RESUMO
El hombre ha cambiado el ambiente para sostener la demanda global de recursos naturales como el agua. La gestión de los cuerpos hídricos tiene que ser constante, con el propósito preventivo y correctivo, dependiendo del estado de antropización de cada sistema. El objetivo de este artículo fue analizar la toxicidad del sedimento y los metales Mn, Zn, Pb, Ni, Cd y Cu, en el reservorio Paiva Castro, que abastece la Region Metropolitana de São Paulo. Se realizaron 2 muestreos (Mayo 2011, estación seca y Enero de 2012, estación húmeda) y se analizaron 5 puntos próximos a la captación de agua por la Companhia de Saneamento Básico do Estado de São Paulo. Se realizaron ensayos de toxicidad aguda y crónica en sedimento, a través de ensayos biológicos con el cladócero Daphnia similis y el insecto Chironomus xanthus. El tratamiento de datos se realizó con el test de Fisher (mortalidad). El nivel de asociación entre las variables en sedimento y en los test ecotoxicológicos fueron evaluados por test no-paramétricos, a través del coeficiente de correlación de Spearman's. Los resultados del presente trabajo señalaron bajas concentracones de metales en el sedimento del área de estudio y ausencia de toxicidad en los organismos ensayados. Se puede concluir que área estudiada del reservorio Paiva Castro se encuentra poco impactada por los metales, sin efectos directos sobre la calidad de vida los organismos bentónicos: D. similis y C. xanthus.
Man had changed the natural environment in an attempt trying to supply the global demand for resources. The management of the hydric bodies has to be constant, with preventive and corrective purpose, depending on the eutrophization state of each one. The objective of this article was to analyze the sediment toxicity and the metals Mn, Zn, Pb, Ni, Cd and Cu, in the Paiva Castro reservoir, that supply the Metropolitan Region of São Paulo. It was made 2 collections (May 2011, dry season and January 2012, wet season). It was analyzed 5 points next to the water captation station by the Companhia de Saneamento Básico do Estado de São Paulo. The sediment was analyzed as for acute and chronic toxicity through bioassays with the cladocerans Daphnia similis and the insect Chironomus xanthus. Data treatment was done with Fisher Exact Test (mortality). The association level between the variables in sediment and ecotoxicological tests was available in non-parametric tests, through the Spearman's correlation coefficient. Oriented on the results presented in this work, pointing low concentrations of heavy metals in the sediments presented in the collect local, and the absence of toxicity, we can say that at this reservoir, at least in the collect area, it's low impacted, not implicating in direct interferences in the quality of life of benthonic organisms.
Assuntos
Zinco/toxicidade , Cádmio/toxicidade , Reservatórios de Água/prevenção & controle , Sedimentos/análise , Cobre/toxicidade , Chumbo/toxicidade , Manganês/toxicidade , Níquel/toxicidade , Brasil , Metais Pesados/toxicidade , Testes de Toxicidade Aguda/análise , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/análise , Testes de Toxicidade Crônica/métodosRESUMO
Bisphenol A (BPA) is a plasticizer and a risk when it interacts with organisms, and can cause changes in the development and reproduction of them. This study aimed to evaluate the effects of BPA, by acute and chronic toxicity tests with neonates and adults of Pomacea lineata. Adults and neonates were divided into groups exposed to BPA (1-20mg/L), or 17ß-estradiol (1mg/L) and control in the acute and chronic toxicity tests. Behavior, heart rate, reproduction and hemolymph biochemical analysis were measured. In the acute toxicity test, the 96-h LC50 with adults was 11.09 and with neonates was 3.14mg/L. In this test, it was observed lethargic behavior and an increase of 77.6% of aspartate aminotransferase in the adults' hemolymph (p<0.05); and neonates' heart rate decreased 72.7% (p<0.05). In the chronic toxicity test, it was observed behaviors associated with reproduction, as Copulate, in the groups exposed to BPA. The results that were found in this study proved that BPA is a potentially toxic agent to Pomacea lineata according to biological parameters evaluated. These data contribute to the understanding of BPA toxic effects' in the aquatic invertebrates.
Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Gastrópodes/efeitos dos fármacos , Fenóis/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Fatores Etários , Animais , Aspartato Aminotransferases/metabolismo , Comportamento Animal/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemolinfa/efeitos dos fármacos , MasculinoRESUMO
The organophosphorus (OP) pesticide malathion is a neurotoxic compound whose acute toxicity is primarily caused by the inhibition of acetylcholinesterase (AChE), leading to cholinergic syndrome-related symptoms. Some lines of evidence indicate that long-term exposure to low levels of OP may produce neuropsychiatric and/or neurobehavioral signs that do not necessarily involve the AChE inhibition. This study evaluated the effects of a repeated (15-day period) and low-dose malathion exposure on spatial memory and discrimination (object location task), as well as on biochemical parameters in the hippocampus of mice [AChE and mitochondrial chain complexes activities; levels of proapoptotic proteins (Bax and Bak) and cholinergic neuronal and astroglial markers (ChAT and GFAP, respectively)]. Malathion treatments (30 and 100 mg/kg, s.c.) did not affect the body weight of animals and caused no evident signs of cholinergic toxicity throughout the treatment, although the highest dose (100 mg/kg) was associated with inhibition of AChE activity. Malathion-exposed animals showed a significant impairment on spatial memory and discrimination, which was correlated with a decrease in the mitochondrial complex I activity in the hippocampus. Moreover, malathion increased the levels of proapoptotic proteins and induced astroglial activation. The results show that long-term malathion exposure, at a dose that does not affect hippocampal AChE activity (30 mg/kg), caused impaired spatial memory and discrimination in mice that was related to hippocampal mitochondrial dysfunctional, astrogliosis and apoptosis. When extrapolated to humans, such results shed light on noncholinergic mechanisms likely related to the neurobehavioral and cognitive deficits observed in individuals chronically exposed to this pesticide.
Assuntos
Astrócitos/efeitos dos fármacos , Transtornos Cognitivos/induzido quimicamente , Hipocampo/efeitos dos fármacos , Inseticidas/toxicidade , Malation/toxicidade , Animais , Apoptose/efeitos dos fármacos , Astrócitos/patologia , Inibidores da Colinesterase/toxicidade , Relação Dose-Resposta a Droga , Hipocampo/patologia , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Memória Espacial/efeitos dos fármacos , Testes de Toxicidade Crônica/métodosRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Limonium brasiliense (Boiss.) Kuntze, Plumbaginaceae, popularly known as baicuru, has been used in folk medicine to treat menstrual cramps and to regulate menstrual periods. However, little is known about its safety. This study evaluated the safety through in vivo tests of the acute, long-term, and liver toxicity, and the mutagenicity of the crude extract (CE) from rhizomes of L. brasiliense. MATERIALS AND METHODS: The acute toxicity was assessed in Swiss mice, and the chronic toxicity in Wistar rats. Male and female mice received the CE orally in single doses of 1.0, 2.0, 3.0, 4.0, or 5.0 g/kg. Clinical changes and mortality rate were used as parameters to assess the acute toxicity. In the long-term evaluation, male and female Wistar rats were treated orally with daily doses of the CE (50, 100, or 200 mg/kg) for 90 days. Assessments of weight, behavior and food intake, urinalysis, biochemical and hematological analyses, as well as macro- and microscopic observations of several organs were performed. The redox state of the liver was evaluated as a means of investigating the liver toxicity, and the micronucleus test to assess mutagenicity was also performed. RESULTS: Evaluation of acute toxicity indicated no apparent clinical change in the animals; the LD50 was 4.8 g/kg. Evaluation after 90 days administration showed that the CE, even in higher doses than are considered therapeutic, appeared to be safe. The micronucleus test demonstrated a low mutagenic potential for the CE. CONCLUSION: Our results showed that treatment with the CE from L. brasiliense caused low or no toxicity, as assessed using these doses and evaluation methods.
Assuntos
Extratos Vegetais/toxicidade , Plumbaginaceae , Rizoma/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Masculino , Camundongos , Extratos Vegetais/isolamento & purificação , Ratos , Ratos WistarRESUMO
Occupational toxicology and clinical pharmacology integration will be useful to understand potential exposure-drug interaction and to shape risk assessment strategies in order to improve occupational health. The aim of the present study was to evaluate the effect of exposure to ethanol fuel on in vivo activities of cytochrome P450 (CYP) isoenzymes CYP3A, CYP2C and CYP2D by the oral administration of the probe drugs verapamil, ibuprofen and fluoxetine. Male Wistar rats exposed to filtered air or to 2000 ppm ethanol in a nose-only inhalation chamber during (6 h/day, 5 days/week, 6 weeks) received single oral doses of 10 mg/kg verapamil or 25 mg/kg ibuprofen or 10 mg/kg fluoxetine. The enantiomers of verapamil, norverapamil, ibuprofen and fluoxetine in plasma were analyzed by LC-MS/MS. The area under the curve plasma concentration versus time extrapolated to infinity (AUC(0-∞)) was calculated using the Gauss-Laguerre quadrature. Inhalation exposure to ethanol reduces the AUC of both verapamil (approximately 2.7 fold) and norverapamil enantiomers (>2.5 fold), reduces the AUC(0-∞) of (+)-(S)-IBU (approximately 2 fold) and inhibits preferentially the metabolism of (-)-(R)-FLU. In conclusion, inhalation exposure of ethanol at a concentration of 2 TLV-STEL (6 h/day for 6 weeks) induces CYP3A and CYP2C but inhibits CYP2D in rats.
Assuntos
Biocombustíveis/toxicidade , Indutores das Enzimas do Citocromo P-450/toxicidade , Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Etanol/toxicidade , Exposição por Inalação/efeitos adversos , Testes de Toxicidade Crônica/métodos , Poluentes Ocupacionais do Ar/toxicidade , Animais , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Hidrocarboneto de Aril Hidroxilases/metabolismo , Câmaras de Exposição Atmosférica , Biomarcadores/sangue , Biotransformação/efeitos dos fármacos , Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/sangue , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Sistema Enzimático do Citocromo P-450/química , Indução Enzimática/efeitos dos fármacos , Fluoxetina/sangue , Fluoxetina/farmacocinética , Ibuprofeno/sangue , Ibuprofeno/farmacocinética , Limoneno Hidroxilases/antagonistas & inibidores , Limoneno Hidroxilases/metabolismo , Masculino , Ratos Wistar , Verapamil/análogos & derivados , Verapamil/sangue , Verapamil/química , Verapamil/farmacocinéticaRESUMO
In this study, the acute and chronic toxicity of the metals chromium and cadmium were tested against the tropical freshwater cladoceran Pseudosida ramosa. Acute tests showed that the 48-h LC50 of chromium was 29 µg L(-1) , while that of cadmium was 12 µg L(-1) . P. ramosa had a similar sensitivity to those of other cladoceran species cultured in the same conditions as in this study, or a higher sensitivity when water hardness was raised. Long-term chronic exposure of P. ramosa to chromium decreased maternal survival, fecundity, and fertility at a concentration of 10 µg L(-1) . For cadmium, reductions in the same endpoints were observed at a concentration of 3 µg L(-1) . Moreover, the degree of toxicity of the chromium and cadmium to P. ramosa after release of the first brood was similar to the result obtained after 21 days, using reproduction as the endpoint. Brazilian water bodies located near industrial areas already show concentrations of chromium and cadmium higher than levels causing acute and chronic toxicity to P. ramosa in our study. Many water quality criteria in tropical regions are based on ecotoxicological tests with non-native species and, consequently, this may lead to errors of interpretation when the permitted maximum levels of for each toxic substance are established. Therefore, we reinforce the idea of using native species to establish the maximum concentrations of toxic substances in water quality criteria, especially for metals, since their effects are related to water hardness, pH, and temperature specific to each region.
Assuntos
Cádmio/toxicidade , Cromo/toxicidade , Cladocera/efeitos dos fármacos , Ecotoxicologia/métodos , Poluentes Químicos da Água/toxicidade , Animais , Feminino , Fertilidade/efeitos dos fármacos , Dose Letal Mediana , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodosRESUMO
En nuestro país existe una gran extensión de hectáreas cultivadas con soja transgénica, la misma ha sido modificada genéticamente para soportar la acción de un herbicida denominado glifosato. Debido a la gran cantidad de formulaciones comerciales que incluyen glifosato es de importancia analizar el impacto ambiental producido por éstas. La evaluacion de la toxicidad aguda de dos herbicidas comerciales formulados con glifosato y de una solución del mismo; frente a peces de la especie Poecilia reticulata "lebistes" acusa que una de las soluciones produce mortalidad del 100 % de los especimenes a 100 μl/l (equivalente a 48 mg/l de principio activo); la otra a 50 μl/l (equivalente a 24 mg/l de principio activo) y la solución formulada con glifosato puro no produce mortalidad aún a concentraciones de 400 mg/l. Utilizando dosis sub letales en función de los datos obtenidos en el ensayo de toxicidad aguda se determinó que a largo plazo especimenes de Cyprinus carpio haematopterus "carpa koi", manifestaron severas alteraciones hematológicas principalmente frente a una de las formulaciones evaluadas.
Nowadays, transgenic soya, modified in order to withstand the impact of the herbicide glyphosate, in one of the main crops grown in Argentina. Due to the large number of commercial formulations that include this drug, is important to analyze both, the acute and chronic environmental impact that they cause. Here the acute toxicity of two commercial herbicides glyphosatebased toward the fish Poecilia reticulate "guppy" was evaluated and compared with pure glyphosate solutions. Interestingly, while commercial herbicides formulations induce a 100% of mortality at concentration ranged between 50 and 100 μl/l, the pure glyphosathe does not present mortality even at doses higher than 400 mg/l. When some long term effects toward Cyprinus carpio haematopterus "koi" were determined by using the sub-lethal doses already calculated it was demonstrated that one of the commercial herbicides induces severe haematological alterations.
Assuntos
Animais , Compostos Organofosforados/toxicidade , Agroquímicos/toxicidade , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Herbicidas/toxicidade , Poecilia , Carpas , Agroquímicos/efeitos adversos , Herbicidas/análiseRESUMO
As part of an experimental project on the treatment of bleach plant effluents the results of biodegradability and toxicity assessment of effluents from a bench-scale horizontal anaerobic immobilized bioreactor (HAIB) are discussed in this paper. The biodegradability of the bleach plant effluents from a Kraft pulp mill treated in the HAIB was evaluated using the modified Zahn-Wellens test. The inoculum came from a pulp mill wastewater treatment plant and the dissolved organic carbon (DOC) was used as the indicator of organic matter removal. The acute and chronic toxicity removal during the anaerobic treatment was estimated using Daphnia similis and Ceriodaphnia silvestrii respectively. Moreover, the evaluation of chromosome aberrations (CA), micronucleus frequencies (MN) and mitotic index (IM) in Allium cepa cells were used as genotoxicity indicators. The results indicate that the effluents from the anaerobic reactor are amenable to aerobic polishing. Acute and chronic toxicity were reduced by 90 and 81%, respectively. The largest CA and MN incidence in the meristematic cells of A. cepa were observed after exposure to the raw bleach plant effluent. The HAIB was able to reduce the acute and chronic toxicity as well as chromosome aberrations and the occurrence of micronucleus.
Assuntos
Anaerobiose , Reatores Biológicos/microbiologia , Clareadores , Hidrocarbonetos Clorados , Poluentes Químicos da Água , Purificação da Água/métodos , Aerobiose , Animais , Biodegradação Ambiental , Clareadores/análise , Clareadores/toxicidade , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Cebolas/efeitos dos fármacos , Cebolas/genética , Cebolas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/crescimento & desenvolvimento , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Purificação da Água/instrumentaçãoRESUMO
Mikania laevigata, popularly known in Brazil as "guaco", is largely used in folk medicine against respiratory diseases. However, neither the assessment of the toxicity of "guaco" syrup (GS, used by humans) nor its efficacy or mechanisms of action has been properly investigated. Using in vitro procedures, we showed that the hydroalcoholic extract (HE) from Mikania laevigata induces a concentration-dependent relaxation of rat trachea which does not depend on epithelium-derived substances but involves changes in the cellular mobilization of calcium, perhaps due to a direct effect on membrane potassium channels. In addition, we assessed both oral and intraperitoneal acute toxicity, as well as the oral subchronic and chronic toxicity of GS containing controlled amounts of coumarin, the main biological marker of Mikania laevigata preparations used in humans. The calculated LD(50) of GS after intraperitoneal administration was 0.904 g/kg in mice (both sexes) and 0.967 and 0.548 g/kg in male and female rats, respectively. However, the LD(50) values of GS by the oral route were calculated to be up to 10 g/kg, in both male and female mice and rats. Repeated dose 28- or 90-day oral treatment with GS (75, 150 and 300 mg/kg) did not produce any disturbances in the hematological or biochemical parameters of either male or female rats, nor did it provide evidence of toxicity in the hepatic, renal or pancreatic systems. Besides the mechanistic findings, our results provide evidence of the safety of Mikania laevigata in rodents, even after subchronic and chronic administration, at least in relation to the evaluated parameters.
Assuntos
Mikania/química , Relaxamento Muscular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Traqueia/efeitos dos fármacos , 4-Aminopiridina/farmacologia , Acetilcolina/farmacologia , Animais , Brasil , Cumarínicos/química , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glibureto/farmacologia , Técnicas In Vitro , Masculino , Camundongos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , NG-Nitroarginina Metil Éster/farmacologia , Oxidiazóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Bloqueadores dos Canais de Potássio/farmacologia , Quinoxalinas/farmacologia , Ratos , Ratos Wistar , Tetraetilamônio/farmacologia , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos , Traqueia/fisiologiaRESUMO
Dimorphandra mollis Benth. (Caesalpiniaceae), known as "faveira" or "fava d'anta" is a common plant in central Brazilian cerrado that is used mainly as a vasoprotector. Its main marker is rutin. The present study aimed to evaluate the security of Dimorphandra mollis dry extract in rodents. The extract presented a rutin content of 76+/-3%. Acute and chronic (180 days) toxicity was evaluated after per os administration. In acute toxicity, 3500 and 5000 mg/kg doses presented reversible effects. In chronic toxicity, 1000 and 2000 mg/kg doses did not provoke significant changes in body weight of the animals and in water and food consumption. Behavioral reversible changes and in blood count parameters (hemoglobin, hematocrit and red cells decrease and platelets increase in male in rats) were observed only in 2000 mg/kg dose. In biochemical evaluation, the results varied a lot considering doses and sex, without a linear profile. Some parameters showed a significant difference but without a clinical correlation. In histopathological examination, lung hemorrhage was observed in 2000 mg/kg dose. In conclusion, the study suggest that the extract is safe in a 1000 mg/kg dose, whereas for 2000 mg/kg dose further studies are needed. In long-term use, caution is required.