Emergence of PFAS (Per- and Polyfluoroalkyl Substances)

Federation of New York Solid Waste Associations Annual Conference

May 23, 2017

Presentation Outline

• Introduction • PFAS Basics • Health Effects and Risk Assessment • Site-Specific Investigations • Fate-and-Transport / Air Deposition • Conclusions and Discussion

What is a safe level of PFAS in drinking water?

1) 0 parts per trillion (ppt) 2) 14 ppt (NJ proposed standard) 3) 20 ppt (VT standard) 4) 70 ppt (EPA Lifetime Health Advisory) 5) Some level > 70 ppt

How many Americans have > 70 ppt of PFAS in drinking water?

1) < 100 2) 100 to 10,000 3) 10,000 to 1,000,000 4) > 1,000,000

What is a typical level of PFAS in blood?

1) < 1 part per billion (ppb) (not detectable) 2) 2 ppb 3) 10 ppb 4) 20 ppb

Which type of site has PFAS not been found at?

1) Chromium plating facilities 2) Dry cleaning facilities 3) Firefighting training facilities 4) Landfills

Wisdom from the Past?

“We should remember that risk assessment data can be like the captured spy: If you torture it long enough, it will tell you anything you want to know.”

William Ruckelshaus (1984), Risk in a Free

Society, Risk Analysis, 4(3):157-162

What Level of PFAS in Drinking Water is Safe?

1

10

100

1000

PFAS

Con

cent

ratio

n in

Drin

king

Wat

er (n

g/l,

or p

pt)

At Risk

Safe

PFOS + PFOA = 70 ppt

• U.S. EPA – January 2009

• PFOA = 400 ppt • PFOS = 200 ppt

– Early 2016 • PFOA = 100 ppt

– May 2016 • PFOA + PFOS = 70 ppt

• New Jersey – 2009

• PFOA = 40 ppt – 2016

• PFOA = 14 ppt • Vermont

– March 2016 • PFOA = 20 ppt

Thinking About 70 ppt

• 70 ppt is a small number (difficult to fathom)

• Opinion: 70 ppt is a convenient and useful number

• 70 ppt is also a costly number • The $26,000,000 question: Is

70 ppt a necessary number? • Is 70 ppt “the” number?

Wisdom in (Greater) Context

“When the action so forced has dire economic or social consequences, the person who must make the decision may be sorely tempted to ask for a “reinterpretation” of the data. We should remember that risk assessment data can be like the captured spy: If you torture it long enough, it will tell you anything you want to know. So it is good public policy to so structure an agency that such temptation is avoided.”

Ruckelshaus (1984), Risk in a Free Society, Risk Analysis, 4(3):157-162

Zero Risk?

• Opinion: Zero risk is impractical even if somehow attainable

• Recent reactions suggest this opinion is not held by all – PFAS in drinking water – Lead in drinking water

• Congress: Safe drinking water is essential to the protection of public health

A Rose is a Rose …

• What do the following terms mean? – Safe – Significant Risk – or – Insignificant Risk – Clean – Conservative – Protective

• Different things to different people – that's what happiness is (?)

Remember the Alar Scare? Or how about microwave popcorn?

• Alar – Daminozide – was used beginning in 1963 to regulate apple growth/ripening

• In 1989 EPA proposed a ban based on potential cancer risks

• Banned from food crops, still OK for ornamentals • Toxicity hotly debated and publicized • Uncertainties never fully resolved • PFAS analogy? January 1, 2006 ES&T: “It’s in the microwave popcorn, not the Teflon pan”

Examples of Chemical Challenges

• Polychlorinated dibenzo(p)dioxins and furans • Mercury • Arsenic and lead in drinking water • Formaldehyde and acrolein in air • Radon • Commonality: Background exposure levels

are of similar magnitude to “risky” levels

More from Administrator Ruckelshaus

But when the risks estimated through such assessments are substantial, so that some action may be in the offing, the stacking of conservative assumptions one on top of another, becomes a problem for the policymaker. If I am going to propose controls that may have serious economic and social effects, I need to have some idea how much confidence should be placed in the estimates of risk that prompted those controls. I need to know how likely real damage is to occur in the uncontrolled, partially controlled, and fully controlled cases. Only then can I apply the balancing judgments that are the essence of my job. This, of course, tends to insert the policymaker back into the guts of risk assessment, which we’ve agreed is less than wise.

Ruckelshaus (1984), Risk in a Free Society, Risk Analysis, 4(3):157-162

PFAS BASICS

PFAS – A class of chemicals

• PFAS – Per- and Polyfluorinated Alkylated Substances

• PFCs– Perfluorinated Compounds

O

OH

F F F F F F F F

F F F F F F F

perfluorooctanoic acid (PFOA)

perfluorooctane sulfonic acid (PFOS)

S

O

O

OH

F F F F F F F F

F F F F F F F

F

F

PFAS Production and Use in U.S.

• PFAS first manufactured in 1949 • PFOS

– Phased out in 1990s – Domestic large-scale use discontinued in 2002

• PFOA – Phased out starting in 2006 – Domestic manufacture ceased – Still in use (imports/existing stock)

• PFAS usage shifted to shorter-chain compounds

PFAS in Public Drinking Water Hu et al., ES&T Letters, August 2016,

http://pubs.acs.org/doi/abs/10.1021/acs.estlett.6b00260

PFAS – A class of chemicals

O

OH

F F F F F F F F

F F F F F F F

Fluorocarbon tail • Strong bonds • Hydrophobic • Oleophobic • Varying length

Functional group • Strong to weak acids • Hydrophilic

perfluorooctanoic acid (PFOA)

Uses of PFAS

• Fabric treatments • Chemical/oil/heat-resistant coatings • Performance materials

– Plastics, adhesives, waxes

• Process surfactants • Fire fighting (aqueous film forming

foams [AFFF])

• Release of aqueous film forming foams (AFFF) via firefighting

• Household products • Runoff of stormwater and street dust • Industrial facilities • PFAS wastes • Others

Sources to the Environment

Three Potential Pathways for Industrial Releases

Soil

Groundwater

*solids from wastewater

PFOA/PFOS Fate and Transport Properties

• Very soluble • Some sorption • Not volatile • Very stable • Surfactant quality

O

OH

F F F F F F F F

F F F F F F F

perfluorooctanoic acid (PFOA)

PFAS Sampling and Analysis

• Sampling – PFAS prevalent in field supplies

& PPE

• Analysis – Variability across labs – Large list of potential analytes – Reporting limits vary (~1-10

ppt)

PFAS Treatment and Remediation (soil and groundwater)

• Offsite disposal/incineration • Groundwater extraction

– Granular activated carbon (GAC) – Ion Exchange

• In-situ –Oxidation/Reduction –Stabilization

PFAS in Landfill Leachate Lang et al., ES&T, January 2017,

http://pubs.acs.org/doi/abs/10.1021/acs.est.6b050055

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

B E F G H I J K L M N O P Q R S T U

Conc

entr

atio

n (p

pt)

Landfill ID

PFOA+PFOS

Airborne PFAS from Landfills Ahrens et al., ES&T, April 2011,

http://pubs.acs.org/doi/abs/10.1021/es1036173

Is this a lot of PFAS? 1,000 g/yr

× 109 ng/g ÷ 70 ng/L 1.43 × 1010 L/yr

Or 3.78 billion gallons per

year @70 ppt PFAS

However: •Most of the mass is NOT PFOA/PFOS •Probably a global transport issue

HEALTH EFFECTS AND RISK ASSESSMENT

Recent Review of PFAS Toxicity

• Drs. David Klein & Joseph Braun, Brown University, 10/3/2016, NEWMOA webinar

– http://www.newmoa.org/events/docs/236_210/KleinPFAS_ToxWebinarOct2016.pdf – http://www.newmoa.org/events/docs/236_210/BraunPFAS_ToxWebinarOct2016.pdf

• Summary: both laboratory (animal) and epidemiology studies pointing to various developmental (non-cancer) effects

• Evidence on cancer is suggestive but inconsistent, but also of secondary importance

PFAS Health Effects and Toxicology

• Most studies have focused on PFOA and PFOS

• Both PFOA and PFOS bioaccumulate in human blood, PFOS more so

• PFAS chain length roughly relates to half-life and potential toxicity

• PFAS persist in humans for years, but in rats and mice for only days to weeks

C8 Science Panel Studies http://www.c8sciencepanel.org/prob_link.html and Shin et al (2011). Environ Health Perspect. 119(12):1760–1765.

• Focused on PFOA from Dupont’s Washington Works facility in Wood County, WV

• Conducted as a condition of a lawsuit settlement

• Populations studied – Community residents of six

Mid-Ohio River Valley districts with PFOA-contaminated drinking water supplies

– Former workers at the Dupont plant

– Combined residents and workers (for follow-up cancer studies)

C8 Science Panel Studies http://www.c8sciencepanel.org/prob_link.html

• Probable links between PFOA exposure and: – Diagnosed high cholesterol – Ulcerative colitis (autoimmune disease) – Thyroid disease – Testicular and kidney cancers – Pregnancy-induced hypertension

C8 Science Panel Studies http://www.c8sciencepanel.org/prob_link.html

• No probable links between PFOA exposure and: – Diagnosed hypertension – Coronary artery disease – Chronic kidney disease – Liver disease – Osteoarthritis – Rheumatoid arthritis, lupus, Type I diabetes, Crohn’s disease, and multiple

sclerosis (autoimmune diseases other than ulcerative colitis) – Parkinson’s disease – Common infections (including influenza) – Neurodevelopmental disorders in children (e.g., ADD) – Asthma and chronic obstructive pulmonary disease (COPD) – Stroke – Nineteen types of cancer (other than kidney and testicular) – Type II diabetes – Birth defects – Miscarriages and stillbirths – Preterm birth and low birth weight

Recent Review of PFAS Toxicity Klein & Brown NEWMOA Webinar, 10/3/2016

Key Animal Toxicity Studies Effect Investigators Animal Notes

Skeletal variations in offspring

Lau et al. (2006) Mice LOAEL; Basis of EPA’s 70 ppt health advisory

Testicular cancer Butenhoff et al. (2012)

Rats Leydig cell tumors – human relevance unclear

Increased liver weight in offspring

Quist et al. (2015) Mice Signs of chronic stress into adulthood

Mammary gland development in offspring

Tucker et al. (2015) Mice Human relevance unclear

U.S. EPA’s Lifetime Health Advisory

• Issued May 19, 2016 • Applies to sum of PFOA + PFOS • 70 ng/l based on developmental study in mice

– Basis: Lowest effects level of 1 mg/kg-d delayed ossification in pups and hastened male puberty

– Metabolic adjustment to 0.0053 mg/kg-d to account for much longer half-life in humans

– Add safety/uncertainty factors totaling 300: • 10 (sensitive individuals) • 3 (inter-species) • 10 (LOAEL to NOAEL)

to get reference dose of 0.00002 mg/kg-d = 20 ng/kg-d – Only 20% of exposure from drinking water

PFAS Reference Dose

• Opinion: EPA’s Reference Dose of 20 ng/kg-d for PFOA+PFOS has received inadequate peer review

• What studies/effects are proper for the basis? – Liver enlargement proposed then dropped – Chosen development effects are arguably tenuous

• Other authorities have assigned higher values Authority

Reference Dose (ng/kg-d)

PFOA PFOS

U.S. EPA (2016) 20 (total for both)

European Food Safety Authority (2008) 150 1500

Danish EPA (2015) 30 100

Health Canada (2016, proposed) 25 60

Drinking Water Criteria Examples

Maximum Contaminant Level (MCL)

• Legally enforceable • 2 liter/day water ingestion • 70 kg adult • Background exposure 80%

Lifetime Health Advisory (LHA) • Guidance • 4.3 l/day water ingestion • 70 kg adult • Background exposure 80%

ng/l 140l/d 2

kg 70d-ng/kg 202.0=

×× ng/l 65l/d 3.4

kg 70d-ng/kg 202.0=

××

Background Exposure to PFAS

• Is it reasonable/appropriate/necessary to assume that 80% of PFAS exposure derives from non-drinking water sources?

• Can we derive a better background exposure estimate?

• What estimates are available in the literature?

Background Exposure to PFAS

• NJ’s 40 ppt groundwater standard based on doubling of PFAS exposure via drinking water

• Background estimate: – ½ × 40 ng/l × 2 l/d = 40 ng/day

• Reference Dose (RfD) exposure: – 20 ng/kg-day × 70 kg = 1,400 ng/day

• Background = 40/1,400 = 3% of RfD

Background Exposure to PFAS

• Gebbink et al. (2015) PFOA+PFOS exposure estimates for a 70 kg adult

• Observation: Reserving 80% of RfD for background seems conservative

• But … all PFAS are not considered, and what percentile background is appropriate?

Low Intermediate High Exposure (ng/day) 9 48 343

% of RfD 0.7% 3% 25%

PFOA in Blood in U.S. Population NHANES data http://www.cdc.gov/biomonitoring/pdf/FourthReport_UpdatedTables_Feb2015.pdf

0

1

2

3

4

5

6

1998 2000 2002 2004 2006 2008 2010

Conc

entr

atio

n (µ

g/L)

Geo Mean PFOA Levels in Blood (National Data)Error bars = 95% confidence interval

Current level ~2 μg/L (ppb)

Average PFOA Levels in Blood (µg/L) (https://www.health.ny.gov/environmental/investigations/hoosick/docs/qandabloodtestingshort.pdf)

PFAS in Drinking Water & Blood Serum

• Elevated PFAS levels in water ⇒ increased PFAS in blood • Typical ratios (Braun, 2016 NEWMOA webinar)

– PFOA: 125 µg/l (blood serum) / µg/l (drinking water) – PFOS: 175 µg/l (blood serum) / µg/l (drinking water)

Monitored PFOA Ratios in Blood Serum to Drinking Water (Braun, 2016 NEWMOA webinar)

Ratio of 150 means 10 ppt in water => 1.5 μg/l in blood

SITE SPECIFIC INVESTIGATIONS

Downloaded 3/1/2017 https://www.des.nh.gov/organization/commissioner/pfoa.htm

Plastics Facility

Merrimack Litchfield

Merrimack River

~1 mile

Bennington, VT Amherst, NH

Hoosick Falls, NY Pennsgrove, NJ Hoosick Falls, NY Ohio/West Virginia

Downloaded 5/5/2017 https://www.des.nh.gov/organization/commissioner/pfoa.htm

AFFF Training

Fire Station

Downloaded 5/5/2017 https://www.des.nh.gov/organization/commissioner/pfoa.htm

Overburden contours and annotations adapted from various reports available on NHDES OneStop, prepared for the Coakley Landfill Group by CES, Inc.

Surface Water

Approx. POA + PFOS = 70 ppt

Approx. POA + PFOS = 500 ppt

Image courtesy of NJ DEP

Compost Facility NYS DOH/DEC 3/13/2017 Press Release

• Yard waste & paper mill sludge compost • Investigations ongoing at this facility and

other facilities that use paper mill sludge and/or recycled paper process sludge – Agricultural fields – Surface water – Groundwater

Biosolids Reuse/Disposal 2003 USEPA Study

Farmland 60%

Landfills 17%

Incinerated 20%

Mine Reclamation

3%

Biosolids Case: LA v. Kern County November 2016, Superior Court of CA, Case # 242057

• Kern County (CA) sued by Los Angeles • 11 – 30 ppt PFAS in groundwater • Tentative findings:

– No proof biosolids contaminated groundwater – No evidence of health effects – State interests > Local interests

PFAS in Chrome Plating Effluent USEPA Region 5, 2009 Study

1 2 3 4 5 6 7 8 9 10 11

Facility #

Conc

entr

atio

n (p

pt)

10,000

20,000

30,000

40,000

50,000

60,000

Three Potential Pathways for Industrial Releases

Soil

Groundwater

*solids from wastewater

FATE AND TRANSPORT AIR DEPOSITION

Importance of PFAS Fate & Transport

• Understanding and confirmation of conceptual site models

• Retrospective estimates of exposure to PFAS in drinking water

• Prospective estimates of changes in PFAS concentrations in groundwater

PFAS Airborne Transport & Deposition

• Disclaimers – Models not based on any specific investigation – No intent to be precise – order of magnitude

models designed to identify basic factors

• Motivations/uses – Gauge consistency of PFAS data within a

conceptual site model (CSM) – Identify areas of refinement or exploration

How Much PFAS in Air is Needed to Contaminate Groundwater?

• Assume: – PFAS deposits and mixes with precipitation – Deposition velocity 1 cm/s – 1 m annual precipitation depth

• Find by mass balance: – 3.2 ng/m3 in air produces 1,000 ng/l in water

• Perspective: – 70 – 170 ng/m3 detected in air near Dupont in WV – > 24 – 50 ng/m3 modeled near NH facility in 2004

What PFAS Emission Rate Produces Observed Air Levels?

• Ballpark Assumptions: – PFAS in air at 10 ng/m3

– Emission height ~ 30 m – Class D/E stability – Wind speed ~5 m/s – Transport distance ~1,000 to 1,500 m

• Guesstimate: – Impact Cu/Q of 5.0×10-5 m-2 (Turner’s Workbook) – Implied emission Q = 0.008 lb/hr = 70 lb/yr

PFAS Emissions

• Chromium plating facility (1) – 1 lb/yr PFOS based on 4.9 μg/m3 in vented exhaust

• Coating manufacturer in NH – reported (2) – 980 lb/yr in 2005 – 0.1 lb/yr IN 2016

• Dupont plant in Washington, WV (3) – > 10,000 lb/yr from 1978 through 2002 – 34,000 lb/yr peak in 1999

(1) NAVFAC TR-2243-ENV, March 2004 (2) Courtesy of NH Department of Environmental Services (3) Paustenbach et al (2007), J Toxicol Environ Health 1:28-57

Deposition is Cumulative Over Time

• Pollutant disperses into the environment – Since the compound is stable, it doesn’t break down and works into the soil

and water layers • Each year adds a new layer

Seeps into soil and water table

1998 1999 2000

Deposits from air

2001 2002

2003

Courtesy of NH Department of Environmental Services

Air Deposition Modeling Contours Roughly Match Well Contamination Pattern

Preliminary AERMOD predictions for a single modeling year

Courtesy of NH Department of Environmental Services

Soil: The Critical PFAS Reservoir?

Atmospheric deposition

Accumulation/Depletion

Infiltration

Leaching

Soil

Groundwater

Study of PFOA and PFOS in Soil

Xiao et al. (2013), U-Minnesota, http://conservancy.umn.edu/handle/11299/148999

Roadside locations, Minneapolis/St. Paul region

ppb levels detected

Tong soil from manufacturing waste dump

Is Soil a Reservoir for PFAS?

• Estimate 0.014 g/m2 PFOA/PFOS in soil based on: – 1 ng/g (ppb) of PFOA/PFOS in soil – Contaminated depth of 30 ft – Soil bulk density of 1,500 kg/m3

• Annual deposition rate of 0.003 g/m2-yr based on previous example: – based of 10 ng/m3 PFOA/PFOS in air – deposition velocity of 1 cm/s

Summary & Considerations All Models are Wrong, Some are Useful

• Order-of-magnitude models are possibly instructive/suggestive, but not conclusive

• Need to consider other factors – Better and more complex models – Proper input and diagnostic data for models – Site-specific hydrology – PFAS retardation factors – Leaching parameters

CONCLUSIONS AND DISCUSSION

Conclusions

• PFAS have emerged and EPA’s 70 ppt Lifetime Health Advisory is a challenging benchmark • Millions of people are possibly at risk • Costs to investigate/mitigate are high • Risk assessment methods need to evolve

• The PFAS story is not over • Policy makers (and everyone) can benefit from delving

into the science • Risk communication / uncertainties / conservatism • Informed risk-based decision-making?

Discussion

With thanks to the NH Department of Environmental Services

Sanborn, Head and Associates, Inc.

Stephen G. Zemba, Ph.D, P.E. Project Director szemba@sanbornhead.com T 802.431.0539

Harrison Roakes Senior Project Engineer hroakes@sanbornhead.com T 603.415.6156

Thank you for your attention!

SPARE SLIDES

Recent Review of PFAS Toxicity Klein & Brown NEWMOA Webinar, 10/3/2016

• Epidemiological studies indicate associations between PFAS exposure and: – Reduced birth weight – Increased risk of obesity/overweight and excess

adiposity (possibly through alterations in child growth)

– Decreased duration of lactation

Does PFAS Exposure Cause Cancer? Draft (2015) ATSDR Toxicity Profile

There is limited information on whether perfluoroalkyls can cause cancer in humans. Some increases in prostate, kidney, and testicular cancers have been found in workers or in community members living near a PFOA facility. These results should be interpreted cautiously because the effects were not consistently found and most studies did not control for other potential factors such as smoking. Feeding PFOA and PFOS to rats caused them to develop tumors. Some scientists believe that, based on the way this happens in rats and the differences between rats and humans, humans would not be expected to get cancer. Others believe that it is possible for perfluoroalkyls to cause cancer in humans, and the studies in rats should not be dismissed. More research is needed to clarify this issue.

Does PFAS Exposure Cause Cancer? U.S. EPA (2016) Drinking Water Health Advisory

Under EPA’s Guidelines for Carcinogen Risk Assessment, there is Suggestive Evidence of Carcinogenic Potential for PFOA. Epidemiology studies demonstrate an association of serum PFOA with kidney and testicular tumors among highly exposed members of the general population. Two chronic bioassays of PFOA support a positive finding for the ability of PFOA to be tumorigenic in one or more organs of rats, including the liver, testes, and pancreas.

Sources of Toxicity Data

• Laboratory Studies – Limited numbers of animals – Doses are orders of magnitude greater than

environmental exposure – Must assume relevance to humans and shape of dose-

response relationship

• Epidemiological Studies – Compare exposed and control populations – Statistical power requires large populations – Confounding factors difficult to account for – Are positive associations proof of causality?

Recent Review of PFAS Toxicity Klein & Brown NEWMOA Webinar, 10/3/2016

• Basic Conclusion: Both laboratory (animal) and epidemiological (human) studies are pointing to developmental effects from PFAS exposure

• More work remains: – Unstudied PFAS – Further integration/coherency

Does PFAS Exposure Cause Cancer? Summary Interpretation

Some evidence of cancer in both epidemiological and animal studies

BUT

Uncertainties in the toxicity studies preclude a definitive finding

SO, MAYBE YES, BUT

At present, the determination is not critical

BECAUSE

EPA’s 70 ng/l Lifetime Health Advisory corresponds to a cancer risk below the level of regulatory concern for non-cancer effects

PFOA in Blood – C8 Health Project Shin et al (2011). Environ Health Perspect. 119(12):1760–1765.

Blood Testing at Hoosick Falls https://www.health.ny.gov/environmental/investigations/hoosick/docs/infosheetgrouplong.pdf

Comparison with National Data (Geometric means, µg/L) http://www.cdc.gov/biomonitoring/pdf/FourthReport_UpdatedTables_Feb2015.pdf

Gender Hoosick Falls 2009-2010

Nationwide Female 22.3 2.69 Male 29.7 3.53

Blood Testing at Hoosick Falls Geometric means, µg/L, by sex and age

https://www.health.ny.gov/environmental/investigations/hoosick/docs/infosheetgrouplong.pdf

Typical level ~2 μg/L (ppb)

Downloaded 5/5/2017 https://www.des.nh.gov/organization/commissioner/pfoa.htm

Overburden contours and annotations adapted from various reports available on NHDES OneStop, prepared for the Coakley Landfill Group by CES, Inc.

1,280/1,250

Approx. POA + PFOS = 70 ppt

Approx. POA + PFOS = 500 ppt

250/450

420/311

380/308

<200/90

Surface water (ppt): 1,4-Dx/PFOA+PFOS

Approx. 1,4-Dx = 10,000 ppt

Approx. 1,4-Dx = 3,000 ppt

Adapted from: Results of Perfluorinated Chemical Groundwater Sampling for Selected Wells within OU-1 and OU-2 at the Coakley Landfill - North Hampton, New Hampshire prepared for the Coakley Landfill Group by CES, Inc., dated September 2, 2016.

Adapted from: Results of Perfluorinated Chemical Groundwater Sampling for Selected Wells within OU-1 and OU-2 at the Coakley Landfill - North Hampton, New Hampshire prepared for the Coakley Landfill Group by CES, Inc., dated September 2, 2016.

1,4-Dx = 3,000 ppt

1,4-Dx = 50,000 ppt

1,4-Dx = 100,000 ppt

PFAS Landfill Leachate Lang et al., ES&T, January 2017,

http://pubs.acs.org/doi/abs/10.1021/acs.est.6b050055

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

B E F G H I J K L M N O P Q R S T U

Conc

entr

atio

n (p

pt)

Landfill ID

Total PFAS PFOA+PFOS

PFAS from Landfills Ahrens et al., ES&T, April 2011,

http://pubs.acs.org/doi/abs/10.1021/es1036173

PFAS from Landfills Ahrens et al., ES&T, April 2011,

http://pubs.acs.org/doi/abs/10.1021/es1036173

Sampling Materials

Generally Allowable • HDPE • LDPE • PVC • Silicon • Buna-nitrile • Stainless steel

Generally Prohibited • Teflon®

• Viton® • PTFE • PFA • ETFE • … • Other fluoropolymers • MANY CONSUMER

PRODUCTS