Pathogenic parasites and enteroviruses in wastewater: support for a regulation on water reuse

Abstract

Brazilian regulations for nonpotable reuse are being established using World Health Organization guidelines, however, they should be developed based on local monitoring studies. This study intended to analyze enteroviruses, protozoa and viable Ascaris sp. eggs in raw (24) and treated (24) effluents from four Wastewater Treatment Plants of São Paulo State, Brazil. The protozoa were detected with the US Environmental Protection Agency (USEPA) Method 1623 in the treated effluents and by centrifugation/Immunomagnetic Separation in the raw influent samples. Viable Ascaris sp. eggs were analyzed according to a modified USEPA method. Enteroviruses were quantified by using human rhabdomyosarcoma cells after adequate concentration procedures. All wastewater influents were positive for Giardia sp. whereas Cryptosporidium sp. was detected in 58.3% of the samples. Giardia sp. and Cryptosporidium sp. were present in 79.2 and 25.0% respectively, of the treated wastewater samples. Viable Ascaris sp. eggs were detected in 50.0 and 12.5% of influent and treated wastewater samples. Enteroviruses were isolated in the 24 raw influent samples and in 46% of the treated samples. Taking into account the densities of Giardia sp. in some treated wastewaters intended to be used as reclaimed water, Quantitative Microbial Risk Assessment studies should be conducted to establish pathogen quantitative criteria for a future Brazilian regulation for water reuse.

Real scale environmental monitoring of zoonotic protozoa and helminth eggs in biosolid samples in Brazil

“…With the population increase and urbanization, biosolid production also has increased and the application of this residue to soil for fertilization purpose represents the best option for disposal as this is rich in nutrients (Guadagnini et al 2013;Hachich et al 2013;Lima et al 2012;Lu et al 2012;Silva et al 2012). However, inherent in its use in agriculture are concerns about its effects on public health due to uncertainties surrounding the presence of enteric parasites, which can be sources of contamination in both food and surface water and groundwater; the low infective dose of certain pathogens, especially Cryptosporidium and Giardia; the possible growth of pathogenic bacteria, such as coliforms, which are used as indicators of safety but do not predict the presence of other pathogens (Abreu-Acosta and Vera 2011); and the potential for diseases caused by unknown agents (Santamaria andToranzos 2003, Sidhu andToze 2009).…”

Giardia duodenalis

“…Similarly, in Norway (Robertson et al, 2006) and Spain (Castro-Hermida et al, 2010), high numbers of cysts were found in raw sewage influent samples that contained from 10 2 to 1.36x10 4 cysts/L and 2 to 1.44x10 4 cysts/L. In Brazil, cysts were detected at concentrations as high as 10 5 cyst/L (Neto et al, 2006;Hachich et al, 2013). In contrast, relatively few studies have reported cysts at concentrations not exceeding 100 cysts/L (Reinoso et al, 2011;Yapo et al, 2014;Zhang et al, 2015).…”

“…High prevalence rates of Giardia in raw wastewater were reported in both developed and developing countries. Surveys undertaken in North America (Harwood et al, 2005;Kitajima et al, 2014), Europe (Cacciò et al, 2003;Reinoso et al, 2011;Rodriguez-Manzano et al, 2012), Asia (Oda et al, 2005;Lim et al, 2007;Ma et al, 2016) and South America (Hachich et al, 2013) reported the presence of cysts in up to 100% of the raw sewage influent samples tested. The number of cysts /L of raw sewage was found to vary from hundreds to thousands.…”

Quantificação e caracterização genotípica de Cryptosporidium spp.isolados de água bruta superficial e esgoto bruto para a monitorização em mananciais de abastecimento público na Região Metropolitana de São Paulo (RMSP)

“…Cryptosporidium é desenvolvida em centros de pesquisas (FRANCO et al, 2001;SANTOS et al, 2004;HACHICH et al, 2004;MACHADO et al, 2009;RAZZOLINI et al, 2010; ARAUJO et al, 2011;HACHICH et al, 2013; BONATI & FRANCO, 2014). Entretanto, a detecção de Cryptosporidium em amostras de águas continua sendo um desafio, sobretudo no Brasil, devido à inexistência de dados epidemiológicos de surtos de criptosporidiose, e à dificuldade de implementação e otimização de métodos de detecção e quantificação acessíveis, em termos de custos, e reprodutíveis quando aplicados nas águas dos manaciais do nosso país (ARAUJO et al, 2011).…”

“…Cryptosporidium é desenvolvida em centros de pesquisas (FRANCO et al, 2001;SANTOS et al, 2004;HACHICH et al, 2004;MACHADO et al, 2009;RAZZOLINI et al, 2010;ARAUJO et al, 2011;HACHICH et al, 2013;BONATI & FRANCO, 2014 ou sequenciamento do fragmento para estudo de posicionamento taxonômico dos organismos a fim de melhorar a efetividade na investigação e aperfeiçoar o processo, tornando-o mais rápido (HIGGINS et al, 2003;ZHOU et al, 2003;XIAO et al, 2004;RYAN et al, 2005;ARAUJO, 2008;PLUTZER e TOMOR, 2009 MEYER et al, 2010).…”