pfas: like nothing we’ve seen before

PFAS: Like Nothing We’ve Seen Before

MI Chapter APWA Annual ConferenceMay 23, 2019

Scott Bell, P.E.

Contents• What are PFAS?

• PFAS uses and sources

• What makes PFAS so different?

• Exposure risks and regulatory standards

• Michigan PFAS response

• Regulatory Updates

• Technical Updates

• Other sources of information

What are PFAS?

PFAS = Per- and PolyfluorinatedAlkyl Substances• Manmade organic compounds with 4+ carbon atoms in a chain, plus a

“functional group”

• Fluorine attached to carbons instead of hydrogen

– Perfluorinated = all carbon atoms have attached fluorine atoms

– Polyfluorinated = most carbon atoms have attached fluorine atoms

What are PFAS? PFAS are surfactants

• Reduce surface tension in liquids – Key reason for use in plating

• Both hydrophobic and hydrophilic

• Soluble in water

• Low volatility

• Extremely stable– Carbon-fluorine bond

What are PFAS?

When people say “PFAS”, they usually mean:

• One or more regulated PFAS, such as PFOS (perfluorooctanesulfonic acid) or PFOA

(perfluorooctanoic acid), which are the most regulated PFAS in the U.S.

OR

• The sum of the 14 PFAS measured in drinking water using USEPA Method 537.1

Per- and Polyfluorinated

Substances (PFAS)

Per-fluorinated

Poly-fluorin

ated

Per-fluoro-alkylAcids

(PFAAs)

Non-PFAAs

Perfluoroalkyl

Carboxylic Acids (PFCAs)

Perfluoroalkyl

Sulfonic Acids

(PFSAs)

C4 - PFBAC5 - PFPeAC6 - PFHxAC7 - PFhpAC8 - PFOAC9 - PFNAC10 - PFDAC11 - PFUnAC12 - PFDoAC13 - PFTriDAC14 - PFTeDA

C4 - PFBSC5 - PFPeSC6 - PFHxSC7 - PFhpSC8 - PFOSC9 - PFNSC10 - PFDS

What are PFAS?

Current commercial labs will report these 11 PFCAs and 7 PFSAs, along with 6 other “precursor compounds”

PFAS Uses and Sources

1938• DuPont discovered polytetrafluoroethylene (PTFE)

1945• 3M licensed electrochemical fluorination ECF, DuPont registers Teflon trademark

1952• Scotchgard formula discovered by 3M

1954• PTFE first used for non-stick cookware

Mid-1960s

• Use of perfluorocarboxylates (PFCAs) in consumer products (textile and leather treatment, cookware, floor polish, etc.) becomes widespread

Late 1960s

• Use of PFAS in firefighting foam (aqueous film-forming foam, AFFF) begins

2002• 3M voluntarily discontinues production in US


Food packaging paper

Pharmaceuticals Fabric protection

Outdoor apparel

Non-woven fabrics

Leather treatment

Electronics Non-stick cookware

PFAS in Consumer & Commercial Goods

Aqueous film-forming foam (AFFF)

Chrome plating

Landfill leachate

Major Industrial & Commercial PFAS Uses(Current Regulatory Focus)


Other industries: petroleum refining, molding, forging, etc.

Biosolids land application

Paper productionLandfill leachate

Potential Sources of PFAS Under Investigation


What Makes PFAS So Different?

• PFAS are toxic to people

• PFAS stick around a long time.

• PFAS are everywhere.

• There are a lot of PFAS compounds and

we can’t measure all of them.


Human health risks – multiple PFAS health concerns (ATSDR*):

• Affect growth, learning, and behavior of infants and older children

• Liver damage

• Thyroid disease

• Decreased fertility

• Asthma

• Increase serum lipid (cholesterol) levels

• Increased risk of cancer (esp. kidney, testicular, thyroid)

• Decreased birth weight and other birth defects

• Possible links to osteoarthritis and risk of early menopause

Source: https://www.atsdr.cdc.gov/pfas/health-effects.html


PFAS stick around a long time

Chemical Group Half Life in Soil

PFAS 1–3 years1

PCBs ~2.6 years2

Dioxins ~13 years2

2NIH, July 20142California OEHHA, 2000


PFAS stick around a long time

Chemical Group Half Life in Human Tissue

PFAS 2 – 9 years1

Dioxins 7 – 11 years2

PCBs 10 – 15 years3

1USEPA, 20092World Health Org., Oct. 20163Ritter, et al., Env. Health Perspectives, v119 n2 Feb. 2011


PFAS stick around a long time• Referred to by many as the “forever chemicals”.

• The carbon-fluorine bond is one of the strongest chemical bonds known.

• Transformations in the environment most often involve replacement of

non-fluorine atoms with fluorine atoms – from “poly” to “per”.

• PFAS are not destroyed by standard incinerators – some studies suggest

>900o C is necessary for destruction.


PFAS are everywhere• A 2009 peer-reviewed paper in ES&T

concluded that 135,000 tons of POSF,

a compound created to synthesize

other PFAS, were produced globally

between 1970 – 2002.

• Estimate based on 3M production

records.

• Production has continued elsewhere in

the world since 2002.


PFAS are everywhere• A 2015 report by a European

environmental agency concluded that

there are “more than 3,000

commercial highly fluorinated

substances in circulation on the

global market.”


PFAS are everywhere• A USEPA national drinking water study

(2013-2015) found PFAS in 194 of

4,864 public water supplies tested.

• These supplies serve 16.5 million

people in 33 states

Map credit: Hu, et al., ES&T, 2016


PFAS are everywhere• 2018 MDEQ sampling found PFAS in

179 of 1,744 water supplies tested.

• All but 2 were below the Federal screening level of 70 ppt for PFOA & PFOS.

• Quarterly monitoring started on 62 (map).

• Sampling of 750 non-community wells planned this year.

Map credit: Hu, et al., ES&T, 2016


There are a lot of PFAS (and we can’t measure them all)

• In 2018, the OECD published their

findings that 4,730 different PFAS

compounds had been catalogued.

• Compare this with the “standard list” of

24 PFAS compounds currently reported

by commercial labs.

PFAS 4,730 compounds

PCBs 209 congeners

Dioxin 75 compounds


There are a lot of PFAS (and some of the ones we can’t measure can transform to the regulated compounds)


Potential liability concern for local governments

• Drinking water supplies

• Wastewater treatment plants– Discharge limits

– Land application of biosolids

• Airports (AFFF)

• Landfills (both closed and operating)

• Fire departments (AFFF)– Past fire response locations?

Exposure Risks and Standards

Human exposure pathways

• General public

– Primary exposure through ingestion (water & food)

– Dermal contact and inhalation are not considered significant for general public

– Per the ATSDR:

“Studies have shown that only a small amount of PFAS can get into your body through your skin. Therefore, showering and bathing in water containing PFAS should not increase exposure. Washing dishes in water containing PFAS should not increase exposure.”

• Workers in industries where high-concentration PFAS materials are used may be exposed through inhalation or dermal contact


Ecological risks

• PFAS are persistent and bioaccumulative.

• Ecological receptors are not currently drivers in Michigan, except as human food

source.

• Standards related to aquatic toxicity are much higher than for human health.


MDEQ: State surface water quality standards (Rule 57 values, mg/l)

• HNV (DW) – Maximum water concentration at which adverse noncancer effects are not likely to occur in the human population from lifetime exposure through drinking the water.

• HNV (NDW) – Maximum water concentration at which adverse noncancer effects are not likely to occur in the human population from lifetime exposure through conducting water-related recreation activities or consuming fish from the water.

• FCV – The concentration that does not allow injurious or debilitating effects in an aquatic organism resulting from repeated long-term exposure.

• AMV – Maximum concentration to which an aquatic community can be exposed briefly without resulting in unacceptable effects.

• FAV - level of a chemical or mixture of chemicals that does not allow the mortality or other specified response of aquatic organisms to exceed 50% when exposed for 96 hours.

Compound Human NoncancerValue (DW)

Human NoncancerValue (NDW)

Final Chronic Value

Aquatic MaximumValue

Final Acute Value

Year

PFOS 0.011 0.012 140 780 1,600 2014

PFOA 0.42 12 880 7,700 15,000 2010/11


MDEQ: State groundwater cleanup values (Part 201 criteria)

*GSI – Groundwater/surface water interface.

Compound Groundwater -Drinking Water Pathway (mg/l)

Soil –Drinking Water Pathway (mg/kg)

Groundwater – GSI* Pathway (mg/l)

Soil – GSI* Pathway (mg/kg)

Year

PFOS 0.07 - 0.012 0.24 2018

PFOA 0.07 - 12 10,000 2018

PFOS + PFOA 0.07 - - 2018

Michigan PFAS Response

Wolverine Worldwide

• May 2016: USEPA - HALs for PFOS & PFOA = 70 ppt.

• January 2017: MDEQ learns of PFAS at former landfills used by

Wolverine Worldwide, groundwater testing begins, PFOS found.

• October 2017: Wolverine announces whole-house water filters for

300 homes.

• November 2017: Michigan PFAS Action Response Team (MPART)

created by Governor Snyder.

– temporary body “to investigate sources and locations of PFAS

and protect drinking water and public health.”

• January 2018: MDEQ announces groundwater cleanup criteria

under Part 201; Accelerated testing begins on rivers, public water

supplies, other sites.

Michigan PFAS Response: fast, aggressive

Since 2017, Michigan has been looking for PFAS “sites”

• Military bases

• Industrial dischargers

• Airports

• Municipal WWTPs

• Landfills

• Public water supplies

• Water bodies (lakes & rivers)

• Old fire sites

Michigan PFAS Response: multi-agency

• EGLE (formerly MDEQ) is the lead agency –multiple divisions involved

– Water Resources Division (WRD)

– Remediation and Redevelopment Division (RRD)

– Drinking Water and Municipal Assistance Division

• Michigan Dept. of Health & Human Services

– Consultation when drinking water supplies are potentially at risk

– Responsible for issuing fish consumption advisories

• Michigan Dept. of Natural Resources

– Routinely conducting fish tissue testing for PFAS, since 2011

– Currently (2018) conducting deer tissue testing for PFAS

• County Health Departments

– Consultation when drinking water wells are potentially at risk

• USEPA –No known involvement in MI PFAS sites except Wolverine

Michigan PFAS Response: low standards

State surface water quality standards

Compound Human Noncancer Value (DW)

Human NoncancerValue (NDW)

Final Chronic Value

Aquatic MaximumValue

Final Acute Value

Year

PFOS 0.011 0.012 140 780 1,600 2014

PFOA 0.42 12 880 7,700 15,000 2010/11

State groundwater cleanup values

Compound Groundwater -Drinking Water Pathway (mg/l)

Soil –Drinking Water Pathway (mg/kg)

Groundwater – GSI* Pathway (mg/l)

Soil – GSI* Pathway (mg/kg)

Year

PFOS 0.07 - 0.012 0.24 2018

PFOA 0.07 - 12 10,000 2018

PFOS + PFOA 0.07 - - 2018

Michigan PFAS Response: public health focus

Overwhelming focus is on human health protection, so DHHS is involved.

Dept. of Health and Human Services:

• Public health authority, no promulgated standards, but policy action levels.

• MDEQ working closely with DHHS.

• DHHS has been developing “decision trees” for sites with PFAS groundwater

impacts.

Michigan PFAS Response: public health focus

Any PFAS detected in

res well?

PFOA+PFOS ≥ 1500 ppt?

NO

No public health recommendations for

PFAS.

• Suggest: follow-up sampling to assess long-term conditions.

• Suggest: continue assessing potential for GW contamination in area.

NO

YES

Recommend monitoring DW and/or GW to

determine if concentrations are

increasing over time, orrecommend POU filter

as a presumptive interim measure until plume is

defined.

• Recommend: continue assessing potential for GW contamination in area.

YES

NO

Advise alternative water source or POU

filter as interim measure and seek new permanent

water source as long-term measure.

• Advise: Continue assessing potential for GW contamination in area.

YES

Advise alternative water source or

whole-house filter with monitoring as

interim measure and seek new permanent water source as long-

term measure.

• Advise: Continue assessing potential for GW contamination in area.

Total PFAS ≥ 70 ppt?

PFOA+PFOS ≥ 70 ppt?

NORecommend

POU filter as a presumptive

interim measure until plume is

defined.

• Recommend: continue assessing potential for GW contamination in area.

YES

Michigan PFAS Response – What’s Next?

Further investigations by EGLE:

• Municipal WWTP biosolids:– Data collection by State, initiated in October 2018

– PFAS standards for land application?

• Fire departments– State issued RFP on May 15, seeking contractor “for the collection, consolidation and disposal of

6% Class B aqueous film forming foam (AFFF)”.

– Fire departments can continue using Class B foam, but are required to report use via the State’s

Pollution Emergency Alerting System (PEAS) hotline.

• Site Investigations– EGLE has begun sending “compliance communications” under Part 201 for PRPs to investigate

PFAS

– Also planning to require investigation at RCRA sites (likely to include landfills)

Michigan PFAS Response – What’s Next?

New screening levels from the Department of Health and Human Services:

Lower screening levels for PFOA/PFOS and new screening levels for other PFAS could trigger more investigation and response actions.

PFAS Compound DHHS drinking water screening level

PFOA 9 ppt

PFOS 8 ppt

PFBS 1,000 ppt

PFHxS 84 ppt

PFNA 9 ppt

Regulatory Updates

USEPA PFAS Action Plan (Feb. 2019):

• Establish drinking water MCLs for PFOS & PFOA.

• Designate PFOS & PFOA as “hazardous substances” under federal law.

• “Consider” adding PFAS to Toxics Release Inventory (TRI).

• “Propose” nationwide drinking water monitoring for PFAS.

• New lab methods (coming up)

• Plan has been widely criticized for lack of schedule & specific actions.

Regulatory Updates

New drinking water standards for Michigan:

• Governor Whitmer directed the MDEQ to start rulemaking for PFAS maximum

contaminant levels (MCLs) on March 26, 2019.

• Recommendations for MCLs are due July 1, 2019.

• Must consider:– PFOA

– PFOS

– PFBS

– PFHxS

– PFNA

• Proposed regulations by October 1, 2019 (could be finalized in 2020).

• Prediction: once MCLs are promulgated, they will be adopted as GW cleanup stds.

Technical Updates

New lab methods for PFAS analysis (USEPA lead):

• Non-potable waters – direct injection (Method 8327)

– Groundwater, surface water, storm water

– Expected to be available for public review in summer 2019

• Non-potable waters – solid phase extraction/isotope dilution (Method 8328)

– Groundwater, surface water, storm water

– Also applicable for solid matrices (soil, sediment)

– USEPA plans to add compounds to the “list of 24”

– External validation planned summer 2019

• Probable finalization in first half of 2020

Other Sources of Information

Interstate Technology & Regulatory Council (ITRC)

www.itrcweb.org

• Fact sheets, training opportunities

National Groundwater Association

www.ngwa.org

• Guidance document – currently under revision

LimnoTech

www.limno.com

• Web article series – follow us on Twitter & LinkedIn

http://www.itrcweb.org/

http://www.ngwa.org/

http://www.limno.com/

Questions?

Scott Bell, P.E.

[email protected]

734-332-1200

@LimnoTech

www.limno.com

@ScottBell_Limno

www.linkedin.com/in/ScottBell-LimnoTech

mailto:[email protected]

http://www.limno.com/

pfas: like nothing we’ve seen before

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