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1.
Chemosphere ; 357: 142096, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663676

RESUMO

Cypermethrin (CYP) is a chemical of emerging concern which has persistent and bioaccumulating impacts as it can be found extensively in freshwater ecosystem and agricultural products. It has exposure risk and toxic effects over human edible fish, as common carp. Four groups were designed for toxicity assessment and detoxification approach: control group (CL), CYP exposure group (CYP), CYP + 10% M. oleifera leaves and 10% M. oleifera seeds (CMO group), 10% M. oleifera leaves and 10% M. oleifera seeds (MO group). Trial period was forty days during which cohort of 240 fish in CYP and CMO group was exposed to 1/5 of 96h LC50 of CYP (0.1612 µg/L). CYP-exposed carp exhibited lower growth parameters, but carp fed with 10% M. oleifera seeds and leaves showed significant improvement in growth rate (SGR, RGR) and weight gain (WG) as compared to the control group. CYP exposure negatively affected haemato-biochemical parameters. Moreover, CYP exposure also led to oxidative stress, damaged immunological parameters, genotoxicity and histopathological damage in liver and intestinal cells. Whereas, M. oleifera supplementation has ameliorated these conditions. Thereby, supplementation with M. oleifera is potential and novel therapeutic detoxication approach for common carp and human health against persistent and bioaccumulating emerging chemicals.


Assuntos
Carpas , Inseticidas , Piretrinas , Poluentes Químicos da Água , Testes de Toxicidade Crônica , Inseticidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Moringa oleifera , Suplementos Nutricionais , Sementes , Folhas de Planta , Inativação Metabólica , Piretrinas/toxicidade
2.
Sci Total Environ ; 872: 162262, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36801337

RESUMO

In vitro assays are widely proposed as a test alternative to traditional in vivo standard acute and chronic toxicity tests. However, whether toxicity information derived from in vitro assays instead of in vivo tests could provide sufficient protection (e.g., 95 % of protection) for chemical risks remain evaluated. To investigate the feasibility of zebrafish (Danio rerio) cell-based in vitro test method as a test alternative, we comprehensively compared sensitivity differences among endpoints, among test methods (in vitro, FET and in vivo), and between zebrafish and rat (Rattus norvegicus), respectively using chemical toxicity distribution (CTD) approach. For each test method involved, sublethal endpoints were more sensitive than lethal endpoints for both zebrafish and rat, respectively. Biochemistry (zebrafish in vitro), development (zebrafish in vivo and FET), physiology (rat in vitro) and development (rat in vivo) were the most sensitive endpoints for each test method. Nonetheless, zebrafish FET test was the least sensitive one compared to its in vivo and in vitro tests for either lethal or sublethal responses. Comparatively, rat in vitro tests considering cell viability and physiology endpoints were more sensitive than rat in vivo test. Zebrafish was found to be more sensitive than rat regardless of in vivo or in vitro tests for each pairwise endpoint of concern. Those findings indicate that zebrafish in vitro test is a feasible test alternative to zebrafish in vivo and FET test and traditional mammalian test. It is suggesting that zebrafish in vitro test can be optimized by choosing more sensitive endpoints, such as biochemistry to provide sufficient protection for zebrafish in vivo test and to establish applications of zebrafish in vitro test in future risk assessment. Our findings are vital for evaluating and further application of in vitro toxicity toxicity information as an alternative for chemical hazard and risk assessment.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Ratos , Animais , Peixe-Zebra/fisiologia , Embrião não Mamífero , Testes de Toxicidade Crônica , Medição de Risco , Técnicas In Vitro , Mamíferos
3.
Chemosphere ; 312(Pt 1): 137028, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36323386

RESUMO

Fluoxetine, a common pharmaceutical used as an antidepressant, is already considered potentially hazardous to biota due to its increasing use and detection in European, North American, and Asian rivers. We studied the effects of fluoxetine on Daphnia magna, as we hypothesized that fluoxetine might have harmful effects, short and long-term, at different levels: survival, behaviour, and reproduction (offspring production). We applied two different approaches: (i) a scenario at environmentally relevant concentrations (0.1-1.0 µg/L) and (ii) a scenario simulating a future worsening of contamination (1-800 µg/L) until the reach of lethal concentrations. In the former, we examined whether there are multigenerational effects on reproduction and on the avoidance/colonisation behaviour in previously exposed populations. In the latter, three responses were assessed: survival, avoidance behaviour and reproduction. We did not detect differences in the reproduction output of D. magna among the treatments over the three generations examined. Irrespective of the multigenerational treatment, D. magna colonised the environments with fluoxetine in a similar way. In the second scenario, we determined the lethal concentration for 50% of the population (96 h-LC50 = 365 µg/L), which, in spite of the toxic effect, was attractive to organisms during the avoidance tests (24 h); in fact, D. magna were attracted (no repellence) even to the highest concentrations of fluoxetine tested (800 µg/L). Lastly, in a 21-day chronic toxicity test the reproduction output of D. magna increased with higher concentrations of fluoxetine. This effect might be related to the fact that the organisms in the contaminated treatment began their first reproduction earlier, when compared to that in the control treatments. In conclusion, this study discusses an identified hazard for aquatic biota due to the fluoxetine attraction effect and a predictive assessment of the consequences expected if its indiscriminate use increases.


Assuntos
Daphnia , Poluentes Químicos da Água , Animais , Fluoxetina/toxicidade , Poluentes Químicos da Água/toxicidade , Reprodução , Testes de Toxicidade Crônica
4.
Environ Toxicol Pharmacol ; 89: 103789, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34954125

RESUMO

There is limited information on fluoride toxicity and risk overview on ecotoxicological risks to aquatic invertebrate populations particularly molluscan taxa. This necessitated the assessment of toxicity responses in the freshwater snail, Bellamya bengalensis exposed to environmentally relevant concentrations of sodium fluoride. Under lethal exposures (150, 200, 250, 300, 400 and 450 mg/l), the median lethal concentrations (LC50) were determined to be 422.36, 347.10, 333.33 and 273.24 mg/l for B. bengalensis at 24, 48, 72 and 96 h respectively. The rate of mortality of the snails was increased significantly with elevated concentrations of the toxicant. The magnitude of toxicity i.e., toxicity factor at different time scale was also higher with increased exposure duration. Altered behavioural changes i.e., crawling movement, tentacle movement, clumping tendency, touch reflex and mucous secretion in exposed snail with elevated concentrations and exposure duration. Similarly, oxygen consumption rate of the treated snail also lowered significantly during 72 and 96 h of exposure. Under 30-day chronic exposures (Control-0.00 mg/L; T1-27.324 mg/L; T2-54.648 mg/L), protein concentrations in gonad and hepatopancreas of exposure groups was significantly lowered. Chronic exposures also revealed lowered haemocytes counts in exposure groups. The potential for loss of coordination, respiratory distress and physiological disruption in organisms exposed to environmentally relevant concentrations of fluoride was demonstrated by this study. The estimation and magnitude of toxicity responses are necessary for a more accurate estimation of ecological risks to molluscan taxa and invertebrate populations under acute and chronic fluoride exposures in the wild.


Assuntos
Caramujos/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Biomarcadores , Gônadas/química , Hemócitos/efeitos dos fármacos , Hepatopâncreas/química , Consumo de Oxigênio/efeitos dos fármacos , Proteínas/análise , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
5.
Pak J Pharm Sci ; 34(4(Supplementary)): 1485-1498, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34799324

RESUMO

Digas colic drops (DCD-684) a polyherbal formulation containing Carum carvi, Foeniculum vulgare, Mentha arvensis, Mentha piperita and Zingiber officinale is widely used in Pakistan against gastrointestinal ailments including infantile colic. The DCD-684 (0.03-3ml/kg.bw) administered orally in acute (7-days) and sub-acute toxicity (14-days) tests, displayed neither mortality nor toxicological changes in physical, behavioral, biochemical and histopathological parameters. In chronic study (90-days), DCD-684 (0.3-12ml/kg.bw) also revealed no changes. However, at 18 and 36 ml/kg.bw, liver demonstrated mild inflammation correlating with raised aspartate transaminase (AST), alkaline phosphatase (ALP) and alpha fetoprotein (AFP) levels. Increased levels of urea and inflamed renal parenchyma indicated mild nephro-toxicity with high alanine aminotransferase (ALT) at 36ml/kg.bw. The LD50 of DCD-684 in mice was 27.5 ml/kg.bw. In hepatocytes at 36ml/kg.bw, elevated mRNA expression of pro-inflammatory chemokines and cytokines were evident. DCD-684 neither damaged DNA nor induced cytotoxicity in micronucleus assay. In conclusion, polyherbal DCD-684 caused neither hepatic, renal, genotoxicity nor any undesirable effect in mice. Higher doses administered for 90 days showed mild toxic effects with no sign of necrosis, fibrosis or genotoxicity. Thus, in mice DCD-684 demonstrated a wide margin of safety to be used for the relief of infantile colic.


Assuntos
Fármacos Gastrointestinais/toxicidade , Medicina Tradicional , Plantas Medicinais/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Animais , Citocinas/genética , Citocinas/metabolismo , Esquema de Medicação , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Testes para Micronúcleos , Paquistão
6.
J Oleo Sci ; 70(12): 1749-1759, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34759114

RESUMO

Refined red palm-pressed mesocarp olein (PPMO) is recovered from palm-pressed mesocarp fiber, which is a by-product from palm oil mill. Its utilization in food industry is extremely limited even though it contains various phytonutrients. Thus, this study aimed to evaluate its toxicity effects by using the male Sprague-Dawley rat model. The rats were administered with a single dose of 2 g/kg PPMO in an acute toxicity study while administered with 2, 1, or 0.5 g/kg PPMO daily for 28 days in a sub-chronic toxicity study. The mortality, oral LD50 value, clinical observation, body and organ weight, hematological and biochemical analyses, pathological and histopathological examinations were assessed. The overall outcomes indicated that PPMO is non-toxic up to 2 g/kg and considered safe to be used in food application, especially as functional food ingredient and supplement attributed to its phytonutrients. Besides, this study provides an insight in alternative utilization of the wastes from palm oil mill.


Assuntos
Análise de Perigos e Pontos Críticos de Controle/métodos , Óleo de Palmeira/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Animais , Peso Corporal/efeitos dos fármacos , Suplementos Nutricionais , Inocuidade dos Alimentos , Alimento Funcional , Dose Letal Mediana , Masculino , Tamanho do Órgão/efeitos dos fármacos , Óleo de Palmeira/administração & dosagem , Óleo de Palmeira/química , Compostos Fitoquímicos , Ratos Sprague-Dawley , Resíduos Sólidos
7.
Eur J Pharm Biopharm ; 160: 1-8, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484865

RESUMO

Dissolving microneedles (DMNs) are widely used in drug delivery systems since they are based on one-step application, which is simple and convenient for patients, especially for the patients such as diabetes who need daily or long-term self-administration. In general, the matrix materials of DMNs are water-soluble materials that can release the encapsulated drugs gradually by dissolving in the skin without generating sharp needle waste. However, the matrix materials of DMNs will also leave in the skin after application. Thus, it is vital to evaluate whether the matrix material of DMNs dissolved in the skin will cause health risks such as toxicity to the body or some skin-related complications to patients who frequent or long-term administration. In this work, PVA, as one of the typical matrix materials of DMNs, was selected to prepare the DMNs to research the safety of PVA-based MNs to the body after being dissolved in the skin. Briefly, in a 160 - days trial, the healthy mice were daily administrated by PVA MNs. The results showed that PVA materials mainly accumulated in the skin tissues of mice after dissolving and the concentration of PVA in the insertion sites gradually decreased and was almost undetectable at 6 days after administration. The observation of general conditions, blood hematological analysis and histological examinations of the mice demonstrated that the PVA-based MNs do not cause appreciable toxicity to the healthy mice after daily insertion in a 160 - days trial. Altogether, these results encourage further studies of PVA MNs for biomedical applications and support translation of PVA-based DMNs from pre-clinical development into clinical trials.


Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Agulhas/efeitos adversos , Álcool de Polivinil/efeitos adversos , Administração Cutânea , Animais , Feminino , Camundongos , Modelos Animais , Álcool de Polivinil/farmacocinética , Pele/metabolismo , Distribuição Tecidual , Testes de Toxicidade Crônica
8.
J Ethnopharmacol ; 263: 113184, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-32736055

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Longan (Dimocarpus longan Lour.) is one of the most popular subtropical fruits. Various parts of longan, including seeds, pericarp and pulp, have long been used in traditional medicine in China, Thailand and other Asian countries. The pulp has high sugar, vitamin and mineral content as well as bioactive components. The seeds and pericarp have also been reported to contain beneficial polyphenolic compounds. Longan sugar extract from pulp (LGSP) is prepared as a conventional sugar product. Longan sugar extract from whole longan fruit (LGSW) is also offered as a health food and as a medicinal product. AIM OF THE STUDY: The objective of this study was to identify and compare potential health hazards of both LGSW and LGSP by testing for acute and chronic oral toxicity in rats. MATERIALS AND METHODS: In acute toxicity testing, an oral dose (20 g/kg) of either LGSW or LGSP was administered to groups of rats. Mortality and clinical signs of toxicity were observed for 24 h, and then daily for a total of 14 days. In the chronic toxicity test, either LGSW (1, 2.5 and 5 g/kg/day) or LGSP (5 g/kg/day) was administered orally for a period of 180 days. After that treatment period, the rats in the satellite groups which received the highest doses of either LGSW or LGSP were observed for an additional 28 days. The rats then underwent clinical observation, body and organ weight measurement, hematological and biochemical analyses, and histopathological examination. RESULTS: In the acute toxicity study, the oral administration of LGSP or LGSW in either pellet or syrup formulations did not cause mortality or any pathological abnormalities. In the chronic toxicity study, neither LGSW nor LGSP resulted in death or in any changes in behavior of the rats. All hematological and serum biochemical values of both the LGSW- and LGSP-treated groups were within the normal ranges. No histopathological abnormalities of any internal organs were observed. CONCLUSION: The safety of longan sugar extract made from whole fruit (pulp, seeds and pericarb) is comparable to that of longan sugar extract made from pulp alone.


Assuntos
Frutas , Extratos Vegetais/toxicidade , Sapindaceae/toxicidade , Açúcares/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Açúcares/isolamento & purificação
9.
Environ Toxicol Chem ; 39(8): 1578-1589, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32388890

RESUMO

There is global concern regarding the fate and effects of microplastics in the environment, particularly in aquatic systems. In the present study, ethylene acrylic acid copolymer particles were evaluated in a chronic toxicity study with the aquatic invertebrate Daphnia magna. The study design included a natural particle control treatment (silica) to differentiate any potential physical effects of a particle from the intrinsic toxicity of the test material. In addition to the standard endpoints of survival, growth, and reproduction, the transcriptomic profiles of control and ethylene acrylic acid copolymer-exposed D. magna were evaluated at the termination of the 21-d toxicity study. No significant effects on D. magna growth, survival, or reproduction were observed in comparison with both particle and untreated control groups. Significant transcriptomic alterations were induced at the highest treatment level of 2.3 × 1012 particles of the ethylene acrylic acid copolymer/L in key pathways linked to central metabolism and energy reserves, oxidative stress, and ovulation and molting, indicating a global transcriptomic response pattern. To put the results in perspective is challenging at this time, because, to date, microplastic environmental monitoring approaches have not been equipped to detect particles in the nanosize range. However, our results indicate that ethylene acrylic acid copolymer microplastics in the upper nanosize range are not expected to adversely affect D. magna growth, survival, or reproductive outcomes at concentrations of up to 1012 particles/L. Environ Toxicol Chem 2020;39:1578-1589. © 2020 SETAC.


Assuntos
Daphnia/genética , Monitoramento Ambiental , Microplásticos/toxicidade , Polietileno/toxicidade , Transcriptoma/genética , Animais , Daphnia/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Dióxido de Silício/química , Testes de Toxicidade Crônica , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
10.
Aquat Toxicol ; 222: 105448, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32197184

RESUMO

Pyriproxyfen (PPF) is a synthetic substance and an insect juvenile hormone agonist with growth regulating effect. It is used worldwide as a pesticide in agriculture and public health campaigns, including the control of Aedes aegypti proliferation. It has low volatility, high Kow value and high lability in aerobic aquatic systems but is considered persistent in anaerobic systems, with a half-life of 288.9 days. The objective of this study is to survey the environmental contamination by pyriproxyfen in aquatic environmental matrices, to review the acute and chronic toxicity in non-target aquatic organisms and to make a risk assessment for the organisms addressed in the bibliographic survey. Pyriproxyfen quantification studies in aquatic environmental matrices are quite scarce and punctual-not representative of regional and global contamination. The water of the River Júcar (Spain) presented the highest concentration of PPF (99.59 ng L-1) among the matrices analysed, which is equivalent to 1% of the maximum dose allowed by the World Health Organization for use in drinking water. Acute and chronic aquatic toxicity studies with LC50, EC50, LOEC and NOEC values of PPF were compiled and interpreted to evaluate possible risks to non-target aquatic organisms. Pyriproxyfen caused a high risk at concentrations detected in aquatic environments for Daphnia magna, with probable reproductive effects and occasional survival risk. This species was the most sensitive to the pesticide, with the lowest estimated concentration of 50 % of effect values, followed by a freshwater fish (Xiphophorus maculatus) and estuarine crustaceans (Eurytemora affinis and Leander tenuicornis). The most resistant organisms to PPF within the endpoints addressed in this review were Danio rerio (zebrafish) and Capitella sp. (polychaete). Through the species sensitivity distribution (SSD), it was possible to estimate HC5 at 0.214 µg L-1 and that 2.3 % of the species present high sensitivity to pyriproxyfen in the environmental concentration detected in river water and 25.82 % of the species are affected in the concentration allowed for lavicidal use. In order to obtain more accurate risk estimates, we suggest ecotoxicological assessments in other species, covering various taxa, with emphasis on microcrustaceans due to their fundamental role in the aquatic food web and taxonomic proximity to pesticide target organisms. Furthermore, additional studies of contamination in aquatic environmental matrices are required, with particular attention to freshwater and estuarine environments due to the proximity to the sources of pyriproxyfen and environmental characteristics suggesting high accumulation. Thus, it will be possible to estimate realistic exposure levels and risks in different environments, contributing to effective and safe decision making, integrating development, public health and environmental policy.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Praguicidas/toxicidade , Piridinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ciprinodontiformes/crescimento & desenvolvimento , Daphnia/efeitos dos fármacos , Ecotoxicologia , Dose Letal Mediana , Nível de Efeito Adverso não Observado , Medição de Risco , Rios/química , Espanha , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Peixe-Zebra/crescimento & desenvolvimento
11.
Ecotoxicol Environ Saf ; 192: 110309, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061985

RESUMO

In this study, chronic toxicity of three endocrine disrupting chemicals (EDCs) used to make plastic products (i.e., bisphenol A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and nonylphenol (NP)) in a Korean resident fish (Cyprinus carpio), crustacean (Moina macrocopa) and green alga (Pseudokirchneriella subcapitata) species was tested. It was found that M. macrocopa was particularly sensitive to those EDCs, especially DEHP and NP. We exposed M. macrocopa to DEHP (0.0012-0.1 mg/L) and NP (0.00037-0.03 mg/L), and as a result, both chemicals significantly delayed the first day of reproduction. The no observed effect concentrations (NOECs) of DEHP and NP for this endpoint were determined to be 0.0012 and 0.00037 mg/L, respectively, which are far lower than NOECs for any other freshwater species. Existing water quality criteria of various governmental agencies do not consider the toxicity of those EDCs on M. macrocopa, and thus, use of the existing criteria for the risk assessment of the Korean freshwater environment may underestimate the ecological risk. This study recommends using the water quality criteria derived in this study (0.95 µg/L for DEHP and 0.16 µg/L for NP) based on the chronic toxicity data on Korean resident species including M. macrocopa for the aquatic ecological risk assessment in Korea rather than adopting the existing water quality criteria.


Assuntos
Disruptores Endócrinos/toxicidade , Plastificantes/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Compostos Benzidrílicos/toxicidade , Carpas , Clorófitas/efeitos dos fármacos , Cladocera/efeitos dos fármacos , Dietilexilftalato/toxicidade , Fenômenos Ecológicos e Ambientais , Fenóis/toxicidade , Reprodução/efeitos dos fármacos , República da Coreia , Medição de Risco , Testes de Toxicidade Crônica , Qualidade da Água
12.
Environ Toxicol Chem ; 39(1): 30-41, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31598995

RESUMO

No-observed-effect concentrations (NOECs) are used in environmental hazard classification and labeling of chemicals and their environmental risk assessment. They are typically obtained using standard tests such as the fish early-life stage (FELS) toxicity test, the chronic Daphnia reproduction test, and the algae growth inhibition test. Given the demand to replace and reduce animal tests, we explored the impact of the FELS toxicity test on the determination of effect concentrations by comparing the FELS toxicity test and the Daphnia and algae acute or chronic toxicity tests. Lowest-observed-effect concentrations (LOECs) were used instead of NOECs for better comparison with median lethal or effect concentration data. A database of FELS toxicity data for 223 compounds was established. Corresponding Daphnia and algae toxicity tests were identified using established databases (US Environmental Protection Agency ECOTOX, Organisation for Economic Co-operation and Development QSAR Toolbox, eChemPortal, EnviroTox, and OpenFoodTox). Approximately 9.5% of the investigated compounds showed a 10-fold higher sensitivity with the FELS toxicity test in comparison with the lowest effect concentrations obtained with any of the other tests. Some of these compounds have been known or considered as endocrine disrupting, or are other non-narcotic chemicals, indicating that the higher sensitivity in the FELS toxicity test is related to a specific mechanism of action. Targeting these mechanisms by alternative test systems or endpoints, using fish embryos for instance, may allow reduction or replacement of the FELS toxicity test or may allow us to prioritize compounds for conduction of the FELS toxicity test. Environ Toxicol Chem 2019;39:30-41. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Alternativas aos Testes com Animais , Clorófitas/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Peixes , Xenobióticos/toxicidade , Animais , Ecotoxicologia , Disruptores Endócrinos/toxicidade , Peixes/crescimento & desenvolvimento , Organização para a Cooperação e Desenvolvimento Econômico , Medição de Risco , Testes de Toxicidade Crônica , Estados Unidos , United States Environmental Protection Agency , Poluentes Químicos da Água/toxicidade
13.
Toxicol Appl Pharmacol ; 388: 114872, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881176

RESUMO

Acetamide (CAS 60-35-5) is detected in common foods. Chronic rodent bioassays led to its classification as a group 2B possible human carcinogen due to the induction of liver tumors in rats. We used a toxicogenomics approach in Wistar rats gavaged daily for 7 or 28 days at doses of 300 to 1500 mg/kg/day (mkd) to determine a point of departure (POD) and investigate its mode of action (MoA). Ki67 labeling was increased at doses ≥750 mkd up to 3.3-fold representing the most sensitive apical endpoint. Differential gene expression analysis by RNA-Seq identified 1110 and 1814 differentially expressed genes in male and female rats, respectively, following 28 days of treatment. Down-regulated genes were associated with lipid metabolism while up-regulated genes included cell signaling, immune response, and cell cycle functions. Benchmark dose (BMD) modeling of the Ki67 labeling index determined the BMD10 lower confidence limit (BMDL10) as 190 mkd. Transcriptional BMD modeling revealed excellent concordance between transcriptional POD and apical endpoints. Collectively, these results indicate that acetamide is most likely acting through a mitogenic MoA, though specific key initiating molecular events could not be elucidated. A POD value of 190 mkd determined for cell proliferation is suggested for risk assessment purposes.


Assuntos
Acetamidas/toxicidade , Carcinógenos/toxicidade , Contaminação de Alimentos , Neoplasias Hepáticas/genética , Modelos Biológicos , Animais , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imunidade/efeitos dos fármacos , Imunidade/genética , Antígeno Ki-67/análise , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Masculino , RNA-Seq , Ratos , Ratos Wistar , Medição de Risco/métodos , Testes de Toxicidade Crônica/métodos , Regulação para Cima/efeitos dos fármacos
14.
Bull Environ Contam Toxicol ; 103(6): 814-821, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606772

RESUMO

To understand the toxic mechanism of ammonia and identify effective biomarkers on the oxidative stress for the fish Carassius auratus red var., acute and chronic toxicity tests were conducted. The 96-h LC50 of total ammonia nitrogen (TAN) for C. auratus was 135.4 mg L-1, the corresponding unionized ammonia (NH3) concentration was 1.5 mg L-1. The activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione-peroxidase (GSH-Px) and glutathione (GSH) showed an increase with a subsequent falling, while the malondialdehyde (MDA) increased during the chronic test. The SOD, MDA, and GSH could be effective biomarkers to evaluate the TAN oxidative stress, the maximum acceptable toxicant concentration (MATC) was 11.3 mg L-1 for TAN. To our knowledge, this is the first study to propose biomarkers to evaluate potential environmental risk and establish a risk threshold for TAN in C. auratus.


Assuntos
Amônia/toxicidade , Aquicultura/métodos , Monitoramento Ambiental/métodos , Carpa Dourada/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , China , Relação Dose-Resposta a Droga , Carpa Dourada/metabolismo , Dose Letal Mediana , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Urbanização
15.
J Toxicol Environ Health A ; 82(18): 977-989, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31607230

RESUMO

Haloacetic acids (HAAs) are undesirable disinfection by-products (DBPs), released into aquatic ecosystems from various anthropogenic and natural sources. The aim of this study was to examine the ecological risk of exposure to three HAAs commonly detected in water, such as monobromoacetic acid (MBA), monochloroacetic acid (MCA), and trichloroacetic acid (TCA), in in vivo acute and chronic toxicity tests using Daphnia magna as a model. Acute tests showed that MBA was the most toxic of these compounds followed by MCA and TCA as evidenced by immobilization. Aquatic organisms in natural conditions might be exposed simultaneously to numerous compounds; thus, binary mixtures of selected HAAs and a ternary mixture of these were tested. Concentration addition (CA) and independent action (IA) models were used for a predictive assessment of mixture toxicity. Data demonstrated that CA appeared to be the most reliable indicator for HAAs binary and ternary mixtures suggestive of an additive behavior. Median effective concentration (EC50) values from the mixed exposure tests were significantly lower than results obtained from single tests for all three HAAs where an increase of toxicity greater than 50%. Multigenerational chronic tests were also performed exposing daphnids to the ternary mixture of HAAs. A markedly decreased sexual maturity and number of offspring and broods per daphnid especially in the second generation were noted.


Assuntos
Acetatos/toxicidade , Daphnia/efeitos dos fármacos , Monitoramento Ambiental/métodos , Medição de Risco/métodos , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade , Animais , Testes de Toxicidade Crônica
16.
Regul Toxicol Pharmacol ; 109: 104498, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31604110

RESUMO

Intensive discussions are ongoing about the interpretation of pulmonary effects observed in rats exposed to poorly soluble particles. Alveolar clearance differs between rats and humans and becomes impaired in rats at higher exposure concentrations. Some have doubted the human relevance of toxic effects observed in rats under impaired clearance conditions and have suggested that experimental exposures should stay below concentrations inducing impaired clearance. However, for regulatory purposes, insight in potential health effects at relatively high concentrations is needed to fully understand the hazard. Many aspects of impaired particle clearance remain unclear, hampering human health hazard and risk assessment. For an adequate evaluation of the impact of impaired clearance on pulmonary toxicity, a clear definition of alveolar clearance is needed that enables to quantitatively relate the level of impairment to the induction of adverse pulmonary health effects. Also, information is needed on the mechanism of action and the appropriate dose metric for the pulmonary effects observed. In absence of these data, human hazard and risk assessment can only be performed in a pragmatic way. Unless available data clearly point out otherwise, rat pulmonary toxicity including lung inflammation and tumour formation, needs to be considered relevant for human hazard and risk assessment.


Assuntos
Poluentes Atmosféricos/toxicidade , Exposição por Inalação/efeitos adversos , Lesão Pulmonar/induzido quimicamente , Medição de Risco/normas , Animais , Humanos , Lesão Pulmonar/diagnóstico , Nível de Efeito Adverso não Observado , Tamanho da Partícula , Material Particulado , Ratos , Medição de Risco/métodos , Especificidade da Espécie , Testes de Toxicidade Crônica/métodos , Testes de Toxicidade Crônica/normas , Testes de Toxicidade Subcrônica/métodos , Testes de Toxicidade Subcrônica/normas
17.
J Environ Sci Health B ; 54(8): 655-664, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31177923

RESUMO

Little is known about the effects of polluted water bodies from Buenos Aires Province on the development of native fauna. Ecotoxicological quality of water bodies from agricultural sites was evaluated by means of standardized laboratory bioassays with embryos and larvae of the native amphibian Rhinella arenarum. The organisms were acutely and chronically exposed to surface water samples from streams of Arrecifes (A), Pergamino (P) and Salto (S) districts that represent the most important agricultural core from the region. Lethal, sublethal and genotoxic effects were assessed. Water sample from (A) caused chronic toxicity (LC50:45.35%) in embryos, followed by (S) and the water sample from (P) was not toxic. In larvae, an inversion of the toxicity pattern was found. Thus, the 504 h-LC50s were 28.12%, 39% and 61% for (S), (P) and (A), respectively. A stage-dependent sensitivity was registered, being larvae more affected than embryos. Significant genotoxic effects, estimated by micronucleus test were observed in the larvae exposed to water samples from all sites. The present study warns about environmental degradation of surface waters next to agricultural areas of Buenos Aires Province. This fact jeopardizes R. arenarum populations in this area.


Assuntos
Bufo arenarum/embriologia , Ecotoxicologia/métodos , Qualidade da Água , Animais , Argentina , Bioensaio/normas , Ecotoxicologia/normas , Embrião não Mamífero , Larva/efeitos dos fármacos , Dose Letal Mediana , Testes para Micronúcleos , Rios , Testes de Toxicidade Crônica
18.
Ecotoxicol Environ Saf ; 180: 1-11, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31055079

RESUMO

There is a high demand for the development of reliable chronic toxicity tests using tropical marine species for subsequent use in tropical risk assessment. However, many chronic test endpoints can be laborious and time-consuming to assess, particularly if the endpoints require measurements of individuals (e.g. growth, size) or advanced taxonomic expertise (e.g. differentiating between larval development stages). In this study, we used scanning and image recognition (SIR) technology to develop and validate a chronic toxicity test with larvae of the tropical euryhaline copepod, Acartia sinjiensis. Optimisation steps are described, and included egg age, and effect of algal food type and salinity on toxicity. Comparisons were made between traditional endpoints measured using microscopy and those measured using SIR. Traditional endpoints of larval development ratio (LDR) and survival achieved using microscope examination and SIR were almost identical (R2 = 0.96-0.97). Additional endpoints made possible by SIR included larval development index (LDI; based on the number of animals at different stages of development), and a range of size measurements (e.g. surface area, perimeter and length) for individual animals and for total populations (i.e. a proxy for biomass). The SIR-derived endpoints were based on measurements that had concentration-dependant responses to tested toxicants (copper, nickel, ammonia), and were a sub-set of the full range of metrics provided by the software. Toxicity values based on SIR-measurements were similar to or more sensitive than the traditional LDR endpoint. SIR technology provides a major opportunity to improve and modernise larval development tests for a range for species, but comes at a cost of increased data size and complexity. Therefore, as a research tool, SIR has significant advantages over traditional microscope methods, but for routine toxicity testing, SIR incorporation into invertebrate toxicity testing will benefit from further improvements to the associated software and data management systems.


Assuntos
Automação , Copépodes/efeitos dos fármacos , Ecotoxicologia/métodos , Desenvolvimento Embrionário/efeitos dos fármacos , Larva/efeitos dos fármacos , Testes de Toxicidade Crônica/métodos , Animais , Austrália , Ecotoxicologia/instrumentação , Interpretação de Imagem Assistida por Computador , Larva/crescimento & desenvolvimento , Microscopia , Água do Mar/química , Software , Testes de Toxicidade Crônica/instrumentação , Poluentes Químicos da Água/toxicidade
19.
Food Funct ; 10(3): 1386-1397, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30747932

RESUMO

In this research, astaxanthin-rich nanopowder was prepared by nanoencapsulation and freeze-drying techniques with enhanced bioavailability and antioxidant activities. The nanopowder showed a maximum solubility of 230 mg mL-1 with an astaxanthin content as high as 2.9%. Compared with free astaxanthin, the astaxanthin-loaded nanopowder exhibited a more efficient antioxidant effect: an oral dose of 0.9 mg per kg BW significantly reduced the malondialdehyde and protein carbonyl contents, and increased the glutathione content as well as the superoxide dismutase activities in alcohol-induced acute hepatic injured mice, and maintained these oxidative stress indicators at a normal level for a longer period when treated with nanoencapsulated-astaxanthin than free astaxanthin. Simulated gastrointestinal tract studies demonstrated that the nanopowder with pH and DNase I-dependent dissociation properties delivered astaxanthin efficiently to the small intestine. Astaxanthin-rich nanopowder with a dose as high as 2.4 mg per kg BW (equivalent to astaxanthin) showed no chronic toxicity to mice in terms of hematology and pathological histology, indicating its impressive biocompatibility for biomedical applications. Pharmacokinetics and relative bioavailability (207%) of the nanopowder further proved that DNA/chitosan nanocarriers significantly improved the delivery efficiency of astaxanthin. With enhanced bioavailability and antioxidant activities, this novel type of astaxanthin-loaded nanopowder is expected to find broad application in the food and drug industry.


Assuntos
Antioxidantes/farmacologia , Antioxidantes/toxicidade , Nanopartículas/química , Água/química , Animais , Antioxidantes/química , Antioxidantes/farmacocinética , Disponibilidade Biológica , Masculino , Camundongos , Estresse Oxidativo , Distribuição Aleatória , Testes de Toxicidade Crônica , Xantofilas/química , Xantofilas/farmacocinética , Xantofilas/farmacologia , Xantofilas/toxicidade
20.
Niger J Physiol Sci ; 34(2): 215-221, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-32343273

RESUMO

Many pharmaceutical industries carelessly handle their effluents and indiscriminately release same to aquatic environment. These effluents often find their ways into surface and ground waters, contaminating public water and thus, serving as a potential threat to animals and human health. In this study, we investigated the cardiorenal effects of chronic oral exposure to pharmaceutical effluent in mice. Thirty male mice (Mus musculus) were randomly divided into groups A-F and treated with 0.2 mLs 0.0 %, 2.5 %, 5.0%, 10.0%, 20.0% and 40% concentration (v/v, effluent/distilled water) of the effluent for 28 days, respectively. At the end of the experiment, the animals were sacrificed by cervical dislocation. Activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were determined in serum and heart homogenate, while uric acid, creatinine and electrolytes (sodium, potassium, bicarbonate and chloride ions) were determined in serum only. Data were expressed as Means ± standard error of mean and values were considered significant at p < 0.05. Results showed that, oral exposure to pharmaceutical effluent reduced (p < 0.05) cardiac ALP, AST and ALT activities as well as serum ALT activity. However, serum activities of ALP, creatinine and uric acid were elevated (p < 0.05). Similarly, there was derangement of electrolytes (potassium, chloride, bicarbonate and sodium ions) in the exposed mice, compared with control. This study has demonstrated that poorly treated pharmaceutical effluent disrupted cardiac and serum enzyme activities, caused electrolytes imbalance and elevated serum uric acid level, suggesting that, drinking water contaminated with pharmaceutical effluent may impair kidney and cardiac functions. Further study, investigating the histology of the kidney and heart of the pharmaceutical effluent-exposed animals as well as mechanism(s) of cardiorenal toxicity of the effluent, should be carried out to exploit its roles in pathogenesis of cardiorenal diseases.


Assuntos
Coração/efeitos dos fármacos , Resíduos Industriais/efeitos adversos , Rim/efeitos dos fármacos , Animais , Indústria Farmacêutica , Masculino , Camundongos , Distribuição Aleatória , Testes de Toxicidade Crônica
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