High-volume ultrafiltration: Going beyond indicator bacteria Kirs, - - PowerPoint PPT Presentation

High-volume ultrafiltration: Going beyond indicator bacteria

Kirs, M., Kearns, E. A., Castillo, S.M. , Lim, D. V., Fujioka, R.S

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

Why water quality matters?

Human Health - water-borne illnesses Environment - biodiversity loss and decline of ecosystem services

Hawaii Rules and Regulations

• Public (drinking) Water Systems (serve ≥ 15 connections or

≥ 25 individuals) HI DOH: HAR11:20, §11-20-6 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

Hawaii Rules and Regulations

• Recreational Waters: DOH: HAR11:54, §11-54-8

Recreational criteria for all State waters Within 30 days: Enterococci: GM ≤ 35 CFU 100ml-1 and STV 130 100ml-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)

Distribution of microorganisms is patchy

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

Sample # Total coliforms

• E. coli

Enterococci (5 min intervals) MPN/100ml MPN/100ml MPN/100ml 1 >24196 8164 5475 2 >24196 11199 4106 3 >24196 7270 3255 4 >24196 5794 2282 5 >24196 5794 4611 6 >24196 8664 4106 7 >24196 7701 2400 8 >24196 10462 2755 9 >24196 6488 2382 10 >24196 4352 3255 Arithmetic mean 7589 3463 Geometric mean 7317 3319 Standard deviation 2135 1079

Max 11199 5475 Min 4352 2282

Distribution of microorganisms is patchy in time

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

Tangential flow Dead-end flow

Permeate: light gray

Hollow fibers

Filte iltering ng sam ample le

Test fluid: dark gray with black particles that are too big to pass filter membrane

Recirculation

Filter membrane

Closed

Tangential flow Dead-end flow

Losing Buffer

Hollow fibers

Rec ecove

• very

Laminar recovery: flowing buffer in same direction as test fluid

Recirculation

Filter membrane

Closed

Backflush recovery: pushing buffer in direction

• pposite to test

fluid

Why Dead-end ultrafiltration (DEUF)

• Easier to setup
• Faster to filter
• Simpler to automate
• Consistent recovery (in HI: 363.2 ml (±13.9 ml))
• Concentrates as well as TFUF

Hawaii Study

Sewage Spike Beach Water Potable Water

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

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

Good agreement between estimates by both methods

Hawaii Study: All Data

Hawaii Study: Sewage spikes

• Concentrations comparable by both methods
• Enterococci, coliphages and human polyomaviruses were

detected using ultrafiltration method only

**

Hawaii Study: Coastal Samples

58.9% grab samples and 73.2 % ultrafiltration samples positive

• > Effective in retaining 28

nm sized particles

• > More representative

sample

Group Grab sample (%) Ultrafiltration sample (%) HPC 100 100 TC 100 100 ECOLI 86 100 ENT 57 100 CPERF 100 100 PHAGE 29 HBAC 29 43 HPYV 29

• > Effective in retaining 28 nm

sized particles

• > More representative

sample

• > Good water quality on

most beaches under ambient conditions

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

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
• vercome!

Take home message:

First instrument in Hawaii

Further projects

• Coastal environments
• Beach sand characterization
• (Source water characterization)

Utilized for: Pathogen detection, source specific markers, microbial community analyses

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.

Source tracking in Kahalu`u

Source tracking in Manoa watershed

Several lanes of evidence

Workshop with the CWB (DOH)

Acknowledgments

• 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
• Doak and Richard Cox Foundation
• State WRRIP/USGS 104B
• HI Department of Health