2014/2015 Health Risk Limit
Rules Amendments
Sarah Johnson, PhD
Nancy Rice, MPH
Minnesota Department of Health
August 7, 2014
Presentation Overview
 What is an HRL?
 Rule Amendment history
 Health-Based Guidance development
process
– How are chemicals selected for review?
– How are guidance values derived?
 2014/2015 Proposed Amendments
– New guidance
– Updated guidance
 Rule Amendment status
2
Health-Based Guidance
 A health-based guidance value, including
a Health Risk Limit (HRL), is the
concentration of a contaminant, or
mixture of contaminants, in water that is
likely to pose little or no risk to human
health, including vulnerable
subpopulations, if consumed for one day
or up to a lifetime.
 Expressed as microgram (µg) of a
contaminant per liter (L) of water, shown
as µg /L
3
MDH Health-Based
Guidance
Risk
Assessment
Advice
(RAA)
No Rulemaking
Remains
RAA
HealthBased Value
(HBV)
Not In
Groundwater
(or other)
No Rulemaking
Remains
HBV
In
Groundwater
Rulemaking
Health Risk
Limit (HRL)
4
Presentation Overview
 What is an HRL?
 Rule Amendment history
 Health-Based Guidance development
process
– How are chemicals selected for review?
– How are guidance values derived?
 2014/2015 Proposed Amendments
– New guidance
– Updated guidance
 Rule Amendment status
5
History
 Groundwater Protection Act, 1989
– 1993/94 HRLs
 Health Standards Statute, 2001
 Additional legislation
– Water Levels Standard, 2007
– PFC expedited rulemaking, 2007
6
History
Two year cycle:
 2008 HRL rule amendments (including
methodology changes), finalized 2009
 2010 HRL rule amendments, finalized
2011
 2012 HRL rule amendments, finalized
2013
 2014 HRL rule amendments, in progress
7
Rule-eligible Guidance Values
 About 12-14 chemicals anticipated
 Health-Based Guidance Values
developed during 2012-2014
 Chemical must have been detected in
groundwater, except triclosan
8
Rule-eligible Guidance Values
Triclosan
 2013 Session Law, Article 2, Section 8 (a)
 MDH required to accelerate development
of health risk limits, including triclosan…
9
Rule Amendment Status
Governor’s Office
Preliminary Review
Request for
Comments
August
2014
Rules and SONAR
Development
Notice of Intent to
Adopt Rules
Public Hearing
Estimated fall 2014
(or later)
No Hearing
Administrative Law
Judge Review
Governor’s Office
Review
Adopt Rules
10
Presentation Overview
 What is a HRL?
 Rule Amendment history
 Health-Based Guidance development
process
– How are chemicals selected for review?
– How are guidance values derived?
 2014/2015 Proposed Amendments
– New guidance
– Updated guidance
 Rule Amendment status
11
Health Risk Assessment
 Health-based water guidance developed
by two programs
– Health Risk Limit Program (HRL)
– Drinking Water Contaminants of Emerging
Concern (CEC)
12
How are chemicals selected?
 HRL program
– Interagency nominations
– Annual meeting with
• Minnesota Department of Agriculture
• Minnesota Pollution Control Agency
• Minnesota Department of Health
– Nominations and prioritization are
discussed at the meeting
13
How are chemicals selected?
 Drinking Water CEC program
– Nominations welcomed from anyone
– Submit through CEC web page, phone or
email
• Nominate Chhemicals
http://www.health.state.mn.us/divs/eh/risk/guid
ance/dwec/nominate.cfm
• 651-201-4899
• [email protected]
– Evaluated for eligibility
14
How are chemicals selected?
MDH evaluates and prioritizes nominated
chemicals
• Toxicological data, status of EPA or
other toxicology assessments
• Occurrence / exposure data
• Staffing
15
Health-Based Guidance
HRL (µg/L) ∝ (Toxicity) (Intake)
•Timing - sensitive life stages (e.g.,
developmental stage)
•Duration - less-than-chronic duration
•Age & duration specific intake data
16
Non Cancer HRL (nHRL)
nHRL duration [μg/L] = (RfD) x (RSC) x (Conversion Factor)
(IR duration)
RfD – Reference Dose (mg/kg-day)
RSC – Relative Source Contribution
Conversion Factor – 1000 (μg/mg)
IR – Ingestion Rate (L/kg-day) (EPA 2004, 2008)
Duration - Acute (up to 24 hrs), Short-term (up to 30 days),
Subchronic (up to 10% of a lifetime) & Chronic
(>10% of a lifetime) (EPA 2002)
17
Cancer HRL (cHRL)
cHRL [μg/L] =
[(SF x ADAF<2 yr x IR<2yr
(1E-5) x (100 ug/mg)
x 2) + (SF x ADAF2-<16 yr x IR2-<16yr x 14) + (SF x ADAF16+ yr x IR16+yr x 54)] / 70
SF – Slope Factor (mg/kg-day)-1
ADAF – Age Dependent Adjustment Factor (EPA 2005)
(<2 yr – ADAF = 10, 2 - <16 yr – ADAF = 3, & 16> yr – ADAF = 1)
IR – Ingestion Rate (L/kg-day) (EPA 2004, 2008)
18
Health Risk Assessments
 Three Levels of Review
– Primary
• Information compilation
• Data evaluation
• Qualitative/quantitative assessment
– Secondary
• Re-evaluation and assessment
• Discussion with primary reviewer
– Team Review
• Conclusions and rationale discussed
• Resolution of scientific judgment issues
19
HRLs in Context

If a non-cancer guidance value for a longer duration is
higher than the value for a shorter duration, the longer
duration value is set equal to the shorter duration value
Example:
⁻
⁻

Calculated Short-term Value = 100 µg/L
Calculated Chronic Value = 200 ug/L, set to 100 µg/L
MDH recommends a newer HBV or RAA over using an
older HRL
⁻ May result in dual guidance

MDH will replace older HBVs with promulgated HRLs
20
Presentation Overview
 What is a HRL?
 Rule Amendment history
 Health-Based Guidance development
process
– How are chemicals selected for review?
– How are guidance values derived?
 2014/2015 Proposed Amendments
– New guidance
– Updated guidance
 Rule Amendment status
21
New MDH Guidance
(No previous HRL)
 Bentazon
 Bisphenol A
 Dimethenamid
 Dimethenamid-p
 Sulfamethazine
 Triclosan
22
Bentazon
(CAS # 25057-89-0)




Use: Pesticide (herbicide)
Lowest guidance value: 30 μg/L
Endpoint: Thyroid
Occurrence: Some MN drinking water wells
and some surface water.
 Concentration example: Found <1 μg/L in
some waters but up to 440 μg/L at a clean-up
site (MDA/MDH data).
 Requested by: State Interagency nomination
23
Bisphenol A
(CAS # 80-05-7)




Use: Epoxy resin and polycarbonate plastics
Lowest guidance value: 20 μg/L
Endpoint: Liver system, kidney system
Occurrence: Found in wells, especially near
landfills.
 Concentration example: A maximum
concentration of 4.4 μg/L in a well (USGS,
2014).
 Requested by: CEC nominations (NGO, Two state
agencies)
24
Dimethenamid (CAS # 87674-68-8)
Dimethenamid-p (CAS # 163515-14-8)





Use: Pesticide (herbicide)
Lowest guidance value: 300 μg/L
Endpoint: Liver system
Occurrence: Drinking water wells
Concentration examples: In 2012, maximum
detections of 0.89 μg/L (MDA, 2013). In 2013,
maximum detections of 0.357 μg/L (MDA,
2014).
 Requested by: State Interagency nomination
25
Sulfamethazine (CAS # 57-68-1)





Use: Antibiotic
Lowest guidance value: 100 μg/L
Endpoint: Thyroid
Occurrence: Wells
Concentration example: Maximum of 0.040
μg/L (USGS, 2014).
 Requested by: CEC nomination (State
agency)
26
Triclosan (CAS # 3380-34-5)
 Use: Antimicrobial
 Lowest guidance value: 50 μg/L
 Endpoint: Thyroid (E), Female reproductive
system
 Occurrence: Surface water
 Concentration examples: 4.3 μg/L in
wastewater and 0.31 μg/L in streams (MDH,
2014).
 Requested by: CEC nomination (State
agency)
27
Updated MDH Guidance
 Butyl Benzyl Phthalate  Pentachlorophenol
 Cadmium
 1,1,2Trichloroethylene
 Di (2-ethylhexyl)
phthalate
 Dibutyl phthalate
28
Butyl Benzyl Phthalate (CAS# 85-68-7)





Use: Plasticizer: flexibility in plastics
Lowest new guidance value: 100 μg/L
1993 HRL chronic value: 100 μg/L
Endpoint: Developmental (E)
Occurrence: Landfill leachate, leaking
underground storage tanks
 Concentration example: 5 μg/L in a
monitoring well in 2004 (MPCA data).
 Requested by: CEC nomination (State agency)
29
Cadmium (CAS # 7440-43-9)
 Use: Naturally occurring metal. Used in
batteries, paints, inexpensive jewelry, toys
 Lowest guidance value: 0.5 μg/L
 1993 HRL chronic value: 4 μg/L
 Endpoint: Renal (kidney) system, Skeletal
 Occurrence: Naturally occurring, and in
groundwater impacted by landfill leachate or
other contamination.
 Concentration example: Up to 4.4 μg/L in
groundwater in 1997 (MPCA data).
 Requested by: State Interagency nomination, CEC
nomination (State agency)
30
Di (2-ethylhexyl) phthalate (CAS# 117-81-7)





Use: Plasticizer: flexibility in plastics
Lowest guidance value: 7 μg/L
MCL-HRL chronic value: 6 μg/L
Endpoint: Cancer
Occurrence: Found in landfill leachate or
areas affected by leaking tanks.
 Concentration example: 1.6 μg/L
in a well in 2008 (MPCA contractor’s data).
 Requested by: CEC nomination (State agency)
31
Dibutyl phthalate (CAS# 84-74-2)





Use: Plasticizer: flexibility in plastics
Lowest guidance value: 20 μg/L
1993 HRL chronic value: 700 μg/L
Endpoint: Developmental (E)
Occurrence: Found in landfill leachate or
areas affected by leaking tanks.
 Concentration example: 5.6 μg/L in a
monitoring well in 2004 (MPCA data).
 Requested by: CEC nomination (State agency)
32
Pentachlorophenol (CAS# 87-86-5)





Use: Pesticide, preservative, and disinfectant
Lowest guidance value: 0.3 μg/L
MCL-HRL chronic value: 1 μg/L
Endpoint: Cancer
Occurrence: Groundwater at contaminated
sites throughout MN
 Concentration example: 8000 μg/L or more at
some sites historically. In recent years,
concentrations have been below 0.3 μg/L
(MDH, 2013).
 Requested by: State Interagency nomination
33
1,1,2-Trichloroethylene
(TCE) (CAS# 79-01-6)





Use: Solvent, degreaser
Lowest guidance value: 0.4 μg/L
MCL-HRL chronic value: 5 μg/L
Endpoint: Developmental, Immune
Occurrence: Groundwater at several sites in
MN.
 Concentration example: As high as 40 μg/L
in a well in 2012 (MDH/MPCA data).
 Requested by: State Interagency nomination
34
Presentation Overview
 Rule Amendment history
 Health-Based Guidance development
process
– What is a HRL?
– How are guidance values derived?
 2012 Proposed Amendments
– New guidance
– Updated guidance
 Rule Amendment status
35
Possible additional chemicals
 Acrylamide
 Acetaminophen
 Other chemicals currently under review:
– cis-1,2-Dichloroethylene (solvent)
– Nonylphenol (surfactant)
– Venlafaxine (pharmaceutical)
36
Rule Amendment Status
Governor’s Office
Preliminary Review
April 14,
2014
Request for
Comments
August
2014
Rules and SONAR
Development
Notice of Intent to
Adopt Rules
Public Hearing
Estimated fall 2014
(or later)
No Hearing
Administrative Law
Judge Review
Governor’s Office
Review
Adopt Rules
37
Commenting on Proposed Rules
Two comment periods:
1) Request for Comments
–
–
–
–
–
Current, ongoing
Oral or written
Helps MDH be aware of concerns, new data
Easier for MDH to make changes when needed
Ends with publication of Notice of Intent to Adopt
Rules
38
Commenting on Proposed Rules
2) Notice of Intent to Adopt rules
–
–
–
–
–
Stricter timeline: 30 days
Must be in writing
Comments become part of official record
Included in material for Administrative Law Judge
More difficult and costly for MDH to make
evaluations and changes
39
MDH Resources
 MDH Guidance Values Table (including links
to toxicological summaries)
Human Health-Based Water Guidance Table
(http://www.health.state.mn.us/divs/eh/risk/guid
ance/gw/table.html)
 2014 MDH Rule Amendment Information
2014/2015 Amendments - Overview and Links
(http://www.health.state.mn.us/divs/eh/risk/
rules/water/overview.html)
40
Questions?
41