Article pubs.acs.org/est
Development of a Novel Filter Cartridge System with Electropositive Granule Media to Concentrate Viruses from Large Volumes of Natural Surface Water Min Jin,† Xuan Guo,† Xin-Wei Wang, Dong Yang, Zhi-Qiang Shen, Zhi-Gang Qiu, Zhao-Li Chen, and Jun-Wen Li* Department of Environment and Health, Institute of Health and Environmental Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China S Supporting Information *
ABSTRACT: Exposure to various infectious viruses in environmental drinking water can constitute a public health risk. However, it is difficult to detect viruses in water due to their low concentration. In this study, we have developed a novel filter cartridge system containing electropositive granule media (EGM). Viruses present in large volumes of environmental samples were adsorbed onto the EGM, and then recovered by elution and poly(ethylene glycol) (PEG) concentration. To evaluate the system’s efficiency in viral recovery, poliovirus (PV-1), a surrogate for enteric viruses, was used to artificially contaminate river water samples which were then assayed by quantitative real-time PCR. To optimize the concentration procedure, the eluent type, water flow rate and properties (e.g., pH, bacterial, and viral loads), were evaluated. The highest virus recovery was obtained by pumping river water at a flow rate of 300 mL/min and then pushing 3 L of an eluent containing 3× broth [1.5% (w/v) NaCl, 3% (w/v) tryptone, 1.5% (w/v) beef powder] with 0.05 mol/L glycine through the filter. Using this procedure, the recovery efficiencies of PV-1 from 10 to 100 L of spiked river water were up to 99%. In addition, this method is virus load and pH dependent. Virus recovery was maximal at a load of between 103.5 and 105.5 TCID50 and a pH ranging from 5 to 7. The bacterial load in the water has no effect on virus recovery. Different types of viruses and surface water were tested to validate the system’s applicability. Results revealed that the EGM filter cartridge was able to concentrate PV-1, human adenoviruses (HAdVs) and noroviruses (HuNoVs) with high efficiency from river, lake, and reservoir water. Furthermore, it showed more efficient recovery than glass wool and 1MDS filters. These data suggest that this system provides rapid and efficient virus recovery from a large volume of natural surface water and, as such, could be a useful tool in revealing the presence of viruses in surface water. determine the epidemiology of circulating enteric viruses,11 and to better control waterborne outbreaks caused by viruses.12−17 However, due to the low amounts of viral particles present in natural surface water [ 0.05, Figure 6a). In addition, the EGM filter cartridge system had low bacterial recovery. Less than 20% of the input E. coli was recovered from both the first-stage elution solution and final buffered virus concentrate (SI Figure S10). Furthermore, virus recovery was investigated at different pH values of river water by adjusting the pH between 3.0 and 10.0 using 1 mol/L HCl or NaOH. Similar to the pH dependence of other virus concentration techniques relying on electronegative and electropositive media,34,37 the recovery efficiency of the cartridge system with EGM was significantly affected by the pH of the water. Our results show that virus recovery was maximal at a pH range of between 5 to 7 (p > 0.05, Figure 6b). Virus recovery declined substantially with increasing or decreasing pH, reaching a value of less than 10% at pH 10 and pH 3. Validation of Virus Concentration using the Filter Cartridge with EGM. To further validate the applicability of the filter cartridge system with EGM, 20 L samples of surface water sourced from the Haihe river (n = 3), Jinhe river (n = 3), Tuanbo lake (n = 3) and Yunqiao reservoir (n = 3) were spiked with 1 × 106.5 TCID50 of PV-1 [(1.8 ± 0.37) × 108 GCs],
Figure 4. Recovery of spiked PV-1 from 20 L of river water using the filter cartridge under different water flow rates and assayed by RTqPCR (n = 3). No environmental/background HRV were found and the mean concentration of background PV-1 in the tested water was calculated as 80 GCs/L by RT-qPCR.
between the recovery yields of PV-1 under different water flow rates (p < 0.05). An average of 71% PV-1 recovery was obtained at a water flow rate of 300 mL/min. Once the water flow rate was over 500 mL/min, less than 50% of viruses were recovered. Virus Recovery from 10 L, 20 or 100 L River Water Samples Spiked with Different Virus Concentrations by the Filter Cartridge with EGM. Figure 5 shows the recovery yields of PV-1 assayed by RT-qPCR from 10 L, 20 L, and 100 L of river water spiked with approximately 103.5−109.5 TCID50 of PV-1 [(7.9 ± 2.47) × 105 GCs − (8.0 ± 1.63) × 1010 GCs] using the filter cartridge with EGM (flow rate of 300 mL/min). It shows that viral inputs clearly affect the recovery yields, but there were no significant differences between virus recoveries from different river volumes with the same virus input. When PV-1 inputs ranged from 103.5 to 105.5 TCID50 [(7.9 ± 2.47) × 6952
dx.doi.org/10.1021/es501415m | Environ. Sci. Technol. 2014, 48, 6947−6956
Environmental Science & Technology
Article
Figure 6. Virus Recovery from 20 L of river water using the filter cartridge under different E. coli concentrations (a) and pH (b) conditions and assayed by RT-qPCR (n = 3). Approximately 106.5 TCID50 of PV-1[(1.9 ± 0.95) × 108 GCs)] was spiked into the river water samples. No environmental/background HRV were found and the mean concentration of background PV-1 in the tested water was calculated as 3.9 × 103 GCs/L by RT-qPCR. The mean values for total bacteria (TB) and total coliform (TC) in the river water (background) were 2300 and 300 CFU/mL, respectively.
HAdV 41 [(3.7 ± 1.26) × 108 GCs] and of HuNoV GII [ (2.7 ± 0.21) × 106 GCs], respectively. The samples were then used to determine virus recovery from the filter cartridge system. Although viruses differ in their electronegativity and, therefore, in their binding efficiency to electropositive filters, the results demonstrated that the filter cartridge system with EGM had an excellent capacity to concentrate viruses from natural surface water. Each virus tested could be recovered from the four water types at a high efficiency. Average virus recovery was over 87% (SI Table S1). Comparative Study of the Virus Concentration Methods. PV-1 recoveries from the 20 L of spiked river water samples using the filter cartridge with EGM were compared with those using the glass wool filters and the 1MDS filters. The results demonstrated that the filter cartridge with EGM showed almost perfect adsorption of PV-1 and that its average recovery of PV-1 from river water reached 99% from an input of 103.8 TCID50-104.8 TCID50 [(7.8 ± 1.52) × 105 GCs − (6.3 ± 1.07) × 107 GCs] whereas the glass wool and the 1MDS filters showed less than 50% virus recovery, respectively. The mean recoveries of each concentration are presented in SI Table S2. Therefore, virus recovery using the filter cartridge with EGM was the highest, resulting in a statistically significant difference between the other two concentration methods (p < 0.05).
Viruses will be positively charged below their isoelectric point (IEPs), and negatively charged above the IEP. Generally, the IEPs of viruses are within the 1.9−8.4 pH range and so, the net electrostatic charge of most viruses such as PV-1 will be negative45 at the pH of natural surface water, which ranges from 6 to 9. The IEP of Al(OH)3 precipitate is between 8.5 and 9.3, and so the EGM will be positively charged at pH 6−9 facilitating the absorption and concentration of negatively charged viruses from water. For the same reasons, the EGM surface would become negatively charged on exposure to a solution at high pH, creating unfavorable conditions for viruses to absorb. However, in practice, this is not the case because there are still many other factors that limit virus recovery including the physicochemical properties of the surrounding aqueous environment (e.g., ionic strength), and the presence of organic compounds.25 In this study, several other important factors were found to contribute to the high virus recovery of the EGM filter. First, it is the fundamental to have a high virus binding capacity. The binding capacity of the filter depends on the negative or positive charge loads on the media surface, which is associated with the specific surface area and zeta potential of electropositive media under a given condition. In this study, the EGM has an extensive surface area (500 m2/g) compared with glass wool and Zeta Plus Virosorb 1MDS. It also possessed a strongly positive electrophoretic mobility at a pH ranging from 5 to 8 and showed strong virus binding characteristics in that pH range. Correspondingly, the high surface area coupled with the relatively high isoelectric point (IEP range = 8.5 to 9.3) confers a strong electropositivity and binding capacity to the filter surface, which is higher than that of glass wool and Zeta Plus Virosorb 1MDS. Second, the water flow rate, which determines the contact time between viruses and cations on the EGM, is also a key parameter determining virus recovery. Generally, with an increase in water flow rate, virus recovery decreases. We observed that the optimal flow rate of 300 mL/ min resulted in high recovery efficiencies using this method. 1MDS and NanoCeram filters use increased flow rates to prevent clogging (an average flow rate of 5.6 L/min), which can result in low virus recovery.36,46 Finally, the biological properties of water, particular viral loads, had a notable effect on virus recovery. For example, the filter cartridge in this study was filled with 600 g of EGM, and thus the positive charge load
4. DISCUSSION In this study, we have developed a novel and convenient filter cartridge system with EGM to concentrate viruses from large volumes of natural surface water even at high turbidities (10− 32 NTU). Although the values of viral recoveries vary for the different conditions, this study demonstrates that high recoveries of above 99% were achieved for 10 3.5−10 5.5 TCID50 or 7.9 × 105 − 4.9 × 107 GCs of virus load from 10 to 100 L of natural surface water and that this method was more effective than others published elsewhere15,26,33,36,44 (SI Table S3). Importantly, the filter cartridge with EGM requires no clarification of surface water, and so viruses in river water that adsorbed onto solid matrices by electrostatic interactions were also recovered by alkaline elution which may result in higher virus recovery than other reported methods. In addition, the adsorption of bacteria present in the water samples does not affect virus recovery. 6953
dx.doi.org/10.1021/es501415m | Environ. Sci. Technol. 2014, 48, 6947−6956
Environmental Science & Technology
Article
Information. This material is available free of charge via the Internet at http://pubs.acs.org/.
on the media surface (i.e., the binding capacity for virus), was limited. Once the charged media was saturated with viruses or other negative particles, no more virus absorption occurred and virus recovery decreased accordingly. Our results suggest that high virus recovery of 99% was achieved with the filter cartridge from 10 up to 100 L of river samples spiked with below 105.5 TCID50 PV-1 (4.9 × 107 GCs). If the PV-1 load was too high (i.e., 108.5 TCID50) and beyond the binding capacity of the filter, virus recovery declined drastically to less than 10%. Fortunately, because the concentration of viruses in natural surface water are not generally above 104 pfu/L or 106 GCs/ L,18−23 the filter cartridge with EGM should be able to adequately concentrate viruses from large volumes of natural surface water (10−100 L). During this study, it was also found that samples processed from large volumes of water tended to cause inhibitory effects more frequently than those from smaller volumes. This indicates that some substances, for example, humic and fulvic acids from environmental samples, coconcentrated with the viruses caused detection inhibition.47,48 In addition, the beef extract used in one of the eluates contains high concentrations of poorly characterized components, which may interfere with qPCR and contribute to the inhibition of qPCR in detecting viruses.49 Three effective approaches were taken in this study to avoid these inhibitory elements. First, a two-step RT-qPCR format was used. It was observed that inhibition was a major problem for PV-1 detection in the river water, as described previously, but much less problematic for HAdV-41 detection.50,51 Therefore, we believe that the inhibition occurred during the RT phase (i.e., only used for PV-1). In addition, in the one-step RT-qPCR detection assay, it was found that inhibitors present in the extracted RNA significantly affected the fluorescent signal produced as the amplification curves were “jagged” even when the extracted RNA from the water samples was diluted 1:10. This phenomenon was not observed during the two-step RT-qPCR since the inhibitors had been diluted out during the qPCR step (SI Figure S11). Second, internal controls were incorporated in the assays to evaluate inhibition problems during qRT-PCR as previously done by other groups.3,50,52−54 By using internal controls, all nucleic acid extracts were amplified to verify the impact of inhibitors, both in undiluted and diluted form (up to 100-fold). Third, PEG precipitation following elution was used to remove partial inhibitors, as previously described.26,55 In conclusion, we have developed a new filter cartridge system with EGM for the recovery of dilute viruses from largevolumes of natural surface water samples. Not only have we shown high virus recovery from river, lake and reservoir water, but also describe a system without the need for pretreatments such as clarification. Due to the high efficiency of the virus concentration step, this new system should improve the detection rate of various viruses and has sufficient potential to be applied to the detection of viruses from natural surface water. It should also be effective for other types of freshwater, including tap, recreational and groundwater.
■
■
AUTHOR INFORMATION
Corresponding Author
*Phone: +86-22-84655345; fax: +86-22-23328809; e-mail:
[email protected]. Author Contributions †
M.J. and X.G. contributed equally to this work.
Notes
The authors declare no competing financial interest.
■
ACKNOWLEDGMENTS This study was supported by grants from the National Natural Science Foundation of China (81372947, 30930078, 81100100), National High Technology Research and Development Program of China (2009AA06Z404).
■
ABBREVIATIONS: T water temperature TC total coliforms TB total bacteria TTC thermotolerant coliforms NTU nephelometric turbidity unit
■
REFERENCES
(1) Bosch, A. Human enteric viruses in the water environment: a minireview. Int. Microbiol. 1998, 1 (3), 191−196. (2) Abbaszadegan, M. Advanced detection of viruses and protozoan parasites in water. Rev. Biol. Biotechnol. 2001, 1 (2), 21−26. (3) Wyn-Jones, A. P.; Carducci, A.; Cook, N.; D’Agostino, M.; Divizia, M.; Fleischer, J.; Gantzer, C.; Gawler, A.; Girones, R.; Holler, C.; de Roda Husman, A. M.; Kay, D.; Kozyra, I.; Lopez-Pila, J.; Muscillo, M.; Nascimento, M. S.; Papageorgiou, G.; Rutjes, S.; Sellwood, J.; Szewzyk, R.; Wyer, M. Surveillance of adenoviruses and noroviruses in European recreational waters. Water Res. 2011, 45 (3), 1025−1038. (4) Wong, M.; Kumar, L.; Jenkins, T. M.; Xagoraraki, I.; Phanikumar, M. S.; Rose, J. B. Evaluation of public health risks at recreational beaches in Lake Michigan via detection of enteric viruses and a human-specific bacteriological marker. Water Res. 2009, 43 (4), 1137− 1149. (5) Soller, J. A.; Bartrand, T.; Ashbolt, N. J.; Ravenscroft, J.; Wade, T. J. Estimating the primary etiologic agents in recreational freshwaters impacted by human sources of faecal contamination. Water Res. 2010, 44 (16), 4736−4747. (6) Sdiri-Loulizi, K.; Hassine, M.; Aouni, Z.; Gharbi-Khelifi, H.; Chouchane, S.; Sakly, N.; Neji-Guediche, M.; Pothier, P.; Aouni, M.; Ambert-Balay, K. Detection and molecular characterization of enteric viruses in environmental samples in Monastir, Tunisia between January 2003 and April 2007. J. Appl. Microbiol. 2010, 109 (3), 1093− 1104. (7) Steyer, A.; Torkar, K. G.; Gutierrez-Aguirre, I.; Poljsak-Prijatelj, M. High prevalence of enteric viruses in untreated individual drinking water sources and surface water in Slovenia. Int. J. Hyg Environ. Health. 2011, 214 (5), 392−398. (8) Ogorzaly, L.; Bertrand, I.; Paris, M.; Maul, A.; Gantzer, C. Occurrence, survival, and persistence of human adenoviruses and Fspecific RNA phages in raw groundwater. Appl. Environ. Microbiol. 2010, 76 (24), 8019−8025. (9) Miagostovich, M. P.; Ferreira, F. F.; Guimaraes, F. R.; Fumian, T. M.; Diniz-Mendes, L.; Luz, S. L.; Silva, L. A.; Leite, J. P. Molecular detection and characterization of gastroenteritis viruses occurring naturally in the stream waters of Manaus, central Amazonia, Brazil. Appl. Environ. Microbiol. 2008, 74 (2), 375−382.
ASSOCIATED CONTENT
S Supporting Information *
We present details for microorganisms and cell lines, quality of water samples, filter cartridge binding capacity, eluents constitute, concentration process of glass wool filter and a 1MDS filter, reaction condition of RT-qPCR assays and some results of interest mainly to specialists in the Supporting 6954
dx.doi.org/10.1021/es501415m | Environ. Sci. Technol. 2014, 48, 6947−6956
Environmental Science & Technology
Article
quantification of model viruses in water. Environ. Sci. Technol. 2012, 46 (18), 10073−10080. (28) Tian, P.; Yang, D.; Pan, L.; Mandrell, R. Application of a receptor-binding capture quantitative reverse transcription-PCR assay to concentrate human norovirus from sewage and to study the distribution and stability of the virus. Appl. Environ. Microbiol. 2012, 78 (2), 429−436. (29) Grassi, T.; Bagordo, F.; Idolo, A.; Lugoli, F.; Gabutti, G.; De Donno, A. Rotavirus detection in environmental water samples by tangential flow ultrafiltration and RT-nested PCR. Environ. Monit Assess. 2010, 164 (1−4), 199−205. (30) Gibson, K. E.; Schwab, K. J. Detection of bacterial indicators and human and bovine enteric viruses in surface water and groundwater sources potentially impacted by animal and human wastes in Lower Yakima Valley, Washington. Appl. Environ. Microbiol. 2011, 77 (1), 355−362. (31) Schultz, A. C.; Perelle, S.; Di Pasquale, S.; Kovac, K.; De Medici, D.; Fach, P.; Sommer, H. M.; Hoorfar, J. Collaborative validation of a rapid method for efficient virus concentration in bottled water. Int. J. Food Microbiol. 2011, 145 (Suppl 1), S158−166. (32) Strancar, A.; Podgornik, A.; Barut, M.; Necina, R. Short monolithic columns as stationary phases for biochromatography. Mod. Adv. Chromatogr. 2002, 49−85. (33) Francy, D. S.; Stelzer, E. A.; Brady, A. M.; Huitger, C.; Bushon, R. N.; Ip, H. S.; Ware, M. W.; Villegas, E. N.; Gallardo, V.; Lindquist, H. D. Comparison of filters for concentrating microbial indicators and pathogens in lake water samples. Appl. Environ. Microbiol. 2013, 79 (4), 1342−1352. (34) Lambertini, E.; Spencer, S. K.; Bertz, P. D.; Loge, F. J.; Kieke, B. A.; Borchardt, M. A. Concentration of enteroviruses, adenoviruses, and noroviruses from drinking water by use of glass wool filters. Appl. Environ. Microbiol. 2008, 74 (10), 2990−2996. (35) APHA. Standard Methods for the Examination of Water and Wastewater, 20th ed.; American Public Health Association: Washington, D. C., 1998. (36) Karim, M. R.; Rhodes, E. R.; Brinkman, N.; Wymer, L.; Fout, G. S. New electropositive filter for concentrating enteroviruses and noroviruses from large volumes of water. Appl. Environ. Microbiol. 2009, 75 (8), 2393−2399. (37) Wyn-Jones, A. P.; Sellwood, J. Enteric viruses in the aquatic environment. J. Appl. Microbiol. 2001, 91 (6), 945−962. (38) Payment, P.; Larose, Y.; Trudel, M. Polioviruses as indicator of virological quality of water. Can. J. Microbiol. 1979, 25 (10), 1212− 1214. (39) Skraber, S.; Gassilloud, B.; Schwartzbrod, L.; Gantzer, C. Survival of infectious Poliovirus-1 in river water compared to the persistence of somatic coliphages, thermotolerant coliforms and Poliovirus-1 genome. Water Res. 2004, 38 (12), 2927−2933. (40) Jin, M.; Shan, J.; Chen, Z.; Guo, X.; Shen, Z.; Qiu, Z.; Xue, B.; Wang, Y.; Zhu, D.; Wang, X.; Li, J. Chlorine dioxide inactivation of enterovirus 71 in water and its impact on genomic targets. Environ. Sci. Technol. 2013, 47 (9), 4590−4597. (41) Hornstra, L. M.; Smeets, P. W.; Medema, G. J. Inactivation of bacteriophage MS2 upon exposure to very low concentrations of chlorine dioxide. Water Res. 2011, 45 (4), 1847−1855. (42) Ouyang, Y.; Ma, H.; Jin, M.; Wang, X.; Wang, J.; Xu, L.; Lin, S.; Shen, Z.; Chen, Z.; Qiu, Z.; Gao, Z.; Peng, L.; Li, J. Etiology and epidemiology of viral diarrhea in children under the age of five hospitalized in Tianjin, China. Arch. Virol. 2012, 157 (5), 881−887. (43) Millen, H. T.; Gonnering, J. C.; Berg, R. K.; Spencer, S. K.; Jokela, W. E.; Pearce, J. M.; Borchardt, J. S.; Borchardt, M. A. Glass wool filters for concentrating waterborne viruses and agricultural zoonotic pathogens. J. Visualized Exp. 2012, 61, e3930. (44) Cashdollar, J. L.; Brinkman, N. E.; Griffin, S. M.; McMinn, B. R.; Rhodes, E. R.; Varughese, E. A.; Grimm, A. C.; Parshionikar, S. U.; Wymer, L.; Fout, G. S. Development and evaluation of EPA method 1615 for detection of enterovirus and norovirus in water. Appl. Environ. Microbiol. 2013, 79 (1), 215−223.
(10) Okoh, A. I.; Sibanda, T.; Gusha, S. S. Inadequately treated wastewater as a source of human enteric viruses in the environment. Int. J. Environ. Res. Public Health. 2010, 7 (6), 2620−2637. (11) Kiulia, N. M.; Netshikweta, R.; Page, N. A.; Van Zyl, W. B.; Kiraithe, M. M.; Nyachieo, A.; Mwenda, J. M.; Taylor, M. B. The detection of enteric viruses in selected urban and rural river water and sewage in Kenya, with special reference to rotaviruses. J. Appl. Microbiol. 2010, 109 (3), 818−828. (12) Katayama, H.; Shimasaki, A.; Ohgaki, S. Development of a virus concentration method and its application to detection of enterovirus and norwalk virus from coastal seawater. Appl. Environ. Microbiol. 2002, 68 (3), 1033−1039. (13) Connell, C.; Tong, H. I.; Wang, Z.; Allmann, E.; Lu, Y. New approaches for enhanced detection of enteroviruses from Hawaiian environmental waters. PLoS One. 2012, 7 (5), e32442. (14) Jothikumar, N.; Sobsey, M. D.; Cromeans, T. L. Development of an RNA extraction protocol for detection of waterborne viruses by reverse transcriptase quantitative PCR (RT-qPCR). J. Virol Methods. 2010, 169 (1), 8−12. (15) Pang, X. L.; Lee, B. E.; Pabbaraju, K.; Gabos, S.; Craik, S.; Payment, P.; Neumann, N. Pre-analytical and analytical procedures for the detection of enteric viruses and enterovirus in water samples. J. Virol Methods. 2012, 184 (1−2), 77−83. (16) McMinn, B. R.; Cashdollar, J. L.; Grimm, A. C.; Fout, G. S. Evaluation of the celite secondary concentration procedure and an alternate elution buffer for the recovery of enteric adenoviruses 40 and 41. J. Virol Methods. 2012, 179 (2), 423−428. (17) O’Toole, J.; Sinclair, M.; Malawaraarachchi, M.; Hamilton, A.; Barker, S. F.; Leder, K. Microbial quality assessment of household greywater. Water Res. 2012, 46 (13), 4301−4313. (18) Bosch, A.; Pinto, R. M.; Abad, F. X., Survival and transport of enteric viruses in the environment. In Viruses in Foods; Springer, 2006; pp 151−187. (19) de Roda Husman, A.; Penders, E.; Krom, A.; Bakker, G.; Hoogenboezem, W. Viruses in the Rhine and Source Waters for Drinking Water Production; RIWA, 2005. (20) Lodder, W. J.; de Roda Husman, A. M. Presence of noroviruses and other enteric viruses in sewage and surface waters in The Netherlands. Appl. Environ. Microbiol. 2005, 71 (3), 1453−1461. (21) Tani, N.; Shimamoto, K.; Ichimura, K.; Nishii, Y.; Tomita, S.; Oda, Y. Enteric virus levels in river water. Water Res. 1992, 26 (1), 45− 48. (22) Aslan, A.; Xagoraraki, I.; Simmons, F.; Rose, J.; Dorevitch, S. Occurrence of adenovirus and other enteric viruses in limited-contact freshwater recreational areas and bathing waters. J. Appl. Microbiol. 2011, 111 (5), 1250−1261. (23) Hundesa, A.; Maluquer de Motes, C.; Bofill-Mas, S.; AlbinanaGimenez, N.; Girones, R. Identification of human and animal adenoviruses and polyomaviruses for determination of sources of fecal contamination in the environment. Appl. Environ. Microbiol. 2006, 72 (12), 7886−7893. (24) Percival, S. L. e. a., Methods for the detection of waterborne viruses. In Microbiology of Waterborne Diseases: Microbiological Aspects and Risks; Percival, S. L., Chalmers, R., Embrey, M., Hunter, P. R., Sellwood, J., Wyn-Jones, P., Eds.; Academic Press Inc: London, U.K., 2004; p 349. (25) Ikner, L. A.; Soto-Beltran, M.; Bright, K. R. New method using a positively charged microporous filter and ultrafiltration for concentration of viruses from tap water. Appl. Environ. Microbiol. 2011, 77 (10), 3500−3506. (26) Deboosere, N.; Horm, S. V.; Pinon, A.; Gachet, J.; Coldefy, C.; Buchy, P.; Vialette, M. Development and validation of a concentration method for the detection of influenza a viruses from large volumes of surface water. Appl. Environ. Microbiol. 2011, 77 (11), 3802−3808. (27) Pei, L.; Rieger, M.; Lengger, S.; Ott, S.; Zawadsky, C.; Hartmann, N. M.; Selinka, H. C.; Tiehm, A.; Niessner, R.; Seidel, M. Combination of crossflow ultrafiltration, monolithic affinity filtration, and quantitative reverse transcriptase PCR for rapid concentration and 6955
dx.doi.org/10.1021/es501415m | Environ. Sci. Technol. 2014, 48, 6947−6956
Environmental Science & Technology
Article
(45) CHARLES, P. Applied and theoretical aspects of virus adsorption to surfaces. Adv. Appl. Microbiol. 1984, 30, 133. (46) Ikner, L. A.; Soto-Beltran, M.; Bright, K. R. New method using a positively charged microporous filter and ultrafiltration for concentration of viruses from tap water. Appl. Environ. Microbiol. 2011, 77 (10), 3500−3506. (47) Rådström, P. L. C.; Lövenklev, M.; Knutsson, R.; Wolffs, P. Strategies for overcoming PCR inhibition. CHC Protoc. 2008, DOI: 10.1101/pdb.top20. (48) Hata, A.; Katayama, H.; Kitajima, M.; Visvanathan, C.; Nol, C.; Furumai, H. Validation of internal controls for extraction and amplification of nucleic acids from enteric viruses in water samples. Appl. Environ. Microbiol. 2011, 77 (13), 4336−4343. (49) Schwab, K. J.; De Leon, R.; Sobsey, M. D. Concentration and purification of beef extract mock eluates from water samples for the detection of enteroviruses, hepatitis A virus, and Norwalk virus by reverse transcription-PCR. Appl. Environ. Microbiol. 1995, 61 (2), 531−537. (50) Ahmed, W.; Goonetilleke, A.; Gardner, T. Human and bovine adenoviruses for the detection of source-specific fecal pollution in coastal waters in Australia. Water Res. 2010, 44 (16), 4662−4673. (51) Hamza, I. A.; Jurzik, L.; Stang, A.; Sure, K.; Uberla, K.; Wilhelm, M. Detection of human viruses in rivers of a densly-populated area in Germany using a virus adsorption elution method optimized for PCR analyses. Water Res. 2009, 43 (10), 2657−2668. (52) Sauer, E. P.; Vandewalle, J. L.; Bootsma, M. J.; McLellan, S. L. Detection of the human specific Bacteroides genetic marker provides evidence of widespread sewage contamination of stormwater in the urban environment. Water Res. 2011, 45 (14), 4081−4091. (53) Hamza, I. A.; Jurzik, L.; Uberla, K.; Wilhelm, M. Evaluation of pepper mild mottle virus, human picobirnavirus and Torque teno virus as indicators of fecal contamination in river water. Water Res. 2011, 45 (3), 1358−1368. (54) Gibson, K. E.; Schwab, K. J.; Spencer, S. K.; Borchardt, M. A. Measuring and mitigating inhibition during quantitative real time PCR analysis of viral nucleic acid extracts from large-volume environmental water samples. Water Res. 2012, 46 (13), 4281−4291. (55) Borchardt, M. A.; Haas, N. L.; Hunt, R. J. Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions. Appl. Environ. Microbiol. 2004, 70 (10), 5937−5946. (56) Xagoraraki, I.; Kuo, D. H.; Wong, K.; Wong, M.; Rose, J. B. Occurrence of human adenoviruses at two recreational beaches of the great lakes. Appl. Environ. Microbiol. 2007, 73 (24), 7874−7881. (57) Kageyama, T.; Kojima, S.; Shinohara, M.; Uchida, K.; Fukushi, S.; Hoshino, F. B.; Takeda, N.; Katayama, K. Broadly reactive and highly sensitive assay for Norwalk-like viruses based on real-time quantitative reverse transcription-PCR. J. Clin. Microbiol. 2003, 41 (4), 1548−1557.
6956
dx.doi.org/10.1021/es501415m | Environ. Sci. Technol. 2014, 48, 6947−6956
