Phthalate esters are used widely as plasticizers for polyvinylchloride (PVC) formulations in several applications, including medical devices, toys, food wraps, and building products, to impart flexibility to an otherwise rigid PVC. Di-(2-ethylhexyl)phthalate (DEHP) is the most commonly used plasticizer. Because DEHP does not bind with the plastic, it leaches with time and use from vinyl products, thus becoming a ubiquitous environmental contaminant (Bauer and Herrmann 1997;Bradbury 1996;Giam et al. 1978;Griffiths et al. 1985;Mayer et al. 1972;Mes et al. 1974;Øie et al. 1997;Sharman et al. 1994). In particular, leaching of DEHP from PVC medical devices and deposits in tissue have been well documented (Latini 2000;Tickner et al. 2001). Because the DEHP action depends on dose, time, and age (Latini 2000) and because DEHP effects are influenced by the stage of development at exposure among animals (Akingbemi et al. 2001), the DEHP-related exposure risk is potentially higher for the developing fetus and newborn, particularly preterm. Recently, our preliminary findings indicated that the exposure to these environmental contaminants begins during intrauterine life, that these chemicals are able to cross the placental barrier, and that fetal exposure is closely related to maternal exposure (Latini et al. 2003). The aim of this study was to measure concentrations of DEHP and/or its main metabolite, mono-(2-ethylhexyl)phthalate (MEHP), in a larger population of human neonates and to evaluate possible biologic effects from prenatal exposure to DEHP and/or MEHP. Patients and MethodsSubjects. Cord blood samples were collected from 84 consecutive newborns (82 singletons, two twins), born at the general-practice Brindisi Hospital, with the following characteristics: 39 male, 45 female; maternal age at delivery, 29.5 ± 5.1 years (range = 18-42); vaginal delivery, n = 65 (77.4%); gestational age, 38.4 ± 2.2 weeks (range = 27-42); birth weight, 3,220 ± 680 g, (range = 1,150-4,350); 1-min Apgar score, 7.9 ± 0.9; 5-min Apgar score, 8.8 ± 0.5. Eleven of 84 infants were preterm; only three had very low birth weight. Moreover, four infants who were small for gestational age (SGA) were present in our population. None of the examined infants was born after in vitro fertilization pregnancy. The study was approved by the ethics committee of the Brindisi Hospital (Brindisi, Italy), and written informed consent from the parents was obtained. Blood specimens were immediately centrifuged (3,500 × g, 7 min), and serum was stored at -20°C until assay. To avoid any contamination from plasticizers in lab equipment, the serum sample collection, preservation, and treatment were performed only with glass devices. The concentrations of DEHP and MEHP were determined by highperformance liquid chromatography, at the Department of Chemistry of the University of L'Aquila, an institution certified in agreement with the International Organization for Standardization 9001 quality system, as described previously .Data analysis. Data are expressed as mean ± SD...
Background: Di(2-ethylhexyl)phthalate (DEHP), the most commonly used plasticizer, is a widespread ubiquitous environmental contaminant. The potential health hazards from exposure to DEHP and its main metabolite, mono(2-ethylhexyl)phthalate (MEHP), have been well documented. Exposure to DEHP and MEHP in humans at risk, such as pregnant women and human fetuses, has not been tested. Methods: Plasma DEHP and MEHP concentrations were measured in a total of 24 consecutive mother-infant pairs by high performance liquid chromatography. Associations between DEHP/MEHP and infant characteristics were tested using Fisher’s exact test, unpaired t tests and univariate linear regression analysis. Results: Measurable DEHP and MEHP concentrations were found in 17/24 (70.8%) and 18/24 (75%) maternal plasmas, respectively, and in 11/25 (44%) and 18/25 (72.0%) cord samples, respectively. Either DEHP or MEHP were detectable in 21/24 (87.5%) maternal plasmas and 19/25 (76%) cord samples. The mean DEHP concentrations in maternal and cord plasmas were 1.15 ± 0.81 and 2.05 ± 1.47 µg/ml, respectively. The mean MEHP concentrations were 0.68 ± 0.85 and 0.68 ± 1.03 µg/ml, respectively. No significant correlations were found between maternal and cord blood DEHP, maternal and cord blood MEHP, maternal DEHP and cord blood MEHP, or maternal MEHP and cord blood DEHP plasma concentrations. Conclusion: Although the effects of perinatal exposure to phthalates need further research, our findings: (i) confirm the high frequency of DEHP and/or MEHP exposure in human pregnancies; (ii) indicate that the exposure to these environmental contaminants begins during intrauterine life, and (iii) suggest that fetal exposure is closely related to the maternal exposure.
We designed, fabricated, and characterized four arrays of horn-coupled, lumped element kinetic inductance detectors (LEKIDs), optimized to work in the spectral bands of the balloon-borne OLIMPO experiment. OLIMPO is a 2.6 m aperture telescope, aimed at spectroscopic measurements of the Sunyaev-Zel'dovich (SZ) effect. OLIMPO will also validate the LEKID technology in a representative space environment. The corrected focal plane is filled with diffraction limited horn-coupled KID arrays, with 19, 37, 23, 41 active pixels respectively at 150, 250, 350, and 460 GHz.Here we report on the full electrical and optical characterization performed on these detector arrays before the flight. In a dark laboratory cryostat, we measured the resonator electrical parameters, such as the quality factors and the electrical responsivities, at a base temperature of 300 mK. The measured average resonator Qs are 1.7 × 10 4 , 7.0 × 10 3 , 1.0 × 10 4 , and 1.0 × 10 4 for the 150, 250, 350, and 460 GHz arrays, respectively. The average electrical phase responsivities on resonance are 1.4 rad/pW, 1.5 rad/pW, 2.1 rad/pW, and 2.1 rad/pW; the electrical noise equivalent powers are 45 aW/ √ Hz, 160 aW/ √ Hz, 80 aW/ √ Hz, and 140 aW/ √ Hz, at 12 Hz. In the OLIMPO cryostat, we measured the optical properties, such as the noise equivalent temperatures (NET) and the spectral responses. The measured NET RJ s are 200 µK √ s, 240 µK √ s, 240 µK √ s, and 340 µK √ s, at 12 Hz; under 78, 88, 92, and 90 mK Rayleigh-Jeans blackbody load changes respectively for the 150, 250, 350, and 460 GHz arrays. The spectral responses were characterized with the OLIMPO differential Fourier transform spectrometer (DFTS) up to THz frequencies, with a resolution of 1.8 GHz.
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