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Carolina Aristizabal-Ciro, Ana María Botero-Coy, Francisco J López, Gustavo A Peñuela
In this work, the presence of selected emerging contaminants has been investigated in two reservoirs, La Fe (LF) and Rio Grande (RG), which supply water to two drinking water treatment plants (DWTPs) of Medellin, one of the most populated cities of Colombia. An analytical method based on solid-phase extraction (SPE) of the sample followed by measurement by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed and validated for this purpose. Five monitoring campaigns were performed in each reservoir, collecting samples from 7 sites (LF) and 10 sites (RG) at 3 different depths of the water column...
January 20, 2017: Environmental Science and Pollution Research International
Kevin M Beene, Andrew Scheman, Dave Severson, Margo J Reeder
BACKGROUND: Preservatives are known causes of allergic contact dermatitis. OBJECTIVE: The aim of this study was to determine the prevalence of preservatives in each product category in the Contact Allergen Management Program and compare prevalence with reported rates of allergic contact dermatitis. METHODS: Contact Allergen Management Program product information was queried based on the 53 approved preservatives for cosmetic products by the European Union and Association of Southeast Asian Nations plus 5 additional preservatives used in US products...
January 2017: Dermatitis
Michael B Hicks, Leah Salituro, Ian Mangion, Wes Schafer, Rong Xiang, Xiaoyi Gong, Christopher J Welch
The use of a coulometric array detector in tandem with HPLC-UV was evaluated for the absolute quantitation of pharmaceutical compounds without standards, an important capability gap in contemporary pharmaceutical research and development. The high-efficiency LC flow-through electrochemical detector system allows for the rapid evaluation of up to 16 different potentials, aiding in the identification and quantitation of electrochemically reactive species. By quantifying the number of electrons added or removed from an analyte during its passage through the detector, the number of moles of the analyte can be established...
January 18, 2017: Analyst
Chuansha Wu, Wenqian Huo, Yuanyuan Li, Bin Zhang, Yanjian Wan, Tongzhang Zheng, Aifen Zhou, Zhong Chen, Minzheng Qian, Yingshuang Zhu, Yangqian Jiang, Hongxiu Liu, Jie Hu, Xi Chen, Bing Xu, Wei Xia, Shunqing Xu
BACKGROUND: Parabens are suspected to impair fetal growth because of their endocrine disrupting effects. Epidemiological studies regarding the effects of prenatal exposure to parabens on birth outcomes are limited. OBJECTIVES: Our aim was to evaluate the association between prenatal paraben exposure and size of infants at birth. METHODS: Within the longitudinal Healthy Baby Cohort (HBC) in Hubei Province, China, we randomly selected 1006 mother-infant pairs recruited in Wuhan City in 2014...
December 27, 2016: Chemosphere
Jianqiu Guo, Chunhua Wu, Dasheng Lu, Shuai Jiang, Weijiu Liang, Xiuli Chang, Hao Xu, Guoquan Wang, Zhijun Zhou
Parabens, known as ubiquitous preservatives, have been linked to adverse health outcomes in humans. This study aimed to examine urinary paraben concentrations of children at 3 years of age and evaluate their associations with anthropometric parameters. Urinary parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), butylparaben (BuP) and benzylparaben (BeP) were measured among 436 children in a birth cohort using gas chromatography with tandem mass spectrometry. Generalized linear models were performed to evaluate associations of paraben exposures with age- and sex-specific z scores, including weight, height, weight for height and body mass index...
December 26, 2016: Environmental Pollution
Chaofeng Song, Hongjuan Hu, Hongyi Ao, Yonghong Wu, Chenxi Wu
The extensive use of parabens as preservatives in food and pharmaceuticals and personal care products results in frequent detection of their residuals in aquatic environment. In this work, the adsorption and removal of four parabens (methyl-, ethyl-, propyl-, and butyl-paraben) and two chlorinated methyl-parabens (CMPs) by periphyton were studied. Characteristics of the periphyton were identified to explore the possible relationship between paraben removal and periphyton properties. Results showed that linear adsorption coefficients (K d) vary from 554...
December 29, 2016: Environmental Science and Pollution Research International
Aysegul Kutluay Baytak, Tugce Teker, Sehriban Duzmen, Mehmet Aslanoglu
A composite of carbon nanofibers (CNFs) and tri-metallic nanoparticles of gold, cobalt and nickel were used for the preparation of a novel voltammetric platform. The proposed voltammetric platform was utilized for quantifying ethyl paraben (EPB) in pharmaceutical and cosmetic products. The electrode layers were characterized by utilizing X-ray diffraction method (XRD) and Fourier transform infrared spectroscopy (FTIR). The electrode system, (Au-Ni-Co)NPs-CNFs/GCE, exhibited high catalytic activity and enhanced the electrochemical behaviour of EPB compared with several other electrodes...
March 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Neda Feizi, Yadollah Yamini, Morteza Moradi, Meghdad Karimi, Qamar Salamat, Hatam Amanzadeh
A new supramolecular solvent (SUPRAS) made up of aggregates of gemini surfactant was introduced. A microextraction method, based on the SUPRAS followed with high performance liquid chromatography-ultraviolet detection, was applied for the determination of parabens in cosmetics, beverages and water samples. A SUPRAS is a nano-structured liquid made up of surfactant aggregates synthesized through a self-assembly process. In the present work, a new gemini-based SUPRAS was introduced. Methyl paraben (MP), ethyl paraben (EP), and propyl paraben (PP) were extracted on the basis of π-cation and Van der Waals interactions into the SUPRAS...
February 8, 2017: Analytica Chimica Acta
Shizong Wang, Jianlong Wang, Yuliang Sun
Chlorinated paraben, namely, methyl 3, 5-dichloro-4-hydroxybenzoate (MDHB) is the by-product of chlorination disinfection of paraben and frequently detected in the aquatic environments, which exhibited higher persistence and toxicity than paraben itself. In this paper, the combined irradiation and biological treatment process was employed to investigate the removal of MDHB from aqueous solution. The results showed that the removal efficiency of MDHB and total organic carbon (TOC) by irradiation process increased with radiation dose no matter what the initial concentration of MDHB was...
December 18, 2016: Journal of Environmental Management
F Finot, A Kaddour, L Morat, I Mouche, N Zaguia, C Cuceu, D Souverville, S Négrault, O Cariou, A Essahli, N Prigent, J Saul, F Paillard, L Heidingsfelder, P Lafouge, M Al Jawhari, W M Hempel, M El May, B Colicchio, A Dieterlen, E Jeandidier, L Sabatier, J Clements, R M'Kacher
The ability of parabens to promote the appearance of multiple cancer hallmarks in breast epithelium cells provides grounds for regulatory review of the implication of the presence of parabens in human breast tissue. It is well documented that telomere dysfunction plays a significant role in the initiation of genomic instability during carcinogenesis in human breast cancer. In the present study, we evaluated the genotoxic effect of ethyl 4-hydroxybenzoate (ethyl-paraben), with and without metabolic activation (S9), in studies following OECD guidelines...
December 20, 2016: Journal of Applied Toxicology: JAT
Alexandros G Asimakopoulos, Madhavan Elangovan, Kurunthachalam Kannan
Parabens (p-hydroxybenzoic acid esters), bisphenols, benzophenone-type UV filters, triclosan, and triclocarban are used in a variety of consumer products, including baby teethers. Nevertheless, the exposure of infants to these chemicals through the use of teethers is still unknown. In this study, 59 teethers, encompassing three types, namely solid plastic, gel-filled, and water-filled (most labeled "bisphenol A-free"), were collected from the U.S. market and analyzed for 26 potential endocrine-disrupting chemicals (EDCs) from intact surfaces through migration/leaching tests performed with Milli-Q water and methanol...
December 20, 2016: Environmental Science & Technology
Yang Wu, Qian Sun, Yu-Wen Wang, Cheng-Xun Deng, Chang-Ping Yu
The biodegradability of two typical parabens (methylparaben and propylparaben) in activated sludge, at initial concentrations of 1mgL(-1) or 10mgL(-1), was investigated under aerobic and anaerobic conditions. The results showed that microorganisms played a key role in degradation of parabens in WWTPs, especially in aerobic systems. The half-lives of methylparaben and propylparaben under aerobic conditions have been estimated to range between 15.8 and 19.8min, and benzoic acid was found to be one of the major biodegradation products...
December 16, 2016: Ecotoxicology and Environmental Safety
M E Watkins, S Wring, R Randolph, S Park, K Powell, M Lutz, M Nowakowski, R Ramabhadran, P L Domanico
Tenofovir disoproxil fumarate (TDF), the bisphosphonate ester prodrug of tenofovir (TFV), has poor bioavailability due to intestinal degradation and efflux transport. Reformulation using FDA-approved esterase and efflux inhibitors to increase oral bioavailability could provide lower dose alternatives and reduce costs for patients with HIV in resource-limited settings (RLS). Inhibition of mucosal and intracellular esterases was studied in human and rat intestinal extracts (S9), where TDF was protected by the carboxylesterase (CE) inhibitor bis-para-nitrophenylphosphate (BNPP), the ester mix EM1, and the generally-recognized-as-safe (GRAS) excipient propylparaben (PP)...
December 13, 2016: Journal of Pharmaceutical Sciences
Julia Martín, Juan Luis Santos, Irene Aparicio, Esteban Alonso
In this paper, a method for the determination of four groups of endocrine-disrupting compounds in human hair is proposed. Target compounds were a plastic monomer (bisphenol A), three parabens commonly used as preservatives (methylparaben, ethylparaben and propylparaben), six perfluoroalkyl compounds commonly used as water, oil and dirt repellents (perfluorooctane sulfonic acid and five perfluoroalkyl carboxylic acids, with alkyl chains from four to eight carbon atoms) and a brominated flame retardant (hexabromocyclododecane)...
November 16, 2016: Analytica Chimica Acta
Shiqin Yu, Manuel R Plan, Gal Winter, Jens O Krömer
para-Hydroxy benzoic acid (PHBA) is the key component for preparing parabens, a common preservatives in food, drugs, and personal care products, as well as high-performance bioplastics such as liquid crystal polymers. Pseudomonas putida KT2440 was engineered to produce PHBA from glucose via the shikimate pathway intermediate chorismate. To obtain the PHBA production strain, chorismate lyase UbiC from Escherichia coli and a feedback resistant 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase encoded by gene aroG(D146N) were overexpressed individually and simultaneously...
2016: Frontiers in Bioengineering and Biotechnology
Xiaohong Xue, Jingchuan Xue, Wenbin Liu, Douglas H Adams, Kurunthachalam Kannan
Despite the widespread use of parabens in a range of consumer products, little is known about bioaccumulation of these chemicals in aquatic environments. In this study, six parabens and four of their common metabolites were measured in abiotic (water, sediment) and biotic (fish including sharks, invertebrates, plants) samples collected from a subtropical marine food web in coastal Florida. Methyl paraben (MeP) was found in all abiotic (100%) and a majority of biotic (87%) samples. 4-Hydroxy benzoic acid (4-HB) was the most abundant metabolite, found in 97% of biotic and all abiotic samples analyzed...
January 5, 2017: Environmental Science & Technology
Aleksandra Chmielewska, Lucyna Konieczna, Tomasz Bączek
The research into the separation of drug enantiomers is closely related to the safety and efficiency of the drugs. The aim of this study was to develop a simple and validated HPLC method to analyze cetirizine enantiomers. In the case of liquid dosage forms, besides the active substance in large amounts there are usually also inactive ingredients such as methyl- and propylparaben. Unfortunately, these compounds can interfere with the analyte, inter alia during chiral separation of the analyte enantiomers. The proposed innovative two-step liquid-liquid extraction procedure allowed for the determination of cetirizine enantiomers (along with M and P parabens) also in liquid dosage forms...
December 7, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Yiqun Chen, Pinya Deng, Pengchao Xie, Ran Shang, Zongping Wang, Songlin Wang
We evaluated the degradation of methylparaben (MeP) and ethylparaben (EtP), two representative parabens, using the heat-activated persulfate system in a laboratory. Both sulfate and hydroxyl radicals contributed to the removal of the two parabens. The degradations of both MeP and EtP were improved by increasing the heating temperature or persulfate dose in accordance with a pseudo-first-order reaction model. The oxidation efficiency of parabens was found to be pH-dependent; decreasing in the order pH 5.0 > 7...
February 2017: Chemosphere
Kotryna Linauskienė, Laura Malinauskienė, Audra Blažienė
BACKGROUND: Monitoring trends of positive patch test reactions is useful for epidemiological surveillance and contact allergy prevention, and has not previously been reported in Lithuania. OBJECTIVES: To examine and compare changes in the prevalence of contact allergy to European baseline series allergens in adults with suspected contact dermatitis during a 9-year period. METHODS: In this retrospective study, patch test results of 297 consecutive patients, tested with the European baseline series in 2014-2015, were analysed and compared with the data published earlier in Lithuania...
December 4, 2016: Contact Dermatitis
Petra Apel, Jürgen Angerer, Michael Wilhelm, Marike Kolossa-Gehring
The German Human Biomonitoring Commission (HBM Commission) derives health-related guidance values (Human Biomonitoring assessment values, HBM values) according to the procedures described in the HBM Commission's position papers. Since the last adaption of the methodology in 2014, the HBM Commission has established a series of new HBM values, mainly on the basis of internationally agreed TDI/RfD values, or of toxicologically well- founded points of departure observed in animal studies. The derivation of these new HBM values for HBCDD, triclosan, 2-MBT, PFOA and PFOS as well as for the metabolites of glycol ethers, of Hexamoll(®) DINCH(®), DPHP, DEHTP, NMP, NEP, and 4-MBC is specified, and the HBM values are presented together with already established HBM values for other substances...
September 17, 2016: International Journal of Hygiene and Environmental Health
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