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1.
Adv Ther ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775925

RESUMO

INTRODUCTION: Vasomotor symptoms (VMS), the characteristic symptoms of menopausal transition, are often the primary reason women seek treatment. Current treatment options for VMS include fezolinetant, a nonhormonal, selective neurokinin 3 receptor antagonist. This study aimed to define a clinically meaningful threshold for reduction of moderate-to-severe VMS in postmenopausal women treated with fezolinetant and then apply it in a responder analysis of the pooled trial data. METHODS: This analysis pooled data from two identical phase 3, double-blind, placebo-controlled studies that randomized women with moderate-to-severe VMS to once-daily fezolinetant 30 mg, 45 mg, or placebo (SKYLIGHT 1 and 2). The frequency of VMS was collected daily using an electronic diary. Patients completed the Patient Global Impression of Change in VMS (PGI-C VMS) instrument, which assessed changes in hot flushes/night sweats at weeks 4 and 12 compared with baseline using a seven-point Likert scale. VMS frequency data were anchored to PGI-C VMS data; the anchor level for meaningful within-patient change in PGI-C VMS was "moderately better." RESULTS: In the pooled population (N = 1022), the mean (standard deviation) estimated thresholds for a meaningful within-patient change in moderate-to-severe VMS frequency were - 5.73 (3.47) at week 4 and - 6.20 (5.18) at week 12. Applying the thresholds for meaningful within-patient change to responder analyses ("missing as non-responder" imputation method) indicated a favorable clinical benefit: greater proportions of responders were observed in the fezolinetant 30-mg and 45-mg groups compared with placebo at week 4 (odds ratio range 2.48-2.91; P < 0.001) and week 12 (odds ratio range 1.908-2.68; P < 0.001). CONCLUSION: PGI-C VMS is sensitive to change and correlates with VMS frequency: a reduction of approximately six VMS episodes per day from baseline to week 12 was meaningful at the individual patient level. Fezolinetant provides a meaningful clinical benefit for women with moderate-to-severe VMS associated with menopause and represents an important nonhormonal treatment option. TRIAL REGISTRATION NUMBER: NCT04003155 and NCT04003142.

2.
Chem Commun (Camb) ; 60(35): 4703-4706, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38596847

RESUMO

The reaction of the tetrahedral complex [{CpMo(CO)2}2(µ,η2-AsSb)] with CuI and AgI salts is presented which gives unprecedented neutral and cationic supramolecular aggregates featuring mixed As/Sb-donor molecules as ligands/linkers between metal ions.

3.
Dalton Trans ; 52(48): 18137-18142, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38031896

RESUMO

The reaction of the Ag(I) dimer [Ag2(η2-A)2(µ,η1:η1-A)2][TEF]2 (A = [{CpMo(CO)2}2(µ,η2-P2)]) possessing labile η2-coordinated P2 ligands with the organometallic dipnictogen compounds [{CpMo(CO)2}2(µ,η2-EE')] (E = E' = As, Sb; E = P, E' = As, Sb) represents a facile synthetic route towards unprecedented heteroleptic pnictogen-rich supramolecular complexes. This method can also be extended to the analogous Cu(I) dimer and is studied by DFT computations.

4.
Environ Int ; 180: 108161, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37758599

RESUMO

Food contact materials (FCMs) and food contact articles are ubiquitous in today's globalized food system. Chemicals migrate from FCMs into foodstuffs, so called food contact chemicals (FCCs), but current regulatory requirements do not sufficiently protect public health from hazardous FCCs because only individual substances used to make FCMs are tested and mostly only for genotoxicity while endocrine disruption and other hazard properties are disregarded. Indeed, FCMs are a known source of a wide range of hazardous chemicals, and they likely contribute to highly prevalent non-communicable diseases. FCMs can also include non-intentionally added substances (NIAS), which often are unknown and therefore not subject to risk assessment. To address these important shortcomings, we outline how the safety of FCMs may be improved by (1) testing the overall migrate, including (unknown) NIAS, of finished food contact articles, and (2) expanding toxicological testing beyond genotoxicity to multiple endpoints associated with non-communicable diseases relevant to human health. To identify mechanistic endpoints for testing, we group chronic health outcomes associated with chemical exposure into Six Clusters of Disease (SCOD) and we propose that finished food contact articles should be tested for their impacts on these SCOD. Research should focus on developing robust, relevant, and sensitive in-vitro assays based on mechanistic information linked to the SCOD, e.g., through Adverse Outcome Pathways (AOPs) or Key Characteristics of Toxicants. Implementing this vision will improve prevention of chronic diseases that are associated with hazardous chemical exposures, including from FCMs.


Assuntos
Contaminação de Alimentos , Doenças não Transmissíveis , Humanos , Contaminação de Alimentos/análise , Saúde Pública , Embalagem de Alimentos , Alimentos , Substâncias Perigosas/toxicidade
5.
Chem Commun (Camb) ; 59(75): 11192-11195, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37650148

RESUMO

The reaction of the low-coordinate quadruply-bonded dimolybdenum complex Mo2[µ,κ2-PhB(N-2,6-iPr2C6H3)2]2 (1) with Cp*Fe(η5-E5) (E = P, As) gives two trinuclear species Cp*Fe(µ3,η5:2:2-E5)Mo2[µ,κ2-PhB(N-2,6-iPr2C6H3)2]2 (E = P (4) and As (5)). 4 undergoes facile isomerisation upon heating to give Cp*FeMo2[κ2-PhB(N-2,6-iPr2C6H3)2](µ3,κ:κ:η2-P2)[µ3,κ:κ:η3κ-P3PhB(N-2,6-iPr2C6H3)2] (6), where the FeMo2P5 core motif displays a cubane-like structure.

6.
Chemistry ; 29(61): e202301974, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37493637

RESUMO

The reactivity of the mixed dipnictogen complexes [{CpMo(CO)2 }2 (µ,η2 : 2 -PE)] (E=P, As, Sb) towards different group 14 electrophiles is reported. The resulting library of cationic compounds [{CpMo(CO)2 }2 (µ,η2 : 2 -EPR)]+ (R=Mes (2,4,6-C6 H2 Me3 ), CH3 , CPh3 , SnMe3 ) represents formally inorganic diazonium homologs which are stabilized by transition metal units. Modifying the steric and electronic properties of the electrophile drastically impacts the respective P-R bond lengths and is accompanied by increasing (SnMe3 >CPh3 >CH3 ) dynamic behavior in solution. In contrast to the well-studied organic analogs, the prepared compounds are stable at room temperature. The subsequent reaction of the model substrate [{CpMo(CO)2 }2 (µ,η2 : 2 -P2 Me)][OTf] ([OTf]- =[CF3 SO3 ]- ) with different N-heterocyclic carbenes (NHCs) leads to an addition at the unsubstituted P atom which is also predicted by computational methods. NMR spectroscopy confirms the formation of two isomers sync/gauche-[{CpMo(CO)2 }(µ,η2 : 1 -P(NHC)PMe){CpMo(CO)2 }][OTf]. X-ray crystallographic characterization and additional DFT calculations shed light on the spatial arrangement as well as on the possible formation pathways of the isomers.

8.
Cardiol Ther ; 12(2): 371-391, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37138193

RESUMO

INTRODUCTION: Treatment adherence and persistence impact the effectiveness of edoxaban for the prevention of thromboembolism in patients with atrial fibrillation (AF). The objective of this analysis was to assess adherence and persistence of edoxaban vs. other non-vitamin K antagonist oral anticoagulants (NOACs) and vitamin K antagonists (VKAs). METHODS: Utilizing a German claims database, adults with AF with the first pharmacy claim identified for edoxaban, apixaban, dabigatran, rivaroxaban, or VKAs from January 2013 to December 2017 were included in a propensity score-matched analysis. The first pharmacy claim was the index claim. Adherence (i.e., proportion of days covered [PDC]) and persistence (proportion of patients who continued therapy) were compared between edoxaban and other therapies. Patients receiving once-daily (QD) vs. twice-daily (BID) NOAC were also analyzed. RESULTS: Overall, 21,038 patients were included (1236 edoxaban, 6053 apixaban, 1306 dabigatran, 7013 rivaroxaban, and 5430 VKA). After matching, baseline characteristics were well balanced across cohorts. Adherence was significantly higher for edoxaban vs. apixaban, dabigatran, and VKAs (all P < 0.0001). Significantly more edoxaban patients continued therapy vs. rivaroxaban (P = 0.0153), dabigatran (P < 0.0001), and VKAs (P < 0.0001). Time to discontinuation was significantly longer for edoxaban vs. dabigatran, rivaroxaban, and VKAs (all P < 0.0001). More patients receiving NOACs QD had a PDC ≥ 0.8 compared with those receiving NOACs BID (65.3 vs. 49.6%, respectively; P < 0.05); persistence rates were comparable between QD and BID groups. CONCLUSIONS: Patients with AF receiving edoxaban had significantly higher adherence and persistence compared with those receiving VKAs. This trend was also seen in NOAC QD regimens vs. NOAC BID regimens for adherence. These results provide insight into how adherence and persistence may contribute to the effectiveness of edoxaban for stroke prevention in patients with AF in Germany.

9.
Chem Sci ; 14(18): 4769-4776, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37181779

RESUMO

Insertion and functionalization of gallasilylenes [LPhSi-Ga(Cl)LBDI] (LPh = PhC(NtBu)2; LBDI = [{2,6-iPr2C6H3NCMe}2CH]) into the cyclo-E5 rings of [Cp*Fe(η5-E5)] (Cp* = η5-C5Me5; E = P, As) are reported. Reactions of [Cp*Fe(η5-E5)] with gallasilylene result in E-E/Si-Ga bond cleavage and the insertion of the silylene in the cyclo-E5 rings. [(LPhSi-Ga(Cl)LBDI){(η4-P5)FeCp*}], in which the Si atom binds to the bent cyclo-P5 ring, was identified as a reaction intermediate. The ring-expansion products are stable at room temperature, while isomerization occurred at higher temperature, and the silylene moiety further migrates to the Fe atom, forming the corresponding ring-construction isomers. Furthermore, reaction of [Cp*Fe(η5-As5)] with the heavier gallagermylene [LPhGe-Ga(Cl)LBDI] was also investigated. All the isolated complexes represent rare examples of mixed group 13/14 iron polypnictogenides, which could only be synthesized by taking advantage of the cooperativity of the gallatetrylenes featuring low-valent Si(ii) or Ge(ii) and Lewis acidic Ga(iii) units/entities.

10.
Chemistry ; 29(24): e202300340, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36809680

RESUMO

A missing family of the extremely air sensitive tripentelyltrielanes was discovered. Their stabilisation was achieved by using the bulky NHC IDipp (NHC=N-heterocyclic carbene, IDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene). The tripentelylgallanes and tripentelylalanes IDipp ⋅ Ga(PH2 )3 (1 a), IDipp ⋅ Ga(AsH2 )3 (1 b), IDipp ⋅ Al(PH2 )3 (2 a) and IDipp ⋅ Al(AsH2 )3 (2 b) were synthesised by salt metathesis of IDipp ⋅ ECl3 (E=Al, Ga, In) with alkali metal pnictogenides such as NaPH2 /LiPH2 ⋅ DME and KAsH2 , respectively. Moreover, the detection of the first NHC-stabilised tripentelylindiumane IDipp ⋅ In(PH2 )3 (3) was possible by multinuclear NMR spectroscopy. Initial investigations of the coordination ability of these compounds resulted in the successful isolation of the coordination compound [IDipp ⋅ Ga(PH2 )2 (µ3 -PH2 {HgC6 F4 }3 )] (4) by reaction of 1 a with (HgC6 F4 )3 . The compounds were characterised by multinuclear NMR spectroscopy as well as single crystal X-ray diffraction studies. Supporting computational studies highlight the electronic features of the products.

11.
Crit Rev Food Sci Nutr ; 63(28): 9425-9435, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35585831

RESUMO

Food packaging is important for today's globalized food system, but food contact materials (FCMs) can also be a source of hazardous chemicals migrating into foodstuffs. Assessing the impacts of FCMs on human health requires a comprehensive identification of the chemicals they contain, the food contact chemicals (FCCs). We systematically compiled the "database on migrating and extractable food contact chemicals" (FCCmigex) using information from 1210 studies. We found that to date 2881 FCCs have been detected, in a total of six FCM groups (Plastics, Paper & Board, Metal, Multi-materials, Glass & Ceramic, and Other FCMs). 65% of these detected FCCs were previously not known to be used in FCMs. Conversely, of the more than 12'000 FCCs known to be used, only 1013 are included in the FCCmigex database. Plastic is the most studied FCM with 1975 FCCs detected. Our findings expand the universe of known FCCs to 14,153 chemicals. This knowledge contributes to developing non-hazardous FCMs that lead to safer food and support a circular economy.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Humanos , Contaminação de Alimentos/análise , Substâncias Perigosas/análise , Bases de Dados Factuais , Plásticos
12.
Sci Rep ; 12(1): 16788, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202937

RESUMO

The resistance of hard corals to warming can be negatively affected by nitrate eutrophication, but related knowledge for soft corals is scarce. We thus investigated the ecophysiological response of the pulsating soft coral Xenia umbellata to different levels of nitrate eutrophication (control = 0.6, medium = 6, high = 37 µM nitrate) in a laboratory experiment, with additional warming (27.7 to 32.8 °C) from days 17 to 37. High nitrate eutrophication enhanced cellular chlorophyll a content of Symbiodiniaceae by 168%, while it reduced gross photosynthesis by 56%. After additional warming, polyp pulsation rate was reduced by 100% in both nitrate eutrophication treatments, and additional polyp loss of 7% d-1 and total fragment mortality of 26% was observed in the high nitrate eutrophication treatment. Warming alone did not affect any of the investigated response parameters. These results suggest that X. umbellata exhibits resistance to warming, which may facilitate ecological dominance over some hard corals as ocean temperatures warm, though a clear negative physiological response occurs when combined with nitrate eutrophication. This study thus confirms the importance of investigating combinations of global and local factors to understand and manage changing coral reefs.


Assuntos
Antozoários , Dinoflagellida , Animais , Antozoários/fisiologia , Clorofila A , Recifes de Corais , Nitratos , Compostos Orgânicos
13.
J Hazard Mater ; 437: 129167, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35897167

RESUMO

The EU Chemicals Strategy for Sustainability (CSS) aims at removing the most harmful chemicals from consumer products, including from food contact materials (FCMs). If implemented as intended, the CSS has the potential to significantly improve the protection of public health by banning the use of chemicals of concern that are carcinogenic, mutagenic, or toxic to reproduction (CMRs), or persistent and bioaccumulative, or endocrine-disrupting chemicals (EDCs) in FCMs. However, until now an overview of such food contact chemicals of concern (FCCoCs) has not been available, because the CSS is fairly recent. Therefore, we here systematically analyze the food contact chemicals listed for intentional use in FCMs and identify known FCCoCs. We present a list of 388 FCCoCs that should be phased-out from use. Of these, 352 are CMRs, four are per- and polyfluoroalkyl substances (PFAS), and 127 have empirical evidence for presence in FCMs. Importantly, 30 FCCoCs with evidence for presence are monomers of which 22 have evidence for migration into foodstuff showing that monomers in FCMs indeed become relevant for human exposure. Our findings justify moving away from a risk- towards a hazard-based approach to regulation of chemicals in FCMs.


Assuntos
Exposição Dietética/estatística & dados numéricos , Contaminação de Alimentos , Substâncias Perigosas , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , União Europeia , Alimentos , Embalagem de Alimentos , Humanos , Poluentes Orgânicos Persistentes , Saúde Pública , Reprodução
14.
Environ Sci Technol ; 56(4): 2487-2496, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35080176

RESUMO

Bisphenols and phthalates, chemicals frequently used in plastic products, promote obesity in cell and animal models. However, these well-known metabolism-disrupting chemicals (MDCs) represent only a minute fraction of all compounds found in plastics. To gain a comprehensive understanding of plastics as a source of exposure to MDCs, we characterized the chemicals present in 34 everyday products using nontarget high-resolution mass spectrometry and analyzed their joint adipogenic activities by high-content imaging. We detected 55,300 chemical features and tentatively identified 629 unique compounds, including 11 known MDCs. Importantly, the chemicals extracted from one-third of the products caused murine 3T3-L1 preadipocytes to proliferate, and differentiate into adipocytes, which were larger and contained more triglycerides than those treated with the reference compound rosiglitazone. Because the majority of plastic extracts did not activate the peroxisome proliferator-activated receptor γ and the glucocorticoid receptor, the adipogenic effects are mediated via other mechanisms and, thus, likely to be caused by unknown MDCs. Our study demonstrates that daily-use plastics contain potent mixtures of MDCs and can, therefore, be a relevant yet underestimated environmental factor contributing to obesity.


Assuntos
Adipogenia , Plásticos , Células 3T3-L1 , Adipócitos , Animais , Camundongos , Obesidade , PPAR gama , Plásticos/farmacologia
15.
J AOAC Int ; 105(2): 442-455, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34791280

RESUMO

BACKGROUND: According to Codex Alimentarius, food products containing less than 20 mg/kg gluten can be labeled as "gluten-free." Since 2002, the R5 antibody method allowed determination of gluten levels and led to a huge improvement of products available to celiac disease (CD) patients. METHOD: The R5-containing test kit RIDASCREEN® Gliadin in combination with the cocktail solution was endorsed as Codex Type 1 Method in 2006 based on a collaborative study with corn-based bread, rice-based dough, wheat starches, rice, and corn flour. In 2012, the method was approved as First Action Official MethodSM2012.01 with an "in foods" claim. For Final Action in 2016, the matrix claim was reduced to rice- and corn-based matrixes. OBJECTIVE: Therefore, R-Biopharm decided to start a collaborative study to demonstrate the wide applicability of Official Method 2012.01 for the quantitative analysis of gliadin in soy, starches, pseudo cereals, legumes, spices, juice, nut nougat crème, cream cheese, pesto, meat, vegetarian meat alternative, cookies, dessert, cake, fish, bread, candies, and potatoes. Materials for incurring were the MoniQA wheat flour and the PWG gliadin preparation. RESULTS: Gliadin levels ranged from 3.4 up to 27.4 mg gliadin per kg. The results of the collaborative study with 14 participating laboratories showed recoveries ranging from 80 to 130%. Relative reproducibility standard deviations for contaminated samples were between 9.8 and 27.7%. CONCLUSIONS: The collaborative study results confirmed that the method is accurate and suitable to measure gliadin in important gluten-free food matrixes. HIGHLIGHTS: The title and applicability statement of Official Method 2012.01 were changed as proposed.


Assuntos
Ensaio de Imunoadsorção Enzimática , Análise de Alimentos/métodos , Gliadina , Glutens , Ensaio de Imunoadsorção Enzimática/métodos , Farinha/análise , Gliadina/análise , Glutens/análise , Reprodutibilidade dos Testes , Triticum
16.
Environ Sci Technol ; 55(17): 11814-11823, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34488348

RESUMO

Plastic products contain complex mixtures of extractable chemicals that can be toxic. However, humans and wildlife will only be exposed to plastic chemicals that are released under realistic conditions. Thus, we investigated the toxicological and chemical profiles leaching into water from 24 everyday plastic products covering eight polymer types. We performed migration experiments over 10 days at 40 °C and analyzed the migrates using four in vitro bioassays and nontarget high-resolution mass spectrometry (UPLC-QTOF-MSE). All migrates induced baseline toxicity, 22 an oxidative stress response, 13 antiandrogenicity, and one estrogenicity. Overall, between 17 and 8681 relevant chemical features were present in the migrates. In other words, between 1 and 88% of the plastic chemicals associated with one product were migrating. Further, we tentatively identified ∼8% of all detected features implying that most plastic chemicals remain unknown. While low-density polyethylene, polyvinyl chloride, and polyurethane induced most toxicological endpoints, a generalization for other materials is not possible. Our results demonstrate that plastic products readily leach many more chemicals than previously known, some of which are toxic in vitro. This highlights that humans are exposed to many more plastic chemicals than currently considered in public health science and policies.


Assuntos
Plásticos , Polímeros , Humanos , Plásticos/toxicidade , Polietileno
17.
United European Gastroenterol J ; 9(9): 1039-1047, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34329537

RESUMO

BACKGROUND: Pyogenic liver abscesses (PLAs) represent potentially life-threatening abdominal conditions that require immediate diagnosis and therapy. European and American incidence figures vary between one and 15 per 100,000 per year. Structured epidemiological data for European countries are not available. OBJECTIVE: To systematically characterize the epidemiology and clinical outcome of PLA in Germany. METHODS: In representative statutory health insurance data from four million people in 2013-2019, the prevalence and incidence with clinical coding of International Statistical Classification of Diseases and Related Health Problems (ICD)-10 code K75.0 were selected (n = 1118). Furthermore, demographics, relevant comorbidities, hospitalizations, mortality and complications were determined within one year. RESULTS: The incidence of PLA was approximately seven per 100,000. The average age at diagnosis was 66 years; 65% were male. Of these, biliary disease was documented in over 60% and infectious intestinal diseases were found in 21% within the same or previous calendar year. PLA patients had high comorbidity indices. Liver transplant status, malignancies of the liver and biliary system, liver cirrhosis and pancreatitis were strongly associated. Intensive care was documented in 27% of PLA cases. Nine percent died within 12 months, most with an underlying malignant disease. CONCLUSION: Pyogenic liver abscess is a rare disease with high morbidity. Predisposing and risk factors include intestinal and biliary diseases as well as hepatic malignancies. Further research should focus on PLA therapy within prospective surveys and controlled clinical trials.


Assuntos
Abscesso Hepático Piogênico/epidemiologia , Abscesso Hepático Piogênico/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Biliares/epidemiologia , Comorbidade , Registros Eletrônicos de Saúde , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Seguro Saúde , Enteropatias/epidemiologia , Cirrose Hepática/epidemiologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Pancreatite/epidemiologia , Fatores de Risco , Adulto Jovem
18.
Environ Pollut ; 267: 115392, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32871484

RESUMO

Given the ubiquitous presence of microplastics in aquatic environments, an evaluation of their toxicity is essential. Microplastics are a heterogeneous set of materials that differ not only in particle properties, like size and shape, but also in chemical composition, including polymers, additives and side products. Thus far, it remains unknown whether the plastic chemicals or the particle itself are the driving factor for microplastic toxicity. To address this question, we exposed Daphnia magna for 21 days to irregular polyvinyl chloride (PVC), polyurethane (PUR) and polylactic acid (PLA) microplastics as well as to natural kaolin particles in high concentrations (10, 50, 100, 500 mg/L, ≤ 59 µm) and different exposure scenarios, including microplastics and microplastics without extractable chemicals as well as the extracted and migrating chemicals alone. All three microplastic types negatively affected the life-history of D. magna. However, this toxicity depended on the endpoint and the material. While PVC had the largest effect on reproduction, PLA reduced survival most effectively. The latter indicates that bio-based and biodegradable plastics can be as toxic as their conventional counterparts. The natural particle kaolin was less toxic than microplastics when comparing numerical concentrations. Importantly, the contribution of plastic chemicals to the toxicity was also plastic type-specific. While we can attribute effects of PVC to the chemicals used in the material, effects of PUR and PLA plastics were induced by the mere particle. Our study demonstrates that plastic chemicals can drive microplastic toxicity. This highlights the importance of considering the individual chemical composition of plastics when assessing their environmental risks. Our results suggest that less studied polymer types, like PVC and PUR, as well as bioplastics are of particular toxicological relevance and should get a higher priority in ecotoxicological studies.


Assuntos
Plásticos , Poluentes Químicos da Água , Animais , Daphnia , Ecotoxicologia , Microplásticos , Plásticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
19.
Environ Int ; 145: 106066, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32951901

RESUMO

Plastics contain a complex mixture of known and unknown chemicals; some of which can be toxic. Bioplastics and plant-based materials are marketed as sustainable alternative to conventional plastics. However, little is known with regard to the chemicals they contain and the safety of these compounds. Thus, we extracted 43 everyday bio-based and/or biodegradable products as well as their precursors, covering mostly food contact materials made of nine material types, and characterized these extracts using in vitro bioassays and non-target high-resolution mass spectrometry. Two-third (67%) of the samples induced baseline toxicity, 42% oxidative stress, 23% antiandrogenicity and one sample estrogenicity. In total, we detected 41,395 chemical features with 186-20,965 features present in the individual samples. 80% of the extracts contained >1000 features, most of them unique to one sample. We tentatively identified 343 priority compounds including monomers, oligomers, plastic additives, lubricants and non-intentionally added substances. Extracts from cellulose- and starch-based materials generally triggered a strong in vitro toxicity and contained most chemical features. The toxicological and chemical signatures of polyethylene (Bio-PE), polyethylene terephthalate (Bio-PET), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polylactic acid (PLA), polyhydroxyalkanoates (PHA) and bamboo-based materials varied with the respective product rather than the material. Toxicity was less prevalent and potent in raw materials than in final products. A comparison with conventional plastics indicates that bioplastics and plant-based materials are similarly toxic. This highlights the need to focus more on aspects of chemical safety when designing truly "better" plastic alternatives.


Assuntos
Plásticos , Poli-Hidroxialcanoatos , Plásticos/toxicidade
20.
Angew Chem Int Ed Engl ; 59(37): 16241-16246, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32463937

RESUMO

In a high-yield one-pot synthesis, the reactions of [Cp*M(η5 -P5 )] (M=Fe (1), Ru (2)) with I2 resulted in the selective formation of [Cp*MP6 I6 ]+ salts (3, 4). The products comprise unprecedented all-cis tripodal triphosphino-cyclotriphosphine ligands. The iodination of [Cp*Fe(η5 -As5 )] (6) gave, in addition to [Fe(CH3 CN)6 ]2+ salts of the rare [As6 I8 ]2- (in 7) and [As4 I14 ]2- (in 8) anions, the first di-cationic Fe-As triple decker complex [(Cp*Fe)2 (µ,η5:5 -As5 )][As6 I8 ] (9). In contrast, the iodination of [Cp*Ru(η5 -As5 )] (10) did not result in the full cleavage of the M-As bonds. Instead, a number of dinuclear complexes were obtained: [(Cp*Ru)2 (µ,η5:5 -As5 )][As6 I8 ]0.5 (11) represents the first Ru-As5 triple decker complex, thus completing the series of monocationic complexes [(CpR M)2 (µ,η5:5 -E5 )]+ (M=Fe, Ru; E=P, As). [(Cp*Ru)2 As8 I6 ] (12) crystallizes as a racemic mixture of both enantiomers, while [(Cp*Ru)2 As4 I4 ] (13) crystallizes as a symmetric and an asymmetric isomer and features a unique tetramer of {AsI} arsinidene units as a middle deck.

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