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1.
Chemosphere ; 287(Pt 1): 132120, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34523462

RESUMO

Water environmental pollution caused by spent batteries is a nonignorable environmental issue. In this study, the early life stage of zebrafish was employed to assess the environmental risk of spent batteries after exposure to 0, 1%, 2%, 5% and 10% spent battery extract for 120 h. Our results clearly indicated that spent battery extract can significantly decrease the survival rate, hatching rate and body length and increase heart rate. Moreover, spent battery extract exposure-induced zebrafish larvae generate oxidative stress and inhibit the mRNA transcriptional levels of heat shock protein (HSP70) and metallothionein (MT) genes. These results showed that the spent batteries not only affected the survival and development performance of zebrafish at an early life stage but also caused oxidative stress and interfered with the detoxification of zebrafish. This study provided novel insight into spent battery induced toxicity in the early life stage of fish.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Biomarcadores/metabolismo , Embrião não Mamífero/metabolismo , Larva , Estresse Oxidativo , Extratos Vegetais , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
2.
Ecotoxicol Environ Saf ; 227: 112883, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34653941

RESUMO

Arsenic (As) in the aquatic environment is a considerable environmental issue, previous studies have reported the toxic effects of low concentrations (≤ 150 µg/L) of As on fish. However, limited information is available regarding the impact of low levels of As on apoptosis. To evaluate this, zebrafish embryos were exposed to different concentrations (0, 25, 50, 75, and 150 µg/L) of As (arsenite [AsIII] and arsenate [AsV]) for 120 h. Our results indicated that low concentrations of AsIII exposure significantly inhibited the survival of zebrafish larvae, and significantly increased the transcription of Caspase-9 and Caspase-3, the ratio of Bax/Bcl-2 transcription, and protein levels of Caspase-3. In contrast, AsV decreased the ratios of Bax/Bcl-2 transcription and protein levels, as well as protein levels of Caspase-3. Our data demonstrated that AsIII and AsV exert different toxic effects, AsIII induced apoptosis via the mitochondrial pathway and the extrinsic pathway, while AsV induced apoptosis only via the mitochondrial pathway.


Assuntos
Arsênio , Animais , Apoptose , Arseniatos/toxicidade , Arsênio/toxicidade , Larva , Peixe-Zebra
3.
Ecotoxicol Environ Saf ; 200: 110743, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464441

RESUMO

Gill, as the organ of fish to contact most directly with xenobiotics, suffered more threat. To evaluate the impact of arsenite (AsIII) on the gill of fish, we measured the antioxidative responses (superoxide dismutase (SOD) and catalase (CAT) activities) and oxidative damage (malondialdehyde (MDA) content), histological changes and mRNA transcriptional responses of zebrafish gill, after exposure to AsIII (0, 10, 50, 100, and 150 µg L-1) solutions for 28 days. We found that AsIII increased the activities of CAT by 46%-87%, decreased the activities of SOD and the contents of MDA by 19% and 21%-32%. Furthermore, CuZnSOD and MnSOD mRNA transcription levels were also inhibited, decreasing by 62%-82% and 70%-77%. Besides, ≥ 100 µg L-1 AsIII also caused histological changes (a loss of mucus and desquamation in the surface of the epithelial cells) on zebrafish gill. These results showed that low concentrations of AsIII influenced biochemical and physiological performances of fish gill, which probably aggravates the toxic effect of AsIII on fish.


Assuntos
Arsenitos/toxicidade , Brânquias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Brânquias/metabolismo , Brânquias/patologia , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
4.
Environ Pollut ; 262: 114253, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32179223

RESUMO

Lead bioavailability in contaminated soils varies considerably depending on Pb speciation and sources of contamination. However, little information is available on bioavailability of Pb associated with different fractions. In this study, the Tessier sequential extraction was used to fractionate Pb in 3 contaminated soils to exchangeable (F1), carbonate-bound (F2), Fe/Mn oxides-bound (F3), organic-bound (F4), and residual fractions (F5). In addition, soil residues after F1-F2 extraction (F345), F1-F3 extraction (F45), and F1-F4 extraction (F5) were measured for Pb relative bioavailability (RBA) using a mouse kidney model. Based on the mouse model, Pb-RBA in the soils was 44-93%, which decreased to 43-89%, 28-75%, and 15-68% in the F345, F45, and F5 fractions, respectively. Based on Pb-RBA in the soil residues, Pb-RBA in different fractions was calculated based on a mass balance. The data showed that Pb-RBA was the highest (∼100%) in the exchangeable and carbonate fraction, and the lowest (15-68%) in the residual fraction. In addition, Pb in the first three fractions (F1-F3) contributed most (83-89%) to bioavailable Pb in contaminated soils. Our study shed light on oral bioavailability of Pb in contaminated soils of different fractions based on sequential extraction and provide important information for soil remediation.


Assuntos
Poluentes do Solo/análise , Disponibilidade Biológica , Poluição Ambiental , Mineração , Solo
5.
Ann Hum Biol ; 46(7-8): 601-605, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31790285

RESUMO

The autosomal short tandem repeat (STR) plays a unique role in population comparisons, phylogenetic reconstruction and migration history tracing. This study investigated the frequencies of 17 autosomal STR loci in the Han population from Wuxi, Eastern China, with the aim of expanding the available population information in human genetic databases and for forensic DNA analysis. The genetic polymorphisms of 17 STR loci were analysed in 5358 individuals of the Han population from Wuxi, Eastern China. Population comparisons including genetic distances, the neighbour-joining tree and multidimensional scaling plot were carried out between the Wuxi Han population and different ethnic groups. A total of 777 alleles at 17 autosomal STR loci were observed, with the corresponding allelic frequencies ranging from 0.0001-0.5210. The combined power of discrimination and exclusion for the 17 autosomal STR loci were 0.0000 and 0.000, respectively. Moreover, the phylogenetic analysis was performed between the Wuxi Han population and other relevant populations. The neighbour-joining tree and multidimensional scaling plot were generated based on Nei's standard genetic distance. Population comparisons indicated that the Wuxi Han population had the closest genetic relationship with the Hubei Han population, relative to the other populations, which mirrors the historical and geographical background of the populations compared.


Assuntos
Frequência do Gene , Repetições de Microssatélites , Polimorfismo Genético , China , Genética Forense , Humanos , Filogenia
6.
Environ Pollut ; 254(Pt A): 113022, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31408795

RESUMO

Arsenic (As) present in water is a nonignorable environmental issue, even at low concentrations (≤150 µg L-1). To evaluate the toxic effect of low concentrations of As, zebrafish at early life stage were exposed to 0, 25, 50, 75, or 150 µg L-1 AsIII for 120 h. Our results indicated that low concentration of AsIII decreased zebrafish larvae's survival rate to 85%, 89% and 86% at 50, 75 and 150 µg L-1. Furthermore, low concentrations of AsIII exposure caused oxidative stress (elevated superoxide dismutase (SOD) activity and influenced the mRNA transcriptional levels of Cu/ZnSOD and MnSOD) and damage (increased malondialdehyde levels). Meanwhile, zebrafish larvae regulated the mRNA transcription of metallothionein and heat shock protein 70 to alleviate toxicity caused by AsIII. These results revealed lower concentrations (≤150 µg L-1) of AsIII had a detriment effect on the survival of fish at early life stage, moreover, oxidative stress caused by AsIII posed potential risk for the zebrafish. This study provides novel insight into low concentration AsIII-induced toxicity in zebrafish.


Assuntos
Arsenitos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Arsênio/metabolismo , Arsenitos/metabolismo , Larva/efeitos dos fármacos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade , Transcrição Genética , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia
7.
Environ Toxicol ; 34(7): 781-787, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30884105

RESUMO

To evaluate the impact of DCAcAm on zebrafish gill, we measure the responses of antioxidant enzyme (superoxide dismutase, SOD), lipid peroxidation (malondialdehyde, MDA), ATPase (Na+ /K+ -ATPase and Ca2+ /Mg2+ -ATP) and histopathological changes of gill in adult zebrafish, after exposed to different concentrations of DCAcAm (0, 1, 10, 100, and 1000 µg L-1 ) for 30 days. Results indicated that DCAcAm first increased and then decreased SOD activity, and DCAcAm also lowered the activities of Na+ /K+ -ATPase and Ca2+ /Mg2+ -ATPase. These results indicated that high affinity of DCAcAm probably be a main factor, which can damage the structures of enzymes, thereby inhibiting the SOD and ATPase activities. Besides, histopathological investigation results also manifested that chronic exposure to DCAcAm can damage the gill tissues, disrupting the normal function of gills. We conclude that chronic exposure to DCAcAm was harmful to organisms, not only influence gill function, but also further cause damage on the gill tissues.


Assuntos
Acetamidas/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/patologia , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Antioxidantes/metabolismo , Exposição Ambiental , Brânquias/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo , Peixe-Zebra/anatomia & histologia , Peixe-Zebra/metabolismo
8.
Environ Pollut ; 245: 719-724, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30500751

RESUMO

2,6-dichlorobenzoquinone (2,6-DCBQ), an emerging disinfection by-production, frequently occurs in reclaimed water and drinking water. However, limited information was available regarding its toxicity. To evaluate its impact, zebrafish at early life stage were exposed to 0, 10, 30, 60, 90, or 120 µg L-1 2,6-BDCQ for 72 h. Our results indicated that 2,6-BDCQ decreased zebrafish's survival rate to 65% and 44% at 90 and 120 µg L-1 treatments and increased its aberration rate to 11% and 26% at 90 µg L-1 and 120 µg L-1 treatments. Besides, 2,6-BDCQ had adverse effect on its oxidative stress (elevated superoxide dismutase activity), lipid peroxidation (increased malondialdehyde levels), DNA damage (increased 8-hydroxydeoxyguanosine contents) and apoptosis (increased caspase-3 activity). Although lower concentrations (≤60 µg L-1) of 2,6-BDCQ didn't exhibit significant effect on its survival development or lipid peroxidation of zebrafish, they induced obvious DNA damage and apoptosis occurrence. These results revealed 2,6-BDCQ caused genotoxicity and cytotoxicity to zebrafish. This study provides novel insight into 2,6-DCBQ-induced toxicity in zebrafish.


Assuntos
Benzoquinonas/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Dano ao DNA , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra/genética
9.
Chemosphere ; 211: 648-652, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30098560

RESUMO

Low concentrations of arsenic (As) contamination in aquatic environment is a worldwide issue, which is of great concern. To evaluate the impact of low concentrations of As on zebrafish, we measured the growth, antioxidant enzymes including superoxide dismutase (SOD) and catalase (CAT), oxidative damage (malondialdehyde, MDA) and apoptosis-related genes (nrf2, p53 and c-jun) of adult zebrafish after exposing to different AsIII concentrations (0, 10, 50, 100 or 150 µg L-1) for 28 d. Results indicated that exposure to low AsIII concentrations decreased the zebrafish weight by 14%, increased the activities of SOD and CAT by 23-41% and 31-59%, decreased the contents of MDA by 29-54%, and modulated transcription of apoptosis related genes. Our study showed that chronic exposure to AsIII concentrations <150 µg L-1 generated oxidative stress and damage on zebrafish, and altered apoptosis-related genes in zebrafish.


Assuntos
Apoptose/genética , Arsenitos/química , Peixe-Zebra/genética , Animais , Estresse Oxidativo
10.
Chemosphere ; 186: 580-587, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28813693

RESUMO

Arsenic contamination in drinking water is a worldwide issue, posing threat to human health. Arsenic is an endocrine system disruptor, however, limited information is available regarding its long-term effects on thyroid endocrine system at low exposure. In this study, we assessed the thyroid toxicity of arsenate (AsV) and arsenite (AsIII) at 10-100 µg L-1 in juvenile mice after 8-week of exposure via drinking water. After 1-2 week, AsV and AsIII had little influence on thyroxine (T4) level (56.3-64.7 µg L-1) in mouse blood compared to control mice at 57.3-60.7 µg L-1. However, after 4-8 weeks, 10 µg L-1 AsIII or AsV increased T4 levels to 83.8-88.8 µg L-1 compared to control treatment at 77.2-80.0 µg L-1, while 100 µg L-1 AsV or AsIII decreased T4 levels except for 100 µg L-1 AsIII for 8 weeks. Based on transmission electron microscopy, exposure to 100 µg L-1 AsIII or AsV for 8 weeks caused thyroid gland damage. In addition, exposure to AsV or AsIII at 10 or 100 µg L-1 impacted gene transcription of hypothalamic-pituitary-thyroid axis including thyroid stimulating hormone and iodothyronine deiodinases. Our data demonstrated that exposing to low levels of AsIII or AsV disrupted T4 homeostasis, influenced the related gene transcription and damaged the thyroid glands in juvenile mice.


Assuntos
Arseniatos/toxicidade , Arsenitos/toxicidade , Expressão Gênica/efeitos dos fármacos , Compostos de Sódio/toxicidade , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/sangue , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Água Potável/normas , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Hormônios Tireóideos/genética
11.
J Hazard Mater ; 339: 256-263, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28654790

RESUMO

Hand-to-mouth activity is an important pathway for children's exposure to contaminated soils, which is often co-contaminated by Pb and As in mining and smelting sites. To reduce soil Pb risk to humans by oral exposure, phosphate amendments have been used to reduce Pb relative bioavailability (RBA), but its efficiency has not been investigated using validated in vitro assays nor its influence on As-RBA. Here, 5 contaminated soils (A-E) were amended with 0.5% phosphoric acid (PA) to study its effect on Pb- and As- RBA using a newly-developed mouse kidney model and bioaccessibility using 4 in vitro assays including UBM, SBRC, IVG, and PBET. Based on the mouse kidney model, Pb-RBA in PA-amended soils decreased from 14.2-62.5% to 10.1-29.8%. In contrast, As-RBA decreased from 26.5% to 15.9% in soil B but increased from 27.5 to 41.2% in soil D, with changes being insignificant in 3 other soils (35.8-58.8 to 28.1-61.1%). When assessing Pb bioaccessibility in PA-amended soils, decreased bioaccessibility were found using PBET and SBRC. For As, its bioaccessibility increased in PA-amended soils, inconsistent with in vivo data. Our results shed light on the importance of method selection to assess risk in Pb- and As-contaminated soils amended with phosphate.


Assuntos
Arsênio/farmacocinética , Rim/metabolismo , Chumbo/farmacocinética , Fosfatos/química , Poluentes do Solo/farmacocinética , Animais , Disponibilidade Biológica , Feminino , Camundongos Endogâmicos BALB C
12.
Environ Sci Technol ; 51(8): 4689-4696, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28299926

RESUMO

A steady-state mouse model was developed to determine arsenic (As) relative bioavailability (RBA) in rice to refine As exposure in humans. Fifty-five rice samples from 15 provinces of China were analyzed for total As, with 11 cooked for As speciation and bioavailability assessment. Arsenic concentrations were 38-335 µg kg-1, averaging 133 µg kg-1, with AsIII being dominant (36-79%), followed by DMAV (18-58%) and AsV (0.5-16%). Following oral doses of individual As species to mice at low As exposure (2.5-15 µg As per mouse) over a 7-d period, strong linear correlations (R2 = 0.99) were observed between As urinary excretion and cumulative As intake, suggesting the suitability and sensitivity of the mouse bioassay to measure As-RBA in rice. Urinary excretion factor for DMAV (0.46) was less than inorganic As (0.63-0.69). As-RBA in cooked rice ranged from 13.2 ± 2.2% to 53.6 ± 11.1% (averaging 27.0 ± 12.2%) for DMAV and 26.2 ± 7.0% to 49.5 ± 4.7% (averaging 39.9 ± 8.3%) for inorganic As. Calculation of inorganic As intake based on total inorganic As in rice overestimated As exposure by 2.0-3.7 fold compared to that based on bioavailable inorganic As. For accurate assessment of the health risk associated with rice consumption, it is important to consider As bioavailability especially inorganic As in rice.


Assuntos
Arsênio , Oryza , Animais , Arsênio/urina , Bioensaio , Disponibilidade Biológica , Contaminação de Alimentos , Saúde , Humanos , Camundongos , Oryza/química
13.
Environ Res ; 156: 834-842, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28318508

RESUMO

As a replacement for polybrominated diphenyl ethers, bis-(2-ethylhexyl) tetrabromophthalate (TBPH) is widely used as a novel flame retardant and has been detected in many environmental matrix including human blood. TBPH can be metabolized into mono-(2-ethyhexyl) tetrabromophthalate (TBMEHP) by carboxylesterase. However, their adverse effects on human vascular endothelium and their potential impacts on human cardiovascular disease are unknown. In this study, their adverse effects and associated molecular mechanisms on human vascular endothelial cells (HUVECs) were investigated. A concentration-dependent inhibition on HUVECs' viability and growth was observed for TBMEHP but not for TBPH. TBMEHP induced a marked G0/G1 cell cycle arrest and robust cell apoptosis at 1µg/mL by inducing expression of p53, GADD45α and cyclin dependent kinase (CDK) inhibitors (p21and p27) while suppressing the expression of cyclin D1, CDK2, CDK6, and Bcl-2. Unlike TBMEHP, TBPH caused early apoptosis after G2/M phase arrest only at 10µg/mL via up-regulation of p21 and down-regulation of CDK2 and CDK4. TBMEHP decreased mitochondrial membrane potential and increased caspase-3 activity at 1µg/mL, suggesting that activation of p53 and mitochondrial pathway were involved in the cell apoptosis. The data showed that TBPH and TBMEHP induced different cell cycle arrest and apoptosis through different molecular mechanisms with much higher toxicity for TBMEHP. Our study implies that the metabolites of TBPH, possibly other novel brominated flame retardants, may be of potential concern for human cardiovascular disease.


Assuntos
Retardadores de Chama/toxicidade , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Ácidos Ftálicos/toxicidade , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Nucleares/genética , Medição de Risco , Proteína Supressora de Tumor p53/genética
14.
J Hazard Mater ; 326: 94-100, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27992800

RESUMO

Mouse is an acceptable animal model to measure lead (Pb) relative bioavailability (RBA) in contaminated soils; however, there is a lack of comparisons among Pb-RBA measurements based on different endpoints and dosing approaches. In this study, 12 soils (47.8-8123mg Pbkg-1) were assessed for Pb-RBA using Pb accumulation in mouse liver, kidneys, and/or femur following a 10-d steady state soil dose via diet, with 6 soils being measured using mouse bioassays with area under the mouse blood Pb concentration time curve (AUC) following a single gavaged dose as the endpoint. Based on individual endpoints of the steady state method, Pb-RBA in soils was 2.1-83.4%, being generally consistent among liver, kidneys, and femur with strong linear correlations between them (r2=0.74-0.89). To compensate variation in Pb distribution among different tissues, Pb-RBA was further calculated using a combined endpoint (e.g., sum of Pb accumulation in liver, kidneys, and femur). Compared to Pb-RBA based on individual tissue showing relative standard deviation (RSD) of 11.9-15.8%, Pb-RBA using the combined endpoint showed lower RSD (10.8%), thereby being more robust. For the 6 soils with Pb-RBA based on both mouse single gavaged and steady state dosing approach, no significant difference was observed; however, steady state approach was more repeatable among animals with lower RSD (11.4% vs. 34.5%). To ensure robustness of in vivo data, the steady state dosing approach with Pb accumulation in combined tissues is recommended.


Assuntos
Chumbo/farmacocinética , Poluentes do Solo/farmacocinética , Solo/química , Animais , Disponibilidade Biológica , Determinação de Ponto Final , Exposição Ambiental , Poluição Ambiental , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Tecidual
15.
Environ Int ; 95: 61-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27502899

RESUMO

Due to its toxicity as a carcinogen and wide distribution in the environment, arsenic (As) exposure in humans is of public concern globally. Many studies have manifested that As exposure induces cancers besides pathological effects in humans. Animal studies showed that chronic As exposure induces serious neurological effects. Based on recent studies, researchers proposed that As, including arsenate (AsV) and arsenite (AsIII), is also an endocrine disruptor. This review discusses the mechanisms of As toxicity on three endocrine systems including gonadal, adrenal and thyroid endocrine systems. Arsenic methylation and oxidative stress are responsible for As-induced disorders of endocrine systems, however, strong binding of AsIII to thiols also play an important role. Some studies showed AsV toxicity on endocrine systems, but mechanistic investigation is lacking. Research is needed to look into their toxicity mechanisms to help cure the illnesses caused by As-induced endocrine system disorders.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Arsênio/toxicidade , Gônadas/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Animais , Arseniatos , Arsênio/metabolismo , Arsenitos , Humanos , Metilação
16.
Environ Int ; 94: 600-606, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27346741

RESUMO

In vitro assays have been developed to determine metal bioaccessibility in contaminated soils; however, their application to Cd is limited. To assess their suitability to determine Cd relative bioavailability (RBA), Cd-RBA in 12 contaminated soils containing 3.00-296mgkg(-1) Cd were determined using a mouse model and compared with Cd bioaccessibility data based on four assays including the UBM, SBRC, IVG, and PBET. After being administered feed amended with soil or CdCl2 for 10-day, the Cd concentrations in the mouse liver and/or kidneys were used as biomarkers to estimate Cd-RBA. Cd-RBA was comparable at 34-90% and 40-78% based on mouse liver and kidneys with RSD of 7.10-8.99%, and 37-84% based on mouse liver plus kidneys with lower RSD of 5.8%. Cadmium bioaccessibility in soils varied with assays, with 61-99, 59-103, 54-107, and 35-97% in the gastric phase and 20-56, 38-77, 42-88, and 19-64% in the intestinal phase of the UBM, SBRC, IVG and PBET assays. Based on the combined biomarker of liver plus kidneys, better correlation was observed for PBET (r(2)=0.61-0.70) than those for IVG, UBM and SBRC assays (0.12-0.52). The monthly Cd intake in children was 0.24-23.9µgkg(-1) using total Cd concentration in soils, which was reduced by 43% to 0.18-12.3µgkg(-1) using bioavailable Cd. Our data suggest it is important to consider Cd-RBA to assess risk associated with contaminated soils and the PBET may have potential to predict Cd-RBA in contaminated soils.


Assuntos
Bioensaio , Cádmio , Poluentes do Solo , Animais , Bioensaio/métodos , Bioensaio/normas , Disponibilidade Biológica , Cádmio/análise , Cádmio/farmacocinética , Modelos Animais de Doenças , Exposição Ambiental/análise , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Camundongos , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética
17.
Environ Int ; 92-93: 348-56, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27131017

RESUMO

Human corneal epithelial (HCE) cells are continually exposed to dust in the air, which may cause corneal epithelium damage. Both water and organic soluble contaminants in dust may contribute to cytotoxicity in HCE cells, however, the associated toxicity mechanisms are not fully elucidated. In this study, indoor dust from residential houses and commercial offices in Nanjing, China was collected and the effects of organic and water soluble fraction of dust on primary HCE cells were examined. The concentrations of heavy metals in the dust and dust extracts were determined by ICP-MS and PAHs by GC-MS, with office dust having greater concentrations of heavy metals and PAHs than house dust. Based on LC50, organic extract was more toxic than water extract, and office dust was more toxic than house dust. Accordingly, the organic extracts induced more ROS, malondialdehyde, and 8-Hydroxydeoxyguanosine and higher expression of inflammatory mediators (IL-1ß, IL-6, and IL-8), and AhR inducible genes (CYP1A1, and CYP1B1) than water extracts (p<0.05). Extracts of office dust presented greater suppression of superoxide dismutase and catalase activity than those of house dust. In addition, exposure to dust extracts activated NF-κB signal pathway except water extract of house dust. The results suggested that both water and organic soluble fractions of dust caused cytotoxicity, oxidative damage, inflammatory response, and activation of AhR inducible genes, with organic extracts having higher potential to induce adverse effects on primary HCE cells. The results based on primary HCE cells demonstrated the importance of reducing contaminants in indoor dust to reduce their adverse impacts on human eyes.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Córnea/citologia , Poeira/análise , Células Epiteliais/efeitos dos fármacos , Células Cultivadas , China , Citocromo P-450 CYP1A1/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta , Transdução de Sinais
18.
Environ Int ; 89-90: 30-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26826360

RESUMO

Human cornea is highly susceptible to damage by dust. Continued daily exposure to housedust has been associated with increasing risks of corneal injury, however, the underlying mechanism has not been elucidated. In this study, a composite housedust sample was tested for its cytotoxicity on primary human corneal epithelial (PHCE) cells, which were exposed to dust at 5-320µg/100µL for 24h. PHCE cell viability showed a concentration-dependent toxic effect, attributing to elevated intracellular ROS. Moreover, when exposed at >20-80µg/100µL, dust-induced oxidative damage was evidenced by increased malondialdehyde and 8-hydroxy-2-deoxyguanosine (1.3-2.3-fold) and decreased antioxidative capacity (1.6-3.5-fold). Alteration of mRNA expression of antioxidant enzymes (SOD1, CAT, HO-1, TRXR1, GSTM1, GSTP1, and GPX1) and pro-inflammatory mediators (IL-1ß, IL-6, IL-8, TNF-α, and MCP-1) were also observed. Furthermore, the mitochondrial transmembrane potential was dissipated from 9.2 to 82%. Our results suggested that dust-induced oxidative stress probably played a vital role in the cytotoxicity in PHCE cells, which may have contributed to dust-induced impairment of human cornea.


Assuntos
Poluentes Atmosféricos/toxicidade , Córnea/efeitos dos fármacos , Citocinas/imunologia , Poeira/análise , Células Epiteliais/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Córnea/imunologia , Córnea/metabolismo , Citocinas/genética , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Humanos , Cultura Primária de Células
19.
J Hazard Mater ; 303: 76-82, 2016 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-26513566

RESUMO

Arsenic (As) contamination in aquatic environment adversely impacts aquatic organisms. The present study assessed the toxicity of different As species and concentrations on bighead carp (Hypophthalmichthys nobilis) at early life stage, a major fish in Yangtze River, China. We measured the changes in embryo and larvae survival rate, larvae aberration, concentrations of thyroid hormone thyroxine, and transcription levels of thyroid hormone receptors (TRs) in fish larvae after exposing to arsenite (AsIII) or arsenate (AsV) at 0, 10, 30, 50, 100, or 150 µg L(-1) for 78 h. As concentrations ≤ 150 µg L(-1) had limited effect on embryo survival rate (6-8% inhibition), but larvae survival rate decreased to 53-57% and larvae aberration rate increased to 20-24% after As exposure. Moreover, thyroxine levels elevated by 23% and 50% at 100 µg L(-1) AsIII and 150 µg L(-1) AsV. Besides, AsIII and AsV decreased the transcriptional levels of TRα by 72 and 53%, and TRß by 91 and 81% at 150 µg L(-1) As. Our data showed that AsIII and AsV had limited effect on carp embryo survival, but they were both toxic to carp larvae, with AsIII showing more effect than AsV. As concentrations <150µg L(-1) adversely influenced the development of bighead carp larvae and disturbed their thyroid hormone homeostasis.


Assuntos
Arsênio/toxicidade , Carpas/metabolismo , Crescimento/efeitos dos fármacos , Receptores dos Hormônios Tireóideos/biossíntese , Hormônios Tireóideos/biossíntese , Transcrição Genética/efeitos dos fármacos , Animais , Carpas/crescimento & desenvolvimento , Embrião não Mamífero , Larva/crescimento & desenvolvimento , Larva/metabolismo
20.
Environ Sci Technol ; 50(1): 453-61, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26595746

RESUMO

Different animals and biomarkers have been used to measure the relative bioavailability of arsenic (As-RBA) in contaminated soils. However, there is a lack of As-RBA comparison based on different animals (i.e., swine and mouse) and biomarkers [area under blood As concentration curve (AUC) after a single gavaged dose vs steady-state As urinary excretion (SSUE) and As accumulation in liver or kidney after multiple doses via diet]. In this study, As-RBA in 12 As-contaminated soils with known As-RBA via swine blood AUC model were measured by mouse blood AUC, SSUE, and liver and kidney analyses. As-RBA ranges for the four mouse assays were 2.8-61%, 3.6-64%, 3.9-74%, and 3.4-61%. Compared to swine blood AUC assay (7.0-81%), though well correlated (R(2) = 0.83), the mouse blood AUC assay yielded lower values (2.8-61%). Similarly, strong correlations of As-RBA were observed between mouse blood AUC and mouse SSUE (R(2) = 0.86) and between urine, liver, and kidney (R(2) = 0.75-0.89), suggesting As-RBA was congruent among different animals and end points. Different animals and biomarkers had little impact on the outcome of in vivo assays to validate in vitro assays. On the basis of its simplicity, mouse liver or kidney assay following repeated doses of soil-amended diet is recommended for future As-RBA studies.


Assuntos
Arsênio , Poluentes do Solo , Animais , Área Sob a Curva , Arsênio/sangue , Arsênio/farmacocinética , Disponibilidade Biológica , Poluição Ambiental/análise , Camundongos , Modelos Animais , Poluentes do Solo/sangue , Poluentes do Solo/farmacocinética , Suínos
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