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1.
J Environ Sci (China) ; 145: 97-106, 2024 Nov.
Article En | MEDLINE | ID: mdl-38844327

Sediment is the ultimate sink of environmental pollutants. A total of 128 surface sediment samples were collected from 8 rivers and 3 reservoirs in Maoming City, Guangdong Province. This study assessed the content and distribution of brominated flame retardants in sediments. The acute toxicity effects of tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDs) in sediments were evaluated using Caenorhabditis elegans as model organisms. The concentration of TBBPA in sediments ranged from not detected (ND) to 12.59 µg/kg and was mainly distributed in the central area, which was affected by the emission of TBBPA from residential and factory. The concentration of HBCDs ranged from ND to 6.31 µg/kg, and the diastereoisomer distribution was consistent, showing a trend close to the South China Sea. The composition pattern of HBCDs in the surface sediments from rivers were 41.73%-62.33%, 7.89%-25.54%, and 18.76%-40.65% for α-, ß-, and γ-HBCD, respectively, and in the sediments from reservoirs were 26.15%-45.52%, 7.44%-19.23%, and 47.04%-61.89% for α-, ß-, and γ-HBCD, respectively. When the sum of concentrations of TBBPA and HBCD in sediments were above high levels, reactive oxygen species in nematodes significantly increased, resulting in an oxidative stress response. Intestinal permeability was also enhanced, causing intestinal damage. In addition, in terms of this study, TBBPA had a greater impact on biotoxicity compared to HBCDs, and more attention should be paid to the toxic effects of the river ecosystem organisms in Maoming City, Guangdong Province. This study can complement the pollution database in the study area and provide basic data for pollution control.


Caenorhabditis elegans , Environmental Monitoring , Flame Retardants , Geologic Sediments , Hydrocarbons, Brominated , Water Pollutants, Chemical , Animals , Flame Retardants/toxicity , Flame Retardants/analysis , China , Caenorhabditis elegans/drug effects , Geologic Sediments/chemistry , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Hydrocarbons, Brominated/analysis , Hydrocarbons, Brominated/toxicity , Polybrominated Biphenyls/toxicity , Polybrominated Biphenyls/analysis
2.
Environ Res ; 252(Pt 4): 119119, 2024 Jul 01.
Article En | MEDLINE | ID: mdl-38734290

Hexabromocyclododecane (HBCD), as a monitored chemical of the Chemical Weapons Convention, the Stockholm Convention and the Action Plan for New Pollutants Treatment in China, raises significant concerns on its impact of human health and food security. This study investigated enantiomer-specific biomarkers of HBCD in maize (Zea mays L.). Upon exposure to HBCD enantiomers, the maize root tip cell wall exhibited thinning, uneven cell gaps, and increased deposition on the cell outer wall. Elevated malondialdehyde (MDA) indicated lipid peroxidation, with higher mitochondrial membrane potential (MMP) inhibition in (+)-enantiomer treatments (47.2%-57.9%) than (-)-enantiomers (14.4%-37.4%). The cell death rate significantly increased by 37.7%-108.8% in roots and 16.4%-62.4% in shoots, accompanied by the upregulation of superoxide dismutase isoforms genes. Molecular docking presenting interactions between HBCD and target proteins, suggested that HBCD has an affinity for antioxidant enzyme receptors with higher binding energy for (+)-enantiomers, further confirming their stronger toxic effects. All indicators revealed that oxidative damage to maize seedlings was more severe after treatment with (+)-enantiomers compared to (-)-enantiomers. This study elucidates the biomarkers of phytotoxicity evolution induced by HBCD enantiomers, providing valuable insights for the formulation of more effective policies to safeguard environmental safety and human health in the future.


Biomarkers , Hydrocarbons, Brominated , Molecular Docking Simulation , Zea mays , Zea mays/drug effects , Zea mays/genetics , Hydrocarbons, Brominated/toxicity , Stereoisomerism , Flame Retardants/toxicity , Lipid Peroxidation/drug effects
3.
Ecotoxicol Environ Saf ; 276: 116280, 2024 May.
Article En | MEDLINE | ID: mdl-38574648

In recent years, accumulating evidence supports that occupational exposure to solvents is associated with an increased incidence of Parkinson's disease (PD) among workers. The neurotoxic effects of 1-bromopropane (1-BP), a widely used new-type solvent, are well-established, yet data on its relationship with the etiology of PD remain limited. Simultaneously, high-fat consumption in modern society is recognized as a significant risk factor for PD. However, whether there is a synergistic effect between a high-fat diet and 1-BP exposure remains unclear. In this study, adult C57BL/6 mice were fed either a chow or a high-fat diet for 18 weeks prior to 12-week 1-BP treatment. Subsequent neurobehavioral and neuropathological examinations were conducted to assess the effects of 1-BP exposure on parkinsonian pathology. The results demonstrated that 1-BP exposure produced obvious neurobehavioral abnormalities and dopaminergic degeneration in the nigral region of mice. Importantly, a high-fat diet further exacerbated the impact of 1-BP on motor and cognitive abnormalities in mice. Mechanistic investigation revealed that mitochondrial damage and mtDNA release induced by 1-BP and high-fat diet activate NLRP3 and cGAS-STING pathway- mediated neuroinflammatory response, and ultimately lead to necroptosis of dopaminergic neurons. In summary, our study unveils a potential link between chronic 1-BP exposure and PD-like pathology with motor and no-motor defects in experimental animals, and long-term high-fat diet can further promote 1-BP neurotoxicity, which underscores the pivotal role of environmental factors in the etiology of PD.


Diet, High-Fat , Dopaminergic Neurons , Hydrocarbons, Brominated , Mice, Inbred C57BL , Mitochondria , Substantia Nigra , Animals , Hydrocarbons, Brominated/toxicity , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/pathology , Mice , Substantia Nigra/drug effects , Substantia Nigra/pathology , Substantia Nigra/metabolism , Male , Mitochondria/drug effects , Mitochondria/pathology , Solvents/toxicity
4.
Int J Biol Macromol ; 268(Pt 1): 131535, 2024 May.
Article En | MEDLINE | ID: mdl-38631586

Herein, efficient degradation of hexabromocyclododecane (HBCD) and Lindane, a persistent organic pollutant using guar gum based calcium oxide doped silicon dioxide (GG-CaO@SiO2) has been reported. The nanocomposite was prepared by waste egg shell (CaO) and rice husk (SiO2) was well characterized. The maximum degradation of HBCD and Lindane were observed at 8 mg catalyst loading, neutral pH, and 2 mg L-1 of pollutant amount. The photocatalytic performance of GG-CaO@SiO2 for HBCD and Lindane photodegradation was evaluated, and it was found that the rate constant increased in the order of GG-CaO@SiO2 > CaO@SiO2 > GG. The polymeric GG-CaO@SiO2 nanocomposite showed maximum removal of both pollutants due to higher surface area (70 m2 g-1) and synergistic interactions among GG moieties. It achieved HBCD and Lindane elimination rates of 94 % and 90 % by photo-adsorptive degradation within 150 min. Meanwhile, the leaching of HBCD from expanded polystyrene (EPS) materials (0.14 ± 0.05 ppm) underwater with different time intervals and degradation of leachate HBCD were also assessed. The eradication of the pollutant manifested first-order kinetics, with the Langmuir adsorption. LC-MS analysis confirmed that GG-CaO@SiO2 effectively breaks down complex structure toxic pollutants into safer metabolites under natural sunlight exposure. The polymeric GG-CaO@SiO2 nanocomposite showed notable reusability up to ten cycle promotes sustainability.


Galactans , Hexachlorocyclohexane , Mannans , Nanocomposites , Plant Gums , Plant Gums/chemistry , Mannans/chemistry , Nanocomposites/chemistry , Galactans/chemistry , Hexachlorocyclohexane/chemistry , Silicon Dioxide/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Calcium Compounds/chemistry , Oxides/chemistry , Photolysis , Adsorption , Waste Products , Catalysis , Hydrogen-Ion Concentration , Hydrocarbons, Brominated
5.
Int J Clin Pharmacol Ther ; 62(5): 213-221, 2024 May.
Article En | MEDLINE | ID: mdl-38431832

OBJECTIVE: Irinotecan (IRI) is an anticancer drug that is frequently used to treat colorectal, gastric, and pancreatic cancers. Its side effects include cholinergic symptoms, such as diarrhea, abdominal pain, nausea, and hyperhidrosis. Anticholinergic medicines are frequently used for treatment or prophylaxis; however, the risk factors for the failure of a single prophylactic anticholinergic administration remain unclear. Moreover, an appropriate anticholinergic drug for prophylaxis remains unknown. Thus, we aimed to identify the risk factors associated with the failure of a single prophylactic dose of anticholinergic drugs for IRI-induced cholinergic symptoms and to evaluate the usefulness of multiple prophylactic doses of anticholinergic drugs. MATERIALS AND METHODS: Patients who underwent IRI treatment for colorectal, gastric, or pancreatic cancer and received prophylactic anticholinergic drugs for IRI-induced cholinergic symptoms (n = 135) were retrospectively evaluated. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for failure of a single prophylactic dose of anticholinergic drugs. We also evaluated the efficacy of multiple prophylactic anticholinergic drug administration. RESULTS: Based on univariate and multivariate analyses, colorectal cancer, female sex, and prophylactic use of scopolamine butyl bromide were identified as risk factors for failure of a single prophylactic dose of anticholinergic drugs. The efficacy of multiple prophylactic doses was confirmed to be 95% of the patients who had a single prophylactic failure due to temporary effect but symptom appearance after a certain period of time (wearing-off). CONCLUSION: We determined that colorectal cancer, female sex, and prophylactic use of scopolamine butyl bromide were risk factors associated with the failure of a single prophylactic dose of anticholinergic drugs, and that multiple prophylactic doses for wearing-off can be a promising method.


Cholinergic Antagonists , Colorectal Neoplasms , Hydrocarbons, Brominated , Humans , Female , Irinotecan/adverse effects , Retrospective Studies , Cholinergic Antagonists/adverse effects , Risk Factors , Cholinergic Agents , Butylscopolammonium Bromide , Colorectal Neoplasms/drug therapy
6.
J Mater Chem B ; 12(15): 3764-3773, 2024 Apr 17.
Article En | MEDLINE | ID: mdl-38533806

In this study, we utilized X-ray-induced photodynamic therapy (X-PDT) against triple-negative breast cancer (TNBC) cells. To achieve this, we developed a liposome delivery system that co-loaded protoporphyrin IX (PPIX) and perfluorooctyl bromide (PFOB) in a rational manner. Low-dose X-ray at 2 Gy was employed to activate PPIX for the generation of reactive oxygen species (ROS), and the co-loading of PFOB provided additional oxygen to enhance ROS production. The resulting highly toxic ROS effectively induced cell death in TNBC. In vitro X-PDT effects, including intracellular ROS generation, cell viability, and apoptosis/necrosis assays in TNBC cells, were thoroughly investigated. Our results indicate that the nanocarriers effectively induced X-PDT effects with very low-dose radiation, making it feasible to damage cancer cells. This suggests the potential for the effective utilization of X-PDT in treating hypoxic cancers, including TNBC, with only a fraction of conventional radiotherapy.


Fluorocarbons , Hydrocarbons, Brominated , Photochemotherapy , Protoporphyrins , Triple Negative Breast Neoplasms , Humans , Photochemotherapy/methods , Liposomes/therapeutic use , Triple Negative Breast Neoplasms/drug therapy , Reactive Oxygen Species/metabolism
7.
Sci Rep ; 14(1): 6486, 2024 03 18.
Article En | MEDLINE | ID: mdl-38499858

Brominated flame retardants (BFRs) are a group of chemicals widely used in various applications to prevent or slow down the spread of fire. However, they have adverse effects on human health. There is a relative scarcity of population-based studies regarding BFRs, particularly their impact on the respiratory system. This study aimed to investigate the influence of BFRs on pulmonary function using data from the National Health and Nutrition Examination Survey. The study found that elevated serum concentrations of certain BFRs were associated with pulmonary ventilatory dysfunction. Adjusted analyses revealed positive correlations between PBDE47, PBDE183, and PBDE209 concentrations and ventilatory dysfunction. The analysis of mixed BFRs showed a positive relationship with pulmonary ventilation dysfunction, with PBDE47 making the most significant contribution. Our study demonstrates that both individual and combined BFRs exposure can lead to impaired pulmonary ventilation function. These findings provide evidence of the adverse effects of BFRs on lung function, emphasizing the importance of further investigating the potential health consequences of these compounds. Further large-scale longitudinal studies are needed to investigate this relationship in the future.


Drug-Related Side Effects and Adverse Reactions , Flame Retardants , Hydrocarbons, Brominated , Adult , Humans , Hydrocarbons, Brominated/adverse effects , Flame Retardants/adverse effects , Flame Retardants/analysis , Cross-Sectional Studies , Nutrition Surveys , Halogenated Diphenyl Ethers/analysis , Lung/chemistry
8.
PLoS Med ; 21(3): e1004352, 2024 Mar.
Article En | MEDLINE | ID: mdl-38547322

BACKGROUND: Prolonged labor is a common condition associated with maternal and perinatal complications. The standard treatment with oxytocin for augmentation of labor increases the risk of adverse outcomes. Hyoscine butylbromide is a spasmolytic drug with few side effects shown to shorten labor when used in a general population of laboring women. However, research on its effect on preventing prolonged labor is lacking. We aimed to assess the effect of hyoscine butylbromide on the duration of labor in nulliparous women showing early signs of slow labor. METHODS AND FINDINGS: In this double-blind randomized placebo-controlled trial, we included 249 nulliparous women at term with 1 fetus in cephalic presentation and spontaneous start of labor, showing early signs of prolonged labor by crossing the alert line of the World Health Organization (WHO) partograph. The trial was conducted at Oslo University Hospital in Norway from May 2019 to December 2021. One hundred and twenty-five participants were randomized to receive 1 ml hyoscine butylbromide (Buscopan) (20 mg/ml), while 124 received 1 ml sodium chloride intravenously. Randomization was computer-generated, with allocation concealment by opaque sequentially numbered sealed envelopes. The primary outcome was duration of labor from administration of the investigational medicinal product (IMP) to vaginal delivery, which was analyzed by Weibull regression to estimate the cause-specific hazard ratio (HR) of vaginal delivery between the 2 treatment groups, with associated 95% confidence interval (CI). A wide range of secondary maternal and perinatal outcomes were also evaluated. Time-to-event outcomes were analyzed by Weibull regression, whereas continuous and dichotomous outcomes were analyzed by median regression and logistic regression, respectively. All main analyses were based on the modified intention-to-treat (ITT) set of eligible women with signed informed consent receiving either of the 2 treatments. The follow-up period lasted during the postpartum hospital stay. All personnel, participants, and researchers were blinded to the treatment allocation. Median (mean) labor duration from IMP administration to vaginal delivery was 401 (440.8) min in the hyoscine butylbromide group versus 432.5 (453.6) min in the placebo group. We found no statistically significant association between IMP and duration of labor from IMP administration to vaginal delivery: cause-specific HR of 1.00 (95% CI [0.77, 1.29]; p = 0.993). Among 255 randomized women having received 1 dose of IMP, 169 women (66.3%) reported a mild adverse event: 75.2% in the hyoscine butylbromide group and 57.1% in the placebo group (Pearson's chi-square test: p = 0.002). More than half of eligible women were not included in the study because they did not wish to participate or were not included upon admission. The participants might have represented a selected group of women reducing the external validity of the study. CONCLUSIONS: One intravenous dose of 20 mg hyoscine butylbromide was not found to be superior to placebo in preventing slow labor progress in a population of first-time mothers at risk of prolonged labor. Further research is warranted to answer whether increased and/or repeated doses of hyoscine butylbromide might have an effect on duration of labor. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03961165) EudraCT (2018-002338-19).


Butylscopolammonium Bromide , Hydrocarbons, Brominated , Labor, Obstetric , Female , Humans , Pregnancy , Butylscopolammonium Bromide/adverse effects , Double-Blind Method , Parasympatholytics/adverse effects , Scopolamine
9.
J Hazard Mater ; 469: 134036, 2024 May 05.
Article En | MEDLINE | ID: mdl-38493623

1,2,5,6,9,10-Hexabromocyclododecanes (HBCDs) are a sort of persistent organic pollutants (POPs). This research investigated 12 microbial communities enriched from sediments of four mangroves in China to transform HBCDs. Six microbial communities gained high transformation rates (27.5-97.7%) after 12 generations of serial transfer. Bacteria were the main contributors to transform HBCDs rather than fungi. Analyses on the bacterial compositions and binning genomes showed that Alcanivorax (55.246-84.942%) harboring haloalkane dehalogenase genes dadAH and dadBH dominated the microbial communities with high transformation rates. Moreover, expressions of dadAH and dadBH in the microbial communities and Alcanivorax isolate could be induced by HBCDs. Further, it was found that purified proteins DadAH and DadBH showed high conversion rates on HBCDs in 36 h (91.9 ± 7.4 and 101.0 ± 1.8%, respectively). The engineered Escherichia coli BL21 strains harbored two genes could convert 5.7 ± 0.4 and 35.1 ± 0.1% HBCDs, respectively, lower than their cell-free crude extracts (61.2 ± 5.2 and 56.5 ± 8.7%, respectively). The diastereoisomer-specific transforming trend by both microbial communities and enzymes were γ- > α- > ß-HBCD, differed from α- > ß- > Î³-HBCD by the Alcanivorax isolate. The identified transformation products indicated that HBCDs were dehalogenated via HBr elimination (dehydrobromination), hydrolytic and reductive debromination pathways in the enriched cultures. Two enzymes converted HBCDs via hydrolytic debromination. The present research provided theoretical bases for the biotransformation of HBCDs by microbial community and the bioremediation of HBCDs contamination in the environment.


Flame Retardants , Hydrocarbons, Brominated , Microbiota , Stereoisomerism , Hydrocarbons, Brominated/metabolism , Biotransformation , Bacteria/metabolism
10.
Toxicol Lett ; 394: 11-22, 2024 Apr.
Article En | MEDLINE | ID: mdl-38387762

BACKGROUND: The incidence of endocrine-related cancer, which includes tumors in major endocrine glands such as the breast, thyroid, pituitary, and prostate, has been increasing year by year. Various studies have indicated that brominated flame retardants (BFRs) are neurotoxic, endocrine-toxic, reproductive-toxic, and even carcinogenic. However, the epidemiological relationship between BFR exposure and endocrine-related cancer risk remains unclear. METHODS: We searched the PubMed, Google Scholar, and Web of Science databases for articles evaluating the association between BFR exposure and endocrine-related cancer risk. The odds ratio (OR) and its corresponding 95% confidence interval (95% CI) were used to assess the association. Statistical heterogeneity among studies was assessed with the Q-test and I2 statistics. Begg's test was performed to evaluate the publication bias. RESULTS: We collected 15 studies, including 6 nested case-control and 9 case-control studies, with 3468 cases and 4187 controls. These studies assessed the risk of breast cancer, thyroid cancer, and endocrine-related cancers in relation to BFR levels. Our findings indicate a significant association between BFR exposure in adipose tissue and an increased risk of breast cancer. However, this association was not observed for thyroid cancer. Generally, BFR exposure appears to elevate the risk of endocrine-related cancers, with a notable increase in risk linked to higher levels of BDE-28, a specific polybrominated diphenyl ether congener. CONCLUSIONS: In conclusion, although this meta-analysis has several limitations, our results suggest that BFR exposure is a significant risk factor for breast cancer, and low-brominated BDE-28 exposure could significantly increase the risk of endocrine-related cancers. Further research is essential to clarify the potential causal relationships between BFRs and endocrine-related cancers, and their carcinogenic mechanisms.


Breast Neoplasms , Flame Retardants , Hydrocarbons, Brominated , Polybrominated Biphenyls , Male , Humans , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Risk Factors , Hydrocarbons, Brominated/toxicity
11.
Environ Pollut ; 346: 123645, 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38402939

Brominated flame retardants (BFRs) are bromine-bearing additives added to the polymeric fraction in various applications to impede fire ignition. The Stockholm Convention and various other legislations abolished legacy BFRs usage and hence, the so-called novel BFRs (NBFRs) were introduced into the market. Recent studies spotlighted their existence in household dust, aquifers and aquatic/aerial species. Co-pyrolysis of BFRs with metal oxides has emerged as a potent chemical recycling approach that produces a bromine-free stream of hydrocarbon. Herein, we investigate the debromination of two prominent two NBFRs; namely tetrabromobisphenol A 2,3-dibromopropyl ether (TD) and tetrabromobisphenol A diallyl ether (TAE) through their co-pyrolysis with zinc oxide (ZnO) and franklinite (ZnFe2O4). Most of the zinc content in electrical arc furnace dust (EAFD) exists in the form of these two metal oxides. Conversion of these metal oxides into their respective bromides could also assist in the selective extraction of the valuable zinc content in EAFD. The debromination potential of both oxides was unveiled via a multitude of characterization studies to analyze products (char, gas and condensates). The thermogravimetric analysis suggested a pyrolytic run up to 500 °C and the TAE treatment with ZnO produced only a trivial amount of brominated compounds (relative area, 0.83%). Phenol was the sole common compound in condensable products; potentially formed by the ß-scission debromination reaction from the parental molecular skeleton. Inorganic compounds and methane were the major constituents in the gaseous products. The pyrochar analyses confirmed the presence of metal bromides retained in the residue, averting the bromine release into the atmosphere. The ion chromatography analysis portrayed <8% of HBr gas release into the atmosphere upon pyrolysis with ZnO. The ZnO dominance herein envisaged further probes into other spinel ferrites in combating brominated polymers.


Electronic Waste , Flame Retardants , Hydrocarbons, Brominated , Polybrominated Biphenyls , Zinc Oxide , Flame Retardants/analysis , Electronic Waste/analysis , Bromine , Bromides , Recycling/methods , Polymers , Zinc/analysis , Dust , Ethers , Hydrocarbons, Brominated/analysis
12.
Aquat Toxicol ; 268: 106853, 2024 Mar.
Article En | MEDLINE | ID: mdl-38330652

Hexabromocyclododecane (HBCD), third-generation brominated flame retardants (BRFs), has aroused worldwide concern because of its wide application and potentially negative impacts on marine ecosystems, but an information gap still exists regarding marine low-trophic organisms. Brachionus plicatilis, the model marine zooplankton, was used in the present study, and its reproductive responses were used as the endpoint to indicate HBCD-induced toxicity. HBCD was suggested to be extremely highly toxic compounds regarding the 96 h-LC50 of 0.58 mg L-1. The sublethal exposure of HBCD injured the reproduction of B. plicatilis: The total number of offspring per female and the key population index calculated from the life table, including the intrinsic rate of population increase (rm) and net reproductive rate (R0), were significantly influenced in a concentration-dependent manner. The reproductive process was also altered, as indicated by the first spawning time, first hatching time and oocyst development time. At the same time, individual survival and growth (body length) were also negatively affected by HBCD. Reactive oxygen species (ROS) were suggested to be responsible for reproductive toxicity mainly because the total ROS contents as well as the main components of •OH and H2O2 greatly increased and resulted in the oxidative imbalance that presented as malondialdehyde (MDA) elevation. Simultaneous activation of the glutathione antioxidant system was accompanied by the apoptosis marker enzymes Caspase-3 and 9, as well as the correlation between ROS content, physiological alteration and cell apoptosis, providing further evidence for this. The integrated biomarker response (IBR) and adverse outcome pathway (AOP) showed that HBCD had a significant toxic effect on B. plicatilis near the concentration range of 96 h-LC50. The establishment of this concentration range will provide a reliable reference for future environmental concentration warning of HBCD in marine.


Flame Retardants , Hydrocarbons, Brominated , Rotifera , Water Pollutants, Chemical , Animals , Female , Reactive Oxygen Species/metabolism , Ecosystem , Hydrogen Peroxide , Water Pollutants, Chemical/toxicity , Hydrocarbons, Brominated/toxicity , Reproduction , Flame Retardants/toxicity
13.
Environ Sci Technol ; 58(9): 4127-4136, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-38382014

Tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) has come into use as an alternative to hexabromocyclododecane (HBCD), but it is unclear whether TBBPA-DBMPE has less hazard than HBCD. Here, we compared the bioaccumulation and male reproductive toxicity between TBBPA-DBMPE and HBCD in mice following long-term oral exposure after birth. We found that the concentrations of TBBPA-DBMPE in livers significantly increased with time, exhibiting a bioaccumulation potency not substantially different from HBCD. Lactational exposure to 1000 µg/kg/d TBBPA-DBMPE as well as 50 µg/kg/d HBCD inhibited testis development in suckling pups, and extended exposure up to adulthood resulted in significant molecular and cellular alterations in testes, with slighter effects of 50 µg/kg/d TBBPA-DBMPE. When exposure was extended to 8 month age, severe reproductive impairments including reduced sperm count, increased abnormal sperm, and subfertility occurred in all treated animals, although 50 µg/kg/d TBBPA-DBMPE exerted lower effects than 50 µg/kg/d HBCD. Altogether, all data led us to conclude that TBBPA-DBMPE exerted weaker male reproductive toxicity than HBCD at the same doses but exhibited bioaccumulation potential roughly equivalent to HBCD. Our study fills the data gap regarding the bioaccumulation and toxicity of TBBPA-DBMPE and raises concerns about its use as an alternative to HBCD.


Flame Retardants , Hydrocarbons, Brominated , Polybrominated Biphenyls , Male , Animals , Mice , Flame Retardants/toxicity , Ether , Bioaccumulation , Semen , Hydrocarbons, Brominated/toxicity , Polybrominated Biphenyls/toxicity , Ethers , Ethyl Ethers
14.
Environ Sci Technol ; 58(9): 4237-4246, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-38386008

Concentrations of polybrominated diphenyl ethers, hexabromocyclododecane (HBCDD), and novel brominated flame retardants (NBFRs) were measured in indoor dust, indoor air, and outdoor air in Birmingham, UK. Concentrations of ΣBFRs ranged from 490 to 89,000 ng/g, 46-14,000 pg/m3, and 22-11,000 pg/m3, respectively, in UK indoor dust, indoor air, and outdoor air. BDE-209 and decabromodiphenyl ethane (DBDPE) were the main contributors. The maximum concentration of DBDPE (10,000 pg/m3) in outdoor air is the highest reported anywhere to date. In contrast with previous studies of outdoor air in Birmingham, we observed significant correlations between concentrations of tri- to hepta-BDEs and HBCDD and temperature. This may suggest that primary emissions from ongoing use of these BFRs have diminished and that secondary emissions (e.g., evaporation from soil) are now a potentially major source of these BFRs in outdoor air. Conversely, the lack of significant correlations between temperature and concentrations of BDE-209 and DBDPE may indicate that ongoing primary emissions from indoor sources remain important for these BFRs. Further research to clarify the relative importance of primary and secondary sources of BFRs to outdoor air is required. Comparison with earlier studies in Birmingham reveals significant (p < 0.05) declines in concentrations of legacy BFRs, but significant increases for NBFRs over the past decade. While there appear minimal health burdens from BFR exposure for UK adults, dust ingestion of BDE-209 may pose a significant risk for UK toddlers.


Air Pollution, Indoor , Flame Retardants , Hydrocarbons, Brominated , Adult , Humans , Air Pollution, Indoor/analysis , Dust/analysis , Environmental Monitoring , Flame Retardants/analysis , Halogenated Diphenyl Ethers/analysis , United Kingdom , Bromine/analysis
15.
Int J Mol Sci ; 25(2)2024 Jan 10.
Article En | MEDLINE | ID: mdl-38255957

In this work, we present the effect of graphene nanoplatelets (GnPs) modification with ionic liquids (ILs). The textural properties of graphene nanoplatelets (GnPs) used as styrene-butadiene rubber's filler and the thermal properties of the composites obtained with the use of the mentioned fillers were investigated. GnPs were modified with 1-butylpyridinium bromide (BPyBr) and 4-methyl-1-butylpyridinium bromide (BmPyBr) through two different ways. One strategy has been to deposit the filler modifier from the solution. The second one involved the modification of the filler with ionic liquids in bulk during the preparation of elastomer blends. Settlement of the proposed ionic liquids onto the GnPs' surface led to significant changes in the textural characteristics. BPyBr has restricted the filler's microporosity, whereas BmPyBr has caused the formation of a more opened filler structure without the increase in its average pore size. GnPs modified with ILs led to reducing the temperature of vulcanization of SBR compounds and affected the thermal stability of the composites.


Graphite , Hydrocarbons, Brominated , Ionic Liquids , Bromides , Elastomers , Excipients
16.
Braz Oral Res ; 38: e001, 2024.
Article En | MEDLINE | ID: mdl-38198301

The aim of this study was to evaluate the influence of adding quaternary ammonium methacrylates (QAMs) to experimental adhesives by assessing the degree of conversion (DC), cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. Two QAMs were added to an experimental adhesive: dimethylaminododecyl methacrylate bromododecane (DMADDM) or dimethylaminododecyl methacrylate bromohexadecane (DMAHDM) at three concentrations each: 1, 2.5, and 5 wt.%. Experimental adhesive without QAMs (control group) and commercially available Transbond XT Primer (3M Unitek, Monrovia, California, USA) were used for comparisons. The adhesives were tested for DC, cytotoxicity against keratinocytes and fibroblasts, and antibacterial activity against biofilm formation. DC, cytotoxicity against fibroblasts, and antibacterial activity were analyzed using one-way ANOVA and Tukey's multiple comparisons. Cytotoxicity against keratinocytes was evaluated using the Kruskal Wallis and Dunn's post-hoc (α = 5%) tests. Transbond showed lower DC as compared to 5% DMAHDM, 1% DMADDM, and 5% DMADDM (p < 0.05). However, all groups presented proper DC when compared to commercial adhesives in the literature. In the evaluation of cytotoxicity against keratinocytes, Transbond induced higher viability than 2.5 wt.% groups (p < 0.05). Against fibroblasts, Transbond induced higher viability as compared to 5 wt.% groups (p < 0.05). DMAHDM at 5 wt.% reduced biofilm formation when compared to all the other groups (p < 0.05). Despite their cytotoxic effect against keratinocytes, gingival fibroblasts showed higher viability. DMAHDM at 5 wt.% decreased Streptococcus mutans viability. The incorporation of DMAHDM at 5 wt.% may be a strategy for reducing the development of white spot lesions.


Anti-Bacterial Agents , Bisphenol A-Glycidyl Methacrylate , Hydrocarbons, Brominated , Methacrylates , Methylamines , Quaternary Ammonium Compounds , Methacrylates/pharmacology , Anti-Bacterial Agents/pharmacology
17.
Mar Environ Res ; 194: 106314, 2024 Feb.
Article En | MEDLINE | ID: mdl-38185000

Pollutants in the ecological environment of fishery seawater are harmful to the survival and reproduction of aquatic organisms. Hexabromocyclododecanes (HBCDs) were 42.9% detected within ND-48.89 ng/L in 177 seawater samples and 30.7% within ND-1.07 ng/g dw in 88 sediment samples of the fisheries in the Yellow Sea and East China Sea, respectively. γ-HBCD accounted for 65% of seawater and 89% of sediment samples. HBCDs in seawater in winter (ND-48.89 ng/L) were significantly higher than in summer (ND-4.99 ng/L), possibly because the re-suspension caused by winds and waves could re-migrate HBCDs from the sediment to the seawater in winter. However, seasonal differences of HBCDs in sediment were not significant. The fugacities indicated HBCDs' migrating trend from seawater to sediment due to their hydrophobic nature. There is almost no terrestrial input of HBCDs from the Yangtze and Yellow Rivers, and currently used fishery materials in marine may compose long-lasting sources of HBCDs.


Environmental Monitoring , Hydrocarbons, Brominated , Water Pollutants, Chemical , Seasons , Geologic Sediments/chemistry , Water Pollutants, Chemical/analysis , Hunting , Seawater , China
18.
Environ Int ; 183: 108409, 2024 Jan.
Article En | MEDLINE | ID: mdl-38185044

Persistent pollutants, namely brominated flame retardants (BFRs) and heavy metals, are compounds that are added to a wide range of products and materials for preventing ignition, increasing the functionality of materials or improving their performance, e.g. electric conductivity. The exposure of children might consequently be inferred, through indoor dust and hand-to-mouth or toy-chewing behaviors. The current study is aimed at assessing the exposure of Moroccan children to BFRs and heavy metal elements, and evaluating their associations with global DNA methylation. First, parents responded to a questionnaire pertaining to children's lifestyle, then blood and urine samples were collected from (n = 93) children aged between 5 and 11 years for biomonitoring and DNA methylation analysis. BFRs were detected in 54.84% of samples with a median concentration of 0.01 nmol/mL (range: 0.004-0.051 nmol/mL) while metal elements were detected in more than 90% of samples. BFRs showed no variations with global DNA methylation, unlike metal elements, which revealed significant associations with global DNA methylation markers, namely 5-mC, 5-hmC and N6-mA levels. Moroccan children may be exposed to flame retardants and heavy metals through several routes. Further research is required to assess the exposure and the health impacts of environmental pollutants and ultimately protect the Moroccan population by the prevention of adverse health effects.


Air Pollution, Indoor , Environmental Pollutants , Flame Retardants , Hydrocarbons, Brominated , Metals, Heavy , Child , Humans , Child, Preschool , Flame Retardants/analysis , Morocco , Air Pollution, Indoor/analysis , Halogenated Diphenyl Ethers/analysis , Environmental Pollutants/analysis , Dust/analysis , Metals, Heavy/analysis , Adenine/analysis , Environmental Monitoring , Environmental Exposure/analysis , Hydrocarbons, Brominated/analysis
19.
J Mater Chem B ; 12(4): 991-1000, 2024 Jan 24.
Article En | MEDLINE | ID: mdl-38193597

Hair dermal papilla cells (hDPCs) play a crucial role in hair growth and regeneration, and their function is influenced by nutrient and oxygen supply. A microenvironment with significantly low oxygen (O2) levels, known as anoxic conditions (<0.2%) due to oxygen deficiency, hinders hDPC promotion and retards hair regrowth. Here, a nanoemulsion (NE) based on perfluorooctyl bromide (PFOB), a member of the perfluorocarbon family, is presented to provide a sustainable O2 supply and maintain physical stability in vitro. The PFOB-NE has been shown to continuously release oxygen for 36 h, increasing and maintaining the O2 concentration in the anoxic microenvironment of up to 0.8%. This sustainable O2 supply using PFOB-NE has promoted hDPC growth and also induced a complex cascade of effects. These effects encompass regulation via inhibiting lactate accumulation caused via oxygen deficiency, increasing lactate dehydrogenase activity, and promoting the expression of genes, such as the hypoxia-inducible factor 1 family and NADPH oxidase 4 under anoxic conditions. Sustained O2 supply is shown to enhance human hair organ elongation approximately four times compared to the control under anoxic conditions. In conclusion, the perfluorocarbon-based NE containing oxygen proves to be an important strategic tool for improving hair growth and alleviating hair loss.


Fluorocarbons , Hydrocarbons, Brominated , Hypoxia , Humans , Oxygen/metabolism , Fluorocarbons/pharmacology , Hair
20.
J Environ Qual ; 53(1): 47-56, 2024.
Article En | MEDLINE | ID: mdl-37939688

Methyl bromide (MeBr) is a sterilizing fumigant used to control quarantine pests that is restricted due to its detrimental atmospheric effects. The degradation of injected MeBr produces crop-available Br- . Up to five applications of MeBr were used in southeastern Idaho fields to combat the pale cyst nematode (Globodera pallida). Data regarding the uptake and partitioning of Br- in crops following MeBr application in the region were unavailable. Research determined background concentrations of Br- in alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), corn (Zea mays L.), potato (Solanum tuberosum L.), and wheat (Triticum aestivum L.) compared to MeBr-treated fields. Background Br- concentrations ranged from nondetectable (ND) to 33.0 mg Br- kg-1 ; vegetative tissue concentrations were greater than reproductive, except corn where there was no difference. Nearly all crops grown in MeBr-treated fields had greater Br- concentrations than background. Background-baled-alfalfa tissue Br- concentration was 33.0 mg kg-1 compared to 117.8 mg Br- kg-1 from a MeBr-treated field. Br- concentration in green alfalfa decreased from 79.8 to 36.5 mg Br- kg-1 at the final cutting in a MeBr-treated field, where time after application decreased crop Br- concentrations. Small grains had low Br- concentrations in reproductive tissue (1.7 mg Br- kg-1 ) compared to vegetative tissue (106.5 mg Br- kg-1 ). Corn stover concentration (12.7 mg Br- kg-1 ) was low relative to small-grain straw, but corn ear (5.8 mg Br- kg-1 ) was greater than small-grain reproductive tissue in the MeBr-treated field. Crop selection following MeBr applications should consider the likelihood of elevated Br- concentration for the plant fractions intended end use.


Bromides , Hydrocarbons, Brominated , Nematoda , Animals , Fumigation , Idaho
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