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Bis(2-chloroisopropyl) ether
CASRN 39638-32-9
Contents
0407
Bis(2-chloroisopropyl) ether; CASRN 39638-32-9
Health assessment information on a chemical substance is included in IRIS only
after a comprehensive review of chronic toxicity data by U.S. EPA health
scientists from several Program Offices and the Office of Research and
Development. The summaries presented in Sections I and II represent a
consensus reached in the review process. Background information and
explanations of the methods used to derive the values given in IRIS are
provided in the Background Documents.
STATUS OF DATA FOR Bis(2-chloroisopropyl) ether
File On-Line 10/01/1989
Category (section) Status Last Revised
----------------------------------------- -------- ------------
Oral RfD Assessment (I.A.) on-line 08/01/1990
Inhalation RfC Assessment (I.B.) no data
Carcinogenicity Assessment (II.) no data
_I. CHRONIC HEALTH HAZARD ASSESSMENTS FOR NONCARCINOGENIC EFFECTS
__I.A. REFERENCE DOSE FOR CHRONIC ORAL EXPOSURE (RfD)
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
Last Revised -- 08/01/1990
The oral Reference Dose (RfD) is based on the assumption that thresholds exist
for certain toxic effects such as cellular necrosis. It is expressed in units
of mg/kg-day. In general, the RfD is an estimate (with uncertainty spanning
perhaps an order of magnitude) of a daily exposure to the human population
(including sensitive subgroups) that is likely to be without an appreciable
risk of deleterious effects during a lifetime. Please refer to the Background
Document for an elaboration of these concepts. RfDs can also be derived for
the noncarcinogenic health effects of substances that are also carcinogens.
Therefore, it is essential to refer to other sources of information concerning
the carcinogenicity of this substance. If the U.S. EPA has evaluated this
substance for potential human carcinogenicity, a summary of that evaluation
will be contained in Section II of this file.
___I.A.1. ORAL RfD SUMMARY
Critical Effect Experimental Doses* UF MF RfD
-------------------- ----------------------- ----- --- ---------
Decrease in hemoglobin NOAEL: 400 ppm 1000 1 4E-2
and possible erythro- (35.8 mg/kg/day) mg/kg/day
cyte destruction
LOAEL: 2000 ppm
104-Week Mouse Study (198 mg/kg/day)
Oral Exposure (diet)
Mitsumori et al., 1979
*Conversion Factors: Determined by principal investigators
___I.A.2. PRINCIPAL AND SUPPORTING STUDIES (ORAL RfD)
Mistsumori, K., T. Usui, K. Takahashi and Y. Shirasu. 1979. Twenty-four
month chronic toxicity studies of dichlorodiisopropyl ether in mice. Nippon
NoYaku Gakkaishi. 4(3): 323-335.
Bis-(2-chloroisopropyl) ether (98.5% pure) was incorporated into the diets of
SPF-ICR mice (56 males and 56 females/group) at levels of 0, 80, 400, 2000, or
10,000 ppm for up to 104 weeks. Comprehensive hematological, blood
biochemical, and urinalysis determinations were performed on 7 mice/sex/group
at 13, 26, and 52 weeks; on 6/sex/group at 78 weeks; and the remaining mice at
104 weeks. Hemosiderin deposition in the spleen was seen in the males on the
10,000 ppm diet (HDT) and in females receiving both the 2000 and 10,000 ppm
diet. Decreases in hemoglobin concentration and red blood cell counts were
also observed. These findings indicate a treatment-related increase in
erythrocyte destruction. A NOAEL of 2000 ppm for males and 400 ppm for
females was indicated. These doses were determined by the investigators to be
equivalent to 198 and 35.8 mg/kg/day for males and females, respectively. The
females were considered more sensitive to the effects of bis-(2-
chloroisopropyl) ether in the diet and the NOAEL of 400 ppm (35.8 mg/kg/day)
was considered appropriate.
All other available studies on bis-(2-chloroisopropyl) ether were conducted
using an isopropyl isomer mixture containing only 70% of the bis-(2-
chloroisopropyl) ether. Accordingly, none of these studies were included with
this summary.
___I.A.3. UNCERTAINTY AND MODIFYING FACTORS (ORAL RfD)
UF -- The 1000-fold uncertainty factors accounts for both interspecies and
interhuman variability in the toxicity of this chemical in lieu of specific
data. An additional uncertainty factor of 10 was indicated to account for
data gaps in the studies on bis-(2-chloroisopropyl) ether.
MF -- None
___I.A.4. ADDITIONAL COMMENTS (ORAL RfD)
None.
___I.A.5. CONFIDENCE IN THE ORAL RfD
Study -- Medium
Data Base -- Low
RfD -- Low
Confidence in the principal study is medium because an acceptable number of
animals of each sex was used, four doses were given, and many test parameters
were measured. Confidence in the data base is low because no supporting
studies were available. Accordingly, confidence in the RfD is low.
___I.A.6. EPA DOCUMENTATION AND REVIEW OF THE ORAL RfD
Source Document -- U.S. EPA, 1989
Other EPA Documentation -- None
Agency Work Group Review -- 12/18/1985, 08/13/1987, 07/20/1989
Verification Date -- 07/20/1989
___I.A.7. EPA CONTACTS (ORAL RfD)
Please contact the Risk Information Hotline for all questions concerning this
assessment or IRIS, in general, at (513)569-7254 (phone), (513)569-7159 (FAX)
or RIH.IRIS@EPAMAIL.EPA.GOV (internet address).
__I.B. REFERENCE CONCENTRATION FOR CHRONIC INHALATION EXPOSURE (RfC)
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
Not available at this time.
_II. CARCINOGENICITY ASSESSMENT FOR LIFETIME EXPOSURE
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
This substance/agent has not undergone a complete evaluation and determination
under US EPA's IRIS program for evidence of human carcinogenic potential.
_VI. BIBLIOGRAPHY
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
Last Revised -- 08/01/1991
__VI.A. ORAL RfD REFERENCES
Mitsumori, K., T. Usui, K. Takahashi and Y. Shirasu. 1979. Twenty-four
month chroni c toxicity studies of dichlorodiisopropyl ether in mice. J.
Pesticide Sci. 4: 323-335.
U.S. EPA. 1989. Drinking Water Health Advisory for Bis-(2-chloroisopropyl)
ether, Office of Drinking Water, Washington, DC. (Draft)
__VI.B. INHALATION RfD REFERENCES
None
__VI.C. CARCINOGENICITY ASSESSMENT REFERENCES
None
_VII. REVISION HISTORY
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
-------- -------- --------------------------------------------------------
Date Section Description
-------- -------- --------------------------------------------------------
10/01/1989 I.A. Oral RfD summary on-line
10/01/1989 VI. Bibliography on-line
11/01/1989 All CASRN corrected
08/01/1990 I.A. Text edited
08/01/1990 III.A. Health Advisory on-line
08/01/1990 VI.D. Health Advisory references added
08/01/1991 VI.A. Mitsumori reference clarified
01/01/1992 IV. Regulatory Action section on-line
VIII. SYNONYMS
Substance Name -- Bis(2-chloroisopropyl) ether
CASRN -- 39638-32-9
Last Revised -- 10/01/1989
39638-32-9
Propane, 2,2'-oxybis(2-chloro-
BIS(2-CHLOROISOPROPYL) ETHER
HSDB 6007
2,2'-Oxybis(2-chloropropane)
Last updated: 5 May 1998
URL: http://www.epa.gov/iris/SUBST/0407.HTM
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