High-volume ultrafiltration: Going beyond indicator bacteria. Kirs, M., Kearns, E. A., Castillo, S.M., Lim, D. V., Fujioka, R.S

Transcription

1 High-volume ultrafiltration: Going beyond indicator bacteria Kirs, M., Kearns, E. A., Castillo, S.M., Lim, D. V., Fujioka, R.S

2 Outline Introduction Why water quality matters HI Rules and Regulations Issues with microbiological water quality measurements Solution: ultrafiltration device The device (PMACS) Evaluation in HI Conclusions and Future Directions

3 Why water quality matters? Human Health - water-borne illnesses Environment - biodiversity loss and decline of ecosystem services

4 Hawaii Rules and Regulations Public (drinking) Water Systems (serve 15 connections or 25 individuals) HI DOH: HAR11:20, Maximum Microbiological Contaminant Levels System is compliant when: 1) if n 40 samples per month, 5% of samples positive for total coliforms if n<40 samples per month, 1 sample positive for total coliforms 2) No fecal coliforms OR Escherichia coli

5 Hawaii Rules and Regulations Recreational Waters: DOH: HAR11:54, Recreational criteria for all State waters Within 30 days: Enterococci: GM 35 CFU 100ml -1 and STV ml -1 (10% of samples). Warning signs shall be posted at locations where human sewage has been identified as temporarily contributing to the enterococcus count. Enterococcus and C. perfringens 50 CFU 100ml -1 Roughly 4% or 7% samples exceed recreational water quality standards for enterococci in HI. HI ranked 7 out of 30 coastal states in US (NRDC, 2014)

6 Distribution of microorganisms is patchy Sources of pollutants (stream, sand, sediment, beach showers, swimmers, land runoff, etc.) Transport and dilution by tide and currents

7 Distribution of microorganisms is patchy in time Sample # Total coliforms E. coli Enterococci (5 min intervals) MPN/100ml MPN/100ml MPN/100ml 1 > > > > > > > > > > Arithmetic mean Geometric mean Standard deviation Max Min

8 Portable Multi-use Automated Concentration System (PMACS) (developed in the laboratory of Dr. Daniel Lim, University of South Florida) Dead-end ultrafiltration device Automated Hollow fiber filter cartridges 30 kda >100 L!!! Light and portable Recovery module Collection module

9 Tangential flow Filtering sample Dead-end flow Closed Recirculation Hollow fibers Filter membrane Permeate: light gray Test fluid: dark gray with black particles that are too big to pass filter membrane

10 Tangential flow Recovery Dead-end flow Closed Recirculation Hollow fibers Filter membrane Losing Buffer Laminar recovery: flowing buffer in same direction as test fluid Backflush recovery: pushing buffer in direction opposite to test fluid

11 Why Dead-end ultrafiltration (DEUF) Easier to setup Faster to filter Simpler to automate Consistent recovery (in HI: ml (±13.9 ml)) Concentrates as well as TFUF

12 Hawaii Study Sewage Spike Beach Water Potable Water

13 Hawaii Study: Parameters Fecal Indicator Bacteria (FIB): HPC, total coliforms, E. coli, enterococci, F + specific coliphage, C. perfringens Source specific markers: human Bacteroides, human polyomaviruses

14 Hawaii Study Teams Clean Water Branch, Hawaii Department of Health City and County of Honolulu WRRC, University of Hawaii Dr. Daniel Lim Laboratory, University of South Florida

15 Hawaii Study: All Data Good agreement between estimates by both methods

16 Hawaii Study: Sewage spikes ** Concentrations comparable by both methods Enterococci, coliphages and human polyomaviruses were detected using ultrafiltration method only

17 Hawaii Study: Coastal Samples Group Grab sample (%) HPC TC ECOLI ENT CPERF PHAGE 0 29 HBAC HPYV 0 29 Ultrafiltration sample (%) 58.9% grab samples and 73.2 % ultrafiltration samples positive -> Effective in retaining 28 nm sized particles -> More representative sample

18 -> Effective in retaining 28 nm sized particles -> More representative sample -> Good water quality on most beaches under ambient conditions

19 Hawaii Study: Potable water Concentration of E. coli in two Honolulu source water samples analyzed was <0.001 MPN /100 ml (standard is <1MPN/100ml) No human specific markers Excellent microbiological source water quality

20 Take home message: Use wisely! Pros: Provides representative sample Excellent for detection of rare targets such as human pathogens Can pick up 28 nm sized viral particles without prior treatment Fully automated (consistent and little room for operator error) Cost effective Cons: Labor and time intensive <- but it has different purpose! PCR inhibitors can be a challenge for molecular tests <- but can overcome! First instrument in Hawaii

21 Further projects Coastal environments Beach sand characterization (Source water characterization) Utilized for: Pathogen detection, source specific markers, microbial community analyses

22 Source tracking in Kahalu`u Geometric mean of enterococci, C. perfringens and coliphages concentrations (from top down respectively) at each site (10 sites). Red, pink and green indicates human-associated Bacteroides, human polyomavirus and human adenoviruses as presence (+) in the samples collected (n=4 at each site, all samples were tested). Percent of samples exceeding the enterococci based STV (130 cfu 100ml -1 AND C. perfringens concentrations of 50 CFU 100 ml -1 at each site are also indicated.

23 Source tracking in Manoa watershed

24 Several lanes of evidence

25 Workshop with the CWB (DOH)

26 Acknowledgments Doak and Richard Cox Foundation State WRRIP/USGS 104B HI Department of Health Dr. Valerie J. Harwood (USF) Mr. Owen Narikawa, Board of Water Supply Mr. Watson Okubo, CWB, Department of Health Mr. Ken Tenno, Lab. Branch, CCH