Subchronic Toxicity Evaluation of a Treated Urban Sewage Sludge

Disposal of tons of sludge produced daily by sewage treatment plants in large cities is a serious problem. Because recycling and application in agriculture have been proposed, the Brazilian National Environmental Council (CONAMA, 2006) issued a legal norm that regulates the use of the sewage sludge (SS) in crops. Due to the complex chemical nature of such products, characterization by analytical methods for health and environmental risk assessment has severe limitations. To overcome such limitations, it is necessary to (1) assess the toxicological potential of SS and (2) identify possible adverse effects in vivo in order to provide critical information for future environmental regulations. The present study was conducted to determine the potential toxicity of SS obtained from a representative urban treatment plant located in the São Paulo State, Brazil. Male and female Wistar rats were fed ad libitum a pelleted diet containing varying amounts of SS. No relevant clinical, hematological, urinary, or gross organ morphological alterations were observed in both genders of rats orally exposed to SS at up to 3.8 g/kg/d for 90 d. Sewage slude produced increased incidence of centrilobular hepatocyte hyperplasia at the high dose and significantly increased aspartate aminotransferease (AST) activities at all doses in both genders. Although the present data indicate some liver involvement, these alterations were considered adaptative and not toxicologically relevant, as the responses were relatively mild, not dose dependent, and no other parameters were markedly affected. The present results may contribute to the establishment of protocols for potential usage in SS agricultural soil application.

In vivo genotoxicity evaluation of a treated urban sewage sludge sample

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

Sewage sludge toxicity in edaphic organism: Analysis of midgut responses in the diplopod Rhinocricus padbergi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessment of the Toxic Potential of Sewage Sludge in the Midgut of the Diplopod Rhinocricus padbergi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização de lodo gerado em estações de tratamento de água: perspectivas de aplicação agrícola

The work reported here involved the characterization of sludges produced at water treatment plants in Jaboticabal-SP using FeCl3 as flocculant, and in Taquaritinga-SP and Manaus-AM using Al2(SO4)3 as flocculant. An evaluation was also made of the interaction of organic matter extracted from the sludges with different metal species. The results indicated that all the sludges produced at water treatment plants have an important agricultural potential and that their use depends on the characteristics of the raw water and the type of flocculant employed in conventional treatment. The humic substances extracted from the sludges showed different affinities for metal species, favoring eventual exchanges between potentially toxic metals and macro- and micronutrients. An alternative for the use of sludge in agriculture is to pretreat it to remove potentially toxic metals and enrich it with micro- and macronutrients that can be released to the plant.

Sugarcane grown in an oxisol amended with sewage sludge and vinasse: nitrogen contents in soil and plant

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Some reflections on the future of the water quality of the corumbataí River basin, São Paulo state, Brazil

The waters of Corumbataí River in the middle and eastern part of São Paulo State, Brazil, are extensively used for human consumption; their water quality has been modified mainly due to increasing pressure caused by population growth, accompanied by a more accentuated industrial development for the whole São Paulo State in the early 1970s. The Corumbataí River basin has, over time, received significant emissions of municipal waste products and discharges of wastewater, sludge, sewage, sanitary and industrial effluents, but the first effluent treatment plant at Rio Claro city was only inaugurated at the end of the 1990s. Data on river water quality from two widely spaced locations in the Corumbataí River basin are reported in this paper; they indicate the need for continuous initiatives and efforts by decision makers in order to improve and preserve the water quality in the basin for the 21st century. Copyright © 2007 IAHS Press.

Alterations in the fat body cells of rhinocricus padbergi (Diplopoda) resulting from exposure to substrate containing sewage sludge

Abstract The final disposal of residues generated at sewage treatment plants (STPs) has become a major problem for cities, due to the increase in the amount of treated sewage. One of the alternatives for the residue, labeled sewage sludge, is its reuse in agriculture and in degraded soil. However, not all pathogens and metals present in it are eliminated during treatment. Diplopods have been used as bioindicators in ecotoxicological tests as they are constantly in close contact with the soil. Owing to this fact, the purpose of this study was to expose specimens of the diplopod Rhinocricus padbergi to substrate containing sewage sludge collected at STPs to analyze morphological alterations in their parietal and perivisceral fat body, where substances are stored. The exposures were held for 7, 15, or 90 days at different concentrations of sewage sludge (control, 1%, 10%, and 50%). The parietal fat body showed no alterations in any of the three exposure periods or concentrations. Alterations in the perivisceral fat body were observed for all exposure periods. According to the results, we suggest that the sludge used has toxic agents responsible for changing the animal's perivisceral fat body. © 2012 Microscopy Society of America.

Development of a burner to measure biogas generation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Contaminação das águas por resíduos de medicamentos: Ênfase ao cloridrato de fluoxetina

The objective of this paper was to review data on residues of medical products in aquatic environments and at wastewater treatment plants. Secondarily the paper presents a discussion about the need for a good management of drugs residues and effluents generated by this sector. Bringing the evidences of environmental possible damages reported by ecotoxicity data on the effects of fluoxetine to Vibrio fischeri and H. azteca, aquatic organisms daily exposed to environmental contaminants. From the results we observed that 0.3 mg.l-1 of fluoxetine hidrochloride induced lethality to H. azteca and 30 mg.l-1 reduced the luminescence of Vibrio fischeri. This assay evidenced higher toxicity when we used the generic product.

Assessment of the genotoxicity of two agricultural residues after processing by diplopods using the Allium cepa assay

Agroindustrial by-products and residues from treatment of sewage sludge have been recently recycled as soil amendments. This study was aimed at assessing toxic potential of biosolid, obtained from a sewage treatment plant (STP), vinasse, a by-product of the sugar cane industry, and a combination of both residues using Allium cepa assay. Bioprocessing of these samples by a terrestrial invertebrate (diplopod Rhinocricus padbergi) was also examined. Bioassay assembly followed standards of the Brazilian legislation for disposal of these residues. After adding residues, 20 diplopods were placed in each terrarium, where they remained for 30 days. Chemical analysis and the A. cepa assay were conducted before and after bioprocessing by diplopods. At the end of the bioassay, there was a decrease in arsenic and mercury. For the remaining metals, accumulation and/or bioavailability varied in all samples but suggested bioprocessing by animals. The A. cepa test revealed genotoxic effects characterized by different chromosome aberrations. Micronuclei and chromosome breaks on meristematic cells and F1 cells with micronuclei were examined to assess mutagenicity of samples. After 30 days, the genotoxic effects were significantly reduced in the soil + biosolid and soil + biosolid + vinasse groups as well as the mutagenic effects in the soil + biosolid + vinasse group. Similar to vermicomposting, bioprocessing of residues by diplopods can be a feasible alternative and used prior to application in crops to improve degraded soils and/or city dumps. Based on our findings, further studies are needed to adequately dispose of these residues in the environment. © 2013 Springer Science+Business Media Dordrecht.

Caracterização morfofisiológica dos hemócitos do Diplópodo Rhinocricus padbergi antes e após exposição a substrato contendo lodo de esgoto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do método respirométrico pelo acompanhamento e controle de processo de compostagem de lodo de esgoto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desempenho de reator anaeróbio de fluxo ascendente alimentado com lodo de estação de tratamento de água e esgoto sanitário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização e biodegradação de lodo de estações de tratamento de água para descarte em aterro sanitário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)