U.S. Environmental Protection Agency
Risk-Based Prioritization Document

September 2008

Initial Risk-Based Prioritization of High Production Volume Chemicals

Sponsored Chemical
3-Methyl benzonitrile (CASRN 620-22-4)

(9th CI and CA Index Name: Benzonitrile, 3-methyl-)

Supporting Chemical
Benzonitrile (CASRN 100-47-0)

This document is based on screening-level characterizations done by EPA on the environmental
fate, hazard, and exposure of the listed chemical. The information used by EPA includes data
submitted under the HPV Challenge Program1 and the 2006 Inventory Update Reporting (IUR)2,
and data publicly available through other selected sources3. This screening-level prioritization
presents EPA's initial thinking regarding the potential risks presented by this chemical and future
possible actions that may be needed. These initial characterization and prioritization documents
do not constitute a final Agency determination as to risk, nor do they determine whether
sufficient data are available to characterize risk. Rather, they are interim evaluations.
Recommended actions may be considered by EPA in the future based on a relative judgment
regarding this chemical in comparison with others evaluated under this program, and in light of
the uncertainties presented by gaps in the available data that may be determined to exist. These
evaluations contribute to meeting U.S. commitments under the chemicals cooperation work
being done in North America4 through the EPA Chemical Assessment and Management Program
(ChAMP)5.

This chemical was considered in 2007 to have met the HPV Challenge Program guidance for a
closed-system intermediate, a chemical manufactured and processed only in closed systems to
produce other chemicals. Because closed-system intermediates have a limited potential for
exposure generally attributable only to isolated accidental releases, toxicity testing elements in
the HPV Challenge Program were reduced for those chemicals, and consisted of the Screening
Information Data Set (SIDS) minus the tests for repeated-dose toxicity and reproductive toxicity,
but including a developmental toxicity test6. The sponsor did not provide all of the elements of
this reduced data set for this chemical.

Hazard and Fate Summary:

• Human Health: The acute oral toxicity of this chemical is low. This chemical did not
induce gene mutations. It is slightly irritating to rabbit skin and severely irritating to
rabbit eyes. Developmental toxicity data and chromosomal aberration tests for genetic

1	US EPA, HPV Challenge Program information: http://epa. gov/hpv/.

2	US EPA, IUR information: http://www.epa.gov/oppt/iur/index.htm.

3	US EPA, Information on additional public databases used: http://www.epa.gov/hpvis/pubdtsum.htm.

4	US EPA, U.S. Commitments to North American Chemicals Cooperation:

http://www.epa.gov/hpv/pubs/general/sppframework.htm.

5	US EPA, ChAMP information: http://www.epa. gov/champ/.

6	US EPA, Guidance for Testing Closed System Intermediates:
http://www.epa.gov/chemrtk/pubs/general/closed9.htm.

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U.S. Environmental Protection Agency
Risk-Based Prioritization Document

September 2008

toxicity were not submitted, and were identified as a data gap under the HPV Challenge
Program.

•	Environment: The acute aquatic toxicity of 3-methylbenzonitrile to fish, aquatic
invertebrates and plants is expected to be low based on data for the supporting chemical
benzonitrile (CAS No. 100-47-0).

•	Persistence and Bioaccumulation:

o Available data indicate that this chemical is expected to have low persistence,
o Available data indicate that this chemical has low bioaccumulation potential.

Exposure Summary:

•	Both Confidential Business Information (CBI) and non-confidential information from
IUR and other sources were used in developing this initial prioritization.

•	Production Volume: No IUR reports were submitted on this chemical in 2006, so the
current production volume is unknown. The lack of IUR reports indicates that the
chemical was not manufactured or imported at or above 25,000 pounds at any single site
in 2005. It was included in the HPV Challenge program because it was reported at HPV
levels in earlier years.

•	Uses: Information submitted as part of the HPV Challenge Program indicates that this
chemical is used as a chemical process intermediate in the synthesis of a fungicide. No
information on commercial/consumer uses was found in the Hazardous Substances Data
Bank.

•	General Population and Environment: EPA identifies a low potential that the general
population or the environment might be exposed to this chemical.

•	Workers: EPA identifies a low relative ranking for potential worker exposure.

•	Consumers: EPA identifies a low potential that consumers might be exposed.

•	Children: EPA identifies a low potential that children might be exposed.

Risk Characterization Summary:

EPA reviewed the information in the HPV submission for this chemical, and determined that it
met the guidance for a closed-system intermediate. Therefore, there is a low concern for
potential risk to aquatic organisms and the general population from environmental releases, and
also to workers, consumers, and children.

•	Potential Risk to Aquatic Organisms from Environmental Releases: LOW CONCERN.

•	Potential Risk to the General Population from Environmental Releases: LOW
CONCERN.

•	Potential Risk to Workers: LOW CONCERN.

•	Potential Risk to Consumers from Known Uses: LOW CONCERN.

•	Potential Risk to Children: LOW CONCERN.

Regulatory and Related Information Summary:

•	This chemical is listed on the TSCA Inventory. It is not otherwise regulated under
TSCA.

Assumptions and Uncertainties:

•	EPA assumes that potential exposures are very limited, based on the reported use.

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•	EPA assumes that standard industrial hygiene practices would address any potential
irritation exposure to eyes and skin attributable to accidental occupational releases.

•	The HPV Challenge Program allowed for a reduced set of testing for chemicals that
qualified as closed-system intermediates, reflecting the information needed to evaluate
the hazards in the event of an accident. For two of the required endpoints, data were not
provided. Accordingly, the potential for chromosomal aberrations and developmental
toxicity cannot be determined on the basis of the available data.

Rationale Leading To Prioritization Decision:

•	The manufacture and processing of this chemical only as an intermediate to produce
other chemicals in systems that may reduce significantly the potential for worker
exposure and environmental releases leads to a low concern for risk.

•	The absence of 2006 IUR reports on this chemical suggests that its current production
and importation volume is low.

•	Accidental releases remain a partially uncharacterized potential concern because the
potential for chromosomal aberrations and developmental toxicity have not been
determined. The potential that an accidental release may occur cannot be determined
from the available information.

Prioritization Decision:

•	LOW PRIORITY - No further action suggested at this time.

•	This decision is based on the very low perceived potential for exposure to all populations,
despite the lack of characterization on certain potential hazards. The voluntary
completion of the outstanding, unsatisfied HPV Challenge Program data elements to
permit the characterization of these hazards, or the voluntary submission of information
documenting the low production volume suggested by the absence of IUR reports during
the 2006 IUR cycle, could further resolve these potential concerns.

•	EPA may consider revisiting this prioritization decision if future IUR reports indicate an
increase in production or importation volume.

Supporting Documentation:

Screening-Level Risk Characterization: September 2008
Screening-Level Hazard Characterization: September 2008
Screening-Level Exposure Characterization: September 2008

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