1-Goodrum MRWA Dec072017 · Imp. Assess. Review 24(2004) ... cyanobacteria, viruses 1,2,3-TCP,...

12/10/2017

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Crossroads of Uncertainty in Science and Public Policy

Philip Goodrum, Ph.D., DABTIntegral Consulting, Inc.

37th MRWA Technical Conference - December 07, 2017

Emerging Contaminants

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WATER POLLUTION IN HOOSICK FALLS PROMPTS ACTION BY NY STATE

Overview

• What’s special about emerging contaminants?

• Federal and state initiatives

• Case studies

– Perfluoroalkyl substances (PFAS)

– 1,4 Dioxane

– 1,2,3 Trichloropropane

• Management strategies for water utilities

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Rising Trend for “EC Studies”

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0

200

400

600

800

1000

1200

1400

1600

1998 2000 2002 2004 2006 2008 2010 2012 2014 2016

Publication Year

# Publications*

Publications with “emerging contaminant” or “contaminants of emerging concern”

* Google Scholar

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41

17

6 7

EC Aknowledged Some Action Initiative ManagementProgram

EC Activity Across States

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Monitoring

Research

Regulation

Reaction

Why Now?

Common Misconceptions

1. There is a common definition.

2. Emerging contaminants are only a human health drinking water issue.

3. Science and existing risk assessment frameworks will promote consistency in regulations.

4. Regulatory action is driven by federal agencies.

5. Investigation, remediation, and NRD activities are not triggered until a standard is promulgated.

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Terms and Definitions

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• “emerging contaminant”

• “unregulated emerging contaminant”

• “unregulated microbial contaminant”

• “emerging pathogen”

• “micro organic compounds”

Arizona Water Association Conf., May 8, 2015D. Quintanar, Chair, Advisory Panel on Emerging Contaminants (APEC), Outreach and Education Committee

• “micro‐constituents”

• “trace organic contaminants”

• “endocrine disrupting compounds”

• “PPCPs”

• “EDCs”

Emerging Contaminants Defined

Pathway to environment Potential for adverse

effects Real or perceived risk Knowledge lacking or

evolving No standards New science New detection

capabilities New exposure pathways

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No Signs of Slowing Down − Chemical Products Continually Developed

Chemicals − 2004 vs. 2014*• Substances:

23 million vs. 90 million• In commerce:

7 million vs. 68 million

Pharmaceuticals**• 5,400 in development

globally (2011)• 3,400 in

development in U.S. (2013)

*Source: Daughton, C.G. 2004. Env. Imp. Assess. Review 24(2004)711-732**Source: PhRma. 2013 Profile. Biopharmaceutical Research Industry.

What Makes Something an “EC”?

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Dynamic Science

Regulatory Action

Public Perception

Stakeholder Action

Litigation

EC?

EC? EC?

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Categories & Examples

perfluorinated substances (PFOA,

PFOS), PBDE, paraffins

1,4-dioxane, BPA, nonylphenol

acetaminophen, estradiol,

sulfamethoxazole

hexavalent chromium, lead, mercury

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microplastics, tricolsan, parabens

metal oxides/elements, carbon nanotubes,

quantum dots

microbial toxins, cyanobacteria, viruses

1,2,3-TCP, lindane, gylphosate

Why Do We Care about ECs?

Public Health Protection

Changing Compliance Landscape

Cost, Schedule, Mission Impacts

Consumer Perceptions & Shareholder Expectations

Litigation Potential

Insurance Coverage Needs

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Date

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http://www.usatoday.com/story/news/nation‐now/2016/01/19/michigan‐flint‐water‐contamination/78996052/#

https://theintercept.com/2016/02/17/flint‐residents‐may‐have‐been‐drinking‐pfcs‐in‐addition‐to‐lead/

http://www.cnn.com/2016/01/13/health/flint‐michigan‐water‐crisis/index.html

http://www.hydroviv.com/water‐smarts/category/contaminants

EPA Official Resigns Amid FlintWater Contamination Crisis

12/10/2017

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Defining the Prioritization Process

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Occurrence

Toxicity

Stakeholder Engagement

Treatment

• Top-down— Industrial use/emissions data (volume

ranking)

— Pesticide usage data (loadings ranking)

— Urban areas, WWTP outfalls, CSOs

• Bottom-up— Chemical analysis (hit or miss)

— In situ assays (relative conditions)

— Groundwater monitoring data (frequency & magnitude of detects)

— Toxicity reference value/exposure ratios

— Risk perception (precautionary)

EC Regulatory Action

• International

– Canada, European Union, WHO, Asia, Stockholm Convention POPs

• United States

– Federal agencies – EPA UCMR, TSCA, FDA

– State agencies

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Risk = Exposure x Toxicity

Paracelsus“Meaningful

opportunity for risk reduction”

SDWA – Health Risk Reduction and Cost Analysis [§300g‐1 Section 1412]

CERCLA – Response Actions must be feasible

and cost‐effective [§121(a)]

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Federal Actions

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• Bill to amend SDWA

• Funding for biomonitoring

• EPA ORD cites PFAS as 1 of top 3 priorities at SOT 2017

• Augment toxicity database with high throughput tests

• This week:

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State Actions – Near-Term Focus

Source: Integral Consulting (2016)

Risk Management Framework

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UCMR Monitoring

• UCMR 1 (2001-2005): 26 contaminants



• UCMR 4 (2017-2021): testing begins Jan 2018

Source: http://www.amwa.net/sites/default/files/UCMR4StakeholderPresentations.pdf

18 are now regulated, including:• BTEX• Tetrachloroethylene (PERC)• Vinyl chloride

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TSCA – the First 10 & Beyond

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Biomonitoring Data

0

50

100

150

200

250

1st Report(1999)

2nd Report(2003)

3rd Report(2005)

4th Report(2009)

4th ReportUpdate(2015)

4th ReportUpdate(2017)

Num

ber

of C

hem

ical

s Re

port

ed In

CD

C N

atio

nal R

epor

ts

Chemical Biomonitoring Reported by CDC

Game Changers – What to Watch

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State Actions

•Move ahead of federal agencies

•Inconsistent

•Public and political pressure

TSCA reform?

•Statutory timelines

•State‐of‐the‐science risk evaluations

•Wide‐reaching impacts

Dynamic Science

•Biomonitoring

•Analytical capabilities

Litigation

•Jury or judge decisions

•Precedent setting

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State-by-State

CEC program?

Watch list?

Human health or ecological?

Calculation methods?

Regulatory status?

Toxicity data?

Occurrence data?

• States often drive action

• Differences in– Priorities / Drivers

– Funding

– Process + Tools

– Transparency

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Database State Profile

Constituent Profile

State Assessment Tools

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Science

http://www.biomonitoring.ca.gov/

29www.ITRCweb.org

Occurrence

Pathway / Fate and Transport

Toxicity

Treatment

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Occurrence Data: Example Sources

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Drinking Water

Community Surveys

UCMR (NCOD)

NORMAN EMPODAT

Ground/ Surface Water

California Geotracker

New Jersey DEP and Delaware River Basin Commission

Iowa / USGS

Fish

ECsafeSEAFOOD

Casco Bay

Blood Serum/ Urine

NHANES

State Biomonitoring

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Toxicity: Example Sources

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EPA IRIS

EPA PPRTV

Other federal, state, etc.

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33Source: Integral (2016)

2017Nationwide 70+ DWS being monitored for PFAS

EC Activity by State (2016)

EC Activity in Maine• MEDEP and MECDC

— Chemicals of Concern (COC) and Chemicals of High Concern (CHC) – Triennial Updates

— Title 38, Chapter 16-D: Toxic Chemicals in Children’s Products Act (2008)

— Priority Chemical Toxics Reduction

— Surface Water Ambient Toxics (SWAT) Monitoring

• “Strong Credible Scientific Evidence”— Reproductive/developmental toxicant, EDC, or human carcinogen

— Biomonitoring: human blood, breast milk, urine

— Exposure medium: household dust, indoor air, drinking water

— Consumer product used or present in the home

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EC Activity in Maine

• Marine & Environmental Research Institute (MERI) - PBDEs

• Flame Retardants

• PFOS in fish

• 2014 SWAT program: cyanotoxins in waterbodies

• Biomonitoring: BPA, Phthalates, NP/NPE

• Casco Bay Estuary Partnership (CBEP)

• Safe Medicine Disposal for ME (PPCPs) www.safemeddisposal.com

PFOA and PFOS

MADEP ‐ 2017Gail Lipfert, Barry Mower

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Litigation Precedents?

Source: Integral (2016)

Inactive

Limited

Active

Very Active

St. Gobain, Honeywell

Solvay Specialty Polymers

3M

3M

Carpet Manufacturers

Air Force

Air Force

Air Force

DuPont

PFAS Litigation

1,4-Dioxane Drinking Water/Groundwater Limits

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0

5

10

15

20

25

30

35

40

µg/L

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100

10

1

0.1

0.01

0.0010.005 - California (NL)

0.01 - Maine (MEG)0.03 - New Jersey (PQL)

0.05 - Connecticut (AL)0.04 - New York (EL)

0.6 - Hawaii (MCL)

5 - Washington (MCL)

7 - Minnesota (HRL)

40 - Florida (HA)

42 - Arizona (HA)

100 - EPA (DWEL)

1,2,3-Trichloropropane

AL Action Level

EL Effluent Limitation

HA Health Advisory

HRL Health Risk Level

MCL Maximum Contaminant Level

MEG Maximum Exposure Guideline

NL Notification Level

PQL Practical Quantitation Limit

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µg/L

~100,000 ‐fold difference

Isn't it the Same Math?

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Groundwater

Cw = RfD x BW x RSCDWI

MCL = Cw x MFeconomic x MFtechnical

Drinking Water

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Uncertainty & Perspectives Influence Science Policy Decisions…

Threshold Value

Relevant Studies/Data

Critical Effect

Dose‐Response

Human Equivalence Calculation

Exposure Assumptions

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…Which Complicates Risk Communication

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…Leading to Confusion & Anger from Public

43 Emerging Contaminants—Looming Issues and Lessons to be Learned

Perceived Threat is a Common Theme

• Perceptions of risk drive action

• Limited data, unknowns compensated for by conservatism

• Wildly different standards across geographies

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Perfluoroalkyl Substances (PFAS)

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Date

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Nomenclature

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OECD 2013: OECD/UNEP Global PFC Group

Nomenclature

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Non‐Polymers

Perfluorinated

Perfluoroalkyl Acids

(PFAAs)

Perfluoroalkyl Carboxylic Acids

(PFCAs; e.g., PFOA)

Perfluoroalkyl

Sulfonic Acids

(PFSAs; e.g., PFOS)Perfluoroalkane Sulfonamides

(e.g., PFOSA)

Polyfluorinated

Fluorotelomer‐Based Compounds

(e.g., FTOHs, FTSs, etc.…..)

Perfluoroalkane Sulfonamido Derivatives

(e.g., MeFOSA, EtFOSA, etc.….)

Many Others

Per- and poly-fluoroalkyl substances (PFASs)

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PFASs

Carbons PFAS AcronymC4 Perfluorobutanesulfonic acid PFBSC6 Perfluorohexanoic acid PFHxAC6 Perfluorohexanesulfonic acid PFHxSC7 Perfluoroheptanoic acid PFHpAC8 Perfluorooctanoic acid PFOAC8 Perfluorooctanesulfonic acid PFOSC9 Perfluorononanoic acid PFNAC10 Perfluorodecanoic acid PFDAC12 Perfluorododecanoic acid PFDoAC13 Perfluorotridecanoic acid PFTrDAC14 Perfluorotetradecanoic acid PFTA

Precursor Polyfluorotelomer sulfonate 8:2 FTS

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Date51

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Not Your Traditional PBT Compounds

Source: NJDEP. 2013. Perfluorinated Chemicals (PFCs) – Emerging Drinking Water Contaminants. DRBC Toxics Advisory Committee, West Trenton, NJ. Gloria Post. June 5.

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Current US GW/DW Values

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TypePromulgated Rule (Y/N/P) PFOA PFOS PFNA PFBA PFBS PFHxS PFHxA PFPeA PFHpA PFOSA PFDA PFDS

USEPA DW N 0.07 0.07

GW N 0.4* 0.4* 400

Alaska (AK) GW Y 0.40 0.40Connecticut (CT) GW N 0.07 0.07 0.07 0.07 0.07 0.07 0.07Delaware (DE) GW N 0.07 0.07

GW N 0.07 0.07 38Iowa (IA) Protected GW Y 0.07 0.07

Non-protected GW Y 0.7 1Maine (ME) DW N 0.07 0.07

GW N 0.13 0.56RW N 0.05 1.2

Michigan (MI) SW Y 0.42 0.011GW Y 0.089* 0.08*

Minnesota (MN) GW/DW N 0.035 0.027 7GW/DW N 0.035 0.027 7 9GW/DW N 0.035 0.027 7 7

Nevada (NV) DW N 667New Hampshire (NH) GW Y 0.07 0.07New Jersey (NJ) GW Y 0.010

DW P 0.013*DW P 0.014*GW Y 2

Oregon (OR) SW Y 24 300 1 300 0.2Texas (TX) GW Y 0.29 0.56 0.29 71 34 0.093 0.093 0.093 0.56 0.29 0.37 0.29Vermont (VT) GW/DW Y 0.02 0.02

Location

Concentration (µg/L)

North Carolina (NC)

0.013*

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PFOA/PFOS Values to Protect Humans from Drinking Water Risk Span an Order of Magnitude

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0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

PFOA

µg/L

0

0.1

0.2

0.3

0.4

0.5

0.6

PFOS

µg/L

Toxicology is not a precise science

What explains orders of magnitude differences in standards for the same chemical?

Threshold Value

Key Study

Critical Effect

Dose‐Response

Human Equivalence

Exposure Assumptions

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EPA Office of Water Health Advisories Compared to EPA Region Groundwater Screening;

~6 Fold Difference Due To Equations

Drinking Water Guidance:

• 0.07 ug/L (ppb) or 70 ppt

• Individually or combined sum concentrations

• Unique additive consideration for HAs

Groundwater Cleanup Guidance:

• EPA has yet to include PFOA or PFOS on their RSL table, however, the calculator DOES have the input parameters already loaded

• 0.4 ug/L or 400 ppt (residential tap water HI =1)

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Date

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“Hot Topics” Trends

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© 2015. Permission to use from Sue Chang, 3M Company

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Privileged and ConfidentialPrivileged and Confidential

• General public exposure through drinking water not significant

Human Exposure Interpretations – UCMR3

Preliminary data: October 2015

Analyte% results > MRL

% PWSw/results > MRL

PFOS 0.78 1.89

PFOA 0.98 2.16

PFNA 0.06 0.29

PFHxS 0.58 1.13

PFHpA 0.65 1.68

PFBS 0.04 0.13

PFOS

PFOA

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• Contrasts with Environmental Working Group:

– “…6.5 million Americans in 27 states are drinking water tainted….

– “…5 times higher than what’s safe to drink, according to new research…” (Grandjean and Clapp, 2015)

Human Exposure Interpretations – UCMR3

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• NJDEP: “subtraction” method, NHANES 95th percentile serum value

• USEPA Office of Water (provisional HA): 20% default

• Minnesota: 20% default

Human Exposure Interpretations –Drinking Water Regs. & Relative Source Contribution

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Human Health Toxicology:PFAS Toxicology 101

• Partitions to protein (not fat/lipids)

– Blood, liver, kidney, muscle are primary distribution target organs

• PFAAs are not metabolized

• Internal target organ concentrations are key

• Kinetics and bioaccumulation are a function of protein binding, which is NOT JUST a function of chain length (functional group, isomer shape)

• No scientific consensus on relevancy of rodent data

• Inconsistent and challenging data to interpret

• Internal to administered and animal to human extrapolations drive screening levels to ppt levels

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Human Health Toxicology:PFOA and PFOS Are Still “Emerging”

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• Wealth of data but still key data gaps – active area of research

• Weight-of-evidence for noncancer effects ONLY

– Endpoints vary by regulatory agency (no consistent decision)

– Data varies by PFAS compound, species, and gender

• Screening levels based on animal studies

– USEPA chose developmental endpoints from rodents – bone ossification, changes in puberty markers (PFOA), and decreased neonatal body weight (PFOS)

– Human data = cholesterol, thyroid, liver, metabolism/lipid endpoints

• = existing animal studies

Death

Acute

Intermediate

Chronic

Immunological

Reproductive

Developmental

Cancer

Inhalation • • • • •Oral • • • • • • • •Inhalation • • • • • •Oral • • • • • • • •

PFOA

PFOS

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Human Health Toxicology:The “Other” PFAAs

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• Significant amount of data (PFAAs)

• ARE NOT THE SAME AS PFOA and PFOS

– Effects are not related to carbon chain length per se, but rather to differential accumulation in the body; functional group matters

• Weight‐of‐evidence for noncancer effects ONLY

• Screening levels based on animal studies‐ Mostly liver or kidney effects in rodents

– Available for PFBS, PFBA, PFNA, (Texas specific = 16 PFAAs)

Ecological Toxicity:PFOA and PFOS only, Mixtures Coming

Exposure Pathways Endpoints

• Soil/sediment ingestion

• Diet

• Dermal (aquatic?)

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• Liver and kidney

• Reproduction

• Toxicity Reference Values

– Avian

– TRV exceeded at some AFFF-impacted sites

• Conder and Zhou (2016)

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Example PFOS Risk-Based Screening Criteria

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Source: Used with permission from Jason Conder, Geosyntec

Environmental Sources: Real v. Myth

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Oliaei et al. 2013. Environ Sci Pollut Res

• Surface treatment– Carpet/fabric protector

– Water proofer

• Paper and packaging– Food packaging

– Paper products

• Performance chemicals– Aqueous film‐forming foam (AFFF)

– Hydraulic fluids

– Mining and oil surfactants

– Electroplating and etching surfactants

– Household additives

– Carpet cleaners

– Cosmetics

– Etc.

– Etc.

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Environmental Sources

Wastewater Treatment Plants (WWTPs)

Landfill Leachate

Non‐Point Sources: Atmospheric Deposition

Nomenclature – Key Points

• “PFAS” means hundreds of distinct classes of compounds and should not be generalized

• AFFF related PFAS

– Perfluorinated Carboxylic Acids

– Perfluorinated Sulfonic Acids

– Polyfluorinated Fluorotelomer-based compounds

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Aqueous Film Forming Foam

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Aqueous Film Forming Foam

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Hangars and Buildings Equipment Maintenance and Testing

Emergency Response Waste Management

Photos curtesy of H. Anderson, AFCEC

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AFFF History

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AFFF Formulations

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• Electrochemical fluorination chemistry: “ECF” AFFF

– Proprietary to the 3M company

– Contains PFSAs

– 30% branched isomers

– Distribution of PFAA homologs

with odd and even chain‐lengths

• Fluorotelomer chemistry

– “Telomer” AFFF

– C8 or C6 formulations

– All linear isomers

– Only even chain lengths

– Exclusively polyfluorinated

– Biotransformation to PFCAs

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AFFF Formulations - Today• AFFF continues to be the

most effective agent currently available to extinguish flammable liquid fires

• Modern AFFFs are all based on C6 telomer formulations

– Do NOT contain PFOS or its precursors

– Should NOT contain nor degrade into PFOA

• Impurities?

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All AFFF Contains Polyfluorinated Precursors

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AFFF – Key Points

• All AFFF is a mixture

• Legacy AFFF contained or degraded into long-chain PFAAs (PFOS, PFOA)

• New C6 AFFF contains or degrades into only short-chain PFAAs (C6 or less)

– Impurities?

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17 PFOA/PFAS Cases

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Class Actions

Municipality

Personal Injury

Citizen Suit

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Human Exposure –Biomonitoring at Former Pease AFB, NH

http://www.cityofportsmouth.com/publicworks/PeaseWellPFCSamplingAprilandMay%202014.pdf

Drinking water production well results, spring 2014

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Sept. 9, 2015 http://www.dhhs.state.nh.us/dphs/documents/pediatric‐results‐presentation.pdf

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Sept. 9, 2015 http://www.dhhs.state.nh.us/dphs/documents/pediatric‐results‐presentation.pdf

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• “Restoration of the aquifer”

• Extensive monitoring and modeling of GW

• Routine monitoring of DW

• Expanded blood tests

– Using a new contract lab

• ATSDR to conduct long‐term medical surveillance for residence with elevated PFAAs in blood

Biomonitoring at Former Pease AFB, NHNext Steps

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• Measurements on behalf of residents

– PFNA, PFOS, PFOA, PFHxS

• Other data

– Gender, age, residency tenure

– Raw & finished drinking water concentrations

• Unique opportunity to “test” underlying assumptions in NJDEP calculation

Blood Serum Data – Paulsboro, NJ

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Subject Demographics

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NJDEP Assumptions vs Data


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Current Water Treatment Options

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IXGAC

Biochar

DAF

Ferrate

ISCO

MF

Flocculation

Electrocoagulation

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GAC/IX realities

GW Treatment Realities

PPT and beyond…potable use endpoints

PFAS spectrum and profile

Mixed plumes

Field proven and scalable

Residuals management challenges

Reliability/Stakeholder acceptance

Integration with overall plume management strategies

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1,4 Dioxane

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Why is 1,4 Dioxane on the short list of ECs ?

• History and Use – DoD installations– Chlorinated solvent stabilizer (e.g., 1,1,1 TCA)– Aircraft de-icing– Antifreeze

• Occurrence, Fate & Transport– Miscible in water, does not sorb, recalcitrant

• Toxicology – IRIS assessments 1988, 2010 (oral), 2013 (inhalation)– Likely human carcinogen (formerly Group B2)– Hepatotoxic and neurotoxic

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1,4-Dioxane350 – Dourson et al. (2014)77 – Alaska (GCL)50 – New York (DWS); WHO (DWG)35 – EPA (HA @ 10‐4)9.1 – Texas (PCL)4.0 – Maine (MEG)3.0 – Connecticut (AL); New Hampshire (AGQS) 1.0 – California (NL); Minnesota (HGV); EPA (DWEL)0.46 – EPA Regions (tap RSL)0.40 – New Jersey (IGWQC)0.35 – Colorado (IGWQS)0.30 – Massachusetts (ORSG); Vermont (VHA)0.25 – New Hampshire (RL)

100 ppb

1 ppb

10 ppb

0.1 ppb

Federal “Actions”

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• Analytical precision improved to 1 µg/L in 2000

– Region 9 PRG was 6.2 µg/L

• EPA RSL for residential tap water has changed three times SINCE the issuance of the final IRIS assessment:

– 0.35 changed to 0.67, then to 0.78 due to changes in BW and ingestion volumes

– then to 0.46 due to addition of the inhalation pathway for residential tap water (added inhalation due to volatilization in the shower)

• Dourson et al 2014 – established non-linear mode of actions, but agencies are slow to adopt

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Crossroads

98

Uncertain ScienceManage Risk

Risk Estimation

Cost Impact

Occurrence

Treatment Options

Toxicology/Epidemiology

Public Perception

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Moving Forward

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The Holy Grail for EC Management?

• Short-term– Prioritization approaches

– Tiered, faster assessments

– Testing and data support for users /manufacturers

– Balance precaution, cost, feasibility

• Long-term– Less chemical-by-chemical assessment

– Effective broad-spectrum predictive tools for exposure & toxicity monitoring for functional groups

Fate and Transport

Toxicity

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Philip Goodrum, Ph.D., DABTToxicologist | Senior Consultant

[email protected]

Questions?

Hard Questions

• Unknown unknowns — what haven’t we thought of ?– New class, new use, new effect, new pathway, new condition

• Known unknowns — is our target list OK?– Looking under the lamp post; is our framework adequate

• Did we drop it too soon (should we drop it now) ?– Weight of evidence, indicators

• Is it toxicologically relevant ?– Humans: biomonitoring, epidemiology

– Animals: extrapolation uncertainty

– in vitro testing: Tox21, high throughput assays

1-Goodrum MRWA Dec072017 · Imp. Assess. Review 24(2004) ... cyanobacteria, viruses 1,2,3-TCP,...

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