10 mL/kg saline (control group), 500 mg/kg DEHP+10 mL/kg saline (model group), and 500 mg/kg DEHP+10 mL/kg Shoutai pills (treatment group). At 19 days of gestation, the rats were sacrificed and the fetal rats were weighed and the numbers of live and stillborn fetal rats were recorded. Serum levels of interleukin-6 (IL-6), interleukin-2 (IL-2), tumor necrosis factor-ɑ (TNF-ɑ), estradiol (E2) and progesterone (P) levels were detected. The appearance, color and quality of the placenta in each group were recorded, and the placental tissues were examined pathologically. The total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH- Px), catalase (CAT), reactive oxygen species (ROS) and malondialdehyde (MDA) in the placental tissues were measured. RESULTS: Compared with the control group, the rats with DEHP exposure showed slow weight gain in the middle and late gestation period and significantly lower fetal weight ( < 0.05) with lowered serum levels of IL-2, IL-6 and TNF-ɑ, increased estradiol level ( < 0.05), decreased placental T-AOC, GSH-Px, SOD and CAT levels, and increased ROS and MDA levels ( < 0.01). Compared with the model group, the rats treated with Shoutai pills had significantly increased weight gain in mid and late pregnancy and greater fetal weight ( < 0.05) with significantly increased serum IL-2 and IL-6 levels, decreased estradiol level ( < 0.05), slightly increased TNF-ɑ expression (> 0.05), increased placenta T-AOC, GSH- Px and CAT levels, decreased MDA level ( < 0.05), and slightly increased SOD and decreased ROS levels (>0.05). No significant difference was found in progesterone levels among the groups (>0.05). HE staining showed that the trophoblast in the placental tissue sponge in the model group was loose and irregular with numerous vacuoles. In the treatment group, the structure of the placenta remained intact with clearly visible labyrinth zone, sponge trophoblast and giant cell trophoblast, and the cell distribution in each layer was better than that in the model group. CONCLUSIONS Shoutai pills can regulate the immune function of DEHP-exposed pregnant rats possibly by antagonizing the estrogenlike effect of DEHP and regulating serum immune factors; Shoutai pills can also reduce placental tissue damage and improve pregnancy outcome by correcting DEHP-induced imbalance of oxidative stress in the placental tissues.
Animals ; Diethylhexyl Phthalate ; Female ; Oxidative Stress ; Phthalic Acids ; Pregnancy ; Rats ; Rats, Sprague-Dawley

OBJECTIVES: Maintaining the constant exposure to hydrophobic organic compouds in acute toxicity tests is one of the most difficult issues in the evaluation of their toxicity and corresponding risks. Passive dosing is an emerging tool to keep constant aqueous concentration because of the overwhelming mass loaded in the dosing phase. The primary objectives of this study were to develop the constant exposure condition for an acute mortality test and to compare the performance of the passive dosing method with the conventional spiking with co-solvent. METHODS: A custom cut polydimethylsiloxane (PDMS) tubing loaded with benzyl butyl phthalate (BBP) was placed in each well of a 24-well plate containing assay medium. The rate of the release of BBP from PDMS was evaluated by measuring the change in the concentration of BBP in the assay medium. The efficiency of maintaining constant exposure condition was also evaluated using a simple two-compartment mass transport model employing a film-diffusion theory. An acute mortality test using 10 C. elegans in each well was conducted for the evaluation of the validity of passive dosing and the comparative evaluation of the passive dosing method and the conventional spiking method. RESULTS: Free concentration in the assay medium reached 95% steady state value within 2.2 hours without test organisms, indicating that this passive dosing method is useful for an acute toxicity test in 24 hours. The measured concentration after the mortality test agreed well with the estimated values from partitioning between PDMS and the assay medium. However, the difference between the nominal and the free concentration became larger as the spiked concentration approached water solubility, indicating the instability of the conventional spiking with a co-solvent. CONCLUSIONS: The results in this study support that passive dosing provides a stable exposure condition for an acute toxicity test. Thus, it is likely that more reliable toxicity assessment can be made for hydrophobic chemicals using passive dosing.
Benzophenones ; Biological Availability ; Boronic Acids ; Caenorhabditis ; Caenorhabditis elegans ; Dibutyl Phthalate ; Dimethylpolysiloxanes ; Phthalic Acids ; Solubility ; Toxicity Tests, Acute

PURPOSE: Environmental endocrine disruptors may affect the endocrine system or sexual development in children. Several recent studies have focused on indoor and dietary pollutants such as di-(2-ethylhexyl) phthalate (DEHP), which is used as a plastic softener, and bisphenol A, which is used in food-packaging materials. Despite the accumulation of data and the substantial arguments implicatinf these pollutants in endocrinal disorders, no clear evidence has been established yet. Thus, we assessed the serum levels of DEHP and bisphenol A in patients diagnosed with idiopathic central precocious puberty (CPP) to estimate the possible environmental hazards associated with increasing number of cases of precocious puberty. METHODS: The study included 30 patients (29 girls and 1 boy) with idiopathic CPP and 30 normal control children who visited the pediatric endocrinology clinic. CPP was diagnosed on the basis of clinical & hormonal tests, including the gonadotropin-releasing hormone-stimulation test. The serum DEHP and bisphenol A levels were analyzed by gas chromatography/mass spectrometry. RESULTS: The mean chronological ages (CA) in the idiopathic CPP and control groups were similar (8.6+/-0.9 vs. 7.8+/-1.1 years). However, the overall growth stage in the CPP group was advanced. The CPP group had a significantly higher height SDS (1.3+/-1.0 vs. -0.4+/-1.1, P<0.005) and weight SDS (1.3+/-1.3 vs. -0.2+/-1.3, P<0.005) than the control group. Bone age was significantly more advanced in the CPP group than in the control group (BA-CA:14.6+/-9.4 months vs. 0.8+/-15.3 months, P<0.005). While the serum bisphenol A levels were not significantly different between the groups (11.2+/-10.3 vs.16.2+/-12.5 ng/mL), the DEHP levels were significantly higher in the CPP group than in the control group (159.01+/-92.78 vs. 103.55+/-92.98 ng/mL, P<0.05). CONCLUSION: This study suggests that DEHP, one of most commonly used plasticizers, may be an etiologic factor for precocious puberty.
Benzhydryl Compounds ; Child ; Diethylhexyl Phthalate ; Endocrine Disruptors ; Endocrine System ; Endocrinology ; Hazardous Substances ; Humans ; Phenols ; Phthalic Acids ; Piperazines ; Plasticizers ; Plastics ; Puberty, Precocious ; Sexual Development

OBJECTIVETo study the association between phthalate esters (PAEs) metabolites in maternal urine and 11beta-hydroxysteroid dehydrogenase type 2 (11β-HSD2 ) enzyme activity, explore the possible mechanism of PAEs effect on fetal development.

METHODSAll of 33 cases of intrauterine growth retardation (IUGR) newborn were selected by random sampling in 2012. And 33 cases of normal control newborn were enrolled, use high performance liquid chromatography-tandem mass spectrometry method was used to detect 4 kinds of phthalate esters (PAEs) metabolites in maternal urine: mono-n-butyl phthalate ester (MBP), mono (2-ethylhexyl) phthalate (MEHP), mono (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) and three kinds of cortisol corticosterone metabolites, tetrahydrocortisol (THF), allo-tetrahydrocortisol (allo-THF), tetrahydrocortisone (THE), and analyze the association between phthalate esters (PAEs) metabolites in maternal urine and 11β-HSD2 enzyme activity.

RESULTSMBP, MEHP, MEHHP, MEOHP metabolites can be detected in 98% (65 cases) , 89% (59 cases), 91% (60 cases), 91% (60 cases) of all 66 maternal urine samples, respectively. The median concentrations of test material in case group were 31.20 ng/ml for MBP, 24.61 ng/ml for MEHHP, 11.72 ng/ml for MEOHP and 48.67 ng/ml for SumDEHP which were significantly higher than those of the control group (were 17.32, 12.03, 5.68 and 28.64 ng/ml); 11β-HSD2 activity in case group ((THF+allo-THF)/THE = (0.79 ± 0.09) ng/ml) was significantly lower than that of the control group((THF+allo-THF)/THE = (0.58 ± 0.04) ng/ml); PAEs metabolites MBP (β' = 1.12), MEHHP(β' = 1.14), MEOHP(β' = 1.10), SumDEHP(β' = 1.08) in baby boy mother's urine was reversely correlated to 11β-HSD2 activity.

CONCLUSIONSPAEs could affect fetal development by inhibit 11β-HSD2 activity.

11-beta-Hydroxysteroid Dehydrogenase Type 2 ; Chromatography, Liquid ; Diethylhexyl Phthalate ; analogs & derivatives ; Fetal Development ; Humans ; Infant, Newborn ; Male ; Mass Spectrometry ; Phthalic Acids ; Tetrahydrocortisol ; analogs & derivatives ; Tetrahydrocortisone

OBJECTIVE: To investigate the transcriptome profile of genital tubercles (GTs) in male SD rats and explore the mechanism of hypospadias induced by Di (2-ethylhexyl) phthalate (DEHP). METHODS: Forty time-pregnant SD rats were randomly divided into 4 equal groups, namely GD16 group and GD19 group (in which the male GTs were collected on gestation day[GD]16 and GD19 for RNA-seq, respectively), control group and DEHP exposure group (with administration of oil and 750 mg/kg DEHP by gavage from GD12 to GD19, respectively).In the control and DEHP exposure groups, the GTs were collected from the male fetuses on GD19.5, and scanning electron microscopy and HE staining were used to observe the morphological changes.The differentially expressed genes (DEGs) in the GTs were screened using lllumina HiSeq 2000 followed by GO and KEGG enrichment analyses to characterize the transcriptome profile.Immunofluorescence assay was performed to verify the DEGs (Mafb) identified by RNA-seq results.Immunofluorescence assay and Western blotting were used to examine the expression levels of Mafb in the penile tissue. RESULTS: A total of 1360 DEGs were detected in the GTs between GD16 group and GD19 group by RNA-seq.Among these genes, 797 were up-regulated and 563 were down-regulated.These DEGs were mainly enriched in the cell adhesion plaque signaling pathway, axon guidance signaling pathway, and extracellular matrix receptor signaling pathway.Compared with that in GD16 group, Mafb was significantly up-regulated in GD19 group, which was consistent with the sequencing results.Mafb and β-catenin were significantly down-regulated in DEHP-exposed group compared with the control group ( < 0.01). CONCLUSIONS Mafb expression increases progressively with the development of GTs in male SD rats.DEHP exposure causes significant down-regulation of Mafb and β-catenin, suggesting that β-catenin signaling pathway that affects Mafb is related to DEHP-induced hypospadias in SD rats.
Animals ; Diethylhexyl Phthalate ; Female ; Gene Expression Profiling ; Humans ; Hypospadias ; MafB Transcription Factor ; Male ; Oncogene Proteins ; Phthalic Acids ; Pregnancy ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: Prenatal phthalate exposure has been associated with placental inflammatory factors and infant allergic rhinitis (AR). However, the results are inconclusive. We designed a population-based cohort study to examine the effects of placental inflammatory biomarkers on the sex-dependent associations between maternal phthalate exposure and infant AR. METHODS: A total of 2,348 pregnant women from Ma'anshan, Anhui Province, China, who were screened before antenatal visits and met the inclusion criteria, were included in the present study. We assessed AR in their offspring aged 36 months with a questionnaire. Quantitative PCR was performed to measure placental inflammatory factor mRNAs. The independent samples t-test and multivariable logistic regression were used to determine the associations between infant AR and maternal phthalates. RESULTS: Childhood AR may be related to education and family monthly income ( P = 0.01). The phthalate metabolites, mono (2-ethylhexyl) phthalate (MEHP), mono (2-ethyl-5-hydroxyl) phthalate (MEHHP), in pregnant women were associated with a significantly increased risk for infant AR in males [ P < 0.05; odds ratio ( OR): 1.285; 95% confidence interval ( CI): 1.037-1.591, and OR: 1.232, 95% CI: 1.008-1.507, respectively], but not females. Additionally, irritably-increased expression levels of HO-1 and IL-4 were associated with AR in male infants ( OR: 1.175; 95% CI: 1.038-1.329 and OR: 1.181; 95% CI: 1.056-1.322, respectively). The association between maternal urinary MEHHP and placental HO-1 was marginally significant according to mediation analysis. CONCLUSION The associations of maternal MEHHP and MEOHP levels with fetal AR in males were significant. Placental HO-1 was a fractional mediator in the associations between MEHHP and AR. Thus, the placenta should be further investigated as a potential mediator of maternal exposure-induced disease risk in children.
Biomarkers ; Child, Preschool ; Cohort Studies ; Diethylhexyl Phthalate/analogs & derivatives* ; Female ; Humans ; Interleukin-4/pharmacology* ; Male ; Maternal Exposure/adverse effects* ; Phthalic Acids/adverse effects* ; Placenta ; Pregnancy ; Rhinitis, Allergic/epidemiology*