Comparison of the quantity and quality of the microbiological content of sludge in countries with low and high content of pathogens

Abstract

The parasites present in the residual sludge generate by the diverse treatment processes of residual water vary, depending on the socioeconomic and epidemiological conditions of different communities. And although data exist at the global level regarding the microbiological quality of sludge, these data are practically nonexistent in developing countries. Therefore, this project compares the content of the four principal groups of parasites in residual sludge from the United States and Mexico. The marked differences between the orders of magnitude found in the two countries (coliphages 10(3)-10(6) and 1.3 x 10(5) PFU/gTS, fecal coliforms 10(7)-10(10) and 10(7), Salmonella typhi 10(6)-10(8) and 10(3) MPN/gTS, Giardia lamblia 10(2)-10(4) and 10(2) cysts/gTS and helminth ova from 73-177 and <1 to 10 viable HO/gTS, respectively) will permit proposing real, effective and economical stabilization processes (undoubtedly different from those of industrialized countries), and will thus take advantage of the benefits represented by the reuse and disposal of sludge, in addition to developing regulations in agreement with the conditions of each region.

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

“…The concentration of Giardia cysts found in this study (0 to 4800 cysts/g), corroborates what was reported by Hu et al (1996) For oocysts, the number of positive samples identified in this study (8.3 %) was lower than has been reported in previous studies in other countries (Jiménez et al 2002, Lemarchand and Lebaron 2003, Thiriat et al 1997). This may be explained by several factors, including the prevalence of cryptosporidiosis in those communities and the individual characteristics, such as pH, of the sludge matrix studied.…”

“…Jiménez et al (2002) assessed the viability of Ascaris eggs in sewage sludge samples in Mexico by employing purification technique with steps of washing, filtration, flotation in saturated and centrifugal concentration and then incubated for 20 days at 26°C sulfuric acid (0.05 mol/L). According to the authors, Ascaris eggs were found more frequently when compared to other helminth whereas 90 % of them were viable.…”

“…The occurrence of diseases caused by viruses, protozoa and helminth pathogenic shows that the traditional indicator bacteria are unsuitable as the only indicators for safe disposal of sludge due to strong resistance to various traditional processes of removal as well as protozoa and helminths destruction (Jiménez et al 2002;Guadagnini et al 2013). The use of helminth eggs as an indicator to monitor the presence of pathogens in biosolid is based on the premise that present high rate of survival (years) compared to bacteria (months) and protozoa (months) and resistance to chlorination processes and high temperature (Jenkins et al 1998, Shamma andAl-Adawi 2002).…”

Using Ecosan sludge for crop production

“…Also, very frequently, Ascaris eggs are common in wastewater and sludge (Cabaret et al, 2001, andJiménez et al, 2002). For this reason, in regulations and very often in research studies, Ascaris is the only helminth considered.…”

Municipal Wastewater Management in Developing Countries - Principles and Engineering

“…There is not an indicator of this group, but it is generally accepted that they are less resistant than helminth ova to adverse environmental conditions. Table 10.4 Pathogens found in wastewater and sludge (EPA, 1994 andJimenez, 2003 Jiménez et al, 2002. Helminth Ova.-Helminth ova are a special challenge in the field of sludge treatment processes, due to their very high resistance to extreme conditions.…”