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Phthalates are common in polyvinyl chloride (PVC) plastics and numerous consumer goods in our homes from which they can migrate and adhere to indoor dust particles. It is known that indoor dust exposure contribute to human phthalate intake; however, there is a lack of large studies with a repeated-measure design investigating how phthalate levels in indoor dust may vary over time in people's homes. This study investigated levels of seven phthalates and one alternative plasticiser di-iso-nonyl-cyclohexane-di-carboxylate (DiNCH) in bedroom dust collected prenatally around week 25 during pregnancy and postnatally at six months after birth, from 496 Swedish homes. Prenatal and postnatal phthalate levels were compared using correlation and season-adjusted general linear regression models. Over the nine-month period, levels of six out of seven phthalates were associated as indicated by a positive Pearson correlation (0.18 < r < 0.50, P < .001) and Lin's concordance correlation between matched prenatal and postnatal dust samples. Compared to prenatal levels, the season-adjusted postnatal levels decreased for five phthalates, whilst di-ethyl-hexyl phthalate (DEHP), di-2-propylheptyl phthalate (DPHP) and DiNCH increased. The results suggest that families with higher phthalate levels in bedroom dust during pregnancy are likely to remain among those with higher levels in the infancy period. However, all average phthalate levels changed over this specific nine-month period suggesting that available phthalate sources or their use were altered between the dust collections. Changes in home characteristics, family lifestyle, and phthalate replacement trends may contribute to explain the differences.
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Poluição do Ar em Ambientes Fechados , Ácidos Ftálicos , Poeira , Exposição Ambiental/análise , Feminino , Humanos , Ácidos Ftálicos/análise , GravidezRESUMO
Diisononyl phthalate (DINP) is one of plasticisers most employed in the production of plastic materials and belongs to the most important environmental contaminants. In this work, a consortium of saline soil bacterial (SSB) capable of degrading DINP is presented. The genera of SSB-consortium were Serratia sp., Methylobacillus sp., Achromobacter sp., Pseudomonas sp., Stenotrophomonas sp., Methyloversatilis sp., Delftia sp. and Brevundimonas sp. Response surface methodology (RSM) study was employed to optimise and evaluate the culture conditions to improve the biodegradation of DINP. The optimal conditions were a pH 7.0, 31 °C and an initial DINP concentration of 500 mg L-1, resulting in almost complete biodegradation (99%) in 168 h. DINP degradation followed a first-order kinetic model, and the half-life was 12.76 h. During the biodegradation of DINP, 4-derived compounds were identified: monoisononyl phthalate, methyl nonyl phthalate, iso-nonanol and dimethyl phthalate. The metabolite profiling indicated that DINP was degraded through simultaneous pathways of de-esterification and ß-oxidation. Results suggest that the SSB-consortium could be useful for efficient biodegradation of the DINP-contaminated environments. KEY POINTS: ⢠DINP degradation is mediated by de-esterification and ß-oxidation processes. ⢠Temperature and the concentration of the substrate are key factors for DINP biodegradation ⢠The SSB-consortium has the ability to biodegrade 99% of DINP (500 mg L-1).
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Achromobacter , Dietilexilftalato , Ácidos Ftálicos , Biodegradação Ambiental , SoloRESUMO
Wheat gluten biopolymers generally become excessively rigid when processed without plasticisers, while the use of plasticisers, on the other hand, can deteriorate their mechanical properties. As such, this study investigated the effect of carbon black (CB) as a filler into glycerol-plasticised gluten to prepare gluten/CB biocomposites in order to eliminate the aforementioned drawback. Thus, biocomposites were manufactured using compression moulding followed by the determination of their mechanical, morphological, and chemical properties. The filler content of 4 wt% was found to be optimal for achieving increased tensile strength by 24%, and tensile modulus by 268% along with the toughness retention based on energy at break when compared with those of glycerol-plasticised gluten. When reaching the filler content up to 6 wt%, the tensile properties were found to be worsened, which can be ascribed to excessive agglomeration of carbon black at the high content levels within gluten matrices. Based on infrared spectroscopy, the results demonstrate an increased amount of ß-sheets, suggesting the formation of more aggregated protein networks induced by increasing the filler contents. However, the addition of fillers did not improve fire and water resistance in such bionanocomposites owing to the high blend ratio of plasticiser to gluten.
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Glutens/química , Glicerol/química , Plastificantes/química , Fuligem/química , Triticum/químicaRESUMO
Due to the lack of research on the co-effects of microplastics and trace metals in the environment on nitrogen cycling-related functional microorganisms, the occurrence of microplastics and one of their plasticisers, phthalate esters, as well as trace metals, were determined in soils and river sediments in the Qinghai-Tibet Plateau. Relationship between microplastics and phthalate esters in the area was determined; the co-effects of these potentially toxic materials, and key factors and pathways affecting nitrogen functions were further explored. Significant correlations between fibre- and film-shaped microplastics and phthalate esters were detected in the soils from the plateau. Copper, lead, cadmium and di-n-octyl phthalate detected significantly affected nitrogen cycling-related functional microorganisms. The co-existence of di-n-octyl phthalate and copper in soils synergistically stimulated the expression of denitrification microorganisms nirS gene and "nitrate_reduction". Additionally, di-n-octyl phthalate and dimethyl phthalate more significantly affected the variation of nitrogen cycling-related functional genes than the number of microplastics. In a dimethyl phthalate- and cadmium-polluted area, nitrogen cycling-related functional genes, especially nirK gene, were more sensitive and stressed. Overall, phthalate esters originated from microplastics play a key role in nitrogen cycling-related functions than microplastics themselves, moreover, the synergy between di-n-octyl phthalate and copper strengthen the expression of denitrification functions.
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Desnitrificação , Microplásticos , Microbiologia do Solo , Poluentes do Solo , Desnitrificação/efeitos dos fármacos , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo , Tibet , Microplásticos/toxicidade , Plastificantes/toxicidade , Plastificantes/metabolismo , Microbiota/efeitos dos fármacos , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/metabolismo , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Metais Pesados/toxicidadeRESUMO
Electronic waste (e-waste) dismantling and dumpsite processes are major sources of organophosphate flame retardant and plasticiser emissions and may pose potentially adverse effects on environment and human health. In 20 outdoor dust and 49 soil samples collected from four e-waste dismantling and three e-waste dumpsites in two States of Nigeria (Lagos and Ogun), we identified 13 alternative plasticisers (APs), 7 legacy phthalate plasticisers (LPs), and 17 organophosphorus flame retardants (OPFRs) for the first time in African e-waste streams. In the samples from dismantling sites, the range (median) concentrations of ∑13APs, ∑7LPs, and ∑17OPFRs were 11-2747 µg/g (144 µg/g), 11-396 µg/g (125 µg/g), and 0.2-68 µg/g (5.5 µg), in dust respectively and 1.8-297 µg/g (55 µg/g), 1.3-274 µg/g (48.5 µg/g), and 1.6-62 µg/g (1.6 µg/g), in soil respectively. Results for soil samples from e-waste dumpsites were (6.6-195 µg/g (23.7 µg/g), 6.0-295 µg/g (54.8), and 0.4-42.3 µg/g (9.0 µg/g) for ∑13APs, ∑7LPs, and ∑17OPFRs respectively. Overall, concentrations of APs were significantly higher at the dismantling sites (p = 0.005) compared to dumpsites, levels of LPs were higher at dismantling sites but not significant, while OPFR concentrations were significantly higher in dumpsite samples (p = 0.005). Plasticisers were found to be major contributors to pollution at e-waste dismantling sites, while OPFRs were associated with both automobile dismantling and e-waste dumpsite processes. Following particle size fractionation of selected soil samples, higher concentrations of targeted compounds were observed in the smaller mesh (180 µm) soil sieve fraction. For dust, the total median estimated daily intake via ingestion and dermal adsorption (EDIing and EDIderm) ranged from 43 to 74 ng/kg bw/day and 0.4-0.7 ng/kg bw/day, respectively. Correspondingly, 4.6-45 ng/kg bw/day and 0.015-0.57 ng/kg bw/day were the values found for soil, respectively. According to these results, the targeted chemicals do not appear to pose a non-carcinogenic risk to e-waste workers through ingestion or dermal contact of bio-accessible fractions of the chemicals. Human biomonitoring campaigns are recommended in the Nigerian e-waste environment considering the elevated concentration levels found for the majority of targeted compounds and that risk parameters required for exposure assessment were only available for a limited number of compounds.
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Niclosamide (NCL) is repurposed to treat inflammatory bowel disease due to its anti-inflammatory properties and potential to reduce oxidative stress. This therapeutic activity remains challenging if administered directly due to its low solubility and high recrystallization tendency in gastric pH. Solid dispersions using pH-dependent polymer will be a better idea to improve the solubility, dissolution and targeted delivery at the colon. Hot melt extrusion was used to formulate a solid dispersion with 30% NCL utilising hydroxypropyl methylcellulose acetate succinate as a pH-dependent polymer. In vitro drug release studies revealed formulation (F1) containing 10%w/w Tween 80 showed minimal release (2.06%) at the end of 2 h, followed by 47.87% and 82.15% drug release at 6 h and 14 h, respectively, indicating the maximum amount of drug release in the colon. The drug release from the formulations containing no plasticiser and 5%w/w plasticiser was comparable to the pure crystalline drug (approximately 25%). Solid-state analysis confirmed particle conversion of crystalline NCL to amorphous form, and the optimised formulation was stable for 6 months without significant changes in dissolution profile. In contrast to pure NCL, the F1 formulation substantially reduced the disease activity index, colonic inflammation, histological alterations and oxidative damage in colitis mice. These findings reveal that the prepared formulation can potentially deliver the drug locally at the colon, making it an effective tool in treating ulcerative colitis.
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Colite Ulcerativa , Polímeros , Camundongos , Animais , Composição de Medicamentos , Niclosamida/farmacologia , Colite Ulcerativa/tratamento farmacológico , Solubilidade , Preparações Farmacêuticas , Concentração de Íons de HidrogênioRESUMO
Honey is a natural product extensively consumed in the world for its nutritional and healthy properties. However, residues of pesticides and environmental contaminants can compromise its quality. For this reason, the physicochemical parameters, and the organic contamination of monofloral and multifloral honey from three regions of Algeria (Tiaret, Laghouat, and Tindouf) were monitored to evaluate the quality of the honey and its safety for consumers. In general, the results obtained from the physicochemical analyses were in line with the EU standards. In terms of contamination, pesticides authorised and used in Algerian agriculture (metalaxyl-M and cyromazine), as well as a banned pesticide (carbaryl), were found in almost all the samples. However, only the concentration of cyromazine was higher than the relative EU maximum residue levels. PCB 180, PCB 189, anthracene, fluorene, and phenanthrene were mainly detected. All the honey shows traces of DiBP, DBP, DEHP, and DEHT, but no traces of bisphenols were found. Moreover, according to the dietary exposure assessment, a small amount of Algerian honey can be safely consumed. Overall, the data from this study should motivate the Algerian government to enhance their monitoring activities in beekeeping and to find solutions for implementing more sustainable agricultural practices harmonising with international legislation.
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Contamination of water systems with endocrine disrupting chemicals (EDCs) is becoming a major public health concern due to their toxicity and ubiquity. The intrusion of EDCs into water sources and drinking water has been associated with various adverse health effects on humans. However, there is no comprehensive overview of the occurrence of EDCs in Malaysia's water systems. This report aims to describe the occurrence of EDCs and their locations. Literature search was conducted electronically in two databases (PubMed and Scopus). A total of 41 peer-reviewed articles published between January 2000 and May 2021 were selected. Most of the articles dealt with pharmaceuticals (16), followed by pesticides (7), hormones (7), mixed compounds (7), and plasticisers (4). Most studies (40/41) were conducted in Peninsular Malaysia, with 60.9% in the central region and almost half (48.8%) in the Selangor State. Only one study was conducted in the northern region and East Malaysia. The Langat River, the Klang River, and the Selangor River were among the most frequently studied EDC-contaminated surface waters, while the Pahang River and the Skudai River had the highest concentrations of some of the listed compounds. Most of the risk assessments resulted in a hazard quotient (HQ) and a risk quotient (RQ) < 1, indicating negligible health risk, except for ciprofloxacin and dexamethasone, which had a potential human health risk (HQHH) > 1 in the Selangor River. An RQ > 1 for combined pharmaceuticals was found in Putrajaya tap water. Overall, this work provides a comprehensive overview of the occurrence of EDCs in Malaysia's water systems. The findings from this review can be used to mitigate risks and strengthen legislation and policies for safer drinking water.
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Água Potável , Disruptores Endócrinos , Poluentes Químicos da Água , Humanos , Poluentes Químicos da Água/análise , Disruptores Endócrinos/análise , Malásia , Monitoramento Ambiental/métodos , Rios/química , Preparações FarmacêuticasRESUMO
Microplastics are present in the environment, in drinking water, in human blood and there is evidence of nanoplastics in tap water. The objective of this work was to analyze the possibility of hemodialysis patients being contaminated by micro and nanoplastics (MNPs) during dialysis treatment. The motivation for this investigation is the fact that hemodialysis patients use about 300-600 L of drinking water per week, which may be contaminated by MNPs. A literature review, a field investigation in a London hospital and an estimation of MNPs intake in patients were carried out. The results showed potential points of risk of contamination of patients by MNPs in hemodialysis. It was also estimated that for a filtration efficiency of 99 % for MNPs, the amount of microplastics that can penetrate the kidneys of patients is 0.0021-3768 particles/week. The assessment concludes that hemodialysis patients are at high risk of MNP contamination.
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Água Potável , Microplásticos , Humanos , Radar , Plásticos , Diálise RenalRESUMO
Phthalate esters (PAEs) adversely affect the human endocrine and reproductive systems. These chemical toxic compounds are used as plasticizers, in particular to improve the mechanical properties of different food packing materials. Daily food consumption is the predominant source of exposure for PAEs, especially for infants. In this study, residue profiles and levels for eight PAEs were determined in 30 infant (stage I, II and special A and B) formulas of 12 brands in Turkey and health risk assessments were performed. The average level of PAEs were different for each formula group and packing type except for BBP (p < 0.01). The highest average mean level of PAEs was detected in paperboard type packing, while the lowest average mean level of PAEs was detected in metal can type packing. The highest average level of PAEs detected was DEHP in special formulas (22.1 ng g-1). The average hazard quotient (HQ) value was calculated as 8.43 × 10-5-8.94 × 10-5 for BBP, 1.49 × 10-3-1.58 × 10-3 for DBP, 2.06 × 10-2-2.18 × 10-2 for DEHP, and 7.21 × 10-4-7.65 × 10-4 for DINP. The average HI values were calculated as 2.29 × 10-2 for 0-6 months old infants, 2.39 × 10-2 for 6-12 months old infants, and 2.43 × 10-2 for 12-36 months old infants. These calculated results show that commercial infant formulas were a source of exposure to PAEs but did not present a significant health risk.
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Dietilexilftalato , Ácidos Ftálicos , Lactente , Humanos , Fórmulas Infantis , Turquia , Ácidos Ftálicos/análise , Ésteres/análise , Dibutilftalato/análise , ChinaRESUMO
Phthalates and other plasticisers are extensively used in medical devices (MD) from which they can leach out and lead to potential multiple problems for the patients. This exposure is a major issue because it is associated with reproductive and neurodevelopment disorders. The Neonatal Intensive Care Units (NICU) population is at high risk due to the daily intensive medical interventions, the reduced ability of newborns to remove these contaminants and their higher sensitivity to endocrine disruptors. We conducted a multicentric biomonitoring study to assess and compare the urinary levels of DEHP (di-(2-ethylhexyl)phthalate), DEHTP (di-(2-ethylhexyl)terephthalate) and TEHTM (tri-(2-ethylhexyl)trimellitate) metabolites as biomarkers of this exposure during and after the newborns' stay in NICU. Daily urinary samples were collected in NICU and at discharge from the hospital for each patient. MD sources and exposure factors were also investigated. 508 urinary samples from 97 patients enrolled in centres 1 and 2 (C1/C2) were collected. The exposure of newborns to DEHP was greater than that of DEHTP and TEHTM, with a median concentration of DEHP metabolites (C1:195.63 ng/mL;C2:450.87 ng/mL) respectively 5 to 10 times higher and 57 to 228 times higher than the median concentrations of DEHTP and TEHTM metabolites. The urinary concentrations of DEHP and TEHTM metabolites were significantly lower at discharge than in NICU, with a 18-and 35-fold decrease for DEHP and a 4 and 8-fold decrease for TEHTM, respectively for C1 and C2, but were similar for DEHTP metabolites. MD used for respiratory assistance, infusion therapy,enteral nutrition and transfusion were the main sources of exposure. Smaller gestational age and body weight significantly increased the newborns' exposure. The elevated levels of DEHP metabolites in NICU patients are still alarming. Additional efforts are necessary to promote its substitution in MD by possibly safer alternatives such as TEHTM and DEHTP, particularly when used for the care of newborns.
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Disruptores Endócrinos , Unidades de Terapia Intensiva Neonatal , Ácidos Ftálicos , Plastificantes , Humanos , Recém-Nascido , Ácidos Ftálicos/análise , Plastificantes/análise , Exposição Ambiental , Disruptores Endócrinos/análise , Biomarcadores/urina , Dietilexilftalato/urinaRESUMO
The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids was requested by the European Commission to re-evaluate the risks to public health related to the presence of plasticisers such as phthalates, structurally similar substances and replacement substances, as a consequence of migration from food contact materials (FCMs). As the first part of the two-part mandate, EFSA was tasked with identifying and prioritising those plasticisers used in FCMs that may warrant further data collection and eventual risk assessment. Close collaboration with the European Chemicals Agency (ECHA) was requested in the mandate. Substances potentially used as plasticisers were identified using Annex II of the mandate, ECHA's PLASI inventory, the Plastics Regulation and the Regenerated Cellulose Film Directive, the ECHA database, the ECHA grouping approach, and consultation with the Member States. Only substances authorised for FCMs at EU or at national level were prioritised. Five substances classified either as carcinogenic, mutagenic, toxic to reproduction Cat. 1 (under CLP) or as endocrine disruptors, persistent, bioaccumulative and toxic, very persistent/very bioaccumulative (under REACH) were placed into an 'exclusion group'. Prioritisation was based on the date of the most recent risk assessment in the context of FCM, with substances assessed before 2001 being placed in the high-priority group, substances assessed between 2001 and 2011 in the medium-priority group and substances assessed after 2011 in the low-priority group. For the EU stream, the 76 substances were split into 59 high-, 14 medium- and 3 low-priority substances. For the nationally authorised stream, the split of the 72 substances is 66, 3 and 3, respectively. The outcome of follow-up calls for data in support of the exposure assessment will be used for a final ranking.
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Phthalates are a group of phthalic acid esters used as plasticisers in a large number of products to improve their flexibility, softness, and extensibility. Their wide use in medical devices, however, raises a lot of concern, as they can enter the organism and have toxic effects on human liver, thyroid, kidneys, lungs, reproductive, endocrine, nervous, and respiratory system and are associated with asthma, obesity, autism, and diabetes. The aim of this review is to summarise current knowledge about phthalate migration from medical devices during different medical procedures and possible impact on patient health. It also looks at alternative plasticisers with supposedly lower migration rates and safer profile. Not enough is known about which and how many phthalates make part of medical devices or about the health impacts of alternative plasticisers or their migration rates.
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Ácidos Ftálicos , Exposição Ambiental/efeitos adversos , Humanos , Ácidos Ftálicos/toxicidade , ReproduçãoRESUMO
Electronic waste (WEEE; from TV screens to electric toothbrushes) is one of the fastest growing waste streams in the world. Prior to recycling, e-waste components (metals, wood, glass, etc.) are processed by shredding, grinding and chainsaw cutting. These activities generate fine and ultrafine particle emissions, containing metals as well as organics (e.g., flame retardants), which have high potential for human health impacts as well as for environmental release. In this work, release of fine and ultrafine particles, and their exposure impacts, was assessed in an e-waste recycling facility under real-world operating conditions. Parameters monitored were black carbon, particle mass concentrations, ultrafine particles, and aerosol morphology and chemical composition. Potential health impacts were assessed in terms of cytotoxicity (cell viability) and oxidative stress (ROS) on <2 µm particles collected in liquid suspension. Environmental release of WEEE aerosols was evidenced by the higher particle concentrations monitored outside the facility when compared to the urban background (43 vs.11 µgPM2.5/m3, respectively, or 2.4 vs. 0.2 µgCa/m3). Inside the facility, concentrations were higher in the top than on the ground floor (PM2.5 = 147 vs. 78 µg/m3, N = 15.4 ∗ 104 vs. 8.7 ∗ 104/cm3, BC = 12.4 vs. 7.2 µg/m3). Ventilation was a key driver of human exposure, in combination with particle emissions. Key chemical tracers were Ca (from plastic fillers) and Fe (from wiring and other metal components). Y, Zr, Cd, Pb, P and Bi were markers of cathode TV recycling, and Li and Cr of grinding activities. While aerosols did not evidence cytotoxic effects, ROS generation was detected in 4 out of the 12 samples collected, associated to the ultrafine fraction. We conclude on the need for studies on aerosol emissions from WEEE facilities, especially in Europe, due to their demonstrable environmental and human health impacts and the rapidly growing generation of this type of waste.
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Resíduo Eletrônico , Retardadores de Chama , Aerossóis/análise , Resíduo Eletrônico/análise , Monitoramento Ambiental , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Humanos , Metais/toxicidade , Material Particulado/análise , Espécies Reativas de OxigênioRESUMO
This article presents the results of research on the effect of plasticisers made based on four different compounds-melamine (M), naphthalene (NF), acrylic polymers (AP) and polycarboxylic ethers (PC)-added to the tested mixes in the amount of 2% of the fly ash (FA). The influence of superplasticisers (SPs) on the consistency of the fresh concrete was investigated using a flow table and a penetrometer, and the air voids content was determined by means of a porosimeter. Additionally, the influence of plasticisers on the viscosity of the paste was investigated using a rheometer. Hardened mortar that matured under two different conditions was also tested at elevated and room temperatures. The tested properties were 7-, 28- and 90-days compressive strength and internal microstructure viewed under a microscope. NF had the greatest viscosity-reducing effect while it increased the air void volume in the mix at the same time. The highest early and late strengths were obtained after curing in elevated temperature samples with an acrylic-polymer-based superplasticiser. However, the increased curing temperature of the samples only influenced the early strength results. Its effect was not visible after 90 days. The AP addition also had a significant impact on improving the consistency of the mixture. The addition of plasticisers did not affect the microstructure of the specimens.
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Phthalates are one of many chemical compounds that are used as plasticisers. Packaging can transfer plasticisers to the surfaces of foods or other materials. A recent study suggested a link between fast food consumption and increased urine phthalate metabolites even though phthalates are most commonly found in food contact materials made of PVC while fast food packaging is most commonly composed of paper and paper board. Phthalates in PVC are usually present in percent concentrations. In non-PVC food contact materials, such as paper or paperboard, the concentrations, if any, are expected to be significantly lower which can greatly impact the analytical method used for their determination. Due to the widespread use of plasticised PVC in many commercial applications, background concentrations of phthalates are a concern for trace concentration analyses and background contamination must be avoided when performing these analyses. A glassware cleaning method was developed and a solvent extraction with dichloromethane and hexane was used to extract phthalates from paper-based food packaging. The extracts were then analysed using a GC-MS/MS. The minimum reporting concentrations for the method were determined to be 0.10-0.40 µg/g depending on the phthalate investigated. Phthalate concentrations in several different non-PVC printed and unprinted packaging are presented. Of the 54 packaging samples tested, 10 samples contained no reportable concentrations of any of the 6 phthalates investigated. Of those that were reportable, all measured lower than 10 µg/g and in fact, most had concentrations less than 1 µg/g. These data demonstrate that phthalates from fast food packaging do not significantly contribute to overall consumer exposure.
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Contaminação de Alimentos/análise , Ácidos Ftálicos/análise , Plastificantes/análise , Fast Foods , Embalagem de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/química , Humanos , Cloreto de Metileno/química , Papel , Extração em Fase Sólida , Estados UnidosRESUMO
The environmental occurrence, fate and ecotoxicity of emerging contaminants (ECs) has been the subject of increasing research, policy and public concern over the past two decades. While a wide range of publications have examined the environmental persistence and sediment/soil interactions of ECs following their discharge into aquatic environments, the extent to which ECs are sequestered in estuarine sediments, and the impact of this on their environmental persistence and supply to the ocean, in comparison remains unclear. This Article examines the environmental concentrations of seven, relatively water-soluble and environmentally mobile, ECs (including pharmaceuticals, perfluoroalkyl compounds, and plasticisers) in dated intertidal saltmarsh cores from two contrasting estuarine sites in the southern U.K. (one heavily urbanised/industrial, the other non-urbanised). Mean sediment EC concentrations are similar in both estuarine systems (in the range 0.1 (acetaminophen) to 17 (4-hydroxyacetophenone) ng/g dry weight). Despite their variable reported Log Kow values (from ca. 0.5 to > 7), the ECs are all apparently mobile in the marsh systems studied, and where subsurface concentration maxima are present these most likely relate to local flushing or diffusive processes and cannot be clearly linked to likely input trends or changes in sediment geochemistry (including sedimentary organic carbon content). The "estuarine filter" here, at least with respect to intertidal saltmarsh sediments, shows reduced potential to sequester the seven ECs examined and mediate their supply to coastal and shelf environments.
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Fluorocarbonos , Preparações Farmacêuticas , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Poluentes Químicos da Água/análiseRESUMO
Interest is growing in "smart" vaginal microbicides as a strategy to protect women from sexual transmission of human immunodeficiency virus (HIV). The concept is based on the development of products featuring low drug release in acidic media such as vaginal fluid but switch to a fast release profile when the medium becomes neutral or slightly alkaline. This mimics the surge in pH occurring in the vagina after sexual intercourse due to the seminal fluid. Semen is the main vehicle for HIV-1, and increasing antiretroviral drug levels in the vagina upon ejaculation may contribute to enhanced protection against viral sexual transmission. This work explores the use of different pharmaceutical-grade methacrylic acid-based polymers (Eudragitâ RL, RS, L and S) for developing vaginal films allowing the pH-dependant release of the antiretroviral drug tenofovir (TFV). Eudragitâ L 100 and Eudragitâ S 100, containing triethyl citrate as plasticiser, proved to be suitable for manufacturing films with optimal dual in vitro drug-release behaviour. TFV-release can be sustained for several days after film administration and all the drug is released in a few hours in conditions simulating ejaculation. The films' mechanical properties were also deemed suitable for comfortable vaginal administration. Two optimized films were further assessed using HEC-1-A and Ca Ski cell monolayer models and were found to possess favourable drug permeability profiles and drug levels associated to cell monolayer as compared to free TFV. Overall, pH-dependant films containing tenofovir may constitute promising candidates for "smart" vaginal microbicides to protect women from sexual HIV transmission.
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Fármacos Anti-HIV , HIV-1 , Preparações Farmacêuticas , Profilaxia Pré-Exposição , Administração Intravaginal , Fármacos Anti-HIV/farmacologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Metacrilatos , Polímeros , VaginaRESUMO
This review is conceived as a guide for material science researchers and conservators aiming to face the problem of deterioration of contemporary artworks entirely or partially made of plastics. It initially illustrates the analytical approaches for identifying polymeric material components in 3D art objects, such as sculptures and installations, and provides a perspective of their limits and advantages. Subsequently, the methodologies used for studying the deterioration of contemporary art plastics are reviewed, emphasising the main effects of the different types of degradation (i.e., migration of additives, oxidation and hydrolysis) and suggesting the appropriate techniques for their detection. Finally, the application of artificial ageing tests is critically assessed. All the concepts are elaborated through case studies and examples.
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The production and use of the plasticisers Hexamoll® DINCH (di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate) and DPHP (di-(2-propylheptyl) phthalate) have increased after both chemicals were introduced into the market in the early 2000s as substitutes for restricted high molecular weight phthalates. During the population representative German Environmental Survey (GerES) of Children and Adolescents (GerES V, 2014-2017), we collected urine samples and measured the concentrations of DINCH and DPHP metabolites in 2228 and in a subsample of 516 participants, respectively. We detected DINCH and DPHP metabolites in 100% and 62% of the 3-17 years old children and adolescents, respectively. Geometric means of DINCH metabolites were 2.27 µg/L for OH-MINCH, 0.93 µg/L for oxo-MINCH, 1.14 µg/L for cx-MINCH and 3.47 µg/L for DINCH (Σ of OH-MINCH + cx-MINCH). Geometric means of DPHP metabolites were 0.30 µg/L for OH-MPHP, 0.32 µg/L for oxo-MPHP and 0.64 µg/L for DPHP (Σ of OH-MPHP + oxo-MPHP). The 3-5 years old children had almost 3-fold higher DINCH biomarkers levels than adolescents (14-17 years). Higher concentrations of DPHP biomarkers among young children only became apparent after creatinine adjustment. Urinary levels of DINCH but not of DPHP biomarkers were associated with the levels of the respective plasticisers in house dust. When compared to HBM health-based guidance values, we observed no exceedance of the HBM-I value of 1 mg/L for DPHP (Σ of OH-MPHP + oxo-MPHP). However, 0.04% of the children exceeded the health based guidance value HBM-I of 3 mg/L for DINCH (Σ of OH-MINCH + cx-MINCH). This finding shows that even a less toxic replacement of restricted chemicals can reach exposures in some individuals, at which, according to current knowledge, health impacts cannot be excluded with sufficient certainty. In conclusion, we provide representative data on DINCH and DPHP exposure of children and adolescents in Germany. Further surveillance is warranted to assess the substitution process of plasticisers, and to advise exposure reduction measures, especially for highly exposed children and adolescents. Providing the results to the European HBM Initiative HBM4EU will support risk assessment and risk management not only in Germany but also in Europe.