Evaluation of sewage sludge effects, before and after biodegradation by microorganisms, using of toxicity, cytotoxicity, genotoxicity and mutagenicity bioindicators.

• Grant number: 09/09665-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: January 01, 2010
• End date: September 30, 2013
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Carmem Silvia Fontanetti Christofoletti
• Grantee: Dânia Elisa Christofoletti Mazzeo Morales
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

Poor management of human activities has caused serious impacts to ecosystems, thus affecting their quality and maintenance of environmental conditions. One problem that has been dogged in recent decades is the final disposal of waste generated in the sewage treatment process, particularly sewage sludge, which may contain toxic substances like heavy metals and organic substances, as well as pathogenic microorganisms. A viable alternative for the allocation of sewage sludge is its application in agriculture as soil reconditioning. However, accumulation of heavy metals in soils with sewage sludge may cause harmful effects to the associated biota and to human health. Another factor to be considered is the possible leaching of toxic substances into groundwater and the river systems around the sludge disposal area. The use of microorganisms in the biodegradation process seems to be a promising approach to reducing the toxicity of sewage sludge. To better assess the potential toxicity of sewage sludge, different tests using different bioindicators should be carried out. The aim of this project is to analyze the toxic, cytotoxic, genotoxic and mutagenic potential of sewage sludge, before and after the process of biodegradation by microorganisms, using test systems like Salmonella typhimurium, Allium cepa, Eisenia fetida and mammalian culture cells. The sewage sludge to be assessed will be collected at the Sewage Treatment Station of Rio Claro - SP. The tested samples will correspond to raw sludge (100%) and soil / sludge mixtures at proportions of 10% and 50% of mud for E. fetida and A. cepa. Assays with S. typhimurium, A. cepa and mammalian culture cell will be performed with the solubilized raw sludge and different soil / mud solubilized mixtures. Samples of sludge submitted to biodegradation for 2, 6 and 12 months will also be evaluated using the same tests to verify the effectiveness of biodegradation by microrganisms in the decomposition of toxic substances in sludge sewage.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHRISTOFOLETTI MAZZEO, DANIA ELISA; CASIMIRO FERNANDES, THAIS CRISTINA; LEVY, CARLOS EMILIO; FONTANETTI, CARMEM SILVIA; MARIN-MORALES, MARIA APARECIDA. Monitoring the natural attenuation of a sewage sludge toxicity using the Allium cepa test. ECOLOGICAL INDICATORS, v. 56, p. 60-69, SEP 2015. (09/09665-0)

CHRISTOFOLETTI MAZZEO, DANIA ELISA; CASADO, MARTA; PINA, BENJAMIN; MARIN-MORALES, MARIA APARECIDA. Detoxification of sewage sludge by natural attenuation and implications for its use as a fertilizer on agricultural soils. Science of The Total Environment, v. 572, p. 978-985, DEC 1 2016. (09/09665-0)

CHRISTOFOLETTI MAZZEO, DANIA ELISA; CASIMIRO FERNANDES, THAIS CRISTINA; MARIN-MORALES, MARIA APARECIDA. Attesting the efficiency of monitored natural attenuation in the detoxification of sewage sludge by means of genotoxic and mutagenic bioassays. Chemosphere, v. 163, p. 508-515, NOV 2016. (09/09665-0)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MORALES, Dânia Elisa Christofoletti Mazzeo. Avaliação da viabilidade do lodo de esgosto como recondicionante de solos agrícolas, após processo de atenuação natural, por meio de diferentes bioensaios. 2013. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Instituto de Biociências. Rio Claro Rio Claro.