%0 Journal Article
%T Evaluation of the efficiency of the sewage treatment plant from the University of Santa Cruz do Sul (UNISC), RS, Brazil Avalia  o da efici那ncia da esta  o de tratamento de esgoto da Universidade de Santa Cruz do Sul (UNISC), RS, Brasil
%A Adriana D邦pont
%A Eduardo Alcayaga Lobo
%J Acta Limnologica Brasiliensia
%D 2012
%I 
%X AIM: The main objective was to evaluate the efficiency of the sewage treatment plant (STP) of UNISC, through the ecotoxicological characterization and the analyses of the physical, chemical and microbiological variables from the raw and treated effluent. METHODS: Samples were collected during 2008 and 2009 for performing acute toxicity (Daphnia magna), chronic toxicity (Ceriodaphnia dubia), as well as the determination of environmental variables. RESULTS: The results indicated acute toxicity with an EC(I)50 48 hours average of 64.1 ㊣ 9.9%, characterized as moderately toxic, and an average chronic toxicity CI(I)25 of 8,1 ㊣ 2.6%, characterized as highly toxic. The total phosphorus (3.6 ㊣ 1.4 mg L-1) and the ammonia nitrogen (77.8 ㊣ 22.5 mg L-1) showed high concentration in the treated effluent, highlighting the STP inefficiency and, specially, the large amount of nutrients that the system is introducing into the receiving waterbody, the Lajeado Stream, condition that characterizes a large potential environmental impact known as eutrophication. The treated effluent showed high levels of thermotolerant coliforms, reaching an average of 6.4 ℅ 10(5) ㊣ 8.6 ℅ 10(5) NMP 100 mL-1, corresponding to a potential pollution load of high impact in the receiving waterbody, characterizing therefore a public health problem. CONCLUSIONS: The Lajeado Stream has no supporting capacity for preventing acute and chronic effects on biota. OBJETIVO: O principal objetivo foi avaliar a efici那ncia da esta  o de tratamento de efluentes (ETE) da UNISC, atrav谷s da caracteriza  o ecotoxicol車gica e de an芍lises das vari芍veis f赤sicas, qu赤micas e microbiol車gicas do efluente bruto e tratado. M谷TODOS: Amostras foram coletadas em 2008 e 2009, para a realiza  o de ensaios de toxicidade aguda (Daphnia magna) e toxicidade cr nica (Ceriodaphnia dubia), al谷m da determina  o de vari芍veis ambientais. RESULTADOS: Os resultados indicaram toxicidade aguda, com uma CE(I)50 48 horas m谷dia de 64,1 ㊣ 9,9%, caracterizada como medianamente t車xica, e uma toxicidade cr nica m谷dia CI(I)25 de 8,1 ㊣ 2,6%, caracterizada como extremamente t車xica. As vari芍veis f車sforo total (3,6 ㊣ 1,4 mg L-1) e nitrog那nio amoniacal (77,8 ㊣ 22,5 mg L-1), apresentaram altas concentra  es no efluente tratado demonstrando a inefici那ncia da ETE e, principalmente, o grande aporte de nutrientes que o sistema lan a ao corpo receptor, o Arroio Lajeado, condi  o que caracteriza um grande impacto ambiental potencial conhecido como eutrofiza  o. O efluente tratado apresentou 赤ndices elevados de coliformes termotolerantes, atingindo um valor m谷di
%K esta  o de tratamento de esgoto
%K qualidade do efluente tratado
%K Daphnia magna
%K Ceriodaphnia dubia
%K sewage treatment plant
%K quality of treated effluent
%K Daphnia magna
%K Ceriodaphnia dubia
%U http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2179-975X2012000200001