Transcript POU/POE Devices as Final Barriers

POU/POE Devices as
Final Barriers
Joseph F. Harrison, P.E., CWS-VI
Technical Director
Water Quality Association
[email protected]
Barriers against Contaminants in
Water
Sanitary Survey
Source Water Management
Central Water Treatment
Pretreatment
Filtration
Disinfection
Distribution System Management
and
POE/POU Devices in Homes?
Why the Final Barrier?
Product Usage Habits
68%
Use bottled water
28%
Have any type of water filtration product installed in the home
23%
Have a refrigerator with water filter
Boil tap water
Have a water softener intalled in the home
Other (n=196)
None of the above
Have a Brita-filter
Pitcher with filter
Use tap water
%
28%
23%
19%
12%
Other
11%
9%
10%
0% 10% 20% 30% 40% 50% 60% 70% 80%
Percentages do not add to 100% because of multiple response
POU/POE as a Final Barrier
 Aesthetic Concerns
 Treatment Effects
• DBP Levels
• Process Changes, Lead & Copper Levels
 Distribution Related Effects
• Corrosion Products
• Microbial Intrusions
• Endemic Diseases
• Security Issues
 MCL Vs MCLG
POU/POE Technologies
POU & POE technologies –mostly
miniaturized versions of central treatment
Several different technologies usually
available for the treatment of any
contaminant
Many small & large companies involved in
POU and POE water treatment
Standards & Certification programs
provide higher level of confidence and
credibility now than in prior years
History of POU and POE
Products
Aesthetic enhancement – historical
Slow evolution to health related
claims
ANSI/NSF Standards in 1980’s
ANSI accredited testing and
certification – NSF, UL, WQA
State certifications – IA, WI, CA
Automatic water quality monitors
and end of life indicators– 1990’s
NSF/ANSI American
National Standards
Std. 42: Aesthetic Effects
Std. 44: POE softeners – Hardness,
Barium, Radium
Std. 53: Health effects – Lead, Cysts,
TTHM, VOC, MTBE, Arsenic, etc,
Std. 55: Ultraviolet light (UV) – POE &
POU Class A & B
Std. 58: Reverse Osmosis Systems
Std. 62: Distillers
All: Structural Integrity, Material Safety,
Treatment Performance, and Approval of
Labeling and Literature
Today’s Manufacturers and
Product Variations
70+ manufacturers, large and small
Product types: pitchers, faucet attached,
under sink, counter top, whole-house
State-of-the-Art Technologies: Carbon
Block, Fine Filters, Specialty Media, RO,
UV, Ozone, Distillation
Capacities: 35 to over 100,000 gallons
@1 to 20 gallons per min
Types of Products
Personal water bottle
Pour through pitcher
Countertop Units connected to sink faucet
Faucet attached filters
Plumbed-in units
Plumbed-in units with separate faucet
Shower Filters
Whole-house water treatment Devices
(POE)
Contaminants Reduced by
these Devices
Particulates
Inorganics
Radium & Other Radionuclides
Volatile Organic Chemicals
Synthetic Organic Chemicals
Microbials
INORGANICS
POU/POE Technologies for
Inorganics
Water Softener – Barium & Radium Only
Media Filters – Arsenic, Asbestos, Lead, &
Mercury
RO – All Inorganics
Distillers – All Inorganics (Except for
Asbestos, Radium, & Nitrites not covered
presently in Std 62)
POU Reverse Osmosis systems
and Filters
Inorganics Included in
NSF/ANSI Standards
Arsenic, Asbestos, Barium,
Cadmium, Copper, Fluoride,
Chromium (Hexavalent &
Trivalent), Lead, Mercury, Nitrite &
Nitrate, Perchlorate, Radium
226/228, Selenium
Lead Level Survey for
Systems>50K (USEPA 2000-2004)
Range of Lead
(90th%),ppb
0-5
Number of Samples
6-15
443
16-25
27
26-50
12
50-200
6
936
POU & POE Products Certified for
Inorganic Reduction
Type
Softeners (POE)
Media Filters
VOCs & SOCs
Asbestos
Lead
Mercury
# of Companies
15
# of Products
282
32
16
34
14
160
158
163
64
RO Units for most
Inorganics
31
119
Distillers(Plumbed)
3
24
Figure 6: Arsenic V Reduction
TM
Plymouth Products, Inc. Granular Ferric Hydroxide
- GFH
Total Arsenic Concentration vs. Gallons of Water at pH = 8.5
100
Feed, Total As
EBCT = 10.6 sec.
Unit #1, Total As
Arsenic Concentration (ug/l)
Unit #2, Total As
10 ppb Line
75
50
25
0
0
75
150
225
300
375
450
525
600
Gallons of Water with a 50/50 Cycle at 0.60gpm
#01211-1
675
750
825
RADIONUCLIDES
Radium Reduction By Ion
Exchange
Relative affinity of ions for cation resins:
Radium
13.0
Barium
5.8
Calcium
1.9
Magnesium 1.67
Sodium
1.0
Radium & Barium Reduction
33 Water Softeners made by 3 companies have
been certified for such reduction by Certifiers
A steady state of operation is achieved for
Radium sorption when a Softener is operated in
normal fashion
Radium never breaks through before Hardness
in all of the experiments conducted by Dennis
Clifford and his coworkers. This has also been
substantiated by Vern Snoeyink’s work at
University of Illinois
POE Water Softeners
POU Products For Radionuclides
Reduction
POU RO & POU IE recognized by EPA as
Available Compliance Technologies for Small
Systems for the Reduction of Radium and many
other Radionuclides
Many POU RO have been certified for Radium
Reduction (147 products by 33 companies)
Some POU products have been certified for
Radon reduction
No Known POU IE Products currently in the
Market. Also No Protocol in Std 53 or Std 44
No Protocol for other Radionuclides in any of the
Standards at this time
ORGANICS
Disinfection Byproducts
Range of DBPs in Large Surface
Water Plants (USEPA 2000)
Contaminant
Range of plant Means
(µg/L)
TTHM
0 -177
HAA5
0 - 104
TOX
0 - 305
TTHM & HAA5 Levels in Small
Plants (USEPA 2001)
Contaminant
Range of Plant Means
(µg/L)
TTHM
0-328
HAA5
0-262
Volatile Organics
 EPA’s limitation is to use only POE for VOC
Reduction from a compliance point of view due to
concerns about dermal and inhalation related
risks
 There are no POE unit however tested and
certified for VOC Reduction by any of the testing
and certification organizations at this time
 Use of Certified POU units while not fully
protective, does reduce at least that portion of
the risk associated with consumption
Synthetic Organics Reductions
Included in Standard 53
 Chloroform Reduction has been substantiated
as a surrogate for these synthetic organics:
Alachlor, Atrazine, Carbofuron, 2,4-D,
Dibromochloropropane, Dinoseb, Endrin,
Ethylene Dibromide, Heptachlor, Heptachlor
Epoxide, Hexachlorocyclopentadiene, Lindane,
Methoxychlor, Pentachlorophenol, Simazine,
2,4,5-TP (Silvex) --Plus 34 other Volatile
Organic Chemicals (VOCs)
 The following can be tested by themselves
separately: Chlordane, PCBs, Toxaphene
Products Certified for Organics
For such VOC & SOC Reduction
Claims:
25 companies and 115 POU
products
For Chlordane, PCBs, & Toxaphene
Reduction Claims:
7 companies and 45 POU
products
Surrogate Testing With
Chloroform
 300 ppb chloroform in the influent water to be
reduced to below 15 ppb in the effluent water
during the entire test.
 A unit with an end of life indicator is tested to
remove contaminants for 120% of its claimed
life.
 A unit without an end of life indicator is tested
to remove contaminants for 200% of its
claimed life.
 An example of an actual test of a unit with a
claimed life of 500 gal with a shut off device is
shown here next:
Actual
Life
Test
Chloroform surrogate VOC reduction for 500 gallons
allowed claim
300
200
Influent
100
Effluent
Gallons Treated
600
550
500
450
400
350
300
250
200
150
100
50
0
0
Concentration (ppb)
400
MICROBIOLOGICAL
CONTAMINANTS
Estimate of number of cases of AGI
in USA attributable to Drinking
Water
By Colford et al, J. Water & Health 4, Suppl 02, 2006 (Based on studies
funded by CDC & USEPA)
 With an assumption of 90% risk being associated with source water
contamination or inadequate treatment
ESTIMATED NUMBER – 4.26 to 11.69 million per year
 With an assumption of 90% risk being associated with
contamination in the distribution system
ESTIMATED NUMBER – 10.87 to 11.69 million per year
Microbiological Purification
New Comprehensive ANSI/NSF Standard for all
Microbial Issues in Development
Cyst Reduction Covered in Std 53
Std 55 & Std 62 Cover Specific Aspects of
Microbial Issues
Std 55 recently updated using MS2 as a
surrogate for validation of UV Units
Std 62 uses B.subtiles as a surrogate to
validate the capability of a distiller
EPA Guide Standard & Protocol
Drafted in 1987. Covers Halogenated Resin, UV,
and Ceramic Filters. Has become the reference
Guide in this area
Uses Raoultella terrigena, a mixture of polio
& simian rota viruses, and Giardia (Crypto) Cysts
as Test Organisms
Requires reduction of 6 logs of bacteria, 4 logs
of viruses, and 3 logs of cysts under a set of
operating conditions of water quality and
sequence of cycles and sampling
Standard 55 – UV Units
Uses MS2 Bacteriophage and Verifies the UV
Dose at the set point to be no less than 40
mJ/sqcm for Class A Performance. Requires the
use of UV Sensors for sounding an alarm when
not effective
This Dose level has been universally accepted as
capable of yielding more than 4 log Inactivation
of Viruses (except adeno), 6 logs of bacteria,
and 3 logs of Crypto & Giardia
Units certified for Class B are to be offered only
for Aesthetic Improvement
UV Units Certified by NSF Intl
17 POE products made by 5 companies
have been listed as of now.
3 POU Products by one company carry
such certification
Certified POE Products have been verified
to be operable at flow rates ranging from
8 to 18 gpm, appropriate for single home
point of entry applications
Purifier Protocol Testing
Outside the Standard Related Activity, NSF and
many Universities such as U of AZ and U of S FL
offer Performance Tests using the Guide
Protocol as the general Basis
Shown are the Actual Data from tests done by
U of AZ on a POU Distiller Product & a POU UV
Product
Purifier Test Data- Distiller
 BACTERIA
>99.9999
E.coli, S.typhimurium,
S.dysentariae, C.jejuni,
Y.enterocolitica,
V.cholerae, M.fortutium,
R.terrigena
 VIRUSES
HAV, Adeno type2, Polio,
Simian rota
 CRYPTO
>99.9999
>99.99
>99.9
Purifier Test Data- UV UNIT
BACTERIA
E.coli, S.typhimurium,
S.dysentariae,
V.cholerae,
R.terrigena
VIRUSES
Polio & simian rota
CRYPTO & GIARDIA
>99.9999
>99.999
>99.9
Newer Microbial Devices
POE Ultrafiltration units
POU RO Systems with/without added
Microbial filters
Combination Filter systems with Microbial
filters
MCL Vs MCLG
MCL, MCLG, TT
 Maximum Contaminant Level (MCL) - The highest level of a
contaminant that is allowed in drinking water. MCLs are set as close
to MCLGs as feasible using the best available treatment technology
and taking cost into consideration. MCLs are enforceable standards.
 Maximum Contaminant Level Goal (MCLG) - The level of a
contaminant in drinking water below which there is no known or
expected risk to health. MCLGs allow for a margin of safety and are
non-enforceable public health goals
 Treatment Technique - A required process intended to reduce the
level of a contaminant in drinking water.
MCL Vs MCLG (Microorganisms)
Contaminant
MCLG
MCL or TT
Crypto
Zero
TT – 99%
Giardia
Zero
TT – 99.9%
Legionella
Zero
TT
Coliforms (incl
E.Coli &Fecal C)
Viruses
Zero
5%*
Zero
TT- 99.99%
MCL Vs MCLG (Disinfection
Byproducts)
Contaminant
MCLG (mg/L)
MCL (mg/L)
Bromate
Zero
0.010
Chlorite
0.8
1.0
Haloacetic Acids
(HAA5)
---*
Some Individual Ones
have MCLG values
0.060
Total Trihalomethanes
(TTHM)
---*
Some Individual Ones
have MCLG values
0.080
MCL Vs MCLG (Inorganics)
Contaminant
MCLG (mg/L)
MCL (mg/L)
Arsenic
Zero
0.010
Copper
1.3
Lead
Zero
TT (Action
Level=1.3)
TT (Action
Level=0.015)
0.002
Thallium
0.0005
MCL Vs MCLG (Organics)
Contaminant
Acrylamide
Alachlor
Benzene
PAHs
Carbon tetrachloride
Chlordane
DBCP
1,2 Dichloroethane
MCLG (mg/L)
MCL (mg/L)
Zero
TT(0.05%dose)
Zero
0.002
Zero
0.005
Zero
0.0002
Zero
0.005
Zero
0.002
Zero
0.0002
Zero
0.005
MCL Vs MCLG (Organics) Cont.
Contaminant
Dichloromethane
1,2-Dichloropropane
Di(2-ethylhexyl)phthalate
Dioxin
Epichlorohydrin
Ethylenedibromide
Heptachlor
Heptachlorepoxide
MCLG (mg/L)
Zero
Zero
Zero
Zero
Zero
Zero
Zero
Zero
MCL (mg/L)
0.005
0.005
0.006
0.00000003
TT(0.01%Dose)
0.00005
0.0004
0.0002
MCL Vs MCLG (Organics) Cont.
Contaminant
Hexachlorobenzene
PCBs
Pentochlorophenol
Tetrachloroethylene
Toxaphene
1,1,2-Trichloroethane
Trichloroethylene
Vinylchloride
MCLG (mg/L)
Zero
Zero
Zero
Zero
Zero
0.003
Zero
Zero
MCL (mg/L)
0.001
0.0005
0.001
0.005
0.003
0.005
0.005
0.002
MCL Vs MCLG (Radionuclides)
Contaminant
MCLG
MCL
Alpha Particles
Zero
15 pCi/L
Beta Particles &
photon emitters
Zero
4 millirems/year
Radium 226 &
Radium 228
Uranium
Zero
5 pCi/L
Zero
30 µg/L
Needs in this Area
Actual Tests showing the reduction from
MCL to MCLG for different contaminants
Protocols for use by certifiers
Incorporation into present ANSI/NSF
standards or development of new
Standards
Examples of POU/POE as Final
Barriers
Carbon Block Filter
Assumption: Tested & Certified for lead, cyst,
and VOC reduction
Barrier to synthetic & volatile organics, lead, and
protozoan cysts AND a partial barrier to bacteria
and viruses even though not claimed
Not a barrier to most other inorganics or
radionuclides
RO System with Carbon Filter
Assumption: Tested & Certified for reduction of
several Inorganics, Radionuclides, Cysts, and
VOC
Barrier to all tested inorganics, radionuclides,
protozoan cysts, many synthetic and volatile
organics. Also a probable barrier to several other
inorganics, bacteria, and viruses
Not a proven barrier against all microbials and
some organics
POE UV System
Assumption; Tested and certified as a
purifier under ANSI/NSF std 55
Barrier to all pathogenic bacteria, viruses,
and protozoan cysts
Not a barrier to organics, inorganics,
radionuclides, and particulates
POE Softener
Assumption: Tested for hardness reduction as
well as tested and certified for Radium and
Barrium reduction
Barrier to Radium & Barium as well as to soluble
lead, copper and other divalent cations
Not a barrier to most other contaminants
WATER SOFTENER IN
REGENERATION CYCLES
Examples of Commonly Used
Combinations
GAC filter, fine filter(with lead reducing media)
Carbon block, Arsenic removal media, microbial
Filter
RO, carbon block, UV/Microbial Filter
Distiller, carbon filter
Other Technologies
POE Aeration for Radon and other
Volatiles
POE Anion Exchange for Nitrate & Arsenic
Reduction
MTBE Reduction at POU & POE
POE Ozonation for Microbials
POE Fine Filtration for Microbials
POE Halogenated Resin for Microbials
POU/POE as a Final Barrier
 Aesthetic Concerns
 Treatment Effects
• DBP Levels
• Process Changes, Lead & Copper Levels
 Distribution Related Effects
• Corrosion Products
• Microbial Intrusions
• Endemic Diseases
• Security Issues
 MCL Vs MCLG