Potable Water Reuse: What Are the Microbiological Risks?

Nappier, Sharon P.; Soller, Jeffrey A.; Eftim, Sorina E.

doi:10.1007/s40572-018-0195-y

Cited by 29 publications

(23 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reference pathogens are consistent with prior work and include norovirus, adenovirus, Cryptosporidium parvum , Giardia lamblia , Campylobacter jejuni , and Salmonella enterica . − These reference pathogens represent the major portion of all non-food-borne illnesses from known pathogens in the United States, are representative of other pathogens potentially of concern from the water-borne exposure route, and have peer-reviewed dose–response relationships − (Table S1). Although there are some concerns within the engineering community regarding the use of norovirus as a reference pathogen for potable reuse, there is a strong and growing consensus among microbiologists and risk assessors ,− about its utility and use for this purpose as being representative of the myriad nonculturable viruses that make up the majority of illnesses in the U.S. population. , …”

Section: Materials and Methodsmentioning

confidence: 99%

Public Health Implications of Short Duration, Off-Specification Conditions at Potable Reuse Water Treatment Facilities

Soller¹,

Parker²,

Salveson³

2018

Environ. Sci. Technol. Lett.

Self Cite

View full text Add to dashboard Cite

Recycled water is an increasingly important water supply component for many communities. Widespread success with nonpotable reuse, and indirect potable reuse (IPR) such as groundwater injection, has an increasing number of municipalities considering potable reuse without the use of an environmental buffer [direct potable reuse (DPR)]. Previous risk assessment studies have evaluated the microbiological risks associated with potable reuse. However, no studies have rigorously evaluated the potential public health implications of known, infrequent, and short duration, off-specification conditions in advanced water treatment facilities (“off-spec events”). Herein, we couple previously reported data describing the frequency and severity of off-spec events with a microbial risk assessment methodology to quantitatively characterize the public health implications of these off-spec events. The results indicate that these low-probability, short duration, off-spec events in a potable reuse treatment system can drive annual risks; predicted annual median risk differences were increased by up to ∼4 orders of magnitude. The use of accurate monitoring of performance surrogates and diversion [e.g., engineered storage buffer (ESB)] allows for these increased risks to be minimized. These results highlight the importance of understanding water treatment system operations on a real-time basis and point toward managing plant operations and off-spec events in real time to maintain public health protection.

show abstract

Section: Materials and Methodsmentioning

confidence: 99%

Public Health Implications of Short Duration, Off-Specification Conditions at Potable Reuse Water Treatment Facilities

Soller¹,

Parker²,

Salveson³

2018

Environ. Sci. Technol. Lett.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Previously, a systematic review methodology was developed to evaluate densities of key viruses in raw wastewater and published distributions of norovirus densities in raw wastewater (Eftim et al 2017). These distributions are specifically useful for conducting quantiative microbial risk assessments (QMRA) (Soller et al 2018;Nappier et al 2018). For the derivation of coliphage-based recreational water quality criteria values, similar distributions of MSC and SC in raw wastewater and ambient waters are needed.…”

Section: Introductionmentioning

confidence: 99%

Occurrence of coliphage in raw wastewater and in ambient water: A meta-analysis

et al. 2019

Self Cite

View full text Add to dashboard Cite

Coliphage have been proposed as indicators of fecal contamination in recreational waters because they better reflect the persistence of pathogenic viruses in the environment and through wastewater treatment than traditional fecal indicator bacteria. Herein, we conducted a systematic literature search of peer-reviewed publications to identify coliphage density data (somatic and male-specific, or MSC) in raw wastewater and ambient waters. The literature review inclusion criteria included scope, study quality, and data availability. A non-parametric two-stage bootstrap analysis was used to estimate the coliphage distributions in raw wastewater and account for geographic region and season. Additionally, two statistical methodologies were explored for developing coliphage density distributions in ambient waters, to account for the nondetects in the datasets. In raw wastewater, the analysis resulted in seasonal density distributions of somatic coliphage (SC) (mean 6.5 log 10 plaque forming units (PFU)/L; 95% confidence interval (CI): 6.2-6.8) and MSC (mean 5.9 log 10 PFU/L; 95% CI: 5.5-6.1). In ambient waters, 49% of MSC samples were nondetects, compared with less than 5% for SC. Overall distributional estimates of ambient densities of coliphage were statistically higher for SC than for MSC (mean 3.4 and 1.0 log 10 PFU/L, respectively). Distributions of coliphage in raw wastewater and ambient water will be useful for future microbial risk assessments.

show abstract

“…Approximately 200 species of enteric viruses can be present in untreated wastewater (Gerba et al, 2017), including noroviruses, enteroviruses (e.g., poliovirus, hepatitis A, and rotaviruses), and adenoviruses (Nappier et al, 2018). Bacterial indicators including total and fecal coliform and Escherichia coli ( E. coli ) can be used as a surrogate to detect pathogens (Odonkor & Ampofo, 2013; Wang et al, 2013; Wu et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

Pathogen reduction by ozone–biological activated carbon‐based advanced water reclamation for reuse

Teel

Pagilla

Lin

et al. 2022

Water Environment Research

View full text Add to dashboard Cite

Ozone-biological activated carbon (ozone-BAC)-based technologies are emerging as an appealing option for potable reuse systems; however, uncertainty remains regarding the reduction of waterborne pathogens. Common log reduction requirements have been modeled after California Department of Drinking Water's 12-10-10 log reduction value (LRV) for enteric virus, Cryptosporidium, and Giardia, respectively. The objective of this research was to investigate appropriate LRVs of pathogens that can be achieved in ozone-BAC-based treatment systems and to assess the applicability of employing drinking water pathogen guidelines for potable reuse applications. A pilot scale ozone-BAC-based treatment train was operated at two water reclamation facilities in Reno, Nevada, USA. Virus, Cryptosporidium, Giardia, and bacterial indicators were monitored across individual and combined treatment processes. Pathogen barriers investigated include conventional filtration, ozonation, and ultraviolet disinfection. Based on sampling and treatment validation strategies, the three pathogen barriers can provide minimum LRVs of 13-9-9.5 for virus, Giardia, and Cryptosporidium. Secondary biological treatment can provide additional pathogen LRVs with site-specific sampling. The present study addresses regulatory uncertainties associated with ozone-BAC pathogen reduction. Practitioner Points • Ozone-biological activated carbon-based advanced treatment can meet pathogen LRV requirements with a minimum of three pathogen barriers. • Successfully applied drinking water pathogen reduction guidelines for potable reuse applications verified by operational criteria. • Low presence of pathogens requires surrogates and indicator analyses and variety of monitoring techniques to verify pathogen log reduction. K E Y W O R D S log 10 reduction values, ozone-biological activated carbon, water reclamation, water reuse, waterborne pathogens Krishna Pagilla is a member of the Water Environment Federation (WEF).

show abstract

Potable Water Reuse: What Are the Microbiological Risks?

Cited by 29 publications

References 47 publications

Public Health Implications of Short Duration, Off-Specification Conditions at Potable Reuse Water Treatment Facilities

Public Health Implications of Short Duration, Off-Specification Conditions at Potable Reuse Water Treatment Facilities

Occurrence of coliphage in raw wastewater and in ambient water: A meta-analysis

Pathogen reduction by ozone–biological activated carbon‐based advanced water reclamation for reuse

Contact Info

Product

Resources

About