TSCA Section 5(a)(3) Determination for Premanufacture Notice (PMN) P-18-0285

Number: P-18-0285

TSCA Section 5(a)(3) Determination: The chemical substance is not likely to present an
unreasonable risk (5(a)(3)(C))

Chemical Name:

Specific: Butanedioic acid, 2-methylene-, polymer with 2-methyl-2-[(l-oxo-2-propen-l-
yl)amino]-l-propanesulfonic acid, sodium zinc salt; CASRN: 2220235-78-7

Conditions of Use (intended, known, or reasonably foreseen)1:

Intended conditions of use (specific): Manufacture for processing and use for odor neutralization
for pet litter and cleaning/deodorizing hard surfaces, fabrics, skin and hair, odor
neutralization for air care, and odor neutralization for waste processing and solid waste
management in paper, oil, gas, mining, agriculture, food and municipal industries,
consistent with the manufacturing, processing, use, distribution, and disposal information
described in the PMN.

Known conditions of use: Applying such factors as described in footnote 1, EPA evaluated

whether there are known conditions of use and found none.

Reasonably foreseen conditions of use: Applying such factors as described in footnote 1, EPA
evaluated whether there are reasonably foreseen conditions of use and found none.

Summary: The chemical substance is not likely to present an unreasonable risk of injury to
health or the environment, without consideration of costs or other nonrisk factors, including an
unreasonable risk to a potentially exposed or susceptible subpopulation identified as relevant by
the Administrator under the conditions of use, based on the risk assessment presented below.
EPA estimated that the new chemical substance could have limited persistence and a low
potential for bioaccumulation, such that repeated exposures are not expected to cause food-chain
effects via accumulation in exposed organisms. Based on test data the new chemical substance

1 Under TSCA § 3(4), the term "conditions of use" means "the circumstances, as determined by the Administrator,
under which a chemical substance is intended, known, or reasonably foreseen to be manufactured, processed,
distributed in commerce, used, or disposed of." In general, EPA considers the intended conditions of use of a new
chemical substance to be those identified in the section 5(a) notification. Known conditions of use include activities
within the United States that result from manufacture that is exempt from PMN submission requirements.

Reasonably foreseen conditions of use are future circumstances, distinct from known or intended conditions of use,
under which the Administrator expects the chemical substance to be manufactured, processed, distributed, used, or
disposed of. The identification of "reasonably foreseen" conditions of use will necessarily be a case-by-case
determination and will be highly fact-specific. Reasonably foreseen conditions of use will not be based on
hypothetical or conjecture. EPA's identification of conditions of use includes the expectation of compliance with
federal and state laws, such as worker protection standards or disposal restrictions, unless case-specific facts indicate
otherwise. Accordingly, EPA will apply its professional judgment, experience, and discretion when considering such
factors as evidence of current use of the new chemical substance outside the United States, evidence that the PMN
substance is sufficiently likely to be used for the same purposes as existing chemical substances that are structurally
analogous to the new chemical substance, and conditions of use identified in an initial PMN submission that the
submitter omits in a revised PMN. The sources EPA uses to identify reasonably foreseen conditions of use include
searches of internal confidential EPA PMN databases (containing use information on analogue chemicals), other
U.S. government public sources, the National Library of Medicine's Hazardous Substances Data Bank (HSDB), the
Chemical Abstract Service STN Platform, REACH Dossiers, technical encyclopedias (e.g., Kirk-Othmer and
Ullmann), and Internet searches.

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TSCA Section 5(a)(3) Determination for Premanufacture Notice (PMN) P-18-0285

and on analogous chemical substances, EPA estimates that the chemical substance has moderate
environmental hazard and potential for the following human health hazards: developmental
toxicity, blood toxicity, and immunotoxicity. EPA concludes that the new chemical substance is
not likely to present an unreasonable risk under the conditions of use.

Fate: Environmental fate is the determination of which environmental compartment(s) a
chemical moves to, the expected residence time in the environmental compartment(s) and
removal and degradation processes. Environmental fate is an important factor in determining
exposure and thus in determining whether a chemical may present an unreasonable risk. EPA
estimated physical/chemical and fate properties of the new chemical substance using data for
analogue(s) (biodegradable bio-based polymers) and data submitted for the new chemical
substance. The cations (Zinc and Sodium) were not rated for fate as they are not expected to be
food web concerns and Zinc is estimated to have high waste water treatment removal based on
EPA waste water treatment plant survey data. In wastewater treatment, the new chemical
substance is expected to be removed with an efficiency of 75% to 90% due to sorption and
biodegradation. Removal of the new chemical substance by biodegradation is high. Sorption of
the new chemical substance to sludge is expected to be moderate to strong and to soil and
sediment is expected to be strong. Migration of the new chemical substance to groundwater is
expected to be slow due to strong sorption to soil and sediment. Due to low estimated vapor
pressure and Henry's law constant, the new chemical substance is expected to undergo negligible
volatilization to air. Overall, these estimates indicate that the new chemical substance has low
potential to volatilize to air or migrate to groundwater.

Persistence : Persistence is relevant to whether a new chemical substance is likely to present an
unreasonable risk because chemicals that are not degraded in the environment at rates that
prevent substantial buildup in the environment, and thus increase potential for exposure, may
present a risk if the substance presents a hazard to human health or the environment. EPA
estimated degradation half-lives of the new chemical substance using data for analogue(s)
(biodegradable bio-based polymers). EPA estimated that the new chemical substance's aerobic
and anaerobic biodegradation half-lives are < 2 months. These estimates indicate that the new
chemical substance may have limited persistence in aerobic environments (e.g., surface water)
and anaerobic environments (e.g., sediment).

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Bioaccumulation : Bioaccumulation is relevant to whether a new chemical substance is likely
to present an unreasonable risk because substances that bioaccumulate in aquatic and/or

2	Persistence: A chemical substance is considered to have limited persistence if it has a half-life in water, soil or
sediment of less than 2 months or there are equivalent or analogous data. A chemical substance is considered to be
persistent if it has a half-life in water, soil or sediments of greater than 2 months but less than or equal to 6 months
or if there are equivalent or analogous data. A chemical substance is considered to be very persistent if it has a half-
life in water, soil or sediments of greater than 6 months or there are equivalent or analogous data. (64 FR 60194;
November 4, 1999)

3	Bioaccumulation: A chemical substance is considered to have a low potential for bioaccumulation if there are
bioconcentration factors (BCF) or bioaccumulation factors (BAF) of less than 1,000 or there are equivalent or
analogous data. A chemical substance is considered to be bioaccumulative if there are BCFs or BAFs of 1,000 or
greater and less than or equal to 5,000 or there are equivalent or analogous data. A chemical substance is considered
to be very bioaccumulative if there are BCFs or BAFs of 5,000 or greater or there are equivalent or analogous data.
(64 FR 60194; November 4 1999)

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terrestrial species pose the potential for elevated exposures to humans and other organisms via
food chains. EPA estimated the potential for the new chemical substance to bioaccumulate using
data for analogue(s) (biodegradable bio-based polymers). EPA estimated that the new chemical
substance has low bioaccumulation potential based on large molecular volume which reduces
bioavailability. EPA estimated that the new chemical substance could have limited persistence
and a low potential for bioaccumulation, such that repeated exposures are not expected to cause
food-chain effects via accumulation in exposed organisms.

Human Health Hazard4: Human health hazard is relevant to whether a new chemical substance
is likely to present an unreasonable risk because the significance of the risk is dependent upon
both the hazard (or toxicity) of the chemical substance and the extent of exposure to the
substance. EPA estimated the human health hazard of this chemical substance based on its
estimated physical/chemical properties, available data on the new chemical substance, by
comparing it to structurally analogous chemical substances for which there is information on
human health hazard, and other structural information. Absorption is expected to be nil via all
routes for the parent polymer and nil to poor via all routes for the low molecular weight fractions
based on physical/chemical properties. For the zinc cation, absorption is expected to be moderate
to good in the GI tract and lungs and nil to poor through the skin based on physical/chemical
properties. For the new chemical substance, EPA identified immunotoxicity, developmental
toxicity, and blood toxicity as hazards based on analogue data and structural information.
Submitted guideline and non-guideline tests of the new chemical substance reported the test
substance as non-mutagenic, non-irritating, and non-sensitizing. Submitted in vitro data predict
potential for harmful effects via the oral route but not via the inhalation route. EPA identified a
LOAEL of 0.91 mg/kg/day based on a sensitive biological indicator of zinc toxicity (decreased
erythrocyte Cu, Zn-superoxide dismutase activity), which was used to derive exposure route-and
population-specific points of departure for quantitative risk assessment, described below.

Environmental Hazard5: Environmental hazard is relevant to whether a new chemical
substance is likely to present unreasonable risks because the significance of the risk is dependent

4	A chemical substance is considered to have low human health hazard if effects are observed in animal studies with
a No Observed Adverse Effect Level (NOAEL) equal to or greater than 1,000 mg/kg/day or if there are equivalent
data on analogous chemical substances; a chemical substance is considered to have moderate human health hazard if
effects are observed in animal studies with a NOAEL less than 1,000 mg/kg/day or if there are equivalent data on
analogous chemical substances; a chemical substance is considered to have high human health hazard if there is
evidence of adverse effects in humans or conclusive evidence of severe effects in animal studies with a NOAEL of
less than or equal to 10 mg/kg/day or if there are equivalent data on analogous chemical substances. EPA may also
use Benchmark Dose Levels (BMDL) derived from benchmark dose (BMD) modeling as points of departure for
toxic effects. See https://www.epa.gov/bmds/what-benchmark-dose-software-bmds. Using this approach, a BMDL
is associated with a benchmark response, for example a 5 or 10 % incidence of effect. The aforementioned
characterizations of hazard (low, medium, high) would also apply to BMDLs. In the absence of animal data on a
chemical or analogous chemical substance, EPA may use other data or information such as from in vitro assays,
chemical categories (e.g., Organization for Economic Co-operation and Development, 2014 Guidance on Grouping
of Chemicals, Second Edition. ENV/JM/MONO(2014)4. Series on Testing & Assessment No. 194. Environment
Directorate, Organization for Economic Co-operation and Development, Paris, France.

(http://www.oecd.ore/officialdocuments/publicdisplavdocumentpdf/?cote=env/im/mono(2014')4&doclanguage=eh)').
structure-activity relationships, and/or structural alerts to support characterizing human health hazards.

5	A chemical substance is considered to have low ecotoxicity hazard if the Fish, Daphnid and Algae LC50 values are
greater than 100 mg/L, or if the Fish and Daphnid chronic values (ChVs) are greater than 10.0 mg/L, or there are not

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upon both the hazard (or toxicity) of the chemical substance and the extent of exposure to the
substance. EPA estimated environmental hazard of this new chemical substance using
predictions based submitted test data on an acceptable analogue and Ecological Structure
Activity Relationships (ECOSAR) Predictive Model (https://www.epa.gov/tsca-screening-
tool s/ecological -structure-acti vitv-relationships-ecosar-predicti ve-model). specifically on
polyanionic polymers. This substance falls within the TSCA New Chemicals Category of
Polyanionic Polymers. The acute toxicity values for fish, daphnia and algae are >100 mg/L
(ECOSAR), >100 mg/L (analogue data), and 1.7 mg/L (analogue data), respectively. The chronic
toxicity values for fish, daphnia and algae are >100 mg/L (ECOSAR), >100 mg/L (ECOSAR),
and 1.43 (analogue data) mg/L, respectively. These toxicity values indicate that the new
chemical substance is expected to have moderate environmental hazard. Application of
assessment factors 4 and 10 acute and chronic toxicity values, respectively, results in acute and
chronic concentrations of concern are 0.425 mg/L (425 ppb) and 0.143 mg/L (143 ppb),
respectively.

Exposure: The exposure to a new chemical substance is potentially relevant to whether a new
chemical substance is likely to present unreasonable risks because the significance of the risk is
dependent upon both the hazard (or toxicity) of the chemical substance and the extent of
exposure to the substance.

EPA estimates occupational exposure and environmental release of the new chemical substance
under the intended conditions of use described in the PMN using ChemSTEER (Chemical
Screening Tool for Exposures and Environmental Releases; https://www.epa.gov/tsca-screening-
tools/chemsteer-chemical-screening-tool-exposures-and-environmental-releases). EPA uses
EFAST (the Exposure and Fate Assessment Screening Tool; https://www.epa.gov/tsca-
screening-tools/e-fast-exposure-and-fate-assessment-screening-tool-version-2014) to estimate
general population, consumer, and environmental exposures.

EPA considers workers to be a potentially exposed or susceptible subpopulation (PESS) on the
basis of greater exposure potential compared to the general population. EPA also considers PESS
in conducting general population drinking water exposures by evaluating risks associated with
water intake rates for multiple age groups, ranging from infants to adults. EPA considers
consumers of specific products to be a potentially exposed or susceptible subpopulation on the
basis of greater exposure potential compared to the general population who do not use specific
products.

For this new chemical assessment, EPA assessed worker exposure via inhalation and dermal
routes. Releases to water, air, and landfill were estimated. Exposure to the general population

effects at saturation (occurs when water solubility of a chemical substance is lower than an effect concentration), or
the log Kow value exceeds QSAR cut-offs. A chemical substance is considered to have moderate ecotoxicity hazard
if the lowest of the Fish, Daphnid or Algae LC50s is greater than 1 mg/L and less than 100 mg/L, or where the Fish
or Daphnid ChVs are greater than 0.1 mg/L and less than 10.0 mg/L. A chemical substance is considered to have
high ecotoxicity hazard, or if either the Fish, Daphnid or Algae LC50s are less than 1 mg/L, or any Fish or Daphnid
ChVs is less than 0.1 mg/L (Sustainable Futures https://www.epa.gov/sustainable-futures/sustainable-futures-p2-
framcwork-manual).

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was assessed via drinking water and landfill leachate. Exposure to the general population via fish
ingestion and inhalation were not assessed because the new chemical substance is not expected
to bioconcentrate and releases to air were expected to be negligible (below modeling thresholds).
Exposure to consumers was assessed via inhalation and dermal routes.

Risk Characterization: EPA applies a margin of exposure approach to calculate potential
human health risks of new chemicals. A benchmark (acceptable) margin of exposure is derived
by applying uncertainty factors for the following types of extrapolations: intra-species
extrapolation (UFh = 10 to account for variation in sensitivity among the human population),
inter-species extrapolation (UFA = 10 to account for extrapolating from experimental animals to
humans) and LOAEL-to-NOAEL extrapolation (UFl = 10 to account for using a LOAEL when
a NOAEL is not available). Hence, in the New Chemicals Program, a benchmark MOE is
typically 100 and 1,000 when NOAELs and LOAELs, respectively, are used to identify hazard.
When allometric scaling or pharmacokinetic modeling is used to derive an effect level, the UFH
may be reduced to 3, for a benchmark MOE of 30. The benchmark MOE is used to compare to
the MOE calculated by comparing the toxicity NOAEL or LOAEL to the estimated exposure
concentrations. When the calculated MOE is equal to or exceeds the benchmark MOE, the new
chemical substance is not likely to present an unreasonable risk. EPA assesses risks to workers
considering engineering controls described in the PMN but in the absence of personal protective
equipment (PPE) such as gloves and respirators. If risks are preliminarily identified, EPA then
considers whether the risks would be mitigated by the use of PPE (e.g., impervious gloves,
respirator).

Risks to human health for the new chemical substances were evaluated using the route-specific
effect levels (i.e., LOAEL) described above. Risks were not identified for workers for
blood/immunotoxicity via inhalation or dermal exposures based on quantitative hazard data for a
component of the new chemical substance (zinc) (MOEinhalation = 189, MOEoermai =11;
Benchmark MOE = 3).

Risks were not identified for the general population for blood/immunotoxicity via drinking water
or groundwater ingestion (due to landfill leaching) based on quantitative hazard data for a
component of the new chemical substance (zinc) (MOEs > 1700; Benchmark MOE = 3).

Risks were not identified for consumers for blood/immunotoxicity via dermal or inhalation
exposures to cleaners or pet litter based on quantitative hazard data for a component of the new
chemical substance (zinc) (MOEDermai > 340, MOE inhalation > 17; Benchmark MOE = 3).

Risks to the environment were evaluated by comparing estimated surface water concentrations
with the estimated acute and chronic COCs. Risks to the environment were evaluated by
comparing estimated surface water concentrations with the acute and chronic concentrations of
concern (COC). Risk from acute and chronic exposure to the environment were not identified
due to releases to water that did not exceed the acute and chronic COC.

Because no unreasonable risks to workers, the general population, consumers, or the
environment were identified, EPA has determined that the new chemical substance is not likely
to present unreasonable risk to human health or the environment under the conditions of use.

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TSCA Section 5(a)(3) Determination for Premanufacture Notice (PMN) P-18-0285

7/23/2019		IsL

Date:	Tala R. Henry, Ph.D.

Deputy Director for Programs

Office of Pollution Prevention and Toxics

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