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© 2016 Water Research Foundation. ALL RIGHTS RESERVED.© 2015 Water Research Foundation. ALL RIGHTS RESERVED. No part of this presentation may be copied, reproduced, or otherwise utilized without permission.

WRF Webcast

Treatment Mitigation Strategies for

Poly-and Perfluoroalkyl Chemicals

June 2, 2016

© 2016 Water Research Foundation. ALL RIGHTS RESERVED.© 2016 Water Research Foundation. ALL RIGHTS RESERVED.

Water Research Foundation #4322

WRF Project Manager:

Alice Fulmer, Senior Research Mgr.

Principal Investigators:

Eric Dickenson, PhD (PI)

Chris Higgins, PhD (Co-PI)

Project Advisory Committee:

Joseph Lin, CH2M

Benjamin Stanford, Hazen and Sawyer

Michelle Hladik, USGS

Orren Schneider, American Water

© 2016 Water Research Foundation. ALL RIGHTS RESERVED.

Outline

• Objective

• Background

—Sources, PFAS, toxicology, health advisories,

UCMR3

• Approach and Method

• Results

—Full-Scale, Bench-Scale

• Conclusions


Objective

• Evaluate the ability of a wide spectrum

of full-scale water treatment techniques

to remove poly- and perfluoroalkyl

substances (PFASs) from raw water or

potable reuse sources.


Why should we care?

• The carbon-fluorine bond is the shortest

and strongest chemical bond in nature

—Chemical properties are less predictable

• Poly- and perfluoroalkyl substances

(PFASs) used in a wide variety of products

—Somewhat ubiquitous* in the environment

• Some PFASs persist indefinitely and are

difficult to remove from water


Sources and ConcernsSources

• In production since 1940s

• Found in aqueous film forming foam (AFFF)

to fight fuel fires, food wrapping,

microwave popcorn bags, clothing and

carpet protection products

• Used to make Teflon® and other high-

performance materials

Concerns

• Environmentally-persistent, bioaccumulative, and water soluble

• Found in human serum and wildlife


• Buck et al. 2011, Integrated Environmental Assessment and

Management, 7:4:513–541

• “perfluorinated chemical”, “perfluorochemical” = PFC

• PFC = perfluorocarbons, a family of greenhouse gases

• Poly- and perfluoroalkyl substances = PFASs

• Perfluoroalkyl acids = PFAAs (a subclass of PFASs)

Terminology and Acronyms

F F

F F

F F

F F

F F

F FF

F

FOH

O

Perfluoroalkyl acid Polyfluoroalkyl substance


Perfluorocarboxylic Acid

Perfluorosulfonic Acid

perfluorooctanoate - PFOA

perfluorooctane sulfonate - PFOS

Both PFAAs illustrated as deprotonated forms (i.e., carboxylate and sulfonate)

Perfluoroalkyl Acids (PFAAs)


Fluorocarbon tail – HYDROPHOBIC and OLEOPHOBIC

Sulfonate headgroup - HYDROPHILIC

NEGATIVE at

neutral pH

Perfluoroalkyl Acids (PFAAs)

Multiple fluorocarbon chainlengths


PFAA Formation from PFASs

O

F S

F

F

F

F O

N O

O7

N-EtFOSEpolymer

O

F S

F

F

F

F O

O-

O

F S

F

F

F

F O

N

O

O-

O

F S

F

F

F

F O

N OH

O

F S

F

F

F

F O

NH2

7

7

7

7

FOSA

PFOS

N-EtFOSE

N-EtFOSAA

O

F C

F

F

F

F O-

F

F

F

F

F

H

H

H

H

OH

F

F

F

F

F

H

H

H

H

OO

F

F

F

F

F

H

H

O-

O

7

7

7

O

F C

F

F

F

F O-6 7

PFOA PFNA

8:2 FTOHpolymer

8:2 FTOH

8:2 FTCA


Formation during Wastewater Treatment

mg/day flow in a typical wastewater treatment plant.

Mass out = ~2 x Mass in

Reprinted with permission from Schultz, M., Higgins, C., Huset, C., Luthy, R., Barofsky, D., Field, J., Fluorochemical Mass Flow in a

Municipal Wastewater Treatment Facility, Environmental Science & Technology, 40(23), 7350-7357. Copyright (2006) American

Chemical Society.


PFASs in Groundwater at

AFFF-Impacted Sites

• No AFFF-impacted site

has just one class of PFAS

• PFAAs not always the

most abundant

• To date, all AFFF-

impacted sites exceed

EPA HALs

• To date, highest levels:

— PFOS: 1,000,000 ng/L

— PFOA: 6,600,000 ng/L

Carboxylates Sulfonates Other PFASs

J. Field (Oregon State University). ESTCP Project 15 T2-045. Used by permission.


Human Exposure to PFASs

Landfillleachate (<10,000 ng/L)1

Adapted from Oliaei 2013, Environ Pollut Res1Allred et al. 2014 J Chrom;2 Schultz et al. 2006; Higgins ES&T 20053Schultz et al. 2006 a&b ES&T; 4Ahrens et al. Chemosphere 2015

• Inhalation• ingestion (dust/fibre)

ma

nu

factu

rer

wa

ste

liquids

breast milk

Biosolids

(<3,000 ng/g)2

Effluents

(<100 ng/L)3

solids

AFFF-impacted

groundwater = up to mg/L

wa

ste

wa

ter

tre

atm

en

tAFFF

AFFF-impacted surface water ~ 100s ng/L4

cord blood

goods

J. Field (Oregon State University). ESTCP Project 15 T2-045. Used by permission.


Toxicology• Non-cancer effects on liver and kidney1,2

— USEPA reference doses for PFOA and PFOS (non-cancer hazard only)▪ PFOS: 0.00002 mg/kg*day (reduced birth weight)

▪ PFOA: 0.00002 mg/kg*day (developmental effects in bones, accelerated puberty)

• Immunotoxicity potential3,4

• Potential carcinogenic/mutagenic properties5

— “Suggestive” for both (EPA) and “Possibly” for PFOA International

Agency for Research on Cancer

— Cancer Slope Factor for PFOA: 0.07 (mg/kg*day)-1

▪ Risk-based drinking water threshold for cancer endpoint higher (less conservative)

than non-cancer endpoint

• Other PFASs— Very limited information available in peer-reviewed literature and

chemical registration information (REACH dossiers, TSCA submittals)

1 Lau, Clinical and Environmental Toxicology, Experientia Supplementum 101. 20122 ATSDR, Draft Toxicological Profile for Perfluoroalkyls. 2015.3 Grandjean et al., JAMA. 2012.4 Granum et al., J Immunotox. 2013.5 USEPA. Drinking Water Health Advisories for PFOA and PFOS. 2016.

J. Conder (Geosyntec Consultants). ESTCP Project 15 T2-045. Used by permission.


EPA Health Advisories

On May 19, 2016, the U.S. EPA released its final health advisory levels for

PFOS and PFOA in drinking water

• “EPA's health advisories are non-enforceable and non-regulatory and

provide technical information to states agencies and other public health

officials on health effects, analytical methodologies, and treatment

technologies associated with drinking water contamination.”

EPA Fact Sheet on PFOA & PFOS Drinking Water Health Advisories, May 2016

https://www.epa.gov/ground-water-and-drinking-water/drinking-water-health-advisories-pfoa-and-pfos

PFAADrinking Water Health

Advisory Level

PFOA 70 ng/L

PFOS 70 ng/L

PFOA + PFOS 70 ng/L


What PWSs should do*

Steps to Assess Contamination

— “If water sampling results confirm that drinking water contains PFOA

and PFOS at individual or combined concentrations greater than 70

parts per trillion, water systems should quickly undertake additional

sampling to assess the level, scope and localized source of

contamination to inform next steps”

Steps to Inform

— “If water sampling results confirm that drinking water contains PFOA

and PFOS at individual or combined concentrations greater than 70

parts per trillion, water systems should promptly notify their State

drinking water safety agency (or with EPA in jurisdictions for which

EPA is the primary drinking water safety agency) and consult with the

relevant agency on the best approach to conduct additional sampling”

*According to the EPA Fact Sheet on PFOA & PFOS Drinking Water Health Advisories, May 2016


What PWSs should do (cont).

Steps to Limit Exposure

— “A number of options are available to drinking water systems to lower

concentrations of PFOA and PFOS in their drinking water supply. In

some cases, drinking water systems can reduce concentrations of

perfluoraklyl substances, including PFOA and PFOS, by closing

contaminated wells or changing rates of blending of water sources.

Alternatively, public water systems can treat source water with

activated carbon or high pressure membrane systems (e.g., reverse

osmosis) to remove PFOA and PFOS from drinking water. These

treatment systems are used by some public water systems today, but

should be carefully designed and maintained to ensure that they are

effective for treating PFOA and PFOS. In some communities, entities

have provided bottled water to consumers while steps to reduce or

remove PFOA or PFOS from drinking water or to establish a new

water supply are completed.”



What have States been doing?

Currently unclear if States will alter guideline values in

response to new EPA HALs

State

Guideline Value

for PFOS (ng/L)

Guideline Value

for PFOA (ng/L)

Delaware 200 400

Maine -- 100

Michigan 11 420

Minnesota 300 300

New Jersey -- 40

North Carolina -- 2000

Vermont -- 20



UCMR 3 Data

• EPA survey of all PWSs serving 10,000+

— 800 small PWSs also included

• PFAAs monitored: PFBS, PFHxS, PFOS, PFHpA, PFOA, PFNA

• Through 2015, 193 PWSs (3.9%) had detectable* PFAAs*Note “high” MRLs: PFOS MRL + PFOA MRL = 60 ng/L vs. HAL (combined) of 70 ng/L

Image and data courtesy of Xindi Hu (HSPH; Hu et al., in preparation)

Hydrologic unit codes (HUCs)

used as a proxy for watersheds


Objective

• Evaluate the ability of a wide spectrum

of full-scale water treatment techniques

to remove PFASs from raw water or

potable reuse sources.


Compounds Inclusion in

This Study

Inclusion

in CCL3

Inclusion

in UCMR3

State-Level

Guideline Values

Perfluoro Carboxylic Acids

Perfluorobutyric acid (PFBA) (MN)

Perfluoropentanoic acid (PFPnA)

Perfluorohexanoic acid (PFHxA)

Perfluoroheptanoic acid (PFHpA)

Perfluorooctanoic acid (PFOA) (MN,NJ)

Perfluorononanoic acid (PFNA)

Perfluorodecanoic acid (PFDA)

Perfluoroundecanoic acid (PFUnA)

Perfluorododecanoic acid (PFDoA)

Perfluoro Sulfonic Acids

Perfluorobutane sulfonic acid (PFBS)

Perfluorohexane sulfonic acid (PFHxS)

Perfluorooctane sulfonic acid (PFOS) (MN)

Perfluorodecane sulfonic acid (PFDS)

Approach: PFAAs


PFAS Classes Chemical Name Abbreviation # of Carbons

M.W.

(g/mol)

Perfluorobutyric acid PFBA 4 214

Perfluoropentanoic acid PFPeA 5 264

Perfluorohexanoic acid PFHxA 6 314

Perfluoroheptanoic acid PFHpA 7 364

Perfluorooctanoic acid PFOA 8 414

Perfluorononanoic acid PFNA 9 464

Perfluorodecanoic acid PFDA 10 514

Perfluoroundecanoic acid PFUnA 11 564

Perfluorododecanoic acid PFDoA 12 614

Perfluorobutane sulfonic acid PFBS 4 300

Perfluorohexane sulfonic acid PFHxS 6 400

Perfluorooctane sulfonic acid PFOS 8 500

Perfluorodecane sulfonic acid PFDS 10 600

Perfluorocarboxylic Acids

(PFCAs)

Perfluorosulfonic Acids

(PFSAs)

Other PFASs: perfluorooctane sulfonamide (FOSA), 2 perfluorosulfonamidoacetic acids,

4 fluorotelomer unsaturated carboxylic acids and 3 fluorotelomer sulfonic acids

Approach: PFASs


• Automated Solid-Phase Extraction -Dionex AutoTrace 280 workstation

• Isotopic Dilution LC/MS-MS - API 4000™

• Minimum Reporting Levels (MRLs): range from 0.1 to 5.0 ng/L

Analytical Methods


Utility

ID

State Source

Water

Treatment Train Source Water

Sampling Dates

Treatment Train

Sampling Dates

1 WI SW 8/9/2011

2 OK SW 8/23/2011

3 AK SW 8/22/2011

4 CA 2º TWW MF/RO/UV‐AOP/DI/Cl2 8/8/2011 12/6/2011, 2/22/2012

5 AL SW AIX/COAG/FLOC/SED/MF/Cl2 8/15/2011 12/13/2011, 3/20/2012

6 CO SW 4/9/2012

7 CO SW RBF/ARR/SOFT/SCC/UV-AOP/G-FIL(Biological)/GAC 9/13/2011

5/1/2012, 6/19/2012,

8/21/2012

8 OH SW SED/COAG/FLOC/SED/G-FIL/GAC/Cl2 8/9/2011 12/12/2011, 2/22/2012

9 NV SW 9/19/2011

10 CA 3º TWW MF/UF/RO/UV-AOP 10/4/2011 1/9/2012, 3/6/2012

11 NJ SW/GW AER/COAG/FLOC/SED/G-FIL/ClO2 12/6/2011, 3/14/2012

12 NJ SW O3/DAF/Cl2/CLM 3/21/2012, 5/23/2012

13 NJ GW UV/Cl2 3/21/2012, 5/23/2012

14 NJ GW AIX/APT/Cl2 5/30/2012, 9/19/2012

15 NJ GW Cl2/MnO4/G-FIL 12/13/2011

16 NJ GW ClO2/Cl2 11/29/2011

17 NJ SW MnO4/O3/Cl2 12/14/2011, 4/3/2012

18 NJ SW APT/GAC/Cl2 11/22/2011, 4/3/2012

19 NJ GW Cl2 11/29/2011

20 MN GW GAC/Cl2 10/26/2006 to 06/20/2011

21 NC SW COAG/FLOC/SED/G-FIL/CLM 9/22/2011 9/22/2011

Approach: Utility Sites

Modified from: Dickenson, E.R.V., and C. Higgins. 2016. Treatment Mitigation Strategies for Poly- and Perfluoroalkyl Substances. Denver, Colo.: Water Research Foundation. Reprinted with permission.


PFBA

PFHxA

PFOAPFBS

PFOSPFPeA

PFHxS

PFHpA

• Detected PFASs were in the low ng/L

• Highest levels were in treated

wastewater samples:

• PFPeA = 370 ng/L

• PFOA = 220 ng/L

• Highest level in drinking water was:

• PFHxA = 62 ng/L

• PFBA, PFHxA and PFPeA were frequently detected, but they were not

included in UCMR3

• Longer chain PFCAs were detected less frequently.

• The longer chain PFSA, perfluorodecane sulfonic acid, FTUCAs, FTSAs

(except 6:2 FTSA) were not detected

• N-MeFOSAA, N-EtFOSAA, FOSA, were not detected in ground waters, but

were in 3 surface waters and treated wastewater effluents

Results: Occurrence


Reprinted from Water Research, 51, Appleman, T., Higgins, C.,

Quinones, Q., Vanderford, B., Kolstad, C., Zeigler-Holady, J.

Dickenson, E., Treatment of poly- and perfluoroalkyl substances in

U.S. full-scale water treatment systems, 246-255, (2014), with

permission from Elsevier.


Site: 4 5 7 8 10 11 12 13 14 15 16 17 18 19 20 21

Treatment n= CA AL CO OH CA NJ NJ NJ NJ NJ NJ NJ NJ NJ MN NC

RBF 1 No

AIX 2 No Yes

AER 2 No No

KMnO42 No No

O32 No No

COAG/FLOC/SED 1 No

COAG/FLOC/SED/G-FIL 3 No No No

SOFT 1 No

COAG/DAF/G-FIL 1 No

M-FIL or U-FIL 3 No No No

RO 2 Yes Yes

UV-AOP 1 No

GAC 4 Yes No No Yes

UV 1 No

ClO22 No No

Cl29 No No No No No No No No No

CLM 2 No No

Results: Full-Scale Treatment



Utility # of Carbons #7 #20 #14 #14

Treatment GAC GAC AIX AIX

Sample Date 8/21/2012

4/25/2007 –

4/22/2008 5/30/2012 9/19/2012

PFBA 4 33% -17% -9% 0%

PFPeA 5 74% > 22% 0% 0%

PFHxA 6 91% > 68% 14% -14%

PFHpA 7 > 89% N/A 54% 38%

PFOA 8 > 48% > 92% 76% 73%

PFNA 9 > 37% N/A N/A > 67%

PFBS 4 > 96% N/A 83% 80%

PFHxS 6 > 96% > 41% > 97% > 98%

PFOS 8 > 89% > 95% > 90% > 94%

Results: Full-Scale GAC and AIX Treatments


Results: Full-Scale GAC Treatment

Reprinted from Water Research, 51, Appleman, T., Higgins, C., Quinones, Q., Vanderford, B., Kolstad, C., Zeigler-Holady, J.

Dickenson, E., Treatment of poly- and perfluoroalkyl substances in U.S. full-scale water treatment systems, 246-255, (2014),

with permission from Elsevier.


Methods: Bench-Scale GAC Experiments

—Surface water: DOC = 1.7 mg/L, pH = 6.5

F300 F600 1240C

Manufacturer Calgon Calgon Siemens

Carbon Type Bituminous Coal Bituminous Coal Coconut Shell

Mesh Size, U.S. Sieve 12x40 12x40 12x40

Iodine No., mg I2/g 900 850 1100

Apparent Density, g/cc 0.48 0.62 - 0.65 0.46 - 0.52

Water Source Spiked DI Filtered (1 µm) and spiked Clear Creek Water

PFAA Concentrations (ug/L) 1.0 1.0

# of Columns 3 2 2 2

Carbon F300 F300 F600 1240C

Column Width (cm) 0.7 0.7 0.7 0.7

Carbon Depth (cm) 1 1 1 1

Flow Rate (mL/min) 1 1 1 1

EBCT (min) 0.38 0.38 0.38 0.38

Duration (days) 43 32 52 38



Results: Bench-Scale GAC Experiments

Source: Dickenson, E.R.V., and C. Higgins. 2016. Treatment Mitigation Strategies for Poly- and Perfluoroalkyl Substances. Denver, Colo.: Water Research Foundation. Reprinted with permission.


• Set-up

— Two flat-sheet NF270 membranes in

sequence

— Flow-through operation

— 1 L/min, 18C, pH of 6.7

— Five 30 min increments

• Initial experiment:

— Spiked DI water feed

— Pressures tested from 25-125 psi

Methods: Bench-Scale Nanofiltration Experiments

Component Concentration (mg/L)

MnSO4∙H20 1

Na2SO4 180

NaCl 113

NaHCO3 40

Source: Dickenson, E.R.V., and C. Higgins. 2016. Treatment Mitigation Strategies for Poly- and Perfluoroalkyl Substances. Denver, Colo.: Water Research Foundation. Reprinted with permission.

• Second experiment:

— Spiked artificial ground water used

for feed

— Membranes were fouled to 65%

capacity (DOC = 2.5 mg/L)

— Experiment was repeated with

fouled membranes with constant

flux


Permeate

Flux

(LMH)

PFBA

(214)

PFPeA

(264)

PFHxA

(314)

PFOA

(414)

PFNA

(464)

PFDA

(514)

PFBS

(300)

PFHxS

(400)

PFOS

(500)

AGW-

Virgin

17 > 94 > 97 > 95 > 97 > 98 > 97 > 99 > 99 > 99

33 > 94 > 97 > 95 > 97 > 97 > 97 > 99 > 99 > 99

50 > 94 > 97 > 95 > 97 > 98 > 97 99 > 99 > 99

59 > 95 > 97 > 95 > 97 > 98 > 97 98 > 99 > 99

75 > 94 > 97 > 95 > 97 > 98 > 97 98 > 99 > 99

AGW-

Fouled

17 > 95 > 97 > 95 > 97 > 98 > 97 > 99 > 99 > 99

33 > 94 > 97 > 95 > 97 > 97 > 97 > 99 > 99 > 99

50 > 94 > 97 > 95 > 97 > 97 > 96 > 99 > 99 > 99

59 > 94 > 97 > 95 > 97 > 98 > 97 > 99 > 99 > 99

75 > 94 > 97 > 95 > 97 > 98 > 97 > 99 > 99 > 99

DI-Virgin

20 > 93 > 97 > 95 > 97 > 98 > 97 97 > 97 > 99

28 > 93 > 97 > 95 > 97 > 98 > 98 98 98 > 99

44 > 93 > 97 > 95 > 95 > 97 > 97 96 97 > 99

59 > 94 > 97 > 95 > 97 > 98 > 98 96 96 > 99

70 > 93 > 97 > 95 > 97 > 97 > 98 95 96 > 99

Results: Bench-Scale Nanofiltration Experiments



Results: Treatment Technologies Summary

PFBA 214 assumed assumed

PFPnA 264

PFHxA 314

PFHpA 364

PFOA 414

PFNA 464 unknown assumed assumed

PFDA 514 unknown assumed assumed

PFBS 300

PFHxS 400

PFOS 500

FOSA 499 unknown unknown unknown assumed unknown assumed unknown

N -MeFOSAA 571 assumed unknown assumed assumed assumed unknown

N -EtFOSAA 585 unknown assumed assumed assumed assumed unknown

KMnO4,

O3, ClO2,

Free Cl2,

NH2Cl,

UV,

UV/AOP

COAG/

SED/

G- or

M-FIL

M.W.

(g/mol)NF ROAER

COAG/

DAFAIX GAC



o PFAAs are extremely persistent and bioaccumulative.

o Some are highly water soluble thus a major pathway for human exposure is

the consumption of contaminated drinking water.

o Ineffective water treatment techniques:

- Ferric or alum coagulation

- Granular filtration, microfiltration, ultrafiltration

- Aeration/oxidation: permanganate, ultraviolet/hydrogen peroxide

- Disinfection: ozone, chlorine dioxide, chlorine, and chloramines

o Anion exchange and granular activated carbon treatment preferably removed

longer-chain PFAAs and the PFSAs compared to the PFCAs.

o Reverse osmosis and nanofiltration demonstrated significant removal for all

the PFAAs, including PFBA (perfluorobutanoic acid).

Conclusions


• Oscar Quiñones, Brett Vanderford, Janie Zeigler-Holady, Dr. Riley

Flowers, and Josephine Chu - Southern Nevada Water Authority

• Tim Appleman, Dr. Chris Bellona, Dr. Jörg Drewes, Dr. Dean Heil,

and Dr. Jennifer Guelfo - Colorado School of Mines

• Dr. Scott Summers - University of Colorado, Boulder

• Dr. David Kempisty - Air Force Institute of Technology

• Dr. Detlef Knappe - North Carolina State University

• Dr. Judy Louis and Dr. Gloria Post, New Jersey Department of

Environmental Protection

• Chad Kolstad and Dr. Carin Huset, Minnesota Department of Health

Acknowledgements

wrf webcast treatment mitigation strategies for poly-and ...€¦ · —pfos: 1,000,000 ng/l...

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