Ecotoxicology of Nano-TiO2 An Evaluation of its Toxicity to Organisms of Aquatic Ecosystems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Stability and Local Toxicity Evaluation of a Liposomal Prilocaine Formulation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pharmacological and local toxicity studies of a liposomal formulation for the novel local anaesthetic ropivacaine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of a Brazilian sewage outfall on the toxicity and contamination of adjacent sediments

The submarine sewage outfall of Santos (SSOS) is situated in the Santos Bay (São Paulo, Brazil) and is potentially a significant source of contaminants to the adjacent marine ecosystem. The present study aimed to assess the influence of SSOS on the sediment toxicity and contamination at Santos Bay. At the disposal site, sediments tended to be finer, organically richer and exhibited higher levels of surfactants and metals, sometimes exceeding the Threshold Effect Level values. The SSOS influence was more evident toward the East, where the sediments exhibited higher levels of TOC, total S and metals during the summer 2000 sampling campaign. Sediment toxicity to amphipods was consistently detected in four of the five stations studied. Amphipod survival tended to correlate negatively to Hg, total N and % mud. This work provides evidence that the SSOS discharge affects the quality of sediments from Santos Bay, and that control procedures are warranted. (c) 2005 Elsevier Ltd. All rights reserved.

Comparative toxicity of antifouling compounds on the development of sea urchin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sediment toxicity assessment of Guanabara Bay, Rio de Janeiro, Brazil.

Guanabara Bay (GB) comprises of estuarine and marine environments of high ecological and socio-economic relevance, together with port, industrial and urban areas. The anthropogenic activities produce environmental impacts, including the aquatic pollution. The sediment quality assessment is important to evaluate the effects of contamination, once sediments are a repository for most of the contaminants. In this Study, the quality of sediments from GB was evaluated, in rainy and dry periods, throughout the employment of acute toxicity tests with the amphipod Tiburonella viscana, and chronic bioassays with embryos of the sea-urchin Lytechinus variegatus. In the dry period, acute toxicity was found in the sediments from stations 1, 2 3 (NW) and 7 (near Guapimirim Environmental Protection Area). The bioassays with liquid phases showed effects, but were strongly influenced by the unionized ammonia levels, which were high in this period. In the rainy period, acute toxicity was found in sediments samples from stations 1, 2, 3, 6, 8, 10, 11, 12 and 15. Chronic toxicity could be clearly detected, as ammonia concentrations tended to be low in the most part of the samples. The results showed that the sediment toxicity is influenced by precipitation rates, which increase the input of contaminants to the Bay, and also allowed subdividing GB in three main zones: northwest (stations 1, 2, 3, 5), northeast (stations 6, 7, 8, 9) and centre-south (stations 10, 11, 12, 13, 14, 15). Results also showed that the quality of GB sediments is poor, and that toxicity tests could determine the combined effects of pollutants.

Acute and chronic toxicity of sediment samples from Guanabara Bay (RJ) during the rainy period

A Baía de Guanabara é um ambiente marinho-estuarino de grande relevância ecológica e sócio-econômica, e sujeita a uma ampla gama de impactos ambientais. O sedimento é o principal destino para a maioria das substâncias introduzidas nos corpos d'água, podendo fornecer uma medida integrada da qualidade ambiental, a qual pode ser avaliada por várias abordagens. Neste projeto, a qualidade de sedimentos da Baía de Guanabara foi por uma abordagem ecotoxicológica, por meio de testes de toxicidade aguda de sedimento integral, utilizando Tiburonella viscana, e testes de toxicidade crônica de água intersticial, elutriato e interface sedimento-água, utilizando embriões de Lytechinus variegatus. Os sedimentos foram coletados em 14 estações de amostragem. Nos testes crônicos houve efeitos significativos na maioria das amostras, enquanto os sedimentos coletados nas estações 1, 2, 3, 6, 8, 10, 11, 12 e 15 apresentaram também toxicidade aguda. Houve grande concordância entre os resultados dos diferentes testes, e sua integração mostrou que os sedimentos analisados encontram-se inadequados à vida aquática, indicando degradação ambiental na baía da Guanabara. Nesse contexto, o controle das fontes poluidoras e o gerenciamento dos múltiplos usos da baía devem ser implementados, no sentido da melhora da qualidade ambiental.

ACUTE TOXICITY of SODIUM SELENITE and SODIUM SELENATE TO TILAPIA, Oreochromis niloticus, FINGERLINGS

Selenium is an essential nutrient for many organisms, including fish. It can be released in the water by natural processes of dissolving rocks and minerals, and by the wastewater from industries and agricultural activities, which can increase its concentration in the environment, leading to toxic effects to the aquatic biota. Median Lethal Concentrations (LC(50-96h)) of two forms of selenium were estimated to fingerlings of Nile tilapia Oreochromis niloticus, focusing on estimating indicators for future environmental risk assessments in aquatic ecosystems contaminated with those elements, particularly for evaluate sources of water quality suitable for rearing tilapia. The results were: LC(50-96h) of sodium selenite (Na(2)SeO(3)) = 4.42 mg Se(4+) L(-1), and LC(50-96h) of sodium selenate (Na(2)SeO(4)) = 14,67 mg Se(6+) L(-1). According to those data, it was possible to classify sodium selenite as highly toxic and sodium selenate as moderately toxic to fingerlings of tilapia.

Toxicity of the therapeutic potassium permanganate to tilapia Oreochromis niloticus and to non-target organisms Ceriodaphnia dubia (microcrustacean cladocera) and Pseudokirchneriella subcapitata (green microalgae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Glyphosate has low toxicity to citrus plants growing in the field

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Larvicidal activity of the water extract of Moringa oleifera seeds against Aedes aegypti and its toxicity upon laboratory animals

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

ACUTE TOXICITY and ENVIRONMENTAL RISK of OXYTETRACYLINE and FLORFENICOL ANTIBIOTICS TO PACU (Piaractus mesopotamicus)

The oxytetracyline (OTC) and florfenicol (FLO) are the most used antibiotics for bacterial disease control in fish. The aims are: estimating the lethal concentration 50% initial (LC(I) 50;48h) of OTC (Terramicina (R)) and FLO (Aquaflor (R)) for pacu (Piaractus mesopotamicus); classifying OTC and FLO according to the acute toxicity and the risk of environmental intoxication; and assessing OTC and FLO dilution effect in water quality variables. Fish were acclimatized for 10 days in a bioassay room at 27 +/- 2 degrees C. Then nine animals (three each concentration) were exposed to 7.0; 7.5; 8.0 or 8.5 mg L(-1) of OTC or to 600.0; 700.0; 800.0; 900.0 and 1000.0 mg L(-1) of FLO and a control treatment. The water quality variables recorded daily were: pH, temperature, electric conductivity, and dissolved oxygen. OTC and FLO were classified according to acute toxicity and environmental risk. The estimated OTC LC(I) 50;48h for pacu is 7.6 mg L(-1) and the estimated FLO is > 1000 mg L(-1). OTC reduced the dissolved oxygen concentration, and it was considered moderately toxic, causing risk of environmental intoxication to pacu. FLO is not toxic; it does not cause risk of environmental intoxication to pacu and does not change water quality variables.

Detached leaf culture: Viability to evaluate 2,4-D toxicity symptoms in cotton apex leaves

To study the viability of detached leaf culture technique, studies were carried out with detached leaves from cotton apex (true trilobed leaves). The prepared leaves were sprayed with 2,4-D amine and ester, at rates of 10, 30, 70, and 100% of the recommended doses. Detached leaves without herbicide spray were used as controls. Simultaneously, a greenhouse experiment was conducted with the same treatments as used for the detached leaves experiment. Toxicity was measured through a 0-to-5 grading according to the percentage of affected leaf area in the detached leaves experiment or examining the affected rate of whole plant as indicated in the greenhouse. Results showed that the ester form of the herbicide induced earlier and more severe toxicity symptoms in detached leaves and greenhouse grown plants. Positive and significant correlations (p < 0.001) were found between toxicity results obtained at 7 and 14 days after application in detached leaves and greenhouse plants (r = 0.97 and 0.92, respectively). Negative, significant correlations (p < 0.005) were found between the toxicity levels found at 7 and 14 days after application in detached leaves and dry matter of cotton plants grown in the greenhouse (r = -0.92 and -0.92, respectively).

Effects and toxicity of Eugenia punicifolia extracts in streptozotocin-diabetic rats

Extracts and decoctions of Eugenia jambolana Lam., Eugenia uniflora L., and Eugenia punicifolia (Humb., Bonpl. & Kunt) DC. are used in traditional medicine to treat diabetes mellitus. Although there have been reports that Eugenia jambolana and Eugenia uniflora have antidiabetic effects, no study has yet been made on Eugenia punicifolia . We investigated the effects of aqueous, butanol, and methanol extracts of Eugenia punicifolia leaves administered by gavage to streptozotocin-diabetic rats for 26 to 29 days. Body weight, food and fluid intake, urine volume, and urinary glucose and urea were evaluated every 7 days. At the end of the experiment, we measured serum cholesterol, high-density lipoprotein (HDL)-cholesterol, triglycerides and bilirubin, hepatic glycogen and serum marker-enzymes (alanine and aspartate aminotransferases, alkaline phosphatase, gamma-glutamyltransferase, L-lactate dehydrogenase, creatine kinase, alpha-amylase, and angiotensin I converting enzyme). We found that in rats treated with the aqueous extracts, food and liquid intake, urinary volume, and body weight were all reduced, while for rats treated with the methanol extract, not only were liquid intake, urinary volume and body weight reduced, but urinary glucose and urea also decreased. Rats treated with the butanol extract showed no significant alterations in any of the parameters measured. Chronic treatment with extracts had no effect on the marker enzymes nor on serum bilirubin levels. The results indicate that aqueous extracts of Eugenia punicifolia leaves produced an anorexic effect and that methanol extracts had a beneficial effect on the diabetic state by improving carbohydrate and protein metabolism without provoking hepatobiliary, microvascular, muscular, or pancreatic toxic effects.

Acute, subacute toxicity and genotoxic effect of a hydroethanolic extract of the cashew (Anacardium occidentale L.)

Anacardium occidentale L. (Anacardiaceae), popularly known as cajueiro is a native plant to Brazil, and largely used in popular medicine to treat ulcers, hypertension and diarrhea. In the present study, acute, 30-day subacute toxicity and genotoxicity assays were carried out. The crude extract did not produce toxic symptoms in rats in doses up to 2000 mg/kg. Based on biochemical analyses of renal and hepato-biliary functions, such as the level of urea, creatinine, transaminases and alkaline phosphatase, we determined that the extract is generally tolerated by rats. This was also confirmed by hematological and histopathological exams. Genotoxicity was accessed by the Ames test in Salmonella typhimurium strains TA97, TA98, TA 100, TA 102 and by the bone marrow micronucleus test in mice. The extract was shown to induce frameshift, base pair substitution and damage to the chromosomes. However, this effect was less deleterious than the clastogenic effect of ciclophosphamide. (c) 2006 Elsevier B.V.. All rights reserved.