FSTRAC's mission is to strengthen relationships and cooperation among EPA, states and tribes through
the exchange of technical information primarily regarding water-related human health and risk assess-
ment and also share information on ecological effects related to water quality criteria. FSTRAC is composed
of current representatives from governmental agencies (state, tribal, federal health and environmental
agencies, and other regulatory authorities) and representatives from the Association of State Drinking
Water Administrators (ASDWA) and the Association of Clean Water Administrators (ACWA). The goal of
FSTRAC is to share information that supports the development of well-rounded, integrated approaches to
effects assessment, risk assessment, risk management, risk communication, and standard-setting for drink-
ing water, groundwater, and surface water contaminants. Specific objectives of FSTRAC include:
	To foster cooperation, consistency, and an understanding of goals and problems in human health and
ecological risk assessment for contaminants in water.
	To allow the exchange of technical information, including toxicity/exposure data and analysis, and
methodologies and assumptions related to the development and implementation of regulations, criteria,
advisories, and other toxicity values under the Safe Drinking Water Act and the Clean Water Act, and
other state and tribal rules and policies as applicable.
	To allow the exchange of information on research priorities and results.
	To share science policy concerns regarding water-related human health and ecological risk assessment.
The purpose of this newsletter is to keep Federal-State Toxicology and Risk Analysis Committee (FSTRAC)
members up-to-date on current developments in toxicology, risk analysis, and water quality criteria and
standards. This newsletter also provides information on recent FSTRAC webinars and upcoming events. Please
share this newsletter with anyone you think might be interested in these topics. If you are interested in joining
FSTRAC, please contact the FSTRAC Co-Chairs, Dr. Shamima Akhter (Akhter.Shamima@epa.gov) or
Ms. Katie Fallace (Katie.Fallace@state.mn.us).
Recent Webinars
FSTRAC holds several webinars each year to share
information through presentations and discussions
regarding human health risk analysis and water
quality issues.
HECD Updates (presented by Ms. Elizabeth (Betsy) Behl,
H ECD/OST/OW/EPA) Ms. Behl presented an update of
EPA OST/HECD's accomplishments during 2020
in the areas of aquatic life, biosolids, nutrients,
biocriteria, and human health. She also described
EPA OST/HECD's FY2021 priorities, including
publishing the Phase I metals Cooperative Research
and Development Agreement report, holding
September 2020 FSTRAC Webinar
EPA held a FSTRAC Webinar in September 2020
during which the following topics were discussed:

additional regional workshops on aquatic life criteria,
holding a National Biosolids Meeting, publishing the
next biosolids biennial review, finalizing numeric
nutrient criteria for lakes, providing technical
support to states that are interested in developing lake
criteria, publishing a draft policy for comment for
determination of hypoxia and HABs events of national
significance in fresh waters, and initiating a second
peer review of the GenX toxicity values document
before publishing the final GenX toxicity values.
Determination of Data-Derived Exposure Values and
Uncertainty Factors for the Derivation of Health Protective
Drinking Water Guideline for Manganese (presented by
Dr. Mathieu Valcke, Institut National de Sante Publique du
Quebec (INSPO)) Dr. Valcke presented information on
INSPQ's approach to drinking water guideline (DWG)
determination for manganese. He noted that INSPQ
selected the most appropriate point-of-departure of
25 mg/kg/day (from MnCl2*4H20 administered to
neonate rats through drinking water) from available
toxicological reviews. Dr. Valcke described the
uncertainty/adjustment factors applied, including
non-default adjustment factors that accounted for
human variability. He also described the rationale for
the selection of exposure factors. The final DWG
proposed for manganese is 60 (ag/L. Dr. Valcke
concluded that applying a critical review of work done
by other institutions constitutes a simple, efficient
approach to DWG derivation.
EPA's Draft Harmful Algal Bloom (HAB) and Hypoxia Events of
National Significance (HHENS) Policy (presented by Dr. Lesley
D'Anglada, OW/EPA) Dr. D'Anglada presented an over-
view of the HHENS policy. She provided background
on the Harmful Algal Blooms, Hypoxia, Research and
Control Act (HABHRCA of 1998), which describes
near and long-term comprehensive efforts to prevent,
reduce, and control HABs and hypoxia in the United
States. Dr. DAnglada discussed the new amendment
for the determination of HABs and HHENS included
in the January 2019 reauthorization of HABHRCA. As
described in the amendment, she described an "Event
of National Significance" as a HABs or hypoxia event
that had or will likely have a significant detrimental
environmental, economic, subsistence use, or public
health impact on an affected State. Dr. DAnglada
mentioned that EPA and NOAA are developing
HHENS policies for freshwaters and marine waters,
respectively. She noted that EPA published a Federal
Register Notice requesting public comments on what
to consider for determining a HHENS in freshwater in
September 2019.
Comparative Potency Evaluation for Per- and Polyfluoroalkyl
Substances (PFAS) PFAS Drinking Water Values (pre-
sented by Dr. Sandra Baird, Massachusetts Department of
Environmental Protection (MassDEP) Dr. Baird presented
information on MassDEP's comparative potency eval-
uation for PFAS drinking water values. She mentioned
that MassDEP is addressing a subgroup of 6 PFAS
(rather than individual chemicals) because multiple
PFAS are found in drinking water and these PFAS
have similar structures and health effects. Dr. Baird
noted that MassDEP has extended the EPA Health
Advisory and reference dose approach for perfluo-
rooctanoic acid (PFOA) and perfluorooctane sulfonate
(PFOS) to the 4 additional PFAS in this subgroup,
perfluorohexanesulfonate (PFHxS), perfluoronona-
noic acid (PFNA), perfluorodecanoic acid (PFDA),
perfluoroheptanoic acid (PFHpA). She described the
methods used for relative potency factor (RPF) anal-
ysis, including identifying sensitive endpoints with
a dose-response trend, using individual animal data
from the NTP 28-day bioassays, applying several
dose metrics, conducting benchmark dose modeling,
and calculating RPF using benchmark dose esti-
mates. Dr. Baird noted that the RPFs for all five of the
longer-chain subgroup of PFAS (PFOA, PFOS, PFNA,
PFHxS and PFDA) were within a factor of five (and
most were within a factor of two) of PFOA.
FSTRAC Newsletter ~ Spring 2021

Information from States Developing Guidance for Specific Chemicals
Criteria Values
Minnesota Department of Health (MDH)
The Minnesota Department of Health has recently
completed water guidance for lH-benzotriazole,
tolyltriazole, 5-methyl-lH-benzotriazole, benzophe-
none, biphenyl, cyanazine and atrazine chlorinated
degradates, 1,4-dichlorobenzene, fomesafen, hydroxy-
atrazine degradates, tris(2-butoxyethyl)phosphate
(TBEP). Chemicals currently under full toxicology
review by MDH include: 1,2-dichloropropane;
n-hexane, PFHxA, 1,2-dibromomethane, and total
petroleum hydrocarbons (TPH).
MDH's program to re-evaluate existing water guid-
ance values has recently completed reviews of toluene,
trans, 1,2-dichloroethane and PFOA. The re-eval-
uation resulted in lowering the guidance values for
toluene and trans, 1,2-dichloroethane but did not
change the value for PFOA. The cancer classification
for PFOA did change as a result of the re-evaluation.
In addition, as of August 2020 MDH began using the
water intake rates presented in the 2019 update of US
EPA Exposure Factors Handbook, Chapter 3.
More detailed information on MDH water guidance
values can be found on MDH's Human Health-
Based Water Guidance Table website at https://www.
Massachusetts Department of Environmental
Protection (MassDEP)
In October 2020, the MassDEP promulgated a
Massachusetts Maximum Contaminant Level
(MMCL) of 20 ng/L for a group of six per- and
polyfluoroalkyl substances (PFAS), including perflu-
orooctane sulfonic acid (PFOS), perfluorooctanoic
acid (PFOA), perfluorohexane sulfonic acid (PFHxS),
perfluorononanoic acid (PFNA), perfluoroheptanoic
acid (PFHpA), and perfluorodecanoic acid (PFDA),
collectively termed "PFAS6". When all or some of
these six compounds occur together in drinking
water, the detected concentrations for these PFAS
should be summed and compared to the PFAS6 value
of 20 ng/L. This value is also applicable to the indi-
vidual compounds. The toxicological basis of this
MMCL is discussed in MassDEP's Office of Research
and Standards (ORS) assessment at https://www.mass.
download. To be protective of shorter-term effects
associated with these compounds, particularly devel-
opmental effects, the PFAS6 MMCL is violated when
the average of three months of PFAS6 concentrations
exceeds 20 ng/L within the same quarter (for instance,
Quarter 2 includes April, May and June) or if PFAS6
concentrations from one or two months would cause
the quarterly average to exceed 20 ng/L. For addi-
tional information on the PFAS6 MMCL and PFAS
in Massachusetts, please see https://www.mass.gov/
Technical Information
EPA's Guidelines for Human Exposure
EPA has developed updated Guidelines for Human
Exposure Assessment (hereafter "Guidelines") that
present the current policies and practices of expo-
sure assessors across the Agency. These Guidelines
replace and supersede the Guidelines for Exposure
Assessment, which were published in 1992. The
updates include a greater emphasis on formal plan-
ning, scoping, and problem formulation for exposure
assessments; advances in the evaluation of exposure
data and data quality; information on computational
exposure models  with a focus on probabilistic
models; a more rigorous consideration of uncertainty
and variability in exposure estimates; improvements
to communication with stakeholders; and, involving
tribes in scoping exposure assessments related to
tribal concerns. Guidance is also provided on pre-
senting the results of the exposure assessment and
characterizing uncertainty. Although these Guidelines
focus on exposures of humans to chemical substances,
much of the guidance also pertains to assessing wild-
life exposure to chemicals, or human exposures to
biological, noise or radiological agents.
FSTRAC Newsletter ~ Spring 2021

Status of Chapters in EPA's Exposure Factors
Handbook (2011 Edition)
The latest edition of the Exposure Factors Handbook
was published in 2011, but since October 2017, EPA
has begun to release chapter updates individually.
This new process allows risk assessors to get the
latest information as new data becomes available.
Recent updates include Chapter 3. Ingestion of Water
and Other Select Liquids, Chapter 5. Soil and Dust
Ingestion, Chapter 9. Intake of Fruits and Vegetables,
Chapter 11. Intake of Meats, Dairy Products, and Fats,
Chapter 12. Intake of Grain Products, and Chapter 19.
Building Characteristics. More information on indi-
vidual chapters can be found here: https://www.epa.
Risk Assessment
EPA's Chemical Safety for Sustainability National
Research Program
The Environmental Protection Agency's (EPA)
Office of Research and Development (ORD) con-
ducts high-quality, innovative research to provide
data, tools, models and information designed to
inform risk-based decisions about chemicals. Under
its Chemical Safety for Sustainability (CSS) National
Research Program, ORD is developing new approach
methodologies to accelerate the pace of chemical
assessment. Our CSS program is a hub of global
scientific expertise and leadership in many areas,
such as computational toxicology and exposure,
high-throughput toxicology, and complex systems sci-
ence. This research supports the Agency, states, tribes,
and other stakeholders in fulfilling their shared objec-
tives to protect human health and the environment.
CSS research is coordinated with other federal agen-
cies to better understand environmental chemical
fate, toxicity and exposure. For example, CSS partic-
ipates in the federal Tox 21 Consortium by providing
expertise in computational toxicology. Using a
high-throughput robotic screening system housed
at the National Toxicology Program at the National
Institute of Environmental Health Sciences, research-
ers are testing 10,000 environmental chemicals
(called the Tox21 10K library) for their potential to
disrupt biological pathways that may result in toxicity.
Screening results help the researchers prioritize chem-
icals for further in-depth investigation.
A major CSS initiative, the CompTox Chemicals
Dashboard, compiles and provides the public with
a one-stop-shop for chemical information, accessi-
ble via the web. The dashboard contains chemical
and toxicological information on over 883 thousand
chemicals. Additional information is available on
consumer products, high throughput screening data,
automated read across tools, computational toxicology
on-line resources, single chemical toxicological infor-
mation for aquatic and terrestrial species through the
ECOTOX knowledgebase, and access to all Tox21 data.
CSS research is a critical component of the work
being conducted by EPA's Office of Research and
Development to provide information on per- and
polyfluoroalkyl substances (PFAS). CSS PFAS research
is focused on robust chemical curation and a tiered
toxicity testing approach using new approach meth-
ods to prioritize PFAS for risk assessment, provide
information for toxicity modeling approaches such as
chemical read-across, and to inform future testing.
CSS works with states through the Environmental
Council of States and the Environmental Research
Institute of the States. CSS also provides informa-
tion to the states through webinars, professional and
informal meetings, searchable databases of existing
chemical information, internet available tools, Science
Matters Newsletter and direct support and collabora-
tion with individual states.
For additional information about CSS, please contact
Heidi Bethel at bethel.heidi@epa.gov or 202-566-2054.
Drinking Water
California Environmental Protection Agency
The California Environmental Protection Agency's
Office of Environmental Health Hazard Assessment
(OEHHA) has recommended to the State Water
Resources Control Board (SWRCB) a notification
level (NL) of 0.5 parts per billion (ppb) for perflu-
orobutane sulfonic acid (PFBS) in drinking water.
NLs are precautionary, nonregulatory health-based
levels for drinking water contaminants that warrant
FSTRAC Newsletter ~ Spring 2021

notification and further monitoring and assessment
when exceeded. OEHHA's NL recommendation is
based on thyroid toxicity observed in mice. Accepting
OEHHA's recommendation, SWRCB has issued an
NL of 0.5 ppb for PFBS and a response level of 5 ppb,
which is the level at which removal of a drinking
water source from service is recommended.
Minnesota Department of Health, Drinking
Water Contaminants of Emerging Concern (CEC)
The CEC Initiative is starting the processes for devel-
oping the FY22 annual workplan. During this process,
stakeholders are encouraged to submit nominations
for chemicals that have been released to, found in, or
have the potential to enter Minnesota waters and
	Pose a real or perceived health threat,
	Do not already have Minnesota human health-
based guidance, or
	Have new or changing health or exposure infor-
mation that increases the level of concern (and
may therefore warrant a reassessment of an exist-
ing guidance value).
Once CEC nominations have been received, they will
be screened for toxicity and exposure potential and
ranked. Based on the risk-based ranking and avail-
ability of toxicity information a proposed workplan
is developed. The proposed CEC workplan is shared
with stakeholders for comment and feedback.
For more information on the CEC Initiative, the nom-
ination, screening, and selection processes please visit
Chemicals that have previously been nominated to
the CEC Initiative can be found on the Nominated
Contaminants Status table (https://www.health.
Cooperative Agreement with EPA and Minnesota
Department of Health (MDH)
MDH has partnered with the U.S. Environmental
Protection Agency's Center for Computational
Toxicology and Exposure (EPA CCTE) in a continu-
ing effort to apply EPA's extensive data resources and
tools to MDH's assessment process for environmental
contaminants. This collaborative effort is currently
focused within two of MDH's initiatives: Drinking
Water Contaminants of Emerging Concern (CECs)
and Toxic Free Kids (TFK).
In the first project conducted under this cooperative
agreement, EPA staff from CCTE and related pro-
grams met with MDH to learn about MDH's process
for screening and ranking CECs. For more informa-
tion on this topic, visit MDH's CEC Initiative page.
EPA CCTE data scientists developed a workflow to
automate MDH's exposure screening process using
their own data sources and tools, as well as MDH's
existing data sources. The workflow is still under
development, with some aspects of the screening
process proving to be more readily automated than
others. If fully developed, the workflow could enable
the rapid initial screening of thousands of chemicals,
allowing MDH staff to focus more intensive efforts
on those chemicals with higher exposure potential.
Additional projects now underway under this cooper-
ative agreement include application of EPA Chemical
Dashboard data and tools to (1) MDH's assessment
and classification of potentially toxic substances in
consumer products used by children and (2) MDH's
toxicity-based screening process for contaminants
nominated to the CEC initiative.
Minnesota Department of Health (MDH),
Pesticide Rapid Assessments
MDH develops Pesticide Rapid Assessments for
pesticide contaminants that do not have MDH
water guidance or EPA MCLs. A Pesticide Rapid
Assessment is the amount of pesticide in water that
is unlikely to cause harm to people drinking the
water. They are developed through a shortened (or
rapid) review process that uses information from
an EPA Human Health Benchmarks for Pesticides
(HHBP)-linked document or a current EPA risk
assessment, if an HHBP is not available. The Pesticide
Rapid Assessment is likely to produce a lower guid-
ance value than a full MDH chemical review, as the
Pesticide Rapid Assessment incorporates conservative
measures, such as the 95th percentile infant water
intake rate and an RSC of 0.5 to calculate the value.
The Minnesota Department of Agriculture (MDA)
FSTRAC Newsletter ~ Spring 2021

requests Pesticide Rapid Assessments frequently.
Documents that more thoroughly describe MDH's
Pesticide Rapid Assessment methodology and report
the results of these assessment are available at https://
Clean Water
Flyers for Biological Assessment of Water Bodies
EPA recently released two flyers that summarize key
information found in two previously published EPA
technical documents on biological assessment of water
bodies. These flyers provide easily understandable
information for states, tribes and territories that are
considering developing and applying the methods and
processes described in the corresponding technical
documents. A brief description of these flyers, that
were developed in response to requests from state
water quality program managers and staff, is provided
Assessing Level of Technical Rigor to Support
Water Quality Management (EPA 822-F-21-002)
This flyer summarizes information from Biological
Assessment Program Review: Assessing Level
of Technical Rigor to Support Water Quality
Management (EPA 820-R-13-001). The biological
assessment program review includes an evaluation
of the critical technical elements, or components,
of a biological monitoring and assessment program
and provides a forum for agency cross-program dis-
cussions. The state program review process can help
states identify the technical strengths and limitation
of their biological assessment program and use it to
develop a plan for improvement and maintenance.
As such, the process provides detailed guidelines
and milestones by which state agencies can evaluate
and track progress in the development and imple-
mentation of their biological assessment programs.
A Practitioners Guide to the Biological Condition
Gradient: A Framework to Describe Incremental
Change in Aquatic Ecosystems
(EPA 822-F-21-001)
This flyer summarizes information from A
Practitioner's Guide to the Biological Condition
Gradient: A Framework to Describe Incremental
Change in Aquatic Ecosystems (EPA 842-R-16-
001). The Biological Condition Gradient model is
a conceptual, scientific framework for interpret-
ing biological response to anthropogenic stress. It
supports consistent interpretation of biological con-
dition independent of the specific method used to
collect data, the type of waterbody being assessed,
or the location of the waterbody. The framework is
often used in biological assessments by formalizing
expert knowledge of biological conditions in quanti-
tative models for specific aquatic systems.
Drinking Water Contaminant Occurrence
EPA's Proposed Revisions to the Unregulated
Contaminant Monitoring Rule (UCMR 5)
On March 11, 2021, EPA published the pro-
posed Revisions to the Unregulated Contaminant
Monitoring Rule (UCMR 5) for Public Water Systems
and Announcement of Public Meeting (86 FR 13846;
March 11, 2021). This action fulfills a key commitment
in EPA's PFAS Action Plan by proposing monitoring
for 29 per- and polyfluoroalkyl substances (PFAS) in
drinking water. The action also proposes monitoring
for lithium. UCMR 5 will provide EPA, states, and
communities with scientifically valid data on the
national occurrence of unregulated contaminants in
drinking water. The data set represents one of the pri-
mary sources of national occurrence data in drinking
water that EPA uses to ensure that all American's have
access to safe drinking water.
EPA invites public comments on the proposed rule.
Comments must be received on or before May 10,
2021. Please refer to the FR notice for more details
about submitting comments to Docket ID No. EPA-
HQ-OW-2020-0530 using the Federal eRulemaking
Portal: http://www.regulations.gov.
EPA will host a virtual stakeholder meeting twice
during the public comment period, on April 6, 2021
and April 7, 2021. The purpose of the meeting is to
discuss key aspects of the UCMR 5 proposal, includ-
ing monitoring requirements, analyte selection and
rationale, analytical methods, the laboratory approval
FSTRAC Newsletter ~ Spring 2021

process, and ground water representative monitor-
ing plans. For more details on the meeting and to
register, please visit https://www.epa.gov/dwucmr/
To ensure adequate time for public statements, indi-
viduals or organizations interested in making a
statement should identify their interest when they reg-
ister. We ask that only one person present on behalf
of a group or organization, that the presentation be
limited to ten minutes, and the person presenting par-
ticipate in a practice session prior to the live event.
Registrants will receive confirmations and further
webinar information via email. Questions regard-
ing webinar registration should be emailed to
Minnesota Department of Health (MDH),
Unregulated Contaminant Monitoring Project
MDH completed sampling for over 600 contami-
nants at approximately 70 public water systems in
the first phase of the Unregulated Contaminant
Monitoring Project (UCMP) in 2019. Data analysis is
currently being conducted. A final project report will
be released after the project is completed. MDH will
conduct additional sampling in 2021 with remaining
project funds. MDH will sample for perfluoroalkyl
substances (PFAS) and selected pesticides, in addition
to other contaminants. MDH will collect samples
from community water systems in both vulnera-
ble and non-vulnerable geologic settings to better
understand how susceptible various source waters
are to unregulated contaminants. Phase II sampling
will begin in the second quarter of 2021. MDH will
analyze results from both project phases to identify
trends in occurrence and distribution for individual
contaminants and contaminant classes. MDH will use
these results to inform development of health-based
guidance, ongoing and future monitoring needs, and
risk management approaches. Additional informa-
tion is available on the project website: https://www.
unregcontam .html.
Upcoming Events and Conferences
Upcoming FSTRAC Webinar
The next FSTRAC Webinar is scheduled for spring
2021. Additional details, including the date of the next
FSTRAC Webinar, will be provided to FSTRAC mem-
bers in the coming weeks.
SETAC North America Annual Meeting
SETAC will be holding its 42nd annual North
America meeting on November 14-18, 2021 in the
Oregon Convention Center in Portland, Oregon.
Additional information is provided on the SETAC
website: https://portland.setac.org/
SRA Annual Meeting - Society for Risk
SRA will be holding its annual meeting on December
5-9, 2021 in Washington, DC. Additional information
is provided on the SRA website: https://www.sra.org/
SOT Annual Meeting
SOT will be holding its annual meeting on March
27-31, 2022 in San Diego, California. Additional infor-
mation is provided on the SOT website: https://www.
ASM Microbe - American Society for
ASM will be holding its annual meeting virtually as
part of the World Microbe Forum on June 20-24,
2021. Additional information is provided on the ASM
website: https://asm.org/Events/ASM-Microbe/Home
FSTRAC Newsletter ~ Spring 2021

Additional Upcoming Events
ACWA will be holding a virtual spring conference and
exhibition on May 12-13, 2021. Additional informa-
tion is provided on the ACWA website: https://www.
ECOS will be holding a virtual meeting on September
8-10, 2021. Additional information is provided
on the ECOS website: https://www.ecos.org/
ASDWA is planning to hold its annual conference on
October 18-21, 2021 in Greenville, South Carolina.
ASDWA is currently evaluating options for this
conference and final details will be released in ear-
ly-May. Additional information is provided on the
ASDWA website: https://www.asdwa.org/event/
AWWA will be holding a webinar on "Staying
Ahead of PFAS Using AWWA's Drinking Water
Treatment for PFAS Selection Guide" on March
31, 2021. Additional information is provided
on the AWWA website: https://www.awwa.org/
NACWA will be holding Water Week 2021 on April
25-May 1, 2021 in Washington, DC. Additional
information is provided on the NACWA web-
site: https://www.nacwa.org/conferences-events/
NEWMOA will be holding a webinar on "Wastewater
as a Source of PFAS" on April 6, 2021. Additional
information is provided on the NEWMOA website:
http://www.newmoa.org/events/event. cfm?m=464
FSTRAC Newsletter ~ Spring 2021