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OBJECTIVE@#To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.@*METHODS@#Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.@*RESULTS@#Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).@*CONCLUSION@#Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.
Subject(s)
Rats , Male , Animals , Testis , Quercetin/pharmacology , Rats, Sprague-Dawley , NF-E2-Related Factor 2/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Oxidative Stress , Testosterone/pharmacology , Superoxide Dismutase/metabolism , Follicle Stimulating Hormone , Luteinizing HormoneABSTRACT
Resumen Se denominan disruptores endocrinos (DEs) a aquellas sustancias químicas capaces de interferir con la homeostasis hormonal, alterando la síntesis, función, almacenamiento y/o metabolismo de las hormonas. Estas sustancias se encuentran en el ambiente y en una amplia variedad de productos de uso diario, por lo que la exposición humana es permanente. Experimentos con animales han confirmado la capacidad de los DEs para inducir desórdenes reproductivos, por lo que se ha sugerido que podrían ser un factor importante como causa de subfertilidad humana. El bisfenol A, los ftalatos y los compuestos orgánicos persistentes son tres tipos de DEs presentes en el medio ambiente y asociados con alteraciones reproductivas. Consultando las bases de datos MEDLINE y PubMed, en la presente revisión, se reúne bibliografía de los últimos 20 años donde se evalúan los efectos provocados por la exposición a los DEs mencionados en mujeres durante la vida adulta. Se resumen los efectos sobre marcadores de reserva ovárica y los resultados de tratamientos de fertilización in vitro. Por otro lado, se evalúa la evidencia a nivel molecular de los efectos provocados por los DEs sobre la fisiología reproductiva en estudios in vitro e in vivo.
Abstract Endocrine disruptors (EDs) are those chemical substances capable of interfering with hormonal homeostasis, altering the synthesis, function, storage and / or metabolism of hormones. These substances are found in the environment and in a wide variety of products for daily use, so human exposure is permanent. Animal experiments have confirmed the capacity of EDs to induce reproductive disorders, which is why it has been suggested that they could be an important factor in causing human subfertility. Bisphenol A, phthalates and persistent organic compounds are three types of EDs present in the environment and associated with reproductive disorders. Consulting the MEDLINE and PubMed databases, in this review, a bibliography of the last 20 years is gathered where the effects caused by exposure to the mentioned EDs in women during adult life are evaluated. The effects on ovarian reserve markers and the results of in vitro fertilization treatments are summarized. On the other hand, the evidence at the molecular level of the effects caused by EDs on reproductive physiology is evaluated in in vitro and in vivo studies.
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SUMMARY: Di-(2-ethylhexyl) phthalate (DEHP) is among the most common plasticizer additives that humans are in contact with daily. DEHP can be released from plastic and enter the human body, whereby it is metabolized and transformed into oxidative hydrophilic molecules. Clinical follow-ups in patients exposed to this phthalate and investigations in cultures of several cell types have provided information on its effects. For example, it is associated with inhibition of diploid human cell development and morphological changes in cultured germ cells. Although skeletal muscle represents around 50 % of the human body mass, knowledge about the effects of DEHP on this tissue is poor. Cultured skeletal muscle cells were exposed to DEHP (1 mM) for 13 days with the aim of exploring and evaluating some of the potential morphological effects. Three culture development parameters and nine cell characteristics were monitored during the bioassay. At 13 days, growth area, cell viability, and concentration of total proteins were lower in DEHP exposed than in control cells. Cell width and area, as well as the diameter of the nucleus and nucleolus, were greater in exposed cells than in control cells. These are interpreted as signs of cytotoxicity and suggest potential adverse effects on the development of skeletal muscle cells from DEHP exposure, as reported for other cell types.
RESUMEN: Diariamente los seres humanos tenemos contacto con aditivos plastificantes, el di-(2-etilhexil) ftalato (DEHP) se encuentra entre los más comunes. El DEHP puede liberarse del plástico e ingresar al cuerpo humano, donde es metabolizado y transformando en moléculas hidrofílicas oxidativas. Seguimientos en pacientes expuestos a este ftalato e investigaciones en cultivos de varios tipos celulares han aportado información sobre sus efectos. El DEHP es asociado con la inhibición del desarrollo de células humanas diploides y cambios morfológicos en células germinales en cultivo. Sin embargo, aún es poco lo que se sabe sobre los efectos en el músculo esquelético, a pesar de que este tejido representa alrededor del 50 % de la masa corporal del humano. Para explorar y evaluar algunos efectos morfológicos en células de músculo esquelético, cultivos primarios fueron expuestos a DEHP (1 mM) durante 13 días. Se dio seguimiento a tres parámetros de desarrollo del cultivo y nueve características celulares. Al término de 13 días de exposición, los valores del área de crecimiento, viabilidad celular y concentración de proteínas totales fueron inferiores con respecto a los cultivos control. Se observaron cambios morfométricos en las células expuestas. Particularmente, el ancho y área celular, así como los diámetros del núcleo y nucleolos, fueron mayores a los registros en las células control. Estos resultados se interpretan como signos de citotoxicidad y sugieren efectos potencialmente adversos en el desarrollo de las células del músculo esquelético ante una exposición al DEHP, como se ha registrado para otros tipos celulares.
Subject(s)
Humans , Plasticizers/toxicity , Muscle, Skeletal/drug effects , Diethylhexyl Phthalate/toxicity , Biological Assay , Muscle, Skeletal/cytology , Environmental Pollutants , Primary Cell CultureABSTRACT
This paper describes the electrodeposition of polyphosphate-doped polypyrrole/nanosilica nano-composite coating on steel wire for direct solid-phase microextraction of bisphenol A and five phthalates. We optimized influencing parameters on the extraction efficiency and morphology of the nanocomposite such as deposition potential, concentration of pyrrole and polyphosphate, deposition time and the nanosilica amount. Under the optimized conditions, characterization of the nanocomposite was inves-tigated by scanning electron microscopy and Fourier transform infra-red spectroscopy. Also, the factors related to the solid-phase microextraction method including desorption temperature and time, extrac-tion temperature and time, ionic strength and pH were studied in detail. Subsequently, the proposed method was validated by gas chromatography-mass spectrometry by thermal desorption and acceptable figures of merit were obtained. The linearity of the calibration curves was between 0.01 and 50 ng/mL with acceptable correlation coefficients (0.9956-0.9987) and limits of detection were in the range 0.002-0.01 ng/mL. Relative standard deviations in terms of intra-day and inter-day by five replicate analyses from aqueous solutions containing 0.1 ng/mL of target analytes were in the range 3.3％-5.4％ and 5％-7.1％, respectively. Fiber-to-fiber reproducibilities were measured for three different fibers prepared in the same conditions and the results were between 7.3％ and 9.8％. Also, extraction recoveries at two different concentrations were ≥96％. Finally, the suitability of the proposed method was demonstrated through its application to the analysis of some eye drops and injection solutions.
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BACKGROUND@#Studies reported adverse behavioral development including internalizing and externalizing problems in association with prenatal exposure to bisphenol A (BPA) and phthalates; however, findings were not sufficient due to using different assessment tools and child ages among studies. This study aimed to examine associations between maternal serum levels of BPA and phthalate metabolites and behavioral problems at preschool age.@*METHODS@#The Strengths and Difficulties Questionnaire (SDQ) was used to assess behavioral problems at 5 years of age. BPA and phthalate metabolite levels in the first trimester maternal serum was determined by LC-MS/MS for 458 children. Variables used for adjustment were parental ages, maternal cotinine levels, family income during pregnancy, child sex, birth order, and age at SDQ completed.@*RESULTS@#The median concentrations of BPA, MnBP, MiBP, MEHP, and MECPP, primary and secondary metabolites of phthalates, were 0.062, 26.0, 7.0, 1.40, and 0.20 ng/ml, respectively. MECPP level was associated with increase conduct problem risk (OR = 2.78, 95% CI 1.36-5.68) overall and the association remained after child sex stratification, and odds ratios were increased with wider confidence interval (OR = 2.85, 95% CI 1.07-7.57 for boys, OR = 4.04, 95% CI 1.31-12.5 for girls, respectively). BPA, ∑DBP (MnBP + MiBP), and ∑DEHP (MEHP+MECPP) levels were not associated with any of the child behavioral problems.@*CONCLUSIONS@#Our analyses found no significant association between BPA or summation of phthalate metabolite levels and any of the behavioral problems at 5 years of age but suggested possible association between MECPP levels and increased risk of conduct problems.
Subject(s)
Adult , Child, Preschool , Female , Humans , Male , Pregnancy , Age Factors , Benzhydryl Compounds , Blood , Environmental Exposure , Phenols , Blood , Phthalic Acids , Blood , Prenatal Exposure Delayed Effects , Epidemiology , Problem Behavior , Smoking , Epidemiology , Socioeconomic FactorsABSTRACT
A new method for the rapid determination of total phthalates (PAEs) in edible oils was developed. The PAEs in edible oils all were hydrolyzed to phthalic acid with tetrabutylammonium chloride (TBAC) as catalyst. Then phthalic acid was extracted by the supramolecular solvent ( SUPRAS) made up of octanol, tetrahydrofuran and aqueous solution, and detected by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS / MS). As a result, hydrolysis time was 10 min. The linear range of phthalic acid was 0. 05- 2. 0 mg / L with a good correlation coefficients ( r > 0. 999). The limits of detection ( LOD) and quantification (LOQ) were 5. 41 and 18. 05 μg / kg, respectively. The recoveries of target analyte at three spiked levels were in the range of 84. 6% - 104. 5% . The repeatability, expressed as relative standard deviation (RSD), was 2. 6% for intra-day and 3. 7% for inter-day. The total PAEs content of 12 edible oils was found in the range of 0. 30-1. 09 mg / kg.
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Hexafluoroisopropanol (HFIP)-induced sodium dodecyl sulfate/dodecyltrimethylammonium bromide (SDS/DTAB) catanionic surfactant coacervate extraction method coupled with high performance liquid chromatography (HPLC) was used to detect the migration of phthalates from disposable tablewares to drinking water. The concentration factors are larger than 82 and extraction recoveries over 53%for water samples spiked with 100 or 200 ng/mL phthalates. Limit of detection is in the range of 1.0–2.6 ng/mL. Good linearity with correlation coefficients larger than 0.9985 is obtained in the concentration of 20–1500 or 40–3000 ng/mL. Relative recoveries are from 82.4%to 123.6%for water samples spiked with 30/60, 250/500, and 1500/3000 ng/mL phthalates, respectively. Relative standard deviations (RSDs) are 0.4%–7.4% for intraday precision (n ? 5) and 0.6%–7.8% for interday precision (n ? 3). Four of studied phthalates are found in the drinking water samples prepared from four kinds of tablewares.
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Objective:To establish a GC-MS method for the simultaneous determination of 16 phthalate ester plasticizers in oral liquid preparations, compare the purification effect of liquid preparations by liquid-liquid extraction and solid phase extraction and opti-mize the operating parameters to determine the optimal experimental conditions. Methods:The samples were operated by liquid-liquid extraction and solid phase extraction, respectively. Selective ion monitor ( SIM) was adopt, phthalate esters were identified by the rela-tive abundance of major characteristic ions and the content was determined by an external standard method. Results:When the samples were operated by liquid-liquid extraction, the interference was strong with many impurity peaks. Therefore, the solid phase extraction was adopted for the sample pretreatment. GC-MS was used to detect the residues of 16 phthalate ester plasticizers in oral liquid prepara-tions. The detection limit was 0. 02μg·g-1 ,while the calibration curve showed good linearity within the range of 0. 25-8. 0μg·ml-1 with the correlation coefficient between 0. 990 7 and 0. 999 8. The average recoveries were 76. 0%-95. 4%. The relative standard devi-ations were between 2. 3% and 9. 6%(n=6). Conclusion: Pretreated by solid phase extraction, the residues of 16 phthalate ester plasticizers in oral liquid preparations can be detected by GC-MS with the properties of simple, fast, precise and sensitive, and it is suitable for the determination of phthalate esters in oral liquid preparations.
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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.
Subject(s)
Humans , Biomarkers , Chromatography, Liquid , Dibutyl Phthalate , Diethylhexyl Phthalate , Limit of Detection , Occupational Exposure , Phthalic Acids , Plasticizers , Plastics , Tandem Mass SpectrometryABSTRACT
Objective To establish a method for the determination of phthalates in water by solid phase extraction-gas chromatography-mass spectrometry(SPE-GC-MS).Methods The water samples were extracted and enriched by solid phasse extraction,using 10%methanol-methyl tert-butyl ether as eluant,dimethylphthalate(DMP),diethylphthalate(DEP),dibutylphthalate (DBP)and diethylhexylphthalate(DEHP)were determined by gas chromatography-mass spectrometry with selected ion monitoring mode(SIM).Results The concentration had a good linear range in the range of 0.00~10.00?g/ml,the correlation coefficient was above 0.998.The detection limit of DMP,DEP,DBP and DEHP were 2.7,2.1,1.6 and 2.5 ng/L respectively,the average recovery rate and the RSD of the method were 78.0%～102.5%and 3.3%～7.8%respectively.Conclusion This method,with small amount of solvent,is simple,fast,accurate and is applicable to the determination of phthalates in water.
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Objective To know the pollution level of phthalates in Jiulong River source water and the purification efficiency by conventional water treatment processes. Methods The samples of Jiulong River source water and treated water from two waterworks were collected and analyzed with GC-MS during Aug.-Sep.2006. Results Jiulong River had been polluted by phthalates. The prominent phthalates pollutants were dibutyl phthalate (DBP) and diethyl phthalate(DEP). The maximum concentrations reached 17.238 ?g/L and 11.701 ?g/L, respectively. PAEs content in tap-water was lower than the standard limits. Conclusion The conventional water treatment processes, preoxidation, coagulation, sedimentation, filtration and disinfection, could remove phthalates from the drinking water to a certain degree, but the risk of phthalates pollution in drinking water still exists.
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Objective To explore the kinds and levels of phthalates leaching from disposable plastic products. Methods Samples of peritoneal dialysis solution, blood preservative solution, infusion instruments, preservative film, disposable plastic bags and water in plastic bottles were analyzed for phthalates by RP-HPLC after liquid-liquid extraction and/ or solid phase extraction. Results Di(2-ethylhexyl) phthalate (DEHP) was leached from all medical instruments, the maximum level of which reached 77.51?g/ L. Di-n-butyl phthalate was leached from disposable plastic bags, the level of which reached 91.45?g/ kg. Phthalates were not found in samples of preservative film and water in plastic bottles. Conclusion As DEHP leaching from the medical instruments might directly enter the human body, attention should be paid to its health hazards.
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Objective To establish a high performance liquid chromatography method for simultaneous determination of 10 kinds of phthalates in cosmetics. Methods 10 kinds of phthalates were separated on a C18 column using methanol-water as mobile phase at a flow rate of 1.0 ml/min, 25℃ column temperature and 280 nm detection wave. Results The detection limit of 10 kinds of phthalates were 0.1-7 mg/L. The precision was less than 3.95% and recovery rates varied from 98.59% to 108.07%. Conclusion The experimental results show that the method is simple, precise and accurate and suitable to simultaneous determination of 10 kinds of phthalates in cosmetics.
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Objective To study the toxicokinetics of phthalates in male rabbits. Methods Concentrations of DEHP or DBP in plasma of 6 healthy male rabbits were determined by RP-HPLC after constant rate infusion of 0.5 g/kg DEHP or DBP(IV). The toxicokinetic parameters were computed by 3P87 program. Results The toxicokinetic model of DEHP and DBP were both first-order elimination and two-compartment model with constant rate infusion. The main toxicokinetic parameters of DEHP were as follows: distribution phose t1/2(?)=0.101 h; elimination phase t1/2(?)=12.701 h; CLs=0.013 g?kg-1?h-1. The main toxicokinetic parameters of DBP were as follows: t1/2(?)=0.441 h; t1/2(?)=31.311 h; CLs=0.021 g?kg-1?h-1. Conclusion DEHP and DBP were both first order elmination and two-compartment medol with constand rate intusion(IV). DEHP and DBP could be rapidly eliminated in male rabbits.
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Objective To know phthalates(PAEs) pollution in drinking water of Nantong City. Methods With solid phase extraction and gas chromatography-mass spectroscope(GC-MS),main phthalates in drinking water were determined. Results Phthalates could be detected in all the source water, product water and tap water samples, mainly were di-n-butyl phthalate(DBP) and di(2-ethylhexyl) phthalate(DEHP),ranged from 1.25 to 4.59 ?g/L and from 0.97 to 3.57 ?g/L respectively. PAEs levels in product water were less than those in source water. The highest removal rate of DBP was 50%. PAEs levels in tap water were higher than those in product water,sometimes even higher than those in source water. Conclusion PAEs can not be effectively removed from source water after general water treatment process.