scholarly journals Monitoring Opportunistic Pathogens in Domestic Wastewater from a Pilot-Scale Anaerobic Biofilm Reactor to Reuse in Agricultural Irrigation

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1283 ◽  
Author(s):  
Bingjian Cui ◽  
Shengxian Liang

Wastewater reuse for agricultural irrigation in many developing countries is an increasingly common practice. Regular monitoring of indicators can help to identify potential health risks; therefore, there is an urgent need to understand the presence and abundance of opportunistic pathogens in wastewater, as well as plant phyllosphere and rhizosphere. In this study, an anaerobic biofilm reactor (ABR) was developed to treat rural domestic wastewater; the performance of pollutants removal and pathogenic bacteria elimination were investigated. Additionally, we also assessed the physicochemical and microbiological profiles of soil and lettuces after wastewater irrigation. Aeromonas hydrophila, Arcobacter sp., Bacillus cereus, Bacteroides sp., Escherichia coli, Legionella sp., and Mycobacterium sp. were monitored in the irrigation water, as well as in the phyllosphere and rhizosphere of lettuces. Pathogens like B. cereus, Legionella sp. and Mycobacterium sp. were present in treated effluent with relatively high concentrations, and the levels of A. hydrophila, Arcobacter sp., and E. coli were higher in the phyllosphere. The physicochemical properties of soil and lettuce did not vary significantly. These data indicated that treated wastewater irrigation across a short time period may not alter the soil and crop properties, while the pathogens present in the wastewater may transfer to soil and plant, posing risks to human health.

2004 ◽  
Vol 50 (2) ◽  
pp. 293-300 ◽  
Author(s):  
M. Platzer ◽  
V. Cáceres ◽  
N. Fong

The first subsurface flow wetland (SSFW) system for about 1,000 PE, was constructed in Nicaragua in 1996 to apply this technology in the form of an integral project, combining the treatment of domestic wastewater with its reuse for crop production in small and medium size communities. The SSFW-effluent meets all standards established in the national regulations for wastewater reuse in agriculture, except for faecal coliforms, existent at an average concentration of 7 × 104 MPN/100 ml. A conventional surface irrigation method was used to irrigate different crop species selected to establish their risk of contamination. To judge the potential health risk for consumers and farmers, samples of vegetables and fruits harvested in the dry seasons of the years 1997 to 2002, were analyzed for the presence of pathogenic microorganisms like faecal coliforms, salmonella and shigella. In addition, a yield comparison between crops irrigated with well water using chemical fertilizers, and crops irrigated with the effluent of the SSFW-system was made, to analyze the economical benefits of the wastewater reuse.


2015 ◽  
Vol 17 (2) ◽  
pp. 357-369 ◽  

<div> <p>The aim of this paper is to highlight the way towards the exploitation of treated wastewater for food crops production in order to cope with the acute water scarcity and its hazardous consequences. Reclaimed water reuse has not been practiced in Tobruk, and hence, lack of relevant data and information was the major difficulty in carrying out this research. The existing sewage treatment plant in Tobruk city produces about 7,000 cubic meters per day of suitable effluent for agricultural irrigation and safe discharge. This proportion is worth twice as much as the water being currently used for irrigation. Therefore, with proper planning and management, treated wastewater reuse schemes, in addition to their economical and environmental benefits, can be an efficient mechanism to cope with water shortage and reducing the high burden placed on the desalination plant. Wastewater reuse is considered as a reliable, secure, and drought-resistant water source. Owing to the lack of disinfection processes and routinely monitoring data, there is uncertainty concerning the microbiological safety and quality of the treated effluent. Public perception might be the major challenge facing the planning for a reuse scheme as 51 % of the population of Tobruk have shown their reluctance to consume food crops irrigated with treated wastewater. Nonetheless, public attitudes can be fostered by awareness through the media as some people, when the issue was discussed, have shown a positive response. In fact their main concerns were related to public health safety and potential negative environmental impacts which can be addressed through good planning and prudent management.</p> </div> <p>&nbsp;</p>


1999 ◽  
Author(s):  
Gideon Oron ◽  
Raphi Mandelbaum ◽  
Carlos E. Enriquez ◽  
Robert Armon ◽  
Yoseph Manor ◽  
...  

The main purpose of the research was to examine approaches and to evaluate methods for minimizing the risks during applying treated domestic wastewater for agricultural irrigation. This general purpose consisted of examining under field conditions the possibilities when implementing different application technologies for minimizing health and environmental risks. It was assumed that Subsurface Drip Irrigation (SDI) will provide adequate conditions for safe effluent reuse. Controlled field experiments where conducted in commercial fields to evaluate the alternatives. Main efforts where conducted in Israel in the grape vineyard in Arad heights, in the field crops in Kibbutz Chafets Chaim and in Arizona in fields adjacent to the University campus. The complementary part was to examine the behavior of the various pathogens in the effluent-soil-plant system. The analysis is based on controlled experiments, primarily in greenhouse along with field experiments. Molecular biology methods were used to identify the behavior of the pathogens in the components of the system. The project included as well examining the effluent quality in various sites, primarily those in which treated wastewater is reused for agricultural irrigation. The monitoring included conventional parameters however, also parasites such as Giardia and Cryptosporidium. The results obtained indicate the prominent advantages of using Subsurface Drip Irrigation (SDI) method for minimizing health and environmental risks during application of secondary effluent. A theoretical model for assessing the risks while applying treated wastewater was completed as well. The management model shows the risks during various scenarios of wastewater quality, application technology and related human exposure.


2019 ◽  
Vol 11 (21) ◽  
pp. 5936 ◽  
Author(s):  
Jack E. Beard ◽  
Marc F.P. Bierkens ◽  
Ruud P. Bartholomeus

De facto (or indirect) wastewater reuse is the practice of extracting from surface water bodies which are impacted by treated wastewater (TWW) for anthropogenic use. The extent to which surface water bodies in the Netherlands are impacted by TWW is poorly understood, and the distribution of de facto reuse even more so. This study addresses these knowledge gaps, with a focus on reuse for agricultural irrigation. This is achieved via a novel application of the Water Framework Directive (WFD) Explorer water quality model, allowing for the distribution of different flow components—namely TWW and flow from transboundary rivers—to be discerned for the national surface water network. When paired with data on surface water extractions for irrigation, this identifies notable areas of de facto reuse. Results show that during dry conditions, TWW is a significant flow component in many surface water bodies, particularly in smaller streams located close to WWTPs. De facto reuse is indicated as widespread, with several key areas identified in which extractions are from impacted surface water bodies. This study represents a first attempt to directly link TWW emissions to agricultural irrigation, highlighting a mechanism by which wastewater-associated contaminants can propagate through the hydrological system.


1986 ◽  
Vol 18 (9) ◽  
pp. 147-162 ◽  
Author(s):  
H. I. Shuval ◽  
B. Fattal ◽  
P. Yekutiel

The reuse of wastewaters for agricultural irrigation can be a means of reducing the pollution of surface waters including those in coastal areas used for bathing. The wastewater stream of a community carries within it the complete spectrum of pathogenic bacteria, viruses, protozoa and helminths which are endemic in the community. These pathogens can survive sufficiently long in the soil or on crops to infect, at least in theory, persons coming in direct contact. Thus, it is important to establish a sound epidemiological basis for health regulations related to the reuse of wastewater in agriculture. This paper presents the theoretical epidemiological considerations that should serve as the basis for a predictive model of the potential risks associated with wastewater irrigation. Empirical data from credible, quantifiable epidemiological studies have here been reviewed to validate the theoretical model. For developing countries, the authors have concluded that the ranking of pathogens as to the degree of risk associated with wastewater irrigation is as follows: high risk - helminths, medium risk - bacteria and protozoa and low risk - viruses.In order to effectively reduce the concentration of these pathogens wastewater treatment is recommended as the most effective control strategy.


2021 ◽  
Author(s):  
María Laura Gatto D'Andrea ◽  
Martín Alejandro Iribarnegaray ◽  
Walter Alfredo Tejerina ◽  
Ariela Griselda Judith Salas Barboza ◽  
Juan José Correa ◽  
...  

A model of land suitability analysis for irrigation with treated domestic wastewater is presented. The model integrates tools of Multi-Criteria Evaluation with Geographical Information Systems. Several criteria were selected to adapt the model to the conditions and characteristics of the case study. The adaptation process included field visits, a bibliographical review, and personal interviews with local actors and experts. Six constraints and 10 factors were selected and 3158 hectares suitable for the activity were identified. The areas were classified into three categories of aptitude, representing high fitness sites close to the current wastewater treatment plant. The developed tool allowed us to integrate different criteria to assess site suitability for wastewater reuse, with the advantage that the tool can be adapted to other regions and/or objectives.


1996 ◽  
Vol 33 (10-11) ◽  
pp. 355-362 ◽  
Author(s):  
Oscar Vazquez-Montiel ◽  
Nigel J. Horan ◽  
Duncan D. Mara

Treated effluent from an aerated lagoon and facultative pond system in southern Portugal, was used to irrigate fields planted to maize (Zea mays L.). The effluent was characterised with respect to its nitrogen and phosphorus content and applied by drip irrigation in response to crop evapotranspiration requirements. Nitrification of ammonia in the effluent by soil microorganisms caused a reduced soil pH early in the growing season, but this was reversed as the season continued. For most of the growth season plant nitrogen demand ensured a low soil nitrogen concentration, but towards the end of plant growth the continuous nitrogen supplied in the effluent exceeded crop requirements with a result that nitrate accumulated in the soil. The applied effluent also had a high phosphorus concentration but there was only a slight accumulation of this in the soil. The fertiliser value of the treated effluent was demonstrated by increased yields at physiological maturity and the N yield was within the range of expected values for this crop. The main removal mechanism for N during irrigation was crop uptake whereas P was removed primarily by soil processes. The advantages of wastewater reuse together with the importance of appropriate management practices for re-use are discussed.


1989 ◽  
Vol 21 (6-7) ◽  
pp. 421-426 ◽  
Author(s):  
Shamim Ahmad

Excessive use of potable water in irrigation can be reduced considerably through treated wastewater reuse specially when fresh water resources in Qatar are scarce and the water supply depends on the limited groundwater and costly desalinated water. In view of the use of treated effluent in irrigation, the infiltration of brackish groundwater into the sewerage system should be eliminated and stringent standards to control leakages should be laid for new construction. The wastewater treatment methods and the effluent quality in general meet the criteria and standards governing the use of effluent in irrigation of landscape and agriculture. The reuse plan controls pollution by eliminating discharge of the wastewater to the gulf and contributes to the aesthetic and economic value of the area. The development of green areas along the roadside reservations and sidewalks through effluent reuse has been successful.The cultivation of fodder crops and development of forestry through effluent irrigation in agricultural farms far from the centre of population seems feasible and safe. However it is necessary to consider and evaluate the social and religious factors at the planning stage of the reuse schemes. With adequate planning,surviellance programme,health education,training of workers and awareness amongst the population, effluent reuse can be practised with minimum health risk and confidence can be established in the users.


2011 ◽  
Vol 63 (1) ◽  
pp. 143-148 ◽  
Author(s):  
E. E. Schneider ◽  
A. C. F. P. Cerqueira ◽  
M. Dezotti

This work evaluated the performance of a Moving Bed Biofilm Reactor (MBBR) in the treatment of an oil refinery wastewater. Also, it investigated the possibility of reuse of the MBBR effluent, after ozonation in series with a biological activated carbon (BAC) column. The best performance of the MBBR was achieved with a hydraulic retention time (HRT) of 6 hours, employing a bed to bioreactor volume ratio (VB/VR) of 0.6. COD and N-NH4+ MBBR effluent concentrations ranged from 40 to 75 mg L−1 (removal efficiency of 69–89%) and 2 to 6 mg L−1 (removal efficiency of 45–86%), respectively. Ozonation carried out for 15 min with an ozone concentration of 5 mg L−1 was able to improve the treated wastewater biodegradability. The treatment performance of the BAC columns was practically the same for ozonated and non ozonated MBBR effluents. The dissolved organic carbon (DOC) content of the columns of the activated carbon columns (CAG) was in the range of 2.1–3.8 mg L−1, and the corresponding DOC removal efficiencies were comprised between 52 and 75%. The effluent obtained at the end of the proposed treatment presented a quality, which meet the requirements for water reuse in the oil refinery.


Sign in / Sign up

Export Citation Format

Share Document