Tetrabromobisphenol A Research Articles

Postnatal exposure to low-dose tetrabromobisphenol A increases the susceptibility of mammal testes to chemical-induced spermatogenic stress in adulthood

There is increasing data showing that some environmental chemicals can increase susceptibility to follow-up stress or injuries, possibly thereby contributing to certain clinical and subclinical diseases. Previous studies reported that tetrabromobisphenol A (TBBPA), one of the most used brominated flame retardants, exerted little male reproductive toxicity in terms of conventional endpoints but affected testis development and thereby caused testicular alterations at the molecular and cellular levels. Here, we aimed to reveal whether developmental exposure to TBBPA can increase testicular susceptibility to follow-up stress in adulthood. For this purpose, newborn mice were exposed to 50 or 500 μg/kg/d TBBPA for 56 days to confirm adverse effects on testes, followed by a single intraperitoneal injection of 3 mg/kg busulfan (BSF) to induce spermatogenic stress. Four weeks after BSF injection, TBBPA-treated mice exhibited severe pathological alterations, including reduced testis weight, damaged testicular histological structure, declined sperm count, apoptosis of spermatogenic cells, while no remarkable damage was observed in mice without historical exposure to TBBPA. These results demonstrate that historical exposure to TBBPA, either 50 or 500 µg/kg/d, increased the susceptibility of mouse testes to BSF-induced spermatogenic stress, resulting in severe adverse reproductive outcomes. Further analysis indicates that TBBPA-caused microtubule and microfilament damage, along with spermatogonia and spermatocyte reduction, could contributed to the increased susceptibility of testes, suggesting that these non-conventional reproductive lesions caused by chemicals should not be ignored. This is the first study to investigate the reproductive hazard of chemicals from the perspective of testicular susceptibility to stress, thereby opening a new avenue to identify environmental chemicals possibly contributing to male infertility and subfertility.

Enhanced reductive degradation of tetrabromobisphenol A by biochar supported sulfidated nanoscale zero-valent iron: Selectivity and core reactivity

A core-shell structure of sulfidated nanoscale zero-valent iron deposited on biochar (S-nZVI/BC) was synthesized and the performance of S-nZVI/BC on tetrabromobisphenol A (TBBPA) degradation was investigated. Detailed characterizations indicated that controlling S content altered distribution of S species (i.e., S2-, S22-, and Sn2-) in shell and core and achieved higher hydrophobicity and lower electron-transfer resistance. S-nZVI/BC was highly reactive (∼4.3–11.3 times) and selective (∼78.9–152.6 times) over nZVI/BC for TBBPA degradation. Besides, BC improved reactivity and selectivity of S-nZVI by 0.17 and 1.35 times, respectively, deriving from increased electron-transfer, enhanced hydrophobicity, and more surface reduced S species. Thus, sulfidation and BC enhanced reactivity and selectivity of S-nZVI/BC by combining respective merits. Effects of initial TBBPA concentration, pH, and particles dosage on TBBPA degradation by S-nZVI/BC were also investigated. Remarkably, mechanism investigation revealed that core properties instead of shell dominated reactivity and TBBPA debromination mainly involved direct electron-transfer rather than atomic H.

Time- and dose-dependent detoxification and reproductive endocrine disruption induced by tetrabromobisphenol A (TBBPA) in mussel Mytilus galloprovincialis

As a typical brominated flame retardant (BFR), tetrabromobisphenol A (TBBPA) has been frequently detected in both biotic and abiotic matrices in marine environment. Our previous study found that genes related to metabolism phase I/II/III as well as steroid metabolism in Mytilus galloprovincialis were significantly altered by TBBPA treatment. However, the time- and dose-dependent response profiles of these genes to TBBPA exposure were rarely reported. In this study, the time- and dose-dependent effects of TBBPA on detoxification and reproductive endocrine disruption in M. galloprovincialis were explored by evaluating the responses of related gene expressions, enzymatic activities and gametogenesis to different concentrations of TBBPA (0.6, 3, 15, 75 and 375 μg/L) for different durations (14, 21 and 28 days). The results showed that the TBBPA accumulation increased linearly with the increases of exposure time and dose. Cytochrome P450 family 3 (CYP3A1-like) cooperated with CYP4Y1 for phase I biotransformation of TBBPA in mussels. The dose-response curves of phase II/III genes (glutathione-S-transferase (GST), P-glycoprotein (ABCB), and multidrug resistance protein (ABCC)) showed similar response profiles to TBBPA exposure. The common induction of phase I/II/III (CYPs, GST, ABCB and ABCC) suggested TBBPA detoxification regulation in mussels probably occurred in a step-wise manner. Concurrently, direct sulfation mediated by sulfotransferases (SULTs) on TBBPA was also the vital metabolic mechanism for TBBPA detoxification, which was supported by the coincidence between up-regulation of SULT1B1 and TBBPA accumulation. The significant promotion of steroid sulfatase (STS) might result from TBBPA-sulfate catalyzed by SULT1B1 due to its chemical similarity to estrone-sulfate. Furthermore, the promotion of gametogenesis was consistent with the induction of STS, suggesting that STS might interrupt steroids hydrolysis process and was responsible for reproductive endocrine disruption in M. galloprovincialis. This study provides a better understanding of the detoxification and endocrine-disrupting mechanisms of TBBPA.

Synthesis and Characterization of BaTiO3/TiO2 Heterojunction Photocatalyst for Novel Application in Photocatalytic Degradation of TBBPA under Simulated Sunlight Irradiation

AbstractThe polyacrylamide gel method combined with low temperature sintering technology (PGMCLTST) have been used to synthesize the BaTiO3/TiO2 heterojunction photocatalysts. The BaTiO3/TiO2 heterojunction photocatalyst only contains tetragonal BaTiO3, rutile TiO2 and anatase TiO2, without any other impurities. Based on a variety of characterization, it was confirmed that a special heterojunction was formed between BaTiO3 and TiO2, and there were a large number of interface defects or oxygen defects in the samples. The BaTiO3/10 wt % TiO2 heterojunction photocatalysts have high photocatalytic activity for the degradation of tetrabromobisphenol A (TBBPA) under simulated sunlight irradiation. The interfacial defects enhance the transfer and separation efficiency of charge carriers in BaTiO3/TiO2 heterojunction photocatalysts. This technique provides a new idea for the application of BaTiO3/TiO2 heterojunction photocatalysts and other heterojunction photocatalysts in the degradation of persistent organic pollutants (POPs).

TBBPA induces inflammation, apoptosis, and necrosis of skeletal muscle in mice through the ROS/Nrf2/TNF-α signaling pathway

Tetrabromobisphenol A (TBBPA) is present in large quantities in the environment due to its widespread use. And TBBPA is capable of accumulating in animals, entering the ecological chain and causing widespread damage to organisms. TBBPA is capable of causing the onset of oxidative stress, which induces tissue damage and cell death, which in turn affects the physiological function of tissues. Skeletal muscle is a critical tissue for maintaining growth, movement, and health in the body. However, the mechanism of TBBPA-induced skeletal muscle injury remains unclear. In this study, we constructed mouse skeletal muscle models (10, 20, and 40 mg/kg TBBPA) and mouse myoblasts (C2C12) cell models (2,4, and 8 μg/L TBBPA) at different concentrations. The results of this experiment showed that under TBBPA treatment, the levels of reactive oxygen species (ROS) and Malondialdehyde (MDA) in mouse skeletal and C2C12 cells were increased significantly, but the activities of some antioxidant enzymes decreased. TBBPA can inhibit Nuclear factor E2-related factor 2 (Nrf2) entry into the nucleus, thus affecting the expression of the Nrf2 downstream factors. With the increase of TBBPA concentration, the expression levels of inflammatory factors were significantly increased, while the anti-apoptotic factors were significantly decreased. The expression of pro-apoptotic factors increased in a dose-dependent manner. Programmed necrosis-related factors were also significantly elevated. Our results suggest that TBBPA induces oxidative stress and inflammation, apoptosis, and necrosis in the skeletal muscle of mice by regulating Nrf2/ROS/TNF-α signaling pathway.

Breast adipose metabolites mediates the association of tetrabromobisphenol a with breast cancer: A case-control study in Chinese population

Studies exploring the association of tetrabromobisphenol A (TBBPA) with breast cancer and related mechanisms are limited. To investigate the relationship between TBBPA levels in breast adipose and breast cancer, we carried out case-control research. As well as further examine the mediating role of adipose metabolites between TBBPA and breast cancer using the metabolomics approach. In this study, the concentration of TBBPA was determined utilizing ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) after a solid phase extraction (SPE) pretreatment. High-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was employed to analyze adipose metabolomics. Evaluation of metabolites linked to TBBPA exposure and breast cancer was performed utilizing mediation analysis. With an estimated OR (95%CI) of 1.153 (1.023, 1.299), TBBPA was firmly linked with breast cancer. We also used propensity score matching analysis and sensitivity analysis to reduce the effect of confounding factors on the results. Metabolomics of adipose suggested significant perturbation in the linoleic acid metabolism pathway. In addition, for PC (16:0/16:0) as phospholipids, a mediation effect on the associations of TBBPA exposure with breast cancer risks was observed (estimated mediation percentage: 56.58%). Understanding the relationship between TBBPA exposure and the risk of breast cancer may be facilitated by the findings, which point to potential mediation metabolites.

Persulfate activation with sodium alginate/sulfide coated iron nanoparticles for degradation of tetrabromobisphenol a in soil

The accumulation of tetrabromobisphenol A (TBBPA) in soil posed a serious threat to ecosystem and human health. Sodium alginate/sulfide coated iron nanoparticles (SA@S–Fe NPs) was synthesized by a two-step modification of Fe NPs prepared with tung tree leaves extracting solution, and utilized as a persulfate (PS) activator to degrade TBBPA in soil. Response surface methodology (RSM) optimization showed a theoretical maximum TBBPA degradation reaching 99.79% at the 34.28 °C, SA@S–Fe NPs and PS additions of 3.57 g kg−1 and 36.35 mM, respectively. The degradation mechanism of TBBPA suggested that the main reactive species produced in the SA@S–Fe NPs/PS system were •OH, SO4•−, and O2•−. Proposed mechanisms for the degradation of TBBPA in soil involved debromination, benzene rings split, hydroxylation, demethylation, and complete mineralization to CO2 and H2O. We also further studied the effect to soil physicochemical properties and morphology structure during TBBPA degradation in SA@S–Fe NPs/PS system, which showed that SOM, TN, C/N and TOC slightly reduced, the heavy metals Fe, Cu and Zn still existed in stable residue form, and the soil morphology showed a certain degree of aggregation. Therefore SA@S–Fe NPs/PS technology can effectively degrade soil TBBPA, maintain soil fertility, curb the migration of heavy metals, and environmental risks.

Adverse effects of thyroid-hormone-disrupting chemicals 6-propyl-2-thiouracil and tetrabromobisphenol A on Japanese medaka (Oryzias latipes)

Thyroid-hormone-disrupting chemicals are increasingly attracting attention because of their potential harmful effects on animal health, including on fishes. Here, we investigated the effects of exposure to the thyroid-hormone-disrupting chemicals 6-propyl-2-thiouracil (PTU) and tetrabromobisphenol A (TBBPA) on swim bladder inflation, eye development, growth, swimming performance, and the expression of thyroid-related genes in Japanese medaka (Oryzias latipes). PTU exposure resulted in reductions in eye size, growth, and swim bladder inflation, and these effects led to poorer swimming performance. These phenotypic effects were accompanied by increased expression of the thyroid-stimulating hormone subunit beta (tshβ) paralog tshβ-like, but there were no significant changes in expression for tshβ, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trβ). For PTU exposure, we identified the key event (swim bladder inflation reduction) and an adverse outcome (swimming performance reduction). No significant effects from TBBPA exposure were seen on swim bladder inflation, eye development, growth, or swimming performance. However, expression of tshβ-like and tshβ (significantly enhanced) and trα and trβ (significantly reduced) were affected by TBBPA exposure albeit not in dose-dependent manners. There were no effects of TBBPA on the expression of dio1 and dio2. We thus show that the two thyroid-hormone-disrupting chemicals PTU and TBBPA differ in their effect profiles with comparable effects on the studied phenotypes and thyroid-related gene expression to those reported in zebrafish.

Performance and mechanisms for tetrabromobisphenol A efficient degradation in a novel homogeneous advanced treatment based on S2O42− activated by Fe3+

Tetrabromobisphenol A (TBBPA), a representative brominated flame retardant (BFR), generally could be debrominated and degraded effectively in photolysis systems with the high energy consumption. In this study, the novel sulfate radical (SO4•-) generation resource of dithionite (S2O42−), activated by the common transition metal of Fe3+, has been applied for establishing an innovative homogeneous advance treatment system for BFR treatment in water. When coupling Fe3+ with S2O42−, TBBPA degradation efficiency could be remarkably improved from 38.7% to 93.8% with the debromination and mineralization efficiency of 83.9% and 18.5% in 60 min, respectively. The primary reactive species also have been identified as SO3•-, SO4•- and •OH responsible for TBBPA treatment and the contributions of SO4•- and •OH have been calculated as 43.8% and 28.4% for TBBPA degradation, respectively. In Fe3+/S2O42− system, TBBPA was effectively degraded in a wide initial pH range (3.0–9.0), whose activation energy was calculated as 32.01 kJ mol−1. Due to the only operation of reagents dosing, the energy consumption and cost could be decreasing significantly without any light energy input and reaction conditions (e.g., pH and dissolved oxygen) adjustment compared with the general photolysis process. Moreover, some possible degradation approaches of TBBPA also have been proposed via GC–MS including debromination, hydroxylation, methylation, and mineralization in Fe3+/S2O42− system. And these probable degradation pathways also have been confirmed with the decreased Gibbs free energy (ΔG) based on density functional theory (DFT). This study has revealed that it was promising of Fe3+/S2O42− system for BFRs degradation and detoxification efficiently through the simple operation and mild condtions.

Pristina longiseta reproduction test: chronic exposure to environmental contaminants.

Aquatic worms are considered a suitable group to evaluate the effects of contaminants on the environment, although one of the main challenges is to use the species of local occurrence. Recently, Pristina longiseta was suggested to be used in acute bioassays. In this context, this study aimed to establish a chronic exposure for ecotoxicological bioassays using the cosmopolitan species of occurrence in Brazilian freshwater P. longiseta. Firstly, we tested three exposure times (4, 7, and 10days) under the presence or absence of aeration for reproduction outputs. After determining the best configuration (7days without aeration), we assessed the effects of the chronic exposures using the standardized reference substance potassium chloride (KCl), the antibiotic sulfamethoxazole (SMX), the flame retardant tetrabromobisphenol A (TBBPA), and the sugarcane vinasse. Our results showed suitability for applying the chronic exposure using P. longiseta and indicated the sensitivity of the offspring to KCl (EC50-7d = 0.51g/L). Sulfamethoxazole and TBBPA caused a significant decrease in the offspring of P. longiseta (EC50-7d = 59.9µg/L and < 62.5µg/L, respectively). Sugarcane vinasse showed high toxicity for the species, and 4.26% of vinasse was calculated as EC50-7d. Therefore, the described protocol was successfully applied as an ecotoxicological bioassay to evaluate the effects of environmental contaminants on the reproduction rate of the freshwater worm P. longiseta.

Dual-modal immunosensor with amine functionalized CoCu-embedded mesoporous ceria oxide nanoparticle with abundant oxygen vacancies for ultrasensitive detection of tetrabromobisphenol A

A novel electrochemical (EC) sensing matrix was established for a sensitive immunoassay of tetrabromobisphenol A (TBBPA) by combining a competitive immunoreaction and dual signal output. In this study, a rod-like MnO 2 decorated reduced graphene oxide (rGO) supported Au hybrid (MnO 2 -rGO-Au) was utilized as a sensing platform to immobilize TBBPA antigens and thus label TBBPA antibodies, which were then combined with a CoCu-embedded mesoporous CeO 2 (CoCu-mCeO 2 ) catalytic probe with abundant oxygen. Remarkably, Co and Cu on the mesoporous CeO 2 (mCeO 2 ) exposed massive active sites that produced additional oxygen vacancies to ameliorate the electrocatalytic activity and redox performance of the mCeO 2 nanoparticle. Besides, CoCu-mCeO 2 acted as the secondary antibody conjugation label based on an amine functionalized bridge between mCeO 2 and the antibody and also improved the electrochemical performance. Under the optimized conditions, the fabricated immunosensor displayed: (i) a wide linear range for TBBPA detection, ranging from 0–243 ng/mL; (ii) lower detection limits of 0.034 ng/mL (according to the amperometric i - t method) and 0.076 ng/mL (calculated by differential pulse voltammetry method), respectively, which was lower than the enzyme-linked immunosorbent assay (ELISA) with a limit of detection (LOD) of 0.59 ng/mL; (iii) satisfactory accuracy and reliability (recoveries, 95%–126.2%; cyclic voltammetry (CV), 3.36%–8.9% measured by amperometric i - t method and recoveries, 95.4%–126%; CV, 3.49%–9.62% using DPV method). The designed immunosensor exhibited good sensitivity, accuracy, and excellent potential for trace TBBPA determination from various samples.

Skillfully grafted C O functional group to enhance the adsorption/photocatalytic mechanism of YMnO3/MgAl2O4 heterojunction photocatalysts

The YMnO3 with different manganese salts includes MnSO4·H2O, MnCO3 and C4H6MnO4·4H2O and YMnO3/MgAl2O4 heterojunction photocatalysts (YMO/MAO) with different mass percentage of MgAl2O4 were synthesized by a simple wet chemistry method combined with low temperature sintering technology. The effects of manganese salts on the structure, functional groups, morphology, charge states and optical properties of YMnO3 phase were studied in detail. The pure YMnO3 with the uniformity of particles can be obtained when only C4H6MnO4·4H2O is used as manganese source. The results confirmed that the YMO/MAO heterojunction was constructed by one step low-temperature sintering technique. The YMnO3/wt 10 % MgAl2O4 photocatalyst exhibits high optical absorption coefficient and highest adsorption capacity of 122.86 mg/g and degradation percentage of 98.98 % for the degradation of Congo red (CR), 86.16 % for the degradation of tetracycline hydrochloride (TC) and 72.51 % for the degradation of tetrabromo bisphenol A (TBBPA). The hydroxyl and superoxide radicals dominated the photocatalytic reaction process of YMO/MAO for the degradation of CR, TC and TBBPA. The present work pioneers the potential application of YMO/MAO grafted by CO functional group as dyes, antibiotics and persistent organic pollutants (POPS) adsorption / degradation catalyst and further provides technical reference for the synthesis of others heterojunction photocatalysts.

Visible photocatalytic degradation of tetrabromobisphenol A by CuO-modified Ce2O3: Mechanisms and DFT studies

The widespread use of brominated flame retardants poses serious hazards to environment and health. In this study, CuO/Ce2O3 nanocomposites were synthesized by a coprecipitation method. Various characterization methods and density functional theory (DFT) calculations were used to analyze the composition and surface structure of material. Under visible light, the prototypical pollutant, namely, tetrabromobisphenol A (TBBPA) exhibited the highest degradation efficiency of 80.46% after 120 min with a CuO/Ce2O3 ratio of 1:20. The photocatalytic degradation mechanism of TBBPA in the CuO/Ce2O3 system was comprehensively investigated. Radical scavenging experiments showed that h+ is the primary active substance in TBBPA photodegradation, and·OH and·O2− are secondary contributors. Moreover, the Fukui index was used to predict the active site, and DFT methods were used to calculate the degradation mechanism of TBBPA. Combined gas chromatography/mass spectrometry and high-performance liquid chromatography-mass spectrometry showed that the possible degradation pathways of TBBPA were determined to be debromination, C–C bond breaking, and ring-opening. Ecotoxicity evaluation showed that degradation products have significantly lower acute toxicity than TBBPA. The excellent reusability and stability of CuO/Ce2O3 indicate that this system can be successfully applied in water treatment, which is of great significance for the environmentally-friendly removal of TBBPA.

Deglycosylation of Two Typical Plant-Generated Glycoconjugates of Tetrabromobisphenol A through In Vitro Digestion Processes

Tetrabromobisphenol A (TBBPA) is extensively detected in various environmental media. Its typical glycosylation products in plants, TBBPA mono-β-D-glucopyranoside (TBBPA MG) and TBBPA di-β-D-glucopyranoside (TBBPA DG), are likely to enter the human body through the oral route. The deglycosylation processes of TBBPA MG and TBBPA DG in both simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were studied. Results showed that 68% of TBBPA MG was transformed to TBBPA after 6 h incubation in gastrointestinal fluid, about 31% and 7% of TBBPA DG were transformed to TBBPA MG and TBBPA, respectively. In SGF, strong acid hydrolysis mainly contributed to the deglycosylation of TBBPA MG and TBBPA DG. In SIF, the bacteria, the synergistic effect of bacteria and pancreatin, and the bile led to the deglycosylation of TBBPA MG and TBBPA DG. The results indicated glycosylation products of TBBPA formed in vegetables or crops will be partially transformed into TBBPA and partially retained in the forms of glycosylation products in the human digestion system and may enter into the circulation system. These TBBPA glycoconjugates and the released TBBPA will cause health risks. This finding improved our understanding on the environmental fates, exposures, and health risks of TBBPA and its important phytometabolites.

GO accelerate iron oxides formation and tetrabromobisphenol A removal enhancement in the GO loaded NZVI system

Tetrabromobisphenol A (TBBPA) is an emerging persistent organic pollutant, which is very difficult to remove by common methods. In this study, the GO-load nanoscale zero-valent iron (NZVI/GO) was fabricated and optimized to improve the reaction rate and removal efficiency for TBBPA reliably and efficiently. The results showed that GO-load significantly reduced the self-aggregation of NZVI and the aggregate size decreased by 50.00% (1400–700 nm). Meanwhile, GO significantly improved the reaction rate kobs (1.11 ± 0.11 h−1) of TBBPA in the NZVI/GO system compared to the NZVI (0.40 ± 0.08 h−1) system, and this increment was more pronounced (177.5%) when the mass ratio of NZVI-to-GO reached 1.0 than other mass ratios. Furthermore, X-Ray Diffraction and X-ray photoelectron spectroscopy analysis suggested that the Fe2+ transformation was changed and enriched by the GO. Only magnetite (Fe3O4) was detected on the surface of NZVI, whereas the maghemite (γ-Fe2O3), hematite (α-Fe2O3), and Fe3O4 were detected on the interface of NZVI/GO, which further performed the complexation adsorption through the –OH of TBBPA. This specific complexation adsorption is another potential accelerated removal mechanism for TBBPA and intermediates within the NZVI/GO system. This research has put forward a new perspective for widening the application of TBBPA removal using the synergistic effect between GO and NZVI.

Tetrabromobisphenol A effects on differentiating mouse embryonic stem cells reveals unexpected impact on immune system.

Tetrabromobisphenol A (TBBPA) is a potent flame retardant used in numerous appliances and a major pollutant in households and ecosystems. In vertebrates, it was shown to affect neurodevelopment, the hypothalamic-pituitary-gonadal axis and thyroid signaling, but its toxicity and modes of actions are still a matter of debate. The molecular phenotype resulting from exposure to TBBPA is only poorly described, especially at the level of transcriptome reprogramming, which further limits our understanding of its molecular toxicity. In this work, we combined functional genomics and system biology to provide a system-wide description of the transcriptomic alterations induced by TBBPA acting on differentiating mESCs, and provide potential new toxicity markers. We found that TBBPA-induced transcriptome reprogramming affect a large collection of genes loosely connected within the network of biological pathways, indicating widespread interferences on biological processes. We also found two hotspots of action: at the level of neuronal differentiation markers, and surprisingly, at the level of immune system functions, which has been largely overlooked until now. This effect is particularly strong, as terminal differentiation markers of both myeloid and lymphoid lineages are strongly reduced: the membrane T cell receptor (Cd79a, Cd79b), interleukin seven receptor (Il7r), macrophages cytokine receptor (Csf1r), monocyte chemokine receptor (Ccr2). Also, the high affinity IgE receptor (Fcer1g), a key mediator of allergic reactions, is strongly induced. Thus, the molecular imbalance induce by TBBPA may be stronger than initially realized.

Developmental toxicity assessments for TBBPA and its commonly used analogs with a human embryonic stem cell liver differentiation model

Tetrabromobisphenol A (TBBPA) is widely used in industrial production as a halogenated flame retardant (HFR). Its substitutes and derivatives are also commonly employed as HFRs. Consequently, they can be frequently detected in environmental and human samples. The potential developmental toxicity of TBBPA and its analogs, particularly to the human liver, is still controversial or not thoroughly assessed. Therefore, in this study, we focused on the early stages of human liver development to explore the toxic effects of those HFRs, by using a human embryonic stem cell liver differentiation model. We concluded that nanomolar treatments (1, 10, and 100 nM) of those pollutants may not exert significant interference to liver development and functions. However, at 5 μM doses, TBBPA and its analogs severely affected liver functions, such as glycogen storage, and caused lipid accumulation. Furthermore, TBBPA-bis(allyl ether) showed the most drastic effects among the six compounds tested. Taken together, our findings support the view that TBBPA can be used safely, provided its amounts are strictly controlled. Nonetheless, TBBPA alternatives or derivatives may exhibit stronger adverse effects than TBBPA itself, and may not be safer choices for manufacturing applications when utilized in a large and unrestricted way.

Tetrabromobisphenol a exacerbates the overall radioactive hazard to zebrafish (Danio rerio)

The major health risks of dual exposure to two hazardous factors of plastics and radioactive contamination are obscure. In the present study, we systematically evaluated the combinational toxic effects of tetrabromobisphenol A (TBBPA), one of the most influential plastic ingredients, mainly from electronic wastes, and γ-irradiation in zebrafish for the first time. TBBPA (0.25 μg/mL for embryos and larvae, 300 μg/L for adults) contamination aggravated the radiation (6 Gy for embryos and larvae, 20 Gy for adults)-induced early dysplasia and aberrant angiogenesis of embryos, further impaired the locomotor vitality of irradiated larvae, and worsened the radioactive multiorganic histologic injury, neurobehavioural disturbances and dysgenesis of zebrafish adults as well as the inter-generational neurotoxicity in offspring. TBBPA exaggerated the radiative toxic effects not only by enhancing the inflammatory and apoptotic response but also by further unbalancing the endocrine system and disrupting the underlying gene expression profiles. In conclusion, TBBPA exacerbates radiation-induced injury in zebrafish, including embryos, larvae, adults and even the next generation. Our findings provide new insights into the toxicology of TBBPA and γ-irradiation, shedding light on the severity of cocontamination of MP components and radioactive substances and thereby inspiring novel remediation and rehabilitation strategies for radiation-injured aqueous organisms and radiotherapy patients.

Quantitative SERS Detection of TBBPA in Electronic Plastic Based on Hydrophobic Cu-Ag Chips.

Tetrabromobisphenol A (TBBPA) was one of the most widely used brominated flame retardants. However, it easily contaminates nature and harms the environment and human health during its production and use. Therefore, it is necessary to strictly control the content of TBBPA in electronics. Surface-enhanced Raman spectroscopy has the advantages of being fast and sensitive, but it is difficult to obtain the SERS spectra of TBBPA because the hydrophobic TBBPA molecule is difficult to approach with the hydrophilic surface of common noble metal SERS substrates. In the present work, a hydrophobic Cu-Ag chip was developed for the SERS detection of TBBPA. The integration of the hydrophobic interaction and the Ag-Br bonding promoted the adsorption of TBBPA on the Cu-Ag chip, allowing for SERS detection. It was observed that both the hydrophobicity and bimetallic composition of the Cu-Ag chip played important roles in the SERS detection of TBBPA. Under the optimized conditions, the low limit of detection of the established SERS method for TBBPA was 0.01 mg L−1, within a linear range of 0.1–10 mg L−1. Combined with ultrasonic-assisted extraction, the substrate could be used for the quantitative determination of TBBPA in electronic products. Compared with the HPLC-UV method used as a national standard, the relative error of the SERS method for quantifying the TBBPA content in a mouse cable and shell was ±3% and ±7.7%, respectively. According to the SERS results, the recovery of TBBPA in the spiked mouse shell was 95.6%.

Toxic responses of freshwater microalgae Chlorella sorokiniana due to exposure of flame retardants

Flame retardants, such as Tetrabromobisphenol A (TBBPA), Tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and tributyl phosphate (TBP), are frequently detected in surface water. However, the effects of FRs exposure on aquatic organisms especially freshwater microalgae are still unclear. In this study, the toxicities of TBBPA, TDCPP and TBP to microalgae Chlorella sorokiniana, in terms of growth inhibition, photosynthetic activity inhibition and oxidative damage, were investigated, and according ecological risks were assessed. The results showed that TBBPA, TDCPP and TBP had inhibitory effects on C. sorokiniana, with 96 h EC50 (concentration for 50% of maximal effect) values of 7.606, 41.794 and 49.996 mg/L, respectively. Fv/Fm decreased as the increase of exposure time under 15 mg/L TBBPA. Under 50 mg/L TDCPP and 80 mg/L TBP exposure, Fv/Fm decreased significantly after 24 h. However, Fv/Fm rose after 96 h, indicating that the damaged photosynthetic activity was reversible. The content of chlorophyll a decreased, as the increase of TBBPA concentration from 3 to 15 mg/L. However, chlorophyll a increased first and then decreased, as the increase of TDCPP and TBP concentrations from 0 to 50 mg/L and 0–80 mg/L, respectively. Results indicated that C. sorokiniana could use the phosphorus of TDCPP and TBP to ensure the production of chlorophyll a. The risen content of reactive oxygen species, malondialdehyde as well as superoxide dismutase activity indicated that exposure to FRs induced oxidative stress. Additionally, the risk quotients showed that tested FRs had ecological risks in natural waters or wastewaters. This study provides insights into the toxicological mechanisms of different FRs toward freshwater microalgae for better understanding of according environmental risks.