Dinamic of pathogenic protozoa and cyanobacteria in a reservoir used for water supply in southeastern Brazil

O presente estudo foi baseado no monitoramento de um reservatório tropical (Vargem das Flores) utilizado para o abastecimento público de água de sete cidades da região metropolitana de Belo Horizonte, Minas Gerais. O reservatório foi monitorado durante quatro anos: período inicial (de 2004 a 2007) para células de cianobactérias e parâmetros físico-químicos e, subsequentemente (2007 e 2008), para oocistos de Cryptosporidium spp. e cistos de Giardia spp. em quatro estações de amostragem. Também foram avaliadas as concentrações de Escherichia coli de 2007 a 2008, o que permitiu a caracterização de cada ponto de amostragem de acordo com a legislação do Conselho Nacional do Meio Ambiente (CONAMA) nº 274/2000. Os resultados indicaram concentrações de (oo)cistos de Cryptosporidium spp. e Giardia spp. variando de 0 a 0,8 (oo)cistos.L-1, e as mais elevadas concentrações de células de cianobactérias, de 0,0 a 4,5 x 105 cels.mL-1, apontando assim para potencial risco à saúde humana caso a água do reservatório seja consumida sem tramento. As cianobactérias não foram encontradas durante a estação seca. O grupo retornou rapidamente após a desestratificação. A estação chuvosa foi caracterizada pela elevada ocorrência de cianobactérias com a predominância da espécie picoplanctônica (Aphanocapsa sp.), sobre Microcystis spp. previamente detectada, e apresentou as maiores variações de oxigênio dissolvido, turbidez, fósforo total, ortofosfato, amônia, nitrito e nitrato. A mudança observada no grupo das cianobactérias (Aphanocapsa spp. sobre Microcystis spp.) pode ser um indicativo das alterações das características da água. De acordo com as concentrações de E. coli , as estações foram classificadas como próprias para recreação de contato primário, de acordo com a Resolução CONAMA nº 274/2000.The current study monitored the water quality of a tropical reservoir (Vargem das Flores) used to supply potable water to seven cities in the metropolitan area of Belo Horizonte, Minas Gerais, southeast Brazil. The reservoir was monitored for four years: initially (from 2004 to 2007) for cyanobacterial cells and physicochemical parameters and, subsequently (in 2007 and 2008), for Cryptosporidium spp. oocysts and Giardia spp. cysts in four sampling stations. The concentrations of Escherichia coli were also measured in 2007 and 2008, wich allowed the characterization of each sampling point according to the National Environment Council (CONAMA) no. 274/2000. Results indicated concentrations of Cryptosporidium spp. and Giardia spp. (oo)cysts ranging from 0 to 0.8 (oo)cysts.L-1, and higher concentrations of cyanobacteria cells, from 0.0 to 4.5 x 105 cells.mL-1, thus indicating potential risks to human health, if the water from the reservoir is not properly treated before consumption. The group of cyanobacteria was not found during the dry season, returning soon after destratification. The rainy season was characterized by a higher ocurrence of cyanobacteria and predominance of picoplanktonic species (Aphanocapsa spp.), over the Microcystis spp. previously found and presented the highest variations in dissolved oxygen, turbidity, total phosphorous, orthophosphate, ammonia, nitrite and nitrate. The change observed within the group of cyanobacteria (Aphanocapsa spp. over Microcystis spp.) may be indicative of changing characteristics in the water source. All the sampling points were classified as adequate for primary contact recreation, given the E. coli concentrations, according to the CONAMA Resolution no. 274/2000

Fundamentos Técnicos [unidade 02]

Mostra os conceitos envolvidos no abastecimento de água para consumo humano que são fundamentais para o aprimoramento do exercício das atividades relacionadas com a Vigilância da Qualidade da Água para consumo humano. Unidade 2 do Curso de Capacitação a Distância em Vigilância da Qualidade da Água para Consumo Humano.Versão 1Fundo Nacional de Saúd

Democratisation of Water and Sanitation Governance by Means of Socio-Technical Innovation. Participative Generation of a Water Treatment System in a Quilombola Community in Minas Gerais, Brazil (In Portuguese)

Case Study Report from the UE funded Project DESAFIO (Democratisation of Water and Sanitation Governance by Means of Socio-Technical Innovation), 2013-2015. www.desafioglobal.org. Published as WATERLAT-GOBACIT Working Papers, Vol. 2, No 12 (http://waterlat.org/WPapers/WPSPIDES212.pdf)

Socioeconomic, hygienic, and sanitation factors in reducing diarrhea in the Amazon

ABSTRACT OBJECTIVE To analyze the contributions of the socioeconomic, hygienic, and sanitation improvements in reducing the prevalence of diarrhea in a city of the Amazon. METHODS In this population-based cross-sectional study, we analyzed data from surveys conducted in the city of Jordão, Acre. In 2005 and 2012, these surveys evaluated, respectively, 466 and 826 children under five years old. Questionnaires were applied on the socioeconomic conditions, construction of houses, food and hygienic habits, and environmental sanitation. We applied Pearson’s Chi-squared test and Poisson regression to verify the relationship between origin of water, construction of homes, age of introduction of cow’s milk in the diet, place of birth and the prevalence of diarrhea. RESULTS The prevalence of diarrhea was reduced from 45.1% to 35.4%. We identified higher probability of diarrhea in children who did not use water from the public network, in those receiving cow’s milk in the first month after birth, and in those living in houses made of paxiúba. Children born at home presented lower risk of diarrhea when compared to those who were born in hospital, with this difference reversing for the 2012 survey. CONCLUSIONS Sanitation conditions improved with the increase of bathrooms with toilets, implementation of the Programa de Saúde da Família (PSF – Family Health Program), and water treatment in the city. The multivariate regression model identified a statistically significant association between use of water from the public network, construction of houses, late introduction of cow’s milk, and access to health service with occurrence of diarrhea

Socioeconomic, hygienic, and sanitation factors in reducing diarrhea in the Amazon

ABSTRACT OBJECTIVE To analyze the contributions of the socioeconomic, hygienic, and sanitation improvements in reducing the prevalence of diarrhea in a city of the Amazon. METHODS In this population-based cross-sectional study, we analyzed data from surveys conducted in the city of Jordão, Acre. In 2005 and 2012, these surveys evaluated, respectively, 466 and 826 children under five years old. Questionnaires were applied on the socioeconomic conditions, construction of houses, food and hygienic habits, and environmental sanitation. We applied Pearson’s Chi-squared test and Poisson regression to verify the relationship between origin of water, construction of homes, age of introduction of cow’s milk in the diet, place of birth and the prevalence of diarrhea. RESULTS The prevalence of diarrhea was reduced from 45.1% to 35.4%. We identified higher probability of diarrhea in children who did not use water from the public network, in those receiving cow’s milk in the first month after birth, and in those living in houses made of paxiúba. Children born at home presented lower risk of diarrhea when compared to those who were born in hospital, with this difference reversing for the 2012 survey. CONCLUSIONS Sanitation conditions improved with the increase of bathrooms with toilets, implementation of the Programa de Saúde da Família (PSF – Family Health Program), and water treatment in the city. The multivariate regression model identified a statistically significant association between use of water from the public network, construction of houses, late introduction of cow’s milk, and access to health service with occurrence of diarrhea

Recirculação de água de lavagem de filtros e perigos associados a protozoários Filter backwash water recycling and protozoan-related hazards

Apresentam-se, neste trabalho, os resultados (i) da caracterização da água de lavagem de filtros (ALF) da estação de tratamento de água da Universidade Federal de Viçosa (ETA- UFV); (ii) de ensaios de clarificação da ALF em colunas de sedimentação, com e sem uso de polímeros; (iii) de ensaios de recirculação de ALF em ETA piloto (EP), sob condições variadas de razão de recirculação (5 a 20% de incremento de vazão) e de turbidez da mistura de água bruta (AB) com ALF (12,1 a 257,3 uT). Na ALF foram encontradas concentrações em ordem de grandeza de 10¹ cistos de Giardia spp. e oocistos de Cryptosporidium spp. por litro. Os resultados dos ensaios em coluna de sedimentação e de recirculação na EP demonstraram que a clarificação da ALF com uso de polímeros contribui para a minimização de perigos associados à introdução de cistos de Giardia e oocistos de Cryptosporidium.<br>This paper presents the results of (i) the characterization of the filter backwash water (FBW) of Viçosa University water treatment plant; (ii) trials of FBW clarification in sedimentation columns, with and without polymer application; (iii) trials of FBW recycling in a pilot plant, under variable conditions of recycling flow rates (5 to 20% of the raw water flow - RW) and of the influent water (RW + FBW) turbidity (12.1 to 257.3 uT). Around 10¹ Giardia spp. cysts and Cryptosporidium spp. oocysts per liter were found in the FBW. The results of sedimentation columns and recycling trials demonstrated that FBW clarification using polymers contributes to minimize hazards related to the introduction of Giardia cysts and Cryptosporidium oocysts