•fPfix
EPA/60O/8-9O/O25
/ September
HEALTH AND ENVIRONMENTAL EFFECTS DOCUMENT
FOR BROMOFORM
ENVIRONMENTAL CRITERIA AND ASSESSMENT OFFICE
OFFICE OF HEALTH AND ENVIRONMENTAL ASSESSMENT
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OH 45268
-------
-------
TECHNICAL REPORT DATA
(fleate read Jmtructions on the reverse before completing!
. REPORT NO.
IEPA/600/8-90/025
f4. TITLE AND SUBTITLE
Health and Environmental Effects Document for
Bromoform
3. RECIPIENT'S ACCESSION NO.
PB91-216424
6. REPORT DATE
6. PERFORMING ORGANIZATION CODE
7. AUTHOH{S>
8 PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
11. CONTRACT /GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
Environmental Criteria and Assessment Office
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati. OH 45268
14. SPONSORING AGENCY CODE
EPA/600/22
15. SUPPLEMENTARY NOTES
16. ABSTRACT
Health and Environmental Effects Documents (HEEDS) are prepared for the Office of
Solid Waste and Emergency Response (OSWER). This document series is intended to
support listings under the Resource Conservation and Recovery Act (RCRA) as well as
to provide health-related limits and goals for emergency and remedial actions under
he Comprehensive Environmental Response, Compensation and Liability Act (CERCLA).
oth published literature and information obtained from Agency Program Office files
are evaluated as they pertain to potential human health, aquatic life and environmen-
tal effects of hazardous waste constituents.
Several quantitative estimates are presented provided sufficient data are
available. For systemic toxicants, these include Reference Doses (RfDs) for chronic
and subchronic exposures for both the inhalation and oral exposures. In the case of
suspected carcinogens, RfDs may not be estimated. Instead, a carcinogenic potency
factor, or q *, is provided. These potency estimates are derived for both oral and
inhalation exposures where possible. In addition, unit risk estimates for air and
drinking water are presented based on inhalation and oral data, respectively.
Reportable quantities (RQs) based on both chronic toxicity and carcinogenicity are
derived. The RQ is used to determine the quantity of a hazardous substance for
which notification is required in the event of a release as specified under CERCLA.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/GlOUp
8. DISTRIBUTION STATEMENT
Public
IB. SECURITY CLASS (This Report/
Unclassified
21. NO. OF PAGES
117
90. SECURITY CLASS (Ttlitpage)
Unclassified
22. PRICE
EPA Farm 2220-1 (R«v, 4-77) PMKVlout BOiTiON IB OBSOLETE
-------
DISCLAIMER
This document has been reviewed 1n accordance with the U.S. Environ-
mental Protection Agency's peer and administrative review policies and
approved for publication. Mention of trade names or commercial products
does not constitute endorsement or recommendation for use.
11
-------
PREFACE
Health and Environmental Effects Documents (HEEDs) are prepared for the
Office of Solid Waste and Emergency Response (OSWER). This document series
Is Intended to support listings under the Resource Conservation and Recovery
Act (RCRA) as well as to provide health-related limits and goals for emer-
gency and remedial actions under the Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA). Both published literature and
Information obtained for Agency Program Office files are evaluated as they
pertain to potential human health, aquatic life and environmental effects of
hazardous waste constituents. The literature searched for 1n this document
and the dates searched are Included In "Appendix: Literature Searched."
Literature search material 1s current up to 8 months previous to the final
draft date listed on the front cover. Final draft document dates (front
cover) reflect the date the document Is sent to the Program Officer (OSWER}.
Several quantitative estimates are presented provided sufficient data
are available. For systemic toxicants, these Include Reference doses (RfDs)
for chronic and subchronic exposures for both the Inhalation and oral
exposures. The subchronic or partial lifetime RfD, 1s an estimate of an
exposure level that would not be expected to cause adverse effects when
exposure occurs during a limited time Interval I.e., for an Interval that
does not constitute a significant portion of the Hfespan. This type of
exposure estimate has not been extensively used, or rigorously defined as
previous risk assessment efforts have focused primarily on lifetime exposure
scenarios. Animal data used for subchronic estimates generally reflect
exposure durations of 30-90 days. The general methodology for estimating
subchronic RfDs 1s the same as traditionally employed for chronic estimates,
except that subchronic data are utilized when available.
In the case of suspected carcinogens, RfDs are not estimated. Instead,
a carcinogenic potency factor, or q-|* (U.S. EPA, 1980b), Is provided.
These potency estimates are derived for both oral and Inhalation exposures
where possible. In addition, unit risk estimates for air and drinking water
are presented based on Inhalation and oral data, respectively.
Reportable quantities (RQs) based on both chronic toxlclty and carclno-
genldty are derived. The RQ 1s used to determine the quantity of a hazard-
ous substance for which notification 1s required In the event of a release
as specified under the Comprehensive Environmental Response, Compensation
and Liability Act (CERCLA). These two RQs (chronic toxlclty and cardno-
genlclty) represent two of six scores developed (the remaining four reflect
1gn1tab1lHy, reactivity, aquatic toxlclty, and acute mammalian toxlclty).
Chemical-specific RQs reflect the lowest of these six primary criteria. The
methodology for chronic toxlclty and cancer based RQs are defined In U.S.
EPA, 1984 and 1986, respectively.
111
-------
EXECUTIVE SUMMARY
Bromoform (CAS number 75-25-2) Is a colorless, heavy liquid at room
temperature with an odor and taste similar to chloroform (Hawley, 1981). It
Is sparingly soluble In water but soluble In ethanol, ethyl ether, chloro-
form, benzene, solvent naphtha and fixed and volatile oils (Hawley, 1981;
Stenger, 1978). It 1s a nonflammable liquid (Hawley, 1981). Bromoform Is
produced commercially from chloroform by replacement of chloride by reaction
with anhydrous aluminum bromide, treatment with bromine and aluminum, or
reaction with hydrogen bromide In the presence of an aluminum hallde
catalyst {Stenger, 1978). Geollqulds, Inc., a division of National
Biochemical Co., Chicago, IL, Is currently the only domestic manufacturer
of this compound (SRI, 1987). Bromoform 1s used as an Intermediate 1n'
organic synthesis; In Pharmaceuticals as a sedative and antHussWe; In
gauge fluids; as a solvent for waxes, greases and oils; as an Ingredient In
fire-resistant chemicals; and as a heavy-dense liquid 1n solid separations
based on differences 1n specific gravity, such as geological assaying
(Stenger, 1978; Hawley, 1981; Verschueren, 1983).
Based on a vapor pressure of 5.6 mm Hg at 25°C (Verschueren, 1983),
bromoform 1s expected to exist primarily 1n the vapor phase 1n the atmo-
sphere. Direct photolysis In the troposphere 1s not expected to be signifi-
cant because trlhalomethanes as a class do not absorb UV radiation at >290
nm (Perwak et al., 1980). Reaction of bromoform with photochemlcally
generated hydroxyl radicals [half-life of 325 days (Atkinson, 1987)] may be
one removal mechanism. The likely product of photooxldatlon of bromoform Is
COBr™, which may be removed by rain that will hydrolyze It to CCL and
HBr (Raddlng et al., 1977). Therefore, bromoform may have a long residence
1v
-------
time 1n air and may undergo long distance transport. Based on Us residence
time, <15C of tropospheMc bromoform may be transferred to the stratosphere.
In water, bromoform will not be expected to adsorb significantly to sediment
and suspended solids, or to hydrolyze. Blodegradatlon of bromoform In water
under aerobic and anaerobic conditions may be a significant removal process
based on the results of laboratory screening tests. Volatilization from
water Is expected to be a significant loss process. Bromoform Is expected
to be highly mobile In soil; therefore, 1t may leach Into groundwater. The
relatively high vapor pressure of bromoform [5.6 mm Hg {Verschueren, 1983)]
suggests that volatilization from dry soil surfaces 1s likely to be signifi-
cant. Blodegradatlon of bromoform In soil and groundwater may be a
significant removal process, based on the results of soil percolation
studies (Bouwer et al., 1984) and aerobic and anaerobic laboratory screening
tests In water. Hydrolysis 1s not expected to be an Important removal
process 1n soil.
Exposure of the general population to bromoform Is most likely to occur
from Ingestlon of contaminated drinking water and Inhalation of contaminated
ambient air. Minor dermal exposure may occur 1n swimming pools, especially
beachfront pools that use salt water. Occupational exposure standards warn
of possible significant skin absorption for tMbromomethane under Industrial
exposure conditions (OSHA, 1976), but no evidence In the available litera-
ture cited In Appendix A Indicates that dermal exposure contributes signifi-
cantly to the total dose of trlbromomethane for the general public (U.S.
EPA, 1980a). Bromoform has been found In samples of drinking water, ground-
water, surface water, effluent from publicly-owned treatment works, sedi-
ment, marine algae and ambient air. The U.S. EPA STORET Data Base (U.S.
EPA, 1988) Indicates that bromoform was found In samples of sediment (44
-------
total samples) at a concentration range of 0.10-0.025 ppm (wet weight) and
an average concentration of 0.014 ppm. Bromoform has been found In several
species of algae, but no Information regarding Its presence In foods was
found In the available literature cited In Appendix A.
The acute toxldty of bromoform to freshwater fish was determined for
blueglll sunflsh and common carp. The 96-hour LC s for sunflsh exposed
to bromoform were 29.3 ppm {U.S. EPA, 1978) and 29 mg/i (Buccafusco et
a!., 1981). The NOEC reported by U.S. EPA (1978) was 13 ppm. HattUe et
al. (1981) and Trabalka et al. (1979) reported that the LC,n for common
DU
carp eggs exposed to bromoform was 52 mg/J.. The acute toxldty of bromo-
form to saltwater fish was determined for menhaden and sheepshead minnow.
The 96-hour IC™ for menhaden exposed to bromoform was 12 mg/8, (Gibson
et al., 1979a,b, 1981). The 96-hour LC5Q for sheepshead minnow exposed to
bromoform was 18 ppm In a static test (HeHmuller et al., 1981) and 7.1
rng/a In a flowthrough test (Ward et al., 1981). Heltmuller et al. (1981)
reported a NOEC of 2.9 ppm, while U.S. EPA (1978) reported a NOEC for
sheepshead minnow exposed to bromoform of 4.83 ppm and a MATC of >4.83 to
<8.5 ppm.
The acute toxldty of bromoform to molluscs was reported by Stewart et
al. (1979) and Gibson et al. (1979a,b, 1981). Survival among larvae of the
American oyster fell from >90 to -42% at bromoform concentrations from 0-10
mg/a. Inadequate levels of mortality among adult clams and oysters
prevented calculation of LC,-ns for these species.
U.S. EPA (1978) and LeBlanc (1980) reported 48-hour
for Daphnla
magna of 46.5 ppm, with a NOEC of <7.8 ppm. The 96-hour LC5Q for a
related species, Daphnla pulex. was 44 mg/i (Trabalka and Burch, 1978).
Richie et al. (1984) reported a 24-hour LC5Q of 75 ppm for larval
mosquitoes exposed to bromoform.
v1
-------
The 96-hour LC5Q for the saltwater crustacean, Mysldopsls bahla. was
24.4 ppm, while the NOEC was reported as 8.67 ppm (U.S. EPA, 1978). Gibson
et al. (1979a,b, 1981) reported a 96-hour LC5Q for shrimp of 26 mg/a.
Kerster and Schaeffer (1983) reported that bromoform was not teratogenlc to
brine shrimp nauplU at concentrations of 0.25-25 ppm.
Hard et al. (1981) reported that bromoform at concentrations of <15
mg/a had no effect on hatching success or growth of surviving sheepshead
minnow juveniles, while concentrations >8.5 mg/a significantly Increased
mortality among juveniles, producing an estimated MATC of >4.8 to <8.5.
Anderson et al. (1979), Gibson et al. (1979a,b,c. 1981) and Scott et al.
(1980, 1982, 1983) reported that bromoform was bloaccumulated 3- to 50-fold
by clams, oysters, shrimp and fish, but that depuration was very rapid (<2-4
days). A BCF value calculated from the log KQW for bromoform also'
Indicates that bromoform does not bloaccumulate significantly.
U.S. EPA (1978) reported 96-hour EC5Qs for cultures of the freshwater
green alga, Selanastrurn caprlcornutum. exposed to bromoform of 112 and 116
ppm, with a NOEC of 28.9 ppm. U.S. EPA (1978) also reported 96-hour EC5Qs
for cultures of the saltwater alga, Skeletonema costatum. exposed to bromo-
form of 12.3 and 11.5 ppm, with a NOEC of 1.73 ppm.
Bromoform Is absorbed through the respiratory tract, skin and gastro-
intestinal tract (Von Oettlngen, 1955), apparently quite readily from the
respiratory and gastrointestinal tracts. Once absorbed, bromoform and Us
metabolites are distributed rapidly, with highest levels located In adipose
tissue and blood (Parra et al., 1986). Substantial levels are also found 1n
several other organs Including the brain. Elimination occurs rapidly from
all tissues Including fat (Parra et al., 1986). Metabolism of bromoform
occurs predominantly In the liver by a cytochrome P450 oxldase system to CO
-------
and C02 (Ahmed et al., 1977, 1980; Stevens and Anders, 1979). Dlbromo-
carbonyl Is a likely toxic Intermediate 1n this pathway (NTP, 1988). Mice
appear to metabolize bromoform by this pathway more completely than do rats
(M1nk et al., 1986). Bromoform metabolism depletes liver GSH (Pohl et al.,
1980b) because this system 1s stimulated by sulfhydral compounds (e.g., GSH)
(Stevens and Anders, 1979; Ahmed et al., 1980). Bromoform also appears to
be metabolized through a reductive pathway that produces free radical Inter-
mediates. Excretion of bromoform and Its metabolites occurs to a small
extent from the urine and to a much larger extent through the lungs In mice,
rats (M1nk et al., 1986) and rabbits (Lucas, 1928).
The liver, kidneys and central nervous system appear to be Important
target organs for bromoform toxldty. Both Inhalation (Oykan, 1962, 1964)
and oral (NTP, 1988; Chu et al., 1982a,b; Borzelleca, 1983) administration'
result In aberrations In morphology or function of these organs. Hepato-
cellular vacuollzatlon was found In both male mice (>200 mg/kg/day) and male
rats (>50 mg/kg/day) 1n a subchronlc study (13 weeks, 5 days/week) and In
female mice (>100 mg/kg/day) In a chronic study (103 weeks, 5 days/week)
sponsored by NTP (1988). Compound-related mortality was observed In male
rats (200 mg/kg/day) In the chronic study. Also, narcosis (Sax, 1984) and
lethargy (Bowman et al., 1978; Chu et al., 1980; NTP, 1988) were observed 1n
animals receiving bromoform by Inhalation and oral routes, respectively.
Altered RES function was observed In male and female mice receiving bromo-
form at a level of 125 mg/kg/day for 90 days by gavage (Hunson et al., 1977,
1978). Operant behavior was Impaired after administration of bromoform to
mice at levels of 100 and 400 mg/kg/day for 60 days (Balster and Borzelleca,
1982).
NTP (1988) concluded that there was "some evidence of carclnogenlclty of
bromoform for male F344/N rats and clear evidence...for female F344/N rats."
-------
Female rats at 200 mg/kg/day displayed a higher Incidence of neoplastlc
lesions of the large Intestine compared with male rats and untreated
controls {NTP, 1988). This may be due tn part to the fact that male rats
had reduced survival rates compared with females at equal doses (NTP, 1988).
In another study (Thelss et al., 1977} bromoform produced an Increase In the
number of pulmonary adenomas per mouse In strain A mice following Intraperl-
toneal administration. Bromoform tested positive for mutagenlclty In both
iD. yjyg and j£ vitro assays (NTP, 1988). Bromoform did not produce terato-
genlc effects or maternal toxldty, but did produce fetotoxlc effects In
rats treated at 100, but not at 50 mg/kg/day (Ruddlck et al., 1983).
A subchronlc oral RfD of 0.2 mg/kg/day was derived by applying an
uncertainty factor of 100 to the NOEL of 17.9 mg/kg/day In rats In the NTP
(1988) 13-week gavage study. Hepatocellular vacuollzatlon occurred at*
higher doses. The subchronlc oral RfD was used as the basis for the chronic
oral RfD of 0.02 mg/kg/day after an additional subchron1c-to-chron1c
uncertainty factor of 10. A q * of 7.9xlO~3 (mg/kg/day)""1 based on an
Internal dose was derived from the Incidence of tumors In the large
Intestine of female rats treated by gavage for 2 years (NTP, 1988). This
estimate of cancer potency Is considered valid for oral exposure. Bromoform
1s assigned to U.S. EPA we1ght-of-ev1dence group B2 - Probable Human Car-
cinogen.
1x
-------
TABLE OF CONTENTS
1. INTRODUCTION 1
1.1. STRUCTURE AND CAS NUMBER 1
1.2. PHYSICAL AND CHEMICAL PROPERTIES 1
1.3. PRODUCTION DATA 2
1.4. USE DATA 3
1.5. SUMMARY 3
2. ENVIRONMENTAL FATE AND TRANSPORT 4
2.1. AIR 4
2.1.1. Chemical Reactions 4
2.1.2. Photolysis 4
2.2. WATER 5
2.2.1. Hydrolysis 5
2.2.2. Oxidation 5
2.2.3. Adsorption 5
2.2.4. Volatilization 5
2.2.5. Blodegradatlon 5
2.3. SOIL 7
2.3.1. Hydrolysis 7
2.3.2. Leaching 7
2.3.3. Volatilization 7
2.3.4. Blodegradatlon 7
2.4. SUMMARY 8
3. EXPOSURE 10
3.1. WATER 10
3.2. FOOD 14
3.3. INHALATION 15
3.4. DERMAL 15
3.5. SUMMARY 16
4. ENVIRONMENTAL TOXICOLOGY 17
4.1. AQUATIC TOXICOLOGY 17
4.1.1. Acute Toxic Effects on Fauna 17
4.1.2. Chronic Effects on Fauna 21
4.1.3. Effects on Flora 23
4.1.4. Effects on Bacteria 24
-------
TABLE OF CONTENTS (cent.)
Page
4.2. TERRESTRIAL TOXICOLOGY 24
4.2.1. Effects on Fauna 24
4.2.2. Effects on Flora 25
4.3. FIELD STUDIES 25
4.4. SUMMARY 25
5. PHARMACOKINETCS 27
5.1. ABSORPTION 27
5.2. DISTRIBUTION 28
5.3. METABOLISM 29
5.4. EXCRETION 33
5.5. SUMMARY 33
6. EFFECTS 35
6.1. SYSTEMIC TOXICITY 35
6.1.1. Inhalation Exposure 35
6.1.2. Oral Exposure 35
6.1.3. Other Relevant Information 40
6.2. CARCINOGENICITY 44
6.2.1. Inhalation 44
6.2.2. Oral 44
6.2.3. Other Relevant Information 47
6.3. MUTAGENICITY 48
6.4. TERATOGENICITY 48
6.5. OTHER REPRODUCTIVE EFFECTS 51
6.6. SUMMARY 51
J. EXISTING GUIDELINES AND STANDARDS 53
7.1. HUMAN 53
7.2. AQUATIC 53
8. RISK ASSESSMENT 54
8.1. CARCINOGENICITY 54
8.1.1. Inhalation 54
8.1.2. Oral 54
8.1.3. Other Routes 54
8.1.4. Height of Evidence 54
8.1.5. Quantitative Risk Estimates 55
x1
-------
TABLE OF CONTENTS (cont.)
Page
8.2. SYSTEMIC TOXICITY 57
8.2.1. Inhalation Exposure 57
8.2.2. Oral Exposure 58
8.3. AQUATIC 61
9. REPORTABLE QUANTITIES 65
9.1. BASED ON SYSTEMIC TOXICITY 65
9.2. BASED ON CARCINOGENICITY 71
10. REFERENCES 73
APPENDIX A: LITERATURE SEARCHED 97
APPENDIX B: CANCER DATA SHEET FOR DERIVATION OF q^ 100
APPENDIX C: SUMMARY TABLE FOR BROMOFORM 101
-------
LIST OF TABLES
No. Title Page
3-1 Frequency of Occurrence and Concentration of Bromoform In
U.S. EPA MOMS Survey of 113 Water Supplies 11
3-2 Summary of Frequency of Occurrence and Concentration
Data for Bromoform 1n Finished Water from Drinking Hater
Treatment Plants 12
6-1 1059 and LC5Q Values for Bromoform 41
6-2 . Incidence of Tumors of the Large Intestine In F344/N Rats
Treated by Gavage with Bromoform (>9554 pure) 1n Corn Oil
for 103 Weeks 45
6-3 Incidence of Tumors of the Respiratory Tract In B6C3F1 Mice
Treated by Gavage with Bromoform (>95X pure) In Corn 011 for
103 Weeks 46
6-4 Mutagenlclty Testing of Bromoform 49
9-1 Toxlclty Summary for Bromoform 66
9-2 Oral Composite Scores for Bromoform 68
9-3 Bromoform: Minimum Effective Dose (MED) and Reportable
Quantity (RQ) 70
9-4 Derivation of Potency Factor (F) for Bromoform 72
-------
LIST OF FIGURES
Title
Proposed Metabolic Pathway for Bromoform.
Organization chart for listing FHAVs required to derive
numerical water quality criteria by the method of EPA/OWRS
(1986) for the protection of freshwater aquatic life from
exposure to bromoform
62
8-2
Organization chart for listing FMAVs required to derive
numerical water quality criteria by the method of EPA/OURS
(1986) for the protection of saltwater aquatic life from
exposure to bromoform
63
xlv
-------
LIST OF ABBREVIATIONS
ADI Acceptable dally Intake
ALA 6-Am1nolevul1n1c add
BCF Bloconcentratlon factor
BUN Blood urea nitrogen
CO Carbon monoxide
COX2 Carbonyl halldes
CS Composite score
DNA Deoxyrlbonuclek acid
ECso Concentration effective to 50% of recipients
(and all other subscripted concentration levels)
FMAV Family mean acute values
GOT Glutamlc oxaloacetlc transamlnase
GSH Reduced glutathlone
Koc Soil sorptlon coefficient standardized
with respect to organic carbon
Kow Octanol/water partition coefficient
LC$Q Concentration lethal to 50% of recipients
(and all other subscripted dose levels)
LDH Lactate dehydrogenase
LOso Dose lethal to 50% of recipients
LD|_o Lowest dose lethal to recipients
LOAEL Lowest-observed-adverse-effect level
LOEL Lowest-observed-effect level
MATC Maximum allowable toxicant concentration
MED Minimum effective dose
MTO Maximum tolerated dose
NADPH N1cot1nam1de adenlne dlnucleotlde phosphate
(reduced form)
xv
-------
LIST OF ABBREVIATIONS (cont.)
NOAEL
NOEC
NOEL
OZT
PAH
PEL
ppm
ppb
ppt
RES
RfD
RNA
RQ
RVd
RVe
SCE
SDH
SGOT
SGPT
TLV
UV
v/v
w/v
No-observed-adverse-effect level
No-observed-effect concentration
No-observed-effect level
2-Oxoth1azol1d1ne-4-carboxyl1c add
p-Am1noh1ppur1c add
Permissible exposure level
Parts per million
Parts per billion
Parts per trillion
Retlculoendothellal system
Reference dose
Rlbonuclelc add
Reportable quantity
Dose-rating value
Effect-rating value
Slster-chromatld exchange
Sucdnlc dehydrogenase
Serum glutamlc oxaloacetlc transamlnase
Serum glutamlc pyruvlc transamlnase
Threshold limit value
Ultraviolet
Volume per volume
Height per volume
i
xv1
-------
1. INTRODUCTION
1.1. STRUCTURE AND CAS NUMBER
Bromoform 1s the common name for tMbromomethane (Stenger, 1978). The
structure, molecular weight, empirical formula and CAS Registry number for
this compound are as follows:
Br
I
H-C-Br
I
Br
Molecular weight: 252.77
Empirical formula: CHBr~
o
CAS Registry number: 75-25-2
1.2. PHYSICAL AND CHEMICAL PROPERTIES
Bromoform 1s a colorless, heavy liquid at room temperature with an odor
and taste similar to chloroform (Hawley, 1981). It 1s soluble In ethanol,
ethyl ether, chloroform, benzene, solvent naphtha and fixed and volatile
oils {Hawley, 1981; Stenger, 1978). Bromoform 1s nonflammable (Hawley,
1981). Under certain conditions, bromoform can undergo nucleophlUc substi-
tution reactions; however, the compound Is reasonably stable toward chemical
reactions under most environmental conditions (Chapter 2).
Selected physical properties are as follows:
Boiling point: 149.5°C Stenger, 1978
Melting point: 7.7°C Stenger, 1978
Vapor pressure (25°C): 5.6 mm Hg Verschueren, 1983
Log Kow: - 2.37 U.S. EPA, 1987a
(estimated)
Water solubility (25°C): 3100 mg/a. Horvath, 1982
Specific gravity (20°C): 2.887 Hawley, 1981
0125d -1- 01/17/89
-------
Refractive index, n
Odor threshold:
air
water
19
1.5980
1.3 ppm (v/v)
0.51 ppm (w/v)
Stenger, 1978
Amoore and
Hautala, 1983
Amoore and
Hautala. 1983
1.3. PRODUCTION DATA
In 1977, Dow Chemical Company U.S.A. manufactured between 0.1 and 1.0
million pounds of bromoform, 01 In Corp. manufactured between 10 and 100
thousand pounds, and Freeman Industries, Inc., manufactured between 1 and 10
thousand pounds (U.S. EPA, 1977). Rhone-Poulenc, Inc., was reported to be
an Importer of bromoform In 1977 (U.S. EPA, 1977). SRI (1987) lists
Geollqulds, Inc., Division of National Biochemical Co., Chicago, IL, as the
only current producer of bromoform.
Bromoform 1s produced commercially from chloroform by replacement of
chloride by reaction with anhydrous aluminum bromide, treatment with bromine
and aluminum, or reaction with hydrogen bromide In the presence of an
aluminum hallde catalyst (Stenger, 1978). After the chlorine Is replaced
with bromine, the mixture 1s washed with cold water to remove Inorganic
materials and the product 1s distilled (Stenger, 1978). Bromoform also can
be produced by heating ethanol or acetone with bromine and alkali hydroxide
(Hawley, 1981) or with sodium hypochlorlte and. a bromide (Stenger, 1978).
Bromoform 1s usually sold with 3-4% ethanol added as a stabilizer (Stenger,
1978).
Bromoform 1s produced Inadvertently during chloMnatlon of potable water
and wastewaters as a result of reaction of chlorine with humlc substances
and naturally-occurring bromide Ions present In water {Stenger, 1978).
Bromoform appears to be a natural product In the marine environment; the
compound was quantified 1n several species of algae (Section 3.2.) (Gschwend
et al., 1985; Callahan et al., 1979).
0125d
-2-
11/09/88
-------
1.4. USE DATA
Bromoform 1s used as an Intermediate In organic synthesis; In pharma-
ceutlcals as a sedative and antHusslve; In gauge fluids; as a solvent for
waxes, greases and oils; as an Ingredient In fire-resistant chemicals; and
as a heavy-dense liquid In solid separations based on differences In
specific gravity, such as geological assaying {Stenger, 1978; Hawley, 1981;
Verschueren, 1983).
1.5. SUMMARY
Bromoform (CAS number 75-25-2) Is a colorless, heavy liquid at room
temperature with an odor and taste similar to chloroform (Hawley, 1981). It
1s sparingly soluble In water but soluble In ethanol, ethyl ether, chloro-
form, benzene, solvent naphtha and fixed and volatile oils (Hawley, 1981;
Stenger, 1978). It Is a nonflammable liquid (Hawley, 1981). Bromoform 1s
produced commercially from chloroform by replacement of chloride by reaction
with anhydrous aluminum bromide, treatment with bromine and aluminum, or
reaction with hydrogen bromide In the presence of an aluminum hallde
catalyst (Stenger, 1978). Geollqulds, Inc., a division of National
Biochemical Co., Chicago, IL, Is currently the only domestic manufacturer
of this compound (SRI, 1987). Bromoform 1s used as an Intermediate In
organic synthesis; 1n Pharmaceuticals as a sedative and antltusslve; In
gauge fluids; as a solvent for waxes, greases and oils; as an Ingredient 1n
fire-resistant chemicals; and as a heavy-dense liquid In solid separations
based on differences In specific gravity, such as geological assaying
(Stenger, 1978; Hawley, 1981; Verschueren, 1983).
0125d -3- 11/09/88
-------
2. ENVIRONMENTAL FATE AND TRANSPORT
2.1. AIR
Pertinent data regarding the environmental fate and transport of
bromoform In air are limited. Whenever possible, Information concerning the
environmental fate and transport of this compound was derived from physical
property data or molecular structure. Based on a vapor pressure of 5.6 mm
Hg at 25°C (Verschueren, 1983) and the estimation of Elsenrelch et al.
(1981), bromoform Is expected to exist primarily In the vapor phase In the
atmosphere.
2.1.1. Chemical Reactions. Using the method of Atkinson (1987), the rate
constant for reaction of bromoform vapor with photochemlcally produced
hydroxyl radicals 1n the atmosphere has been estimated to be 4.94xlO~i4
cmVmolecule-sec at 25°C. Based on this value and assuming an average'
ambient H0« concentration of 5.0x10' molecules/cm3, the half-life for
this reaction has been estimated to be 325 days. Although the reaction of
bromoform with photochemlcally produced hydroxyl radicals appears to be
slow, the reaction will be a significant removal process 1f there are no
other significant competing removal processes. The likely product of photo-
oxidation of bromoform Is COBr-, which may be removed by rain that will
hydrolyze 1t to C02 and HBr (Raddlng et al., 1977).
2.1.2. Photolysis. No specific Information regarding the rate of
photolysis of bromoform 1n the atmosphere was found In the available
literature. Direct photolysis 1n the troposphere 1s not expected to be
significant because trlhalomethanes as a class do not absorb UV radiation at
>290 nm (Perwak et al., 1980).
0125d
-4-
09/27/88
-------
2.2. HATER
2.2.1. Hydrolysis. The reported rate constant for the hydrolysis of
bromoform 1s 3. 2X1011 sec"1 at 25°C and pH 7 (Mabey and Hill, 1978).
This corresponds to a half-life of 686 years for hydrolysis of bromoform.
From this, 1t can be concluded that hydrolysis of bromoform Is not Important
1n the transformation of this compound 1n the aqueous environment.
2.2.2. Oxidation. No specific Information regarding the oxidation of
bromoform under aquatic conditions was found In the available literature.
2.2.3. Adsorption. A KQC of 282 was reported for an unspecified
aquifer material (Abdul et al., 1987). A K of 100 was estimated using a
measured water solubility of 3100 mg/a (Horvath, 1982) and the following
linear regression equation (Lyman, 1982):
log Koc = -0.557 log S+4.277 (2-1)
(S 1n
These K values suggest that bromoform would not sorb significantly to
sediment and suspended solids.
2.2.4. Volatilization. The volatilization half-lives for bromoform at
25°C In unstirred mineral water solutions at depths of 6.5 cm and 14.5 cm
are 23.9 and 65.4 minutes, respectively (Francois et al., 1979). Using a
measured Henry's Law constant of 6.6xlO~4 atm mVmol (Mine and
Mookerjee, 1975) and the method of Thomas (1982), a half-life of 6.7 hours
was estimated for volatilization of bromoform from a river 1 m deep flowing
1 m/sec with a wind velocity of 3 m/sec. Therefore, volatilization 1s
expected to be an Important loss process.
2.2.5. B1odegradat1on. Pertinent data regarding the blodegradatlon of
bromoform In natural waters were not located In the available literature
cited 1n Appendix A.
0125d -5- 09/27/88
-------
Bromoform at 5 ppm was inoculated with settled domestic waste-water seed
for 7 days, followed by 3 weekly subcultures at 25°C using a static culture
flask-screening procedure (Tabak et al., 1981). Percent blodegradatlon 1n
the original culture, and the first, second and third subcultures were 11,
22, 40 and 48, respectively, Indicating that significant degradation might
occur with adapted microorganisms and that adaptation was a slow process
{Tabak et al., 1981).
Bromoform at an Initial concentration of 26 ppb was >99% removed by
treatment 1n a methanogenlc (anaerobic conditions) blofUm column after a
2-day detention time In the presence of nitrate as an electron acceptor
(Bouwer and McCarty, 1984). Bromoform was not tested 1n the aerobic blofllm
column tests because H was not blodegraded 1n aerobic batch cultures
{Bouwer and McCarty, 1984). Under static anaerobic batch conditions In the'
presence of nitrate, bromoform at an average concentration of 66 ppb was 11,
44, 47 and 97% degraded after 2, 3, 4 and 6 weeks, respectively {Bouwer and
McCarty, 1983).
The above anaerobic degradation data are not consistent with field data
obtained from a groundwater recharge project In Palo Alto, CA, In which
reclaimed municipal wastewater was Injected directly (RUtmann et al.,
1980). The bromoform level from the Injection well to the observation well
(7.6 m between wells) was only slightly attenuated compared with that of
tracer chloride Ion. Apparently, the bromoform passed through the
biologically active zone without being degraded (RUtmann et al., 1980).
More recent data from the continuation of these studies, however, suggest
presumptive evidence of the degradation of bromoform In recharged ground-
water under anaerobic conditions (Roberts et al., 1982). The presence of an
electron acceptor 1n the reclaimed wastewater, such as nitrate, might be
necessary for blodegradatlon to occur.
Q125d
-6-
09/27/88
-------
The relative efficiency of removal of toxic pollutants, Including bromo-
form, from spiked raw wastewater by several wastewater treatment processes
was studied by Hannah et al. (1986). The percent removal of bromoform
reported with a conventional activated sludge system (residence time of 7.5
hours at design flow), a facultative lagoon system (hydraulic detention time
of 25.6 days) and an aerated lagoon system (hydraulic detention time of 6.4
days) was 65, 84 and 80%, respectively (Hannah et al., 1986).
2.3. SOIL
2.3.1. Hydrolysis. Based on available Information on the hydrolysis in
water, hydrolysis of bromoform Is not expected to be significant In the
transformation of this compound In soil (see Section 2.2.1.}.
2.3.2. Leaching. A K of 181 was calculated from a Freundllch K value
of 1.54 and a organic carbon content of 0.85% reported for a Keweenaw sandy
loam soil (Hutzler et al., 1986). A K of 100 was estimated using a
. QC
measured water solubility of 3100 mg/i (Horvath, 1982), and the linear
regression equation of Lyman (1982) (see Equation 2-1). These K values
suggest that bromoform would be moderately to highly mobile 1n soil (Swann
et al., 1983) and therefore would be expected to leach Into groundwater.
2.3.3. Volatilization. The relatively high vapor pressure of bromoform
[5.6 mm Hg (Verschueren, 1983)] suggests that volatilization from dry soil
surfaces 1s probably significant. Evaporation from moist soils may also be
significant, since bromoform does not have a strong tendency to adsorb to
soil and apparently evaporates rapidly from water solutions (see Sections
2.3.4. and 2.2.5.).
2.3.4. Blodegradatlon. A study of the movement of trace organic pollut-
ants, Including bromoform, during rapid Infiltration of secondary wastewater
for groundwater recharge Indicated that the likely cause of the decrease of
bromoform during soil percolation was blodegradatlon (Bouwer et al., 1984).
0125d -7- 09/27/88
-------
The renovated wastewater studied contained nitrate, which appears to be
necessary as an electron acceptor In the blodegradatlon process. The
degradation of the bromoform may have actually occurred In the area of the
groundwater and aquifer material, which was mainly anaerobic (Bouwer et al.,
1984).
2.4. SUMMARY
Based on a vapor pressure of 5.6 mm Hg at 25°C {Verschueren, 1983),
bromoform 1s expected to exist primarily 1n the vapor phase In the atmo-
sphofe. Direct photolysis In the troposphere Is not expected to be signifi-
cant because trlhalomethanes as a class do not absorb UV radiation at >290
nm (Perwak et al., 1980). Reaction of bromoform with photochemlcally
generated hydroxyl radicals [half-life of 325 days (Atkinson, 1987)] may be
one removal mechanism. The likely product of photooxldatlon of bromoform Is
COBr?, which may be removed by rain that will hydrolyze 1t to C0p and
HBr (Raddlng et al., 1977). Therefore, bromoform may have a long residence
time In air and may undergo long distance transport. Based on Us residence
time, <1% of tropospherlc bromoform may be transferred to the stratosphere.
In water, bromoform will not be expected to adsorb significantly to sediment
and suspended solids, or to hydrolyze. Blodegradatlon of bromoform In water
under aerobic and anaerobic conditions may be a significant removal process
based on the results of laboratory screening tests. Volatilization from
water 1s expected to be a significant loss process. Bromoform Is expected
to be highly mobile In soil; therefore, it may leach Into groundwater. The
relatively high vapor pressure of bromoform [5.6 mm Hg {Verschueren, 1983)]
suggests that volatilization from dry soil surfaces Is likely to be signifi-
cant. Blodegradatlon of bromoform 1n soil and groundwater may be a signifi-
cant removal process, based on the results of soil percolation studies
0125d
01/17/89
-------
(Bouyer et al., 1984} and aerobic and anaerobic laboratory screening tests
In water. Hydrolysis 1s not expected to be an Important removal process 1n
soil.
0125d -9- 09/27/88
-------
3. EXPOSURE
*
3.1. WATER
In the U.S. EPA National Organlcs Reconnaissance Survey (NORS) of 80
cities, bromoform was found 1n the finished drinking waters of 26 samples
(Symons et al., 1975). The concentration of bromoform 1n these positive
samples ranged from 0.0008-0.092 ppm; 93.3% of all the cities tested had a
bromoform concentration of <0.005 ppm (Symons et al.f 1975). The authors
concluded that bromoform was formed as a result of chlorlnatlon and that Us
concentrations were related to the organic content of the water.
In Us Region V Organlcs Survey of 83 sites, the U.S. EPA (1980a)
reported that drinking water from 14% of the locations contained detectable
levels of bromoform, with a median concentration of 0.001 ppm and a maximum
concentration of 0.007 ppm.
The U.S. EPA National Organic Monitoring Survey (MOMS), conducted 1n
three phases during 1976 and 1977, sampled 113 water supplies representing
various sources and treatments (U.S. EPA, 1980a). Incidence and concentra-
tion data are summarized 1n Table 3-1.
Data from a Canadian national survey for halomethanes In drinking water
are In general agreement with data from the United States (U.S. EPA, 1980a).
Samples taken from 70 finished water distribution systems showed bromoform
at concentrations ranging from 0-0.2 ppb, with a median concentration of
0.01 ppb.
Data regarding the Incidence and concentration of bromoform In finished
drinking waters are summarized In Table 3-2.
Using the median values from Table 3-2, an average dally Intake can be
estimated. The values used represent -28% positive values out of 945 data
points from drinking water plants (Westrlck et al., 1984). The average and
0125d
-10-
11/10/88
-------
TABLE 3-1
Frequency of Occurrence and Concentration of Bromoform In U.S. EPA
NOMS Survey of 113 Water Supplies3
Number of Positive
Analyses per
Number of Analyses
Mean Concentration
ppb (Positive
Results Only)
Median Concentration
ppb (All Results)
Phase
Qb
Tb
I II III I II III I
3/lllc 6/118 19/106 21C 28 13 3-5d
38/116 30/105 NA 12 13 NA
II III
3d 0.2-0.6d
3d 0.3-0.6d
aSource: U.S. EPA, 1980a
^Quenched (Q) samples were preserved with sodium thlosulfate at sampling,
shipped at ambient temperature and stored at 20-25°C 3-6 weeks before
analyses. Terminal (T) samples were treated similarly to Q except there
was no sodium thlosulfate treatment.
cSamples were shipped Iced and were stored refrigerated 1-2 weeks before
analyses.
^Minimum quantifiable limits.
NA = Not applicable
0125d
-11-
11/10/88
-------
Cu
1
en
CB
£
VI
E
a.
E
I
L.
i
E
C
O
§
14-
i
VI
E
B
e
£
OS
o
u
B
O
'g
*8
cu
u
E
a>
u
0
o
u
E
1
^
e
i
5
u
B
cu
fe
cu
Qg
|f
B
II
B a.
* —
VI CU
E »
&. ^
e
*a.
12
I
e
0)
.
fa. VI
0) «•
i ** *
E
O ^"*
U >>
o —
3? o
^ CD
» f— CNJ CM
— GB CD
^ * on o%
a IB • •
E cu * n)
oi E cu o
o — e e
p- ^ o a
u. X O 0
O O V *V
2 31 i S
r I 1
Z X Z Z
10
^ Of Jl O
t. L.
fCU
1
z £ S.S S.%
^E ^E Pv C/j PI V7
1 1
VI VI
a a
e< D>
a a
« <
§ ° S 8
-
B
— S3" 5 w 5 Sr
"5 c £ e en c «n
K uC. o ~ cj C.
CM <•> « * »
CO <0 CO CO CO
CM s 5 2 ? 2 '2
g 5
r— ifl X
Wi «»
•"^^^ • uuuw
E E e e cu »4>'Z^'u'Z
S c, SS S 5 5«?I55i
7 x z e! z z IE z z z z
ex. o oee ac ae ae • . ^ ^
2 * o 2 »
T o i i T i
S S S m z ^ z z z z z
P^ C^ ^** uD ^f es«iM
few
u
o , ^ *• * *• c »^ oe oe ac oc oe oe
"fc'^l'~'c'~TI x x z z x z
"3 v» *5 ^
•^
£
^9 (3 ^3 C5 CT OO OS >9 *«O *^ ^D
"--- ^.JOCBJSJ^
-. -. «. «.
KM >m »m IB r» cu 01 01 a«- u <9 u <9 U O U Q. O. i-i33333
i
\
^
•
^
1
1
£
«
*rf
|A W»
«• e
•s. *
ex <*
in c
L. r—
o» a.
«rf
i *,
B L. 01
c. vi vi S 4>
DI BE a -M
O O C OP
E vi vi ^
i. t> t> at > e
c* vi O O V" **
cu cu e o ^ H
5— « .nod
vi o a ** ax
^ ^ u
Bi'C V A « v> ••
e cu i— cv ^
_ «> Ol 0>OI r- CU
Z lu i- i_ i- 2 a
' "" S S B » k.
•a >> -or—
Jigii^-s
vi 5 £ £ t. oz
»• ^ f ++ i
6 B VI VI B }C 11
:: ££i> ^iH
01?5d
-12-
11/09/88
-------
range of the median values are 3.8 and 2.1-5.1 ppb, respectively (Westrlck
et al., 1984). Using the average median value of 3.8 ppb, an estimated
average dally Intake of 7.6 yg Is obtained, assuming an average consump-
tion of 2 l of drinking water/day.
A survey of groundwaters In New Jersey from 1977-1979 found bromoform 1n
22% of 1072 samples tested (Page, 1981); concentrations ranged from 0.1 ppb
(minimum reportable concentration) to 34.7 ppb {Burmaster, 1982). Bromoform
was detected In groundwater from Delaware at a concentration of 20 ppb (Rao
et al., 1985), and 1n groundwater from the Netherlands at a maximum concen-
tration of 4 ppb (Zoeteman et al., 1981).
Bromoform was detected in 3% of 204 water samples collected near Indus-
trial sites 1n the United States (Helz, 1980). A survey of surface waters
1n New Jersey from 1977-1979 found bromoform in 32.6% of 604 sites, with a'
maximum reported concentration of 3.7 ppb {Page, 1981). Bromoform concen-
trations 1n the Iowa River from October 1977 through October 1978 ranged
from <0.5 ppb {detection limit) to 6 ppb, with an average concentration of
1.7 ppb (Veenstra and Schnoor, 1980). Bromoform was detected 1n 35.3% of
water samples from 17 stations In the lower Niagara River 1n 1981 at concen-
trations ranging from trace to 6 ppt (Kaiser et al., 1983). Also, bromoform
was detected in 12.2% of water samples from 82 stations 1n Lake Ontario In
1981 at concentrations ranging from trace to 7 ppt (Kaiser et al., 1983),
and In 7% of 30 water samples collected In the Delaware River basin In
February, 1976 (DeWalle and Chlan, 1978). A North Sea survey that Included
108 samples of water from 9 locations collected on 6 cruises during 1983 and
1984 found bromoform at concentrations ranging from <5 ppt (detection limit)
to 264 ppt, with average and median concentrations of 23 and 7 ppt, respec-
tively (van de Meent et al., 1986). Water samples collected 1n 1985 from
0125d -13- 11/09/88
-------
the North and South Atlantic Ocean contained bromoform at concentrations of
0.8 and >6 ppt, respectively (Class et al., 1986).
The U.S. EPA STORE! Data Base (U.S. EPA, 1988) Indicates that bromoform
was found 1n samples of sediment (44 total samples) at a concentration range
of 0.10-0.025 ppm {wet weight) and an average concentration of 0.014 ppm.
Bromoform was detected In the secondary effluent from one of nine
publicly owned treatment works 1n Illinois In 1980 (Ellis et al., 1982).
Rainwater from three of four storms In a semi-rural area of Portland,
OR, during March-April 1982 contained bromoform at concentrations ranging
from 0.26-0.50 ppt, with an average concentration of 0.3 ppt (Pankow et al.,
1984). Rainwater from five storms 1n a residential area of Southeast
Portland, OR, during October-December 1982 contained bromoform at concentra-
tions ranging from 0.18-1.5 ppt, with an average concentration of 0.88 ppt'
(Pankow et al., 1984). Rainwater samples from Southern Germany collected In
1985 contained bromoform at a concentration of 5 ppt (Class et al., 1986).
3.2. FOOD
Pertinent data regarding exposure to bromoform fay Ingestlon of contami-
nated food were not located In the available literature cited 1n Appendix A.
Gschwend et al. (1985) reported that bromoform appears to be a natural
product In the marine environment, and that the compound was quantified In
several species of algae Including the brown algae, Ascophyllum nodosum
(150-12,500 ppb dry weight, 4500 ppb average), and Fucus veslculosls
(140-4700 ppb, 2200 ppb average); the green algae, Entormorpha Unza (not
detected-850 ppb) and Ulva lacta (1700-14,000 ppb); and the red algae,
Glgartlna crlspus (not detected-2100 ppb). Bromoform Is produced by a red
seaweed of the genus Asparagopsls at a concentration of IX of the total
plant composition (dry weight) (Callahan et al., 1979).
0125d
-14-
01/17/89
-------
3.3. INHALATION
Ambient air samples at four selected sites 1n the California South Coast
air basin were surveyed for the presence of halogenated hydrocarbons between
November 1982 and December 1983 (Shlklya et al., 1984). The sites were
located 1n downtown Los Angeles (DOLA) near three freeways, 15 km east of
DOLA downwind of urban areas and light Industry, 25 km south of DOLA
downwind of heavy Industry, and 75 km east of DOLA downwind of urban area.
Thirty-one percent of the samples detected bromoform above Its quantHatlon
limit (0.01 ppb). Peaks 1n the concentration of bromoform were observed at
the various sites In May and June, with the DOLA site registering the
highest composite mean (0.04 ppb) and highest monthly mean {0.31 ppb) In
•June 1983 (Shlklya et al.. 1984).
Bromoform was detected In the ambient air at the following U.S.
locations [location and year, number of samples/percent of samples positive,
range and mean (ng/m3)]: El Dorado, AR, 1976-1977, 46/76%, ND-2.7, 0.81;
Lake Charles, LA, 1978, 4/100%, 6.6-71, 50; Magnolia, AR, 1977, 28/89.3%,
ND-8.3, 1.5 (Brodzlnsky and Singh, 1982).
Bromoform was found in 100% of 34 samples of Arctic air from 8 sites
near Alaska, Greenland, Norway and the North Pole; the samples were col-
lected during March and April 1983 (Berg et al., 1984). The concentrations
of the compound ranged from 2-46 ppt, with an average of 15 ppt.
3.4. DERMAL
Occupational exposure standards warn of possible significant skin
absorption for bromoform under Industrial exposure conditions (OSHA, 1976);
however, no evidence 1n the available literature cited In Appendix A
Indicates that dermal exposure contributes significantly to the total dose
of trlbromomethane for the general public (U.S. EPA, 1980a).
0125d -15- 11/10/88
-------
Beech et al. (1980) monitored trlbromomethane levels 1n swimming pools
In the Miami area. Trlbromomethane concentrations In 101 city and
beachfront freshwater pools averaged <0.002 mg/8., which 1s consistent with
levels monitored In drinking waters; however, bromoform concentrations
monitored In 18 beachfront saline pools averaged 0.651 mg/l, an Increase
of >300-fold. The Increase was attributed to the bromide 1on concentrations
1n the salt water. Beech et al. (1980) suggested that the absorption of
trlhalomethanes through the skin In pools should be studied further.
3.5. SUMMARY
Exposure of the general population to bromoform 1s most likely to occur
from Ingestlon of contaminated drinking water and Inhalation of contaminated
ambient air. Minor dermal exposure may occur In swimming pools, especially
beachfront pools that use salt water. Occupational exposure standards warn
of possible significant skin absorption for trlbromomethane under Industrial
exposure conditions (OSHA, 1976), but no evidence In the available
literature cited 1n Appendix A Indicates that dermal exposure contributes
significantly to the total dose of trlbromomethane for the general public
(U.S. EPA, 1980a). Bromoform has been found 1n samples of drinking water,
groundwater, surface water, effluent from publicly-owned treatment works,
sediment, marine algae and ambient air. The U.S. EPA STORET Data Base (U.S.
EPA, 1988) Indicates that bromoform was found 1n samples of sediment (44
total samples) at a concentration range of 0.10-0.025 ppm (wet weight) and
an average concentration of 0.014 ppm. Bromoform has been found In several
species of algae, but no Information regarding Us presence 1n foods was
found 1n the available literature cited In Appendix A.
0125d
-16-
01/17/89
-------
4. ENVIRONMENTAL TOXICOLOGY
4.1. AQUATIC TOXICOLOGY
4.1.1. Acute Toxic Effects on Fauna. The 24-, 48-, 72- and 96-hour
LC50s (and 95% confidence limits) for blueglll sunflsh, Lepomls
macrochlrus. exposed to bromoform were 33.2 (27.4-42.2), 33.2 (27.4-42.2),
30.5 (25.0-37.9) and 29.3 ppm (24.0-36.2), respectively (U.S. EPA, 1978).
The 96-hour no effect concentration was reported as 13.0 ppm (U.S. EPA,
1978).
Gibson et al. (1979a,b, 1981) determined the acute toxldty of bromoform
to clams, Protothaca stamlnea and Hercenarla mercenarla. oysters,
Crassostrea vlrqlnlca. shrimp, Penaeus aztecus. and menhaden, Brevoortla
tyrannus. Specimens of P.. sjajnlnea were held 1n 30 a. glass aquaria with
~5 cm of coarse sand and flowing seawater for 4 days before the Initiation'
of testing. Bromoform was Introduced Into the exposure tanks by bubbling
bromoform-saturated air through the tanks. Bromoform-contamlnated air flows
were adjusted to maintain target concentrations. Salinity and temperature
were not measured, but seasonally range from 29-31 ppt and 7-13°C, respec-
tively, for the period of testing. Shrimp and menhaden held 1n circular
outdoor holding tanks with a continuous supply of sand and activated
charcoal-filtered seawater were fed Purina trout chow on a dally basis. M.
mercenarla and oysters were held In fiberglass water tables supplied with
unflltered seawater. Food other than that present In the seawater was not
provided. Clams and shrimp were tested separately, while oysters and
menhaden were exposed In a common chamber. The 96-hour LC5Qs (and 95%
confidence Intervals) for shrimp and menhaden were 26 (20-33) and 12 mg/s.
(9-15), respectively. Inadequate levels of mortality among molluscs exposed
to the highest concentrations of bromoform prevented calculation of LC5Qs
for these species, which the Investigators estimated would be >30-4Q mg/fc.
0125d -17- 11/09/88
-------
Buccafusco et al. (1981) exposed blueglll sunflsh, L_. macrochlrus. to
bromoform 1n well water at a test temperature of 21-23°C-under static condi-
tions. They reported nominal 24- and 96-hour LC.ns of 33 and 29 mg/fc,
respectively. Confidence Intervals (95%) were reported for the 96-hour
LC5Q only (24-36 mg/l).
Heltmuller et al. (1981) exposed sheepshead minnows, Cyprlnldon
varleqatus. to bromoform In filtered natural seawater In static tests for .96
hours. Test solutions were not aerated during the study, which was
conducted at a temperature of 25-31°C. These Investigators reported nominal
24- and 48-hour LC5Q values (and 95% confidence limits) of 19 ppm (16-23)
and 72- and 96-hour LC5 values (and 95% confidence limits) of 18 ppm
(15-21), respectively. The Investigators also reported a NOEC of 2.9 ppm.
U.S. EPA (1978) reported a NOEC for sheepshead minnow exposed to bromoform'
of 4.83 ppm and an MATC of >4.83 to <8.5 ppm.
Hard et al. (1981) also assessed the acute toxldty of bromoform to
sheepshead minnows, C_. yarleqatus. Juvenile fish were exposed to bromoform
diluted with natural seawater In an Intermittent-flow system delivering 1
a/cycle at a rate of 4-7 cycles/hour. Salinity of seawater during the
96-hour study was 28/mti, with a mean temperature of 30°C. The Investi-
gators reported a 96-hour 1C (and 95% confidence limits) of 7.1 mg/i
(4.6-11).
MattUe et al. (1981) and Trabalka et al. (1979) assessed the acute
toxldty of bromoform to common carp, Cyprlnus carplo. embryos In a static
renewal study. Recently fertilized eggs (100-300 per treatment) were
exposed to bromoform In 300 yl glass dishes at a test temperature of 26°C
until hatching was complete (within 3-5 days). Test solutions were renewed
45 minutes after eggs were first placed In test solutions and every 8 hours
0125d
-18-
09/27/88
-------
thereafter. The nominal LC5Q (and 95% confidence limits) for eggs exposed
to bromoform from the end of water hardening of the egg to hatching was 76
mg/a (74-79). The Investigators also calculated a weighted LCrn to take
bU
Into account degradation of bromoform between changes of toxicant solution.
The weighted LC5Q was calculated to be 52 mg/l, with 95% confidence
limits ranging from 50-54 mg/a.. The calculated half-life for bromoform
under the conditions of the study was 6.9 hours.
The 24- and 48-hour LC^.s (and 95% confidence limits) for the fresh-
water cladoceran, Daphnla magna. exposed to bromoform were 55.6 (43.9-67.6)
and 46.5 ppm (42.3-51.4), respectively (U.S. EPA, 1978). The 48-hour NOEC
was reported as <7.8 ppm (U.S. EPA, 1978).
The 24-, 48-, 72- and 96-hour LC5Qs (and 95% confidence limits) for
the saltwater crustacean, Mysldopsls bahla. exposed to bromoform were 76.3'
(48.6-134), 60.1 (37.6-100), 60.1 (37.6-100) and 24.4 ppm (16.9-32.6),
respectively (U.S. EPA, 1978). The 96-hour NOEC was reported as 8.67 ppm
(U.S. EPA, 1978).
Trabalka and Burch (1978) assessed the toxlclty of bromoform to the
cladoceran, Paphnla pulex. Tests were conducted at 20^1°C In 80 ml of
test solution with 2 daphnlds/repHcate and 10 replicates/concentration.
Daphnlds were fed trout chow twice weekly. The Investigators reported a
96-hour LCgg of 44 mg/4, for D. pulex exposed to bromoform.
Stewart et al. (1979) assessed the toxlclty of bromoform to larvae of
the oyster, C_. vlrglnlca. Tests were conducted at 26-29°C for 48 hours 1n
aluminum foil-capped 1 I glass beakers containing 1 9. of test solution.
Each beaker was Inoculated with -1500 freshly spawned and fertilized oyster
eggs to begin the test. Mortality among exposed larvae was determined by
screening larvae from test solutions, resuspendlng In 250 ml of seawater
and examining subsamples of this solution In a Sedgewlck-Rafter Cell.
0125d -19- 09/27/88
-------
Studies were repeated 5 times at 1-week Intervals. The Investigators
reported >90, -83, -75, 50 and -42% survival among larvae exposed to
bromoform at Initial concentrations of 0.0, 0.05, 0.1, 1.0 and 10.0 mg/l,
respectively, for the 48-hour exposure period. Bromoform levels fell to 30%
of their Initial concentration by the end of the study.
LeBlanc (1980) exposed the water flea, j). maqna. to bromoform In
delonlzed reconstituted well water at 22±1°C with a mean hardness of 173±13
mg/8. as CaCO . Test concentrations were not measured during the 48-hour
static test. Test vessels (250 ms, beakers) were covered with plastic wrap
secured with an elastic band. The reported 24- and 48-hour LC,-ns and 95%
confidence limits were 56 (44-68) and 46 mg/8. (42-51), respectively. The
NQEC was <7.8 mg/i.
Kerster and Schaeffer (1983) assessed the teratogenlc effects of bromo-'
form In brine shrimp, Artemla sallna. Evidence for teratogenesls 1n this
assay was derived from disturbances 1n elongation development of stage I to
stage III nauplll during the first 24-48 hours after hatching at 25°C.
Inhibition of elongation by >20% In bromoform-exposed nauplll compared with
elongation of control nauplll was considered Indicative of teratogenesls.
The Investigators reported that bromoform was teratogenlc to brine shrimp
nauplll at concentrations of 0.25-25 ppm, but that the assay was not very
sensitive with high an1mal-to-an1mal variability.
Richie et al. (1984) determined the toxlclty of bromoform to larval
mosquitoes, Aedes aeqyptl. Exposure of larvae to bromoform was conducted In
14.5xl.3-cm screw cap culture tubes at 29°C, with a single larvae 1n 5 mi
of solution/tube with 10 tubes/treatment. Test larvae were newly-hatched,
first Instar stages. The Investigators reported 0.5, 1.0 and 24-hour
LCS of 250, 80 and 75 ppm, respectively.
0125d
-20-
09/27/88
-------
4.1.2. Chronic Effects on Fauna.
4.1.2.1. TOXICITY — Haddock and Kelly (I960) examined the potential
of an Ui vitro SCE assay 1n leukocytes from the marine oyster toadflsh,
Qpsanus tag, as a mechanism to detect waterborn mutagens and carcinogens.
Leukocytes were obtained from samples of whole blood collected from living
fish. Cells were cultured 1n an appropriate medium for 12 hours at 25°C
before the addition of bromoform dissolved In a balanced salt solution.
Cultures were harvested 3-5 days after the Introduction of bromoform. The
Investigators reported that exposure of dividing leukocytes to bromoform at
0.1 and 400 yg/ml did not result 1n an Increased rate of SCE, and specu-
lated that the genetic activity of bromoform may be detectable at higher
concentrations or require metabolic activation In an in vivo assay.
Ward et al. (1981) assessed the chronic toxlclty of bromoform to embryos'
and juveniles of sheepshead minnows, £. varlegatus. Exposure of embryos
continued until all had either hatched or died. Juveniles from hatched
embryos were exposed to bromoform for 28 days. Embryos and juveniles were
exposed to bromoform diluted with natural seawater 1n an Intermittent-flow
system delivering 1 l per cycle at a rate of 4-7 cycles/hour. Juveniles
were fed live brine shrimp nauplll dally. Toxicant concentrations were
measured weekly. Test endpolnts were percent hatching success and juvenile
mortality. Salinity of seawater during the study ranged from 21-28/ma,
with a mean temperature of 30°C. Mean bromoform concentrations were 52-89%
of nominal concentrations, ranging from 1.6-15 mg/l. The Investigators
reported that exposure to <15 mg/l had no effect on hatching success or
growth of surviving juveniles. Concentrations >8.5 mg/l significantly
Increased mortality among juveniles, producing an estimated HATC of >4.8 to
<8.5 mg/l.
0125d -21- 11/09/88
-------
4.1.2.2. BIOACCUHULATION/BIOCONCENTRATION — Anderson et al. (1979)
and Gibson et al. (1979a,b,c, 1981) monitored the bloaccumulatlon and
depuration of bromoform In clams, £. stamlnea and M. mercenarla. oysters, £.
vlrglnlca, shrimp, P. aztecus. and menhaden, B. tyrannus. Holding and
exposure regimens were Identical to those described above for acute toxldty
testing of bromoform with- these species. P. stamlnea was tested separately
from the other species, which were exposed In a common chamber at concen-
trations ranging from 1-20 rng/i. Exposure concentrations for the other
molluscs ranged from 0.03-0.99 mg/i, and for menhaden and shrimp,
0.03-0.29 mg/fc. The Investigators reported that the clams and oysters had
tissue concentrations approximately equal to the water concentrations for
the 28 days of the exposure phase. Menhaden and shrimp, however, concen-
trated bromoform 3- to 50-fold above the exposure concentration, although
body burden levels tended to plateau at 0.4 vg/g tissue. Depuration of
bromoform from tissues of exposed organisms was very rapid, with negligible
levels present within 2 days of the cessation of exposure.
Scott et al. (1980) assessed the uptake of chlorlnatlon by-products In
the American oyster, £. vlrglnlca. during short-term exposures. Oysters
were acclimated to running seawater (25 I/hour) for 15 days In experi-
mental chambers before the Introduction of chlorine-produced oxldants (free
plus combined chlorine, bromine and other residual oxldants} at a concentra-
tion of 0.18 mg/8. for 96 hours. Bromoform concentrations ranged from
0.93-3.27 (mean = 2.03) yg/l. Water temperature ranged from
23.3-25.5°C. Salinity ranged from 18.0-21.5 ppt. The Investigators
reported a 3-fold bloconcentratlon of bromoform In oyster tissues. Bromo-
form concentrations In oyster tissues after 0, 24, 48, 72 and 96 hours were
0, 0, 12, 6.5 and 6 jig/kg, respectively. Tissue bromoform concentrations
0125d
-22-
01/17/89
-------
fell from 6 vg/kg to 0 pg/kg within 48 hours of the cessation of
exposure to chlorine-produced oxldants. The authors noted that the uptake
of bromoform by oysters could be seasonally dependent and based on physio-
logical changes In the oysters.
Subsequently, Scott et al. (1982, 1983) exposed oysters, C. vlrglnlca.
to chlorinated seawater for an extended duration. Tests were conducted In
replicate tanks (110x63x28 cm), with 50 oysters each receiving 250 «. of
unfUtered seawater/hour. Exposure concentration was 1.0 mg chlorlne/l as
Ca(QCl)?, producing mean bromoform concentrations of 28.3 and 21.9
ug/il In replicate chambers. Water temperature ranged from 26.5-30.0°C
and salinity ranged from 24-30 ppt. Measured levels of bromoform In oyster
tissue on days 0, 4, 8, 16 and 32 were 0, 100, 20, 35 and 65 ng/g wet
weight, respectively. Tissue levels of bromoform fell from -65 ng/g wet
weight to 0 ng/g wet weight within 4 days of the termination of exposure to
chlorinated seawater.
Based on the regression equation, log BCF = 0.76 log K - 0.23 (Lyman
et al., 1982) and a log KQW value for bromoform of 2.37 (see Section
1.2.), a BCF value of 37.3 Is estimated for this compound. This value Is 1n
agreement with the experimentally-derived BCFs of 3- to 50-fold, demonstrat-
ing that bromoform does not bloaccumulate significantly In aquatic organisms.
4.1.3. Effects on Flora.
4.1.3.1. TOXICITY — The 24-, 48- and 72-hour EC s (and 95%
confidence limits) for cultures of the freshwater green alga, Selanastrum
caprlcornutum. exposed to bromoform were 184 (21.3-51.1), 134 (82.6-250) and
121 ppm (86.4-169), respectively (U.S. EPA, 1978). Two 96-hour EC^s (and
95% confidence limits) reported for this species were 112 (75.4-155) and 116
ppm (81.2-160) (U.S. EPA. 1978). The 96-hour NOEC was reported to be 28.9
ppm (U.S. EPA, 1978).
0125d -23- 11/09/88
-------
The 24-, 48- and 72-hour EC5Qs (and 95% confidence limits) for
cultures of the saltwater alga, Skeletonema cos taturn, exposed to bromoform
were >28.9, 15.1 (12.0-18.1) and 13.5 ppm (7.54-30.3), respectively (U.S.
EPA, 1978). Two 96-hour EC5Qs (and 95% confidence limits) reported for
this species were 12.3 (5.92-25.8) and 11.5 ppm (5.35-24.9) (U.S. EPA,
1978). The 96-hour NOEC was reported to be 1.73 ppm (U.S. EPA, 1978).
EMckson and Hawkins (1980) assessed the effects of bromoform on photo-
synthesis by estuaMne phytoplankton. Taxonomlc classes present during
sampling Included Chlorophyceae, Cyanophyceae, and Badllarlophyceae.
Seawater was pumped to eight 37 S. aquaria located on an outdoor table at a
rate of 40 l/hour. Hater temperature ranged from 19.5-21.5°C and salinity
ranged from 20-24 g/fc. Exposure concentrations of bromoform ranged from
0.5-2.0 mg/a. Photosynthesis was determined by 14C uptake following'
exposure to bromoform for 24 hours. The Investigators reported no statisti-
cally measurable effects on 14C uptake by estuarlne phytoplankton exposed
to bromoform at the tested concentrations.
4.1.3.2. BIOCONCENTRATION — Pertinent data regarding the bloconcen-
tratlon potential of bromoform In aquatic flora were not located 1n the
available literature cited 1n Appendix A.
4.1.4. Effects on Bacteria. Pertinent data regarding the effects of
exposure of aquatic bacteria to bromoform were not located 1n the available
literature cited 1n Appendix A.
4.2. TERRESTRIAL TOXICOLOGY
4.2.1. Effects on Fauna. Pertinent data regarding the effects of
exposure of terrestrial fauna to bromoform were not located In the available
literature cited 1n Appendix A.
0125d
-24-
09/27/88
-------
4.2.2. Effects on Flora. Pertinent data regarding the effects of
exposure of terrestrial flora to bromoform were not located 1n the available
literature cited In Appendix A.
4.3. FIELD STUDIES
Pertinent data regarding the effects of bromoform on flora and fauna In
the field were not located 1n the available literature cited In Appendix A.
4.4. SUMMARY
The acute toxldty of bromoform to freshwater fish was determined for
blueglll sunflsh and common carp. The 96-hour LC5Qs for sunflsh exposed
to bromoform were 29.3 ppm (U.S. EPA, 1978) and 29 mg/8, (Buccafusco et
a!., 1981). The NOEC reported by U.S. EPA (1978) was 13 ppm. Mattlce et
al. (1981) and Trabalka et al. (1979) reported that the LC5Q for common
carp eggs exposed to bromoform was 52 mg/l. The acute toxldty of bromo-'
form to saltwater fish was determined for menhaden and sheepshead minnow.
The 96-hour LC™ for menhaden exposed to bromoform was 12 mg/t (Gibson
et al., 1979a,b, 1981). The 96-hour LC™ for sheepshead minnow exposed to
bromoform was 18 ppm In a static test {Heltmuller et al., 1981) and 7.1
mg/t In a flowthrough test (Ward et al., 1981). Heltmuller et al. (1981)
reported a NOEC of 2.9 ppm, while U.S. EPA (1978) reported a NOEC for
sheepshead minnow exposed to bromoform of 4.83 ppm and a MATC of >4.83 to
<8.5 ppm.
The acute toxldty of bromoform to molluscs was reported by Stewart et
al. (1979) and Gibson et al. (1979a,b, 1981). Survival among larvae of the
American oyster fell from >90 to -42% at bromoform concentrations from 0-10
mg/8.. Inadequate levels of mortality among adult clams and oysters
prevented calculation of LC5Qs for these spedes.
0125d -25- 09/27/88
-------
U.S. EPA (1978) and LeBlanc (1980) reported 48-hour LC^s for Daphnla
magna of 46.5 ppm, with a NOEC of <7.8 ppm. The 96-hour LC5Q for a
related species, Daphnla pulex, was 44 mg/i (Trabalka and Burch, 1978).
Richie et al. (1984) reported a 24-hour LC5Q of 75 ppm for larval
mosquitoes exposed to bromoform.
The 96-hour 1C for the saltwater crustacean, Hysldopsls bahla. was
24.4 ppm, while the NOEC was reported as 8.67 ppm (U.S. EPA, 1978). Gibson
et al. (1979a,b, 1981) reported a 96-hour LC& for shrimp of 26 mg/i.
Kerster and Schaeffer (1983) reported that bromoform was not teratogenlc to
brine shrimp nauplH at concentrations of 0.25-25 ppm.
Ward et al. (1981) reported that bromoform at concentrations of <15
mg/a. had no effect on hatching success or growth of surviving sheepshead
minnow juveniles, while concentrations >8.5 mg/i significantly Increased*
mortality among juveniles, producing an estimated HATC of >4.8 to <8.5.
Anderson et al. (1979), Gibson et al. (1979a,b,c, 1981) and Scott et al.
(1980, 1982, 1983) reported that bromoform was bloaccumulated 3- to 50-fold
by clams, oysters, shrimp and fish, but that depuration was very rapid (<2-4
days). A BCF value calculated from the log K for bromoform also
Indicates that bromoform does not bloaccumulate significantly.
U.S. EPA (1978) reported 96-hour EC5Qs for cultures of the freshwater
green alga, Selanastrum caprlcornutum. exposed to bromoform of 112 and 116
ppm, with a NOEC of 28.9 ppm. U.S. EPA (1978) also reported 96-hour EC^s
for cultures of the saltwater alga, Skeletonema costatum. exposed to
bromoform of 12.3 and 11.5 ppm, with a NOEC of 1.73 ppm.
0125d
-26-
01/17/89
-------
5. PHARMACOKINETICS
5.1. ABSORPTION
Absorption of bromoform occurs from the respiratory tract during Inhala-
tion, through the skin and from the gastrointestinal tract (von Oettlngen,
1955). Quantitative Information was not available on the rate or extent of
dermal or Inhalation absorption. Sax (1984), however, reported that dogs
exposed to bromoform at a concentration of 29,000 ppm experienced deep
narcosis after an 8-mlnute exposure, deep narcosis and recovery 1 day later
after a 30-mlnute exposure and death following a 1-hour exposure. Merzbach
(1928) also reported that a dog exposed to bromoform at a level of 56,000
ppm became deeply anesthetized after 20 minutes and died after 1 hour.
Dykan (1962, 1964) described toxic effects In rats and rabbits caused by
exposure to bromoform fumes. Collectively, these data suggest that substan-'
tlal and rapid absorption occurs from the respiratory tracts of several
species.
Gastrointestinal absorption In mice was determined by Mink et al.
(1986). Commercially synthesized 14CHBr3 was diluted In corn oil and
administered by gavage In single doses of 100 mg/kg for rats and 150 mg/kg
for mice. Test animals (adult male Sprague-Dawley rats and adult male
B6C3F1 mice) were fasted 16 hours overnight before treatment. Recovery of
the labeled carbon was evaluated after administration of a single dose of
the test substance. At 8 hours after treatment, 75.5% of the total 14C
administered was recovered from the rats: 66.9% expired as parent compound,
4.3% as carbon dioxide, 2.2% In urine and 2.1% 1n selected organs previously
determined to be the only ones with levels of radiation above background.
0125d -27- 09/01/89
-------
From the mice, 62.2% was recovered: 5.754 expired as parent compound, 39.7%
as carbon dioxide, 4.6% In urine and 12.2% In selected organs. Fecal
excretion of bromoform or Us metabolites was not estimated. Graphs
suggested that most of the expiration of radioactivity had occurred by -5
hours postdoslng for mice and 2 hours postdoslng for rats. These data
suggest that gastrointestinal absorption Is rapid, and that total
gastrointestinal absorption Is at least 75.5% of a single gavage dose In
rats and 62.2% In mice.
5.2. DISTRIBUTION
Parra et al. (1986) reported that bromoform distributed preferentially
to adipose tissue of 24-hour fasted adult male Sprague-Dawley rats given a
single gavage dose of 12 mg/kg 1n distilled water. At 15 minutes after
treatment, levels 1n fat (-8800 ng/g fresh tissue) were -1 order of magnl-'
tude greater than those In blood (-820 ng/g). Somewhat lower levels were
found In kidney (740 ng/g), brain (-570 ng/g) and liver (-30 ng/g). Levels
In the liver declined to below detection limit by 1 hour, presumably because
metabolism of bromoform occurred rapidly In this organ. Levels In the
remaining tissues other than fat declined to below detection by 4 hours. At
4 hours, levels In fat had declined to 1570 ng/kg. The Investigators
concluded that distribution and elimination of bromoform occurred rapidly.
Mink et al., (1986) evaluated distribution of radlolabeled bromoform In rats
and mice. At an unspecified time after Intragastrlc Intubation of
14CHBr_ 1n rats and mice (see Section 5.1.), -2% of the total radio-
O
activity administered was found 1n the urinary bladder, brain, kidneys,
liver, lungs, skeletal muscle, pancreas, stomach (without contents) and
thymus. In addition, -10% was found 1n the blood of the mice. The Investi-
gators reported that these organs were the only ones that contained a
significant amount of radioactivity above the background level. Organs with
0125d
-28-
09/01/89
-------
the highest residual radioactivity levels were the stomach without contents,
nonperfused liver, and kidneys for both rats and mice. Leuze (1922),
however, reported that after Inhalation exposure, higher concentrations of
bromoform were found In the brain than 1n the blood or liver.
5.3. METABOLISM
Intraperltoneal or Inhalation administration of trlhalomethanes to rats
resulted 1n elevated blood CO and carboxyhemoglobln levels (Anders et al.,
1978; Fodor and Roscovanu, 1976) and lowered liver GSH levels (Pohl et al.,
1980a). Moody and Smuckler (1986), however, detected a significant Increase
In GSH levels In rats administered bromoform by gavage at a level of 1000
mg/kg. Bromoform 1s metabolized to CO by a cytochrome P450-dependent
mixed-function oxldase system In rat liver mlcrosomal fraction (Ahmed et
al., 1977; Stevens and Anders, 1979; Ahmed et al., 1980). This metabolism'
requires NAOPH, molecular oxygen and a sulfhydral compound (e.g., GSH) for
maximum activity (Ahmed et al., 1977; Stevens and Anders, 1979). This
GSH-dependent CO production Is part of the detoxification pathway for bromo-
form and haloforms In general (Stevens and Anders, 1981). The fate of the
carbon In bromoform and the molecular oxygen during metabolism was studied
In vitro by Stevens and Anders (1979). 13CHBr« and 12CHBrQ 1ncu-
o o
bated 1n the presence of 180p produced 13CO and C,B0, respectively.
A primary Isotope effect was observed when C2HBr. served as the
substrate.
The overall metabolic pathway (Figure 5-1) Includes the role of dlbromo-
carbonyl, proposed as a toxic Intermediate In the metabolism of bromoform,
In the formation of OZT, CO and CO- (NTP, 1988). Dlbromocarbonyl Is an
Intermediate In the production of CO from bromoform as shown by the detec-
tion of OZT when bromoform was Incubated with cystelne. The source of the
0125d -29- 09/01/89
-------
Br
I
H—C—Br
Br
I Cytochrom* MSO
Br
HO—C—Br
Sr
Tribromomtttwnol
\
Nontnzymatic
-HBr s
i /
0
\
GSH k
/\ -HBr'
COOH
H2N~W
COOH /
>V
2H8r * HN S
>yX
0
Br
Br
Oibromocartaonyl
IH^O \
r
C02
r
+ 2HBr
Covad ntly binrfi (acytatn)
tiuu* nudtophiltt
O
__ * _ GSH _»,_ -^ .,_
GS—C —Br » GSSG + CO + HBr
2GSH
O
GS_C_SG * 2HBr
2-O»othiaiolidmt-4-carboxylk acM
FIGURE 5-1
Proposed HetabolU Pathway for Bronoform
Source: NTP, 1988
0125d
-30-
09/27/88
-------
carbonyl carbon was shown to be bromoform, because [13C]OZT was formed
when 13C bromoform was the substrate. The oxidized form of GSH (GSSG) 1s
apparently produced when COX,,, formed during oxldatlve metabolism of
halocarbons, react with GSH {Pohl et al., 1980a). GSH becomes oxidized to
GSSG and CO Is formed from dlbromocarbonyl In a ratio of 2:1:1 GSH:GSSG:CO
(Stevens and Anders, 1979).
The tox1c1ty of trlhalomethane metabolites may be related to their
reducing mechanisms (Tomasl et al., 1985; Wolf et al., 1977). Free radical
Intermediates were found during aerobic and anaerobic Incubation of bromo-
form w,1th Isolated rat hepatocytes (Albano et al., 1985; Tomasl et al.,
1985). Poyer et al. (1986) also detected a dlbromomethyl radical
(•CHBr^) in rat liver I1p1d extracts 2 hours after Ingestlon of bromo-
form at a level of 1.3 mmol/kg (~33Q mg/kg) body weight. The bromoform was
administered along with phenyl-t-butyl nltrone (a spin trapping agent) 1n a
corn oil-phosphate buffer mixture by oral gavage. This radical was also
detected 1n in vitro Incubation of bromoform with Hver mlcrosomes from the
mouse, chicken and turkey. Wolf et al. (1977) suggested that the radical
may lead to llpld peroxldatlon and destruction of cell membranes, and NTP
(1988) suggested that covalent binding of cellular macromolecules by
dlbromocarbonyl (the Intermediate) may be the cause of liver toxldty.
Many factors may Inhibit or enhance the rate of bromoform metabolism jji
vitro and Jm vivo. The rate of conversion of bromoform to CO was Inhibited
in vivo or in vitro by pretreatlng rats with cobaltous chloride (Ahmed et
al., 1977), SKF 525-A (a hepatic mlcrosomal cytochrome P450 Inhibitor)
(Ahmed et al., 1977; Anders et al., 1978), dlethylmaleate (also an Inhibitor
of the cytochrome P450-dependent oxidation of some xenoblotlcs) (Stevens and
Anders, 1981) and CO (Buther et al., 1986). The jm vivo and U^ vitro rate
0125d -31- 11/09/88
-------
of conversion was Increased by pretreatlng rats with phenobarbHal (Ahmed et
al., 1977; Wolf et al., 1977; Anders et al., 1978) or 3-methylcholanthrene
(Ahmed et al., 1977). Pohl et al. (1980b) reported that phenobarbltal
pretreatment of rats Induced liver mlcrosomal formation of COBr from
bromoform.
Dlethylmaleate pretreatment of male Sprague-Dawley rats 30 minutes
before 1ntraper1toneal Injection of [2H]bromoform (deuterium-substituted)
also lessened the effect of deuterium substitution on the metabolism of
bromoform to CO (Stevens and Anders, 1981). There was no significant
"difference between the blood CO concentrations produced by the deuterium
substituted form of bromoform and the [1H]bromoform In dlethylmaleate
pretreated rats, whereas Anders et al. (1978) detected lower blood CO levels
In nonpretreated rats administered 2H-bromoform (deuterium-substituted)'
compared with those administered ^-bromoform.
Pohl et al. (1980b) also determined that deuterium-labeled bromoform 1s
less hepatotoxlc than CHBr^. The C-H cleavage 1s the rate limiting step
1n the blotransformatlon of bromoform to hepatotoxlc metabolites (NTP, 1988;
Anders et al., 1978). Deuterium (which presumably forms a stronger C-H
bond) has been shown to decrease the rate of bromoform metabolism; homolytlc
scission of the C-H bond Is critical for aerobic haloform metabolism. In a
reductive environment, however, deuterium substitution does not signifi-
cantly affect the rate of free radical formation. This suggests that there
Is an electron transfer directly from the cytochrome to the halocompound
(bromoform), with the subsequent formation of a hallde 1on and the free
radical (Tomasl et al., 1985), a mechanism not dependent on lysis of the C-H
bond.
0125d
-32-
09/01/89
-------
Excretion data {Section 5.4.) suggest substantial quantitative differ-
ences between species In the metabolism of bromoform.
5.4. EXCRETION
H1nk et al. (1986) studied the excretion of radlolabeled bromoform In
orally treated rats and mice (see Section 5.1.). The urine of both the mice
and rats contained <5% of the total radlolabel 8 hours after gavage adminis-
tration and <1Q% after 36-48 hours. Most of the bromoform was eliminated
through the lungs In the expired air within 8 hours postdoslng for both the
rats and the mice. The mice eliminated 39.68% of the total 14C-bromoform
as 14CO_ and 5.70% as the unmetabollzed parent compound. The rats,
however, eliminated 4.3% as 14C02 and 66.9% as the parent compound.
These data suggest that mice metabolize bromoform more extensively than do
rats. The half-lives of bromoform were 8 hours 1n mice and 0.8 hoursv1n'
rats, lucas (1928) also evaluated excretion of bromoform and Us metabo-
lites 1n the urine. Several male rabbits were Injected with a 50:50
bromoform-ol1ve oil mixture per rectum and were catheterlzed for several
days to collect urine samples. The bromoform was recovered as Inorganic
bromide In the urine In amounts ranging from 0.3-1.2%.
5.5. SUMMARY
Bromoform 1s absorbed from the respiratory tract, skin and gastro-
intestinal tract (von Oettlngen, 1955), apparently quite readily from the
respiratory and gastrointestinal tracts. Once absorbed, bromoform and Its
metabolites are distributed rapidly, with highest levels located In adipose
tissue and blood (Parra et al., 1986). Substantial levels are also found In
several other organs Including the brain. Elimination occurs rapidly from
all tissues Including fat (Parra et al., 1986). Metabolism of bromoform
occurs predominantly In the liver by a cytochrome P450 oxldase system to CO
0125d -33- 11/09/88
-------
and C02 {Ahmed et al., 1977, 1980; Stevens and Anders, 1979). Dlbromo-
carbonyl 1s a likely toxic Intermediate In this pathway (NTP, 1988). Mice
appear to metabolize bromoform by this pathway more completely than do rats
(M1nk et a!., 1986). Bromoform metabolism depletes liver GSH (Pohl et al.,
1980a) because this system Is stimulated by sulfhydral compounds (e.g., GSH)
(Stevens and Anders, 1979; Ahmed et al., 1980). Bromoform also appears to
be metabolized through a reductive pathway that produces free radical Inter-
mediates. Excretion of bromoform and Its metabolites occurs to a small
extent through the urine and to a much larger extent through the lungs In
mice, rats (Mink et al., 1986) and rabbits (Lucas, 1928).
012Sd
-34-
11/09/88
-------
6. EFFECTS
6.1. SYSTEMIC TOXICITY
6.1.1. Inhalation Exposure.
6.1.1.1. SUBCHRONIC — Dykan (1962) administered bromoform to rats at
a level of 0.25 mg/4 (250 mg/m3) air, 4 hours/day for 2 months. Dis-
orders were observed In the glycogenesls and protein prothrombln functions
of the liver and the filtration capacity of the kidneys. Further Informa-
tion was not available In the abstract of this study.
6.1.1.2. CHRONIC -- Dykan (1964) evaluated the effects of chronic
Intoxication (details of administration not available from the abstract) of
bromoform on rats and determined that the threshhold concentration was 0.05
rag/a, (50 mg/m3}. Bromoform-contalnlng metabolites were produced and
slowly excreted from the animal. Dykan (1964) also stated that workers In'
bromoform production exhibited changes 1n the central nervous system and
liver.
6.1.2. Oral Exposure.
6.1.2.1. SUBCHRONIC — In a study sponsored by the NTP (1988), bromo-
form (95-97% pure) was administered In corn oil by gavage to groups of 10
male and 10 female F344/N rats and equal numbers of B6C3F1 mice 5 days/week
for 13 weeks. The rats received bromoform at doses of 0 (vehicle control),
12, 25, 50, 100 or 200 mg/kg body weight and the mice received doses of 0
(vehicle control), 25, 50, 100, 200 or 400 mg/kg. Animals were observed
dally and killed when moribund. Necropsy was performed on all animals
except those severely autolyzed or cannibalized.
Clinical observation of the rats revealed no mortalities and no signifi-
cant difference between final mean body weights of dosed and vehicle control
rats. All male rats receiving 100 or 200 mg/kg and all females receiving
0125d -35- 11/09/88
-------
200 mg/kg were lethargic. Also, all males In the highest dose group had
diarrhea. H1stopatholog1cal evaluation of rats revealed hepatocellular
vacuollzatlon In males 1n 10/10 rats receiving 200 mg/kg, 8/10 receiving 100
mg/kg, 8/10 receiving 50 mg/kg, 5/10 receiving 25 mg/kg, 6/10 receiving 12
mg/kg and 3/10 In the vehicle control group. The incidence of hypatocellu-
lar vacuollzatlon reached statistical significance at 50 mg/kg (8/10; p=0.03
Fisher Exact test computed at SRC). Vacuoles were more numerous In hepato-
cytes from rats In the highest dose group. Lesions were not observed 1n
female rats.
Clinical observation revealed mortality in one female mouse that
received 100 mg/kg of bromoform; cause of death was not reported. Males 1n
the highest dose group had final mean body weights 854 lower than those of
vehicle controls. Hlstopathologlcal evaluation revealed dose-related cyto-'
plasmlc vacuollzatlon of hepatocytes In the livers of 8/10 males In the 400
mg/kg dose group and 5/10 males in the 200 mg/kg dose group. The Incidence
In the control group was not reported. Lesions were not observed in female
mice.
The RES was evaluated In 7-day-old male and female ICR mice administered
bromoform by oral gavage for 90 days at dose levels ranging from 0.2-125
mg/kg (Munson et al., 1977). Blood clearance of I125-labeled LIsteMa
monocytoqenes was decreased by 2354 1n males receiving the lowest dose of
bromoform. The accumulation of L^ monocytogenes was measured 1n the liver
by determining specific activity. A dose-related depression 1n specific
activity was observed in females and males that reached 43 and 28%, respec-
tively, at 125 mg/kg. The decrease in blood clearance and specific activity
Indicated that there was a reduced uptake and disposal of phagocytic cells
required for the removal of the U monocytogenes pathogen. Munson et al.
0125d
-36-
09/27/88
-------
(1977) concluded that there was a slight alteration In RES function after
administration of bromoform. Munson et al. (1978) also reported a dose-
dependent suppression In hepatic phagocytosis In female and male mice admin-
istered 0.3, 12.5 or 125 mg/kg/day. The level at which significant suppres-
sion first occurred Is difficult to assess.
Balster and Borzelleca (1982) evaluated the behavioral toxlclty of
bromoform following oral gavage 1n a suspension using a vehicle of 1:8
Emulphor:water. Groups of 6-8 adult male ICR mice were administered bromo-
form at levels of 0.9 or 9.2 mg/kg/day for 90 days. There was no effect on
bar clinging, exploratory behavior or motor coordination. Mice were also
administered bromoform at a level of 100 or 400 mg/kg/day for 60 days or at
a level of 100 mg/kg/day for 30 days. Operant behavior (response and
reinforcement rates were decreased) was clearly Impaired at both of the dose'
levels given for 60 days. Some tolerance developed to the Initial operant
behavior effects seen In this study. No effect on passive-avoidance
learning was observed In the 30-day experiment.
Chu et al. (1982a) evaluated the reversibility of toxlcologlcal changes
produced by some trlhalomethanes. Groups of 20 male and 20 female weanling
Sprague-Dawley rats were administered bromoform and Emulphor 1n their
drinking water for 90 days at a level of 0 (tap water control), 0 (vehicle
control), 5, 50, 500 or 2500 ppm. Drinking water Intake decreased In a
concentration-related manner. Based on water Ingestlon, the Investigators
estimated dosage at 0, 0.11-0.17, 1.2-1.5, 8.9-14 and 29-55 mg/rat/day.
After 90 days, 10 rats from each group were killed and the remaining rats
received plain tap water for another 90 days.
Mortality was observed 1n one male rat 1n the highest dose group, two
females In the 500 ppm group and one female 1n the 5 ppm group. In the
0125d -37- 09/27/88
-------
groups allowed to recover, mortality was observed 1n one female In each
group that had received 50 ppm, 500 ppm and 2500 ppm bromoform. Emaciation
and weight loss were observed before death; microscopic examination
suggested starvation as the cause of death.
According to Chu et al. (1982a), there was no significant effect on body
weight changes during treatment or after the 90-day recovery period for
either sex. Male rats receiving bromoform at 2500 ppm experienced sup-
pressed food consumption, but this effect was not apparent after the 90-day
recovery period. Other 'effects reported 1n both sexes at 2500 ppm were
significantly decreased serum LDH activities, noted during both, the exposure
and recovery periods, and significantly decreased lymphocyte counts observed
only during the recovery period. The biological significance of these
observations Is unclear. Mild hlstopathologlc lesions were observed 1n the*
livers and thyroids of both control and exposed rats. Although It appeared
that the number of rats bearing lesions was greater at 2500 ppm, the Inci-
dence was quite variable and not statistically significant. Significantly
greater severity was observed In the liver lesions In males at 2500 ppm and
1n females at >500 ppm after exposure. There was no significant difference
In the severity of these lesions after the recovery period.
Borzelleca (1983) studied the effects of bromoform administered In the
drinking water on male and female CO-1 mice (group sizes not reported).
Systemic toxlcologlcal parameters examined Included hematology, numerous
clinical chemistries, Immunology, extensive behavior evaluation, neurocheml-
cal status and organ weights. Dosages Ingested by adult male mice were
estimated by the Investigators at 0.2, 125 and 250 mg/kg/day for 90 days.
There were no significant findings at any of these levels. Dosage and
response data on female mice were not reported.
0125d
-38-
09/27/88
-------
Chu et al. (1982b) evaluated the toxklty of bromoform (96% pure) In
groups of 10 weanling male Sprague-Dawley rats administered the test
substance wHh 1% Emulphor (a surfactant) In drinking water at levels of 0
(tap water), 0 (vehicle control), 5, 50 or 500 ppm (w/v) for 28 days.
Dosages were estimated by the Investigators at 0, 0, 0.13, 1.5 and 14
mg/rat/day. There were no treatment-related mortalities and no effects on
the growth rate and food Intake at any level. Necropsy evaluation revealed
a slight Increase 1n relative kidney weight 1n the 500 ppm group. No
changes were observed 1n serum biochemical parameters (sodium, potassium,
phosphate, total bH1rub1n, alkaline phosphatase, GOT, total protein,
calcium, cholesterol, glucose, uric acid, LOH and SDH levels), hepatic
mlcrosomal enzyme activities and hlstologlcal appearance of >25 major organs
and tissues.
In a test of the effect of haloalkanes on humoral and cell-mediated
Immunity, Schuller et al. (1978) administered bromoform by gavage for 90
days (schedule not reported) to 7-day-old male and female ICR mice at levels
of 0.2, 12.5 or 125 mg/kg. Bromoform did not appear to affect delayed
hypersensHlvHy, humoral Immune response, liver function, kidney function
or hematology 1n the mice.
6.1.2.2. CHRONIC -- In a chronic oral toxlclty study sponsored by NTP
(1988), groups of 50 male and 50 female F344/N rats and 50 female B6C3F1
mice were administered bromoform 1n corn oil by gavage at levels of 0
(vehicle control), 100 or 200 mg/kg, 5 days/week for 103 weeks. Groups of
50 male B6C3F1 mice were slmllarUy administered bromoform at levels of 0
(vehicle control), 50 or 100 mg/kg.
Compound-related mortality was observed only In the male rats receiving
200 mg/kg/day. Lethargy was observed In treated male and female rats, and
0125d -39- 11/09/88
-------
aggressiveness was also observed In treated male rats. Mean body weights of
low- and high-dose males and high-dose female rats were substantially lower
than those of vehicle controls by the end of the study (between 5 and 14%
lower, 12 and 28% lower and 10 and 25% lower, respectively), Histopatho-
loglcal examination revealed an Increased Incidence of chemical-related,
nonneoplastlc lesions in the livers of treated rats. Dosed female rats
displayed fatty liver changes. Increased mixed cell foci, decreased baso-
phlllc foci and decreased necrosis of the liver when compared with control
animals. Chemical-related effects 1n dosed male rats included fatty change,
chronic inflammation and necrosis of the liver, and an Increased Incidence
of gastric ulcers and chronic inflammation of the lungs.
There was no significant difference in mean body weights of treated male
mice; however, weights of dosed female mice were 5-16% lower than those of'
vehicle controls. Hlstopathologlcal examination revealed hyperplasla of the
glandular stomach 1n treated males, cytoplasmlc vacuollzation of hepatocytes
in treated females and thyroid folllcular cell hyperplasla In high-dose
females.
6.1.3. Other Relevant Information. Table 6-1 summarizes LD5Q and
LC50 data. Oral LD5Q values for both rats and mice ranged from
1147-2500 mg/kg; there was no partlculaMly sensitive species or sex.
IntraperHoneal LD5Q values ranged from 414 yl/kg (1196 mg/kg) for male
rats (comparable with oral data} to 9274 mg/kg for unspecified mammals.
According to Sax (1984), the Inhalation LC&0 value Is 12,100 mg/m3 for
mammals (length of time not stated).
Results of acute oral administration of bromoform to rats Include:
ataxla and lethargy (Chu et a!., 1980; NTP, 1988); plloerection, flaccid
muscle tone and hypothermia (Chu et al., 1980); altered hematologlcal
0125d
-40-
01/17/89
-------
and
TABLE 6-1
Values for Bromoform
Species
ICR Swiss mice/
CD-I mice
ICR Swiss mice/
CD-I mice
Rats
Sprague-Dawley
rats
Sprague-Dawley
rats
Sprague-Dawley
rats
Mammals
Mammals
Dose or
Sex Concentration
(Vehicle)
« 1400 mg/kg
{Emulphor:
alcohol :sa!1ne)
F 1550 mg/kg
{Emulphor:
alcohol:sa!1ne)
M 2500 mg/kg
(corn oil)
M 1388 mg/kg
(Emulphor:
water)
F 1147 mg/kg
(Emulphor:
water)
M 1196 mg/kg
(corn oil )
NR 9274 mg/kg
(NR)
NR 12,100 mg/m3
(NR)
Value Reference
oral LD5Q Bowman et al.,
1978;
Borzelleca,
1983
oral LD5Q Bowman et al.,
1978;
Borzelleca,
1983
oral LD5Q Torkelson and
Rowe, 1981
oral LDso Chu et al.,
1982b
oral LDso Chu et al.,
1982b
Intraperltoneal Agarwal and
LD50 Mehendale, 1983
Sax, 1984
inhalation Sax, 1984
*Length of exposure not specified
NR = Not reported
0125d
-41-
09/27/88
-------
values, hlstologlcal changes In the kidneys and an activation of mlcrosomal
AH activity In females (Chu et al., 1982b); and numerous liver abnormalities
defined 1n part by an Increase In Upld dlene conjugates (Reynolds, 1972),
abnormal endoplasmlc retlculum (Nlshlmura et al., 1980), Increase 1n mlcro-
somal protein and RNA (Moody et al., 1981), decrease In protein content In
males (Chu et al., 1982b), enlargement (Chu et al., 1980), and a decrease In
cytochrome P450 and ALA-dehydratase levels and an Increase In porphyrln and
glutathlone levels (Moody and Smuckler, 1986). A decrease 1n GSH In rats
was reported by Pohl et al. (1980a).
Acute oral administration of bromoform to mice resulted In ataxla and
lethargy (Bowman et al., 1978; NTP, 1988); fatty Infiltration of the liver,
pale kidneys and hemorrhaglng of the lungs, adrenals and brain (Bowman et
al., 1978); Inhibited renal slice uptake of PAH, elevated SGPT values and'
numerous kidney and liver abnormalities (Condle et al., 1983); decrease In
prothrombin time, glucose and BUN levels, an Increase In SGOT and body
weight and a significant depression In humoral and cell Immunity (males),
and decreased body weight and relative and absolute spleen weights as well
as an Increase In SGOT (females) (Munson et al., 1982). In addition, an
Increase In relative and absolute liver weights for both sexes was reported
by Munson et al. (1982). Borzelleca (1983) also reported "significant
findings" 1n the liver, kidney and thymus of adult male CD-I mice after
administration of bromoform by gavage at a level of 0.2, 125 or 250
mg/kg/day for 14 days.
Other routes of administration were studied by several Investigators.
Lucas (1928) reported liver damage (fatty degeneration, swelling of portal
zone cells, necrosis and proliferation of fibrous connective tissues) In
rabbits after bromoform administration through the rectum. Acute Inhalation
0125d
_42_
09/27/88
-------
exposure resulted 1n deep narcosis and death tn a dog exposed to a level of
29,000 ppm for 1 hour (Sax, 1984), and disorders In the central nervous
system in rabbits exposed to a concentration of 11-13 mg/it (11,000-13,000
mg/ma) (time not specified In the abstract) and a protective Inhibition of
the cerebral cortex, disorders In protein metabolism and glycogen synthesis
In the liver, disorders of filtration capacity of the kidneys, and vascular
disorders and dystrophk changes In the liver and kidneys of rats exposed to
vapors at a concentration of 2.5 mg/a (2500 mg/m3) for 10 days (Dykan,
1964).
In addition, neural and behavioral toxlclty was Investigated. Parra et
al. (1986) reported an Increase In the central amlnerglc metabolic activity
In the brain 1n fasted male Sprague-Dawley rats administered bromoform In 5
mi water by gavage. In a study 1n which adult male ICR mice were admlnls-'
tered bromoform 1n a 1:8 Emulphor:water mixture by gavage at 0.9 or 9.2
mg/kg/day, Balster et al. (1979) and Balster and Borzelleca (1982) reported
no observed behavioral effects following either a single dose or a series of
14 doses.
Agarwal and Hehendale (1983) and KUngensmHh and Mehendale (1981)
tested the potentlatlon of chlordecone on bromoform toxlclty and concluded
that bromoform Is not a potent hepatotoxln and that chlordecone does not
potentiate Us effects. Hopkins and Krantz (1968) reported that an Intra-
venous dose of bromoform as an o1l~tn-water mixture sensitized female
mongrel dog myocardium to eplnephrlne.
Koyama and Nakazawa (1986) reported that bromoform Inhibited the Incor-
poration of [3H]glycerol Into tMacylglycerol In an j£ vitro llpld metabo-
lism experiment with male Wlstar rat liver slices. Mochlda and Yamasakl
(1984) reported an Inhibitory effect from bromoform on growth of cultured
0125d -43- 09/27/88
-------
human cells and African green monkey kidney cells. Fraga et al. (1987)
reported a significantly greater amount of thlobarbHurlc acid-reactive
substances released from kidney slices Incubated with bromoform. This
release Is a measure of Upld peroxldatlon. Kroneld (1987) determined that
bromoform reduced phytohaemagltit 1 nine stimulation 1n human peripheral blood
lymphocytes and decreased the viability of human uroeplthellal cells.
6.2. CARCINOGENICITY
6.2.1. Inhalation. Pertinent data regarding the Inhalation carclnogen-
Iclty of bromoform were not located In the available literature cited In
Appendix A.
6.2.2. Oral. There was no evidence of carclnogenlclty In a feed study
with male and female Hlstar rats exposed for 24 months to mlcroencapsulated
bromoform (Kurokawa, 1987). Further Information on this study was not
available. In a study sponsored by NTP (1988), groups of 50 male and 50
female F344/N rats and 50 male and 50 female B6C3F1 mice were administered
bromoform In corn oil 5 days/week for 2 years by oral gavage at levels of 0
{vehicle control), 100 or 200 mg/kg (rats and female mice) or at levels of 0
(vehicle control), 50 or 100 mg/kg (male mice) (see Section 6.1.2.).
Neoplastlc lesions (edenomatous polyps or adenocardnomas) attributed by NTP
(1988) to bromoform were observed In the large Intestine of three male rats
In the high-dose group, one female rat In the low-dose group and eight
female rats 1n the high-dose group (Table 6-2). No neoplastlc lesions were
observed 1n the treated mice or 1n the vehicle control groups (Table 6-3).
The lower Incidence of lesions In the high-dose male rats compared with
high-dose females may be due to the reduced survival of this group of ani-
mals. Survival was reduced significantly at 91 weeks and the first large
Intestinal tumor was not seen until 71.3 weeks. Bromoform was not
0125d
-44-
09/01/89
-------
TABLE 6-2
Incidence of Tumors of the Large Intestine In
F344/N Rats Treated by Gavage with Bromoform (>95% pure) In
Corn 011 for 103 Weeks3
Sex
M
H
M
F
F
F
Exposure
vehicle control
100 mg/kg, 5 days/week
(71.4 mg/kg/day)
200 mg/kg, 5 days/week
(142.9 mg/kg/day)
vehicle control
100 mg/kg, 5 days/week
(71.4 mg/kg/day)
200 mg/kg. 5 days/week
Body Weight
(kg)
0.450
0.425
0.350
0.250
0.250
0.225
Tumor Incidence
(p value)
0/50 (p=O.Q08)b
(p=0.030)c
0/50
3/50 (p=0.028)b
(p=0.092)c
0/50 (p<0.001)b
(p<0.001)c
1/50 (p*0.461)b
(p=0.461)c
8/50 (p=0.003)b
(142.9 mg/kg/day) (p=0.004)C
QUALITY OF EVIDENCE
Strengths of Study: Compound of acceptable purity administered to both
sexes by a relevant route at two dose levels; adequate
number of animals Initiated; adequate duration of
exposure; comprehensive hlstopathologlcal and statis-
tical analysis. Other nonneoplastlc observations
suggest the HTD had been reached or exceeded.
Weaknesses of Study: Nonnatural mode of administration; reduced survival In
high-dose males.
Overall Adequacy: Adequate
aSource: NTP, 1988
bp values for Life Table Test
cp values for Logistic Regression Tests
0125d -45- 09/01/89
-------
TABLE 6-3
Incidence of Tumors of the Respiratory Tract In
86C3F1 Mice Treated by Gavage with Bromoform (>95% pure) In
Corn 011 for 103 Weeks3
Sex
Exposure
Body Weight
(kg)
Tumor Incidence
(p value)
F
M
M
F
F
vehicle control
vehicle control
50 mg/kg, 5 days/week
(35.7 mg/kg/day)
100 mg/kg, 5 days/week
(71.4 mg/kg/day)
100 mg/kg, 5 days/week
(71.4 mg/kg/day)
200 mg/kg, 5 days/week
(142.9 mg/kg/day)
0.40
0.38
0.40
0.40
0.34
0.32
11/50 (p=0.012)b
(p=0.009)c
8/50
7/50 (p=0.288)b
(p=0.236)c
2/49 (p=0.015)b
(p»0.015)c
3/50
2/50 (p=0.60)b
QUALITY OF EVIDENCE
Strengths of Study: Compound of acceptable purity administered to both
sexes by a relevant route at two dose levels; adequate
number of animals Initiated; adequate duration of
exposure; comprehensive hlstopathologlcal and statis-
tical analysis. Other nonneoplastlc observations
suggest the MTO had been reached or exceeded.
Weaknesses of Study: Nonnatural mode of administration; reduced survival 1n
treated females.
Overall Adequacy: Adequate
aSource: NTP, 1988
bp values for Life Table Test
cp values for Logistic Regression Tests
dp values for Fisher Exact Test
0125d
-46-
09/01/89
-------
carcinogenic to the kidneys of rats or mice. NTP (1988) concluded that
there was "some evidence of carcinogenic activity of bromoform for male
F344/N rats and clear evidence of carcinogenic activity for female F344/N
rats, based on Increased Incidence of uncommon neoplasms of the large
Intestine." There was no evidence of carcinogenic activity In the mice.
The authors speculated that the high reactivity of the dlbromocarbonyl
active Intermediate caused It to react with cellular nucleophlles too
rapidly to permit ONA acylatlon, which would otherwise result In neoplasms.
6.2.3. Other Relevant Information. Krayblll (1983) lists bromoform as a
suspected human carcinogen present In drlnklna water. According to Cantor
et al. (1978), there Is a positive correlation between levels of trlhalo-
methanes In drinking water and the Incidence of several human cancers
Including bladder and brain cancers In both sexes and non-Hodgk1ns lymphoma
and kidney cancer 1n males. Bromoform produced a statistically significant
(p<0.041) Increase In the number of pulmonary adenomas/mouse In strain A
mice following a total of 23 thrice-weekly IntrapeMtoneal Injections of the
test substance In Trlcaprylln at a level of 48 mg/kg/1njectlon (Thelss et
al., 1977); however, no Increase was observed at 100 mg/kg. There was no
effect on survival. Perelra et al. (1982a,b) determined that bromoform did
not Initiate GGTase-posltlve foci In the rat liver GTase-transformatlon test
at 1 mmol (253 nig)/kg or 0.8 mmol (202 mg)/kg following a 2/3 partial hepa-
tectomy and promotion with phenobarbltal. Perelra et al. (1982a) stated,
however, that carcinogens such as bromoform may have eplgenetlc rather than
genotoxlc mechanisms of action. Perelra (1983) also determined that bromo-
form 1s a potent Inducer of ornlthlne decarboxylase Induction activity.
Ornlthlne decarboxylase 1s an apparent prerequisite and a potential mole-
cular marker for tumor production In the skin and liver.
0125d -47- 10/25/89
-------
6.3. HUTAGENICITY
The results of several mutagenlclty and genotoxldty assays with
bromoform are presented 1n Table 6-4. Bromoform was mutagenlc 1n Salmonella
strains TA100 and TA1535 1n the absence of metabolic activation when the
assay was conducted In a desiccator (Simmon, 1977), but not In a "standard"
prelncubatlon assay {NTP, 1988). Positive gene mutation responses were also
reported In the mouse lymphome L5178Y TK forward mutation assay In the
absence of activation (NTP, 1988) and In the Drosophlla sex-linked recessive
lethal assay by feeding but not by Injection (Woodruff et al., 1985).
Bromoform was positive In the sister chromatld exchange (SCE) assay In
human lymphocytes treated In culture (MoMmoto and Koizumi, 1983) and
marginally positive 1n CHO cells In one of two laboratories without but not
%
with rat liver S9 activation (Galloway et al., 1985). Induction of SCEs was
also reported In mouse bone marrow cells (Morlmoto and Koizumi, 1983; NTP,
1988). The results In the chromosome aberration assay In CHO cells were as
for SCE; the same laboratory reported the high dose marginally positive In
the absence of metabolic activation (Galloway et al., 1985). Bromoform was
negative for chromosome aberrations but positive for mlcronuclel In bone
marrow cells of mice receiving single l.p. Injections.
6.4. TERATOGINICITY
Ruddlck et al. (1983) administered bromoform (96% pure) dissolved In
corn oil by gavage to groups of 15 mated Sprague-Dawley rats at a level of 0
(vehicle control), 50, 100 or 200 mg/kg/day from day 6-15 of gestation.
Extensive clinical _ and hlstologlcal parameters examined In the dams
Included: body weight; an extensive hematologlcal profile; liver, heart,
brain, spleen and kidney weights; and the presence of lesions In a large
number of organs. No evidence of maternal toxicHy was observed. On day 22
0125d
-48-
09/01/89
-------
—
^
o
en
i*_
0
JS C
UJ 4«»
«J VI
< »2
X
U
_
Ol
o>
X
0)
u
c
01
Ol
t*-
at
c
g
<3
Ol
c
o
Ol
de
o>
- E
4-" Ol
IB 4->
> VI
4-* fcO
U
*
c
o
*Q VI
1- O
•x a
c
Ol L.
go
a
gj
J
^
jj
A
»
t_
*S!
•** ^»
<9 C
1*
*
V*
w«
«c
*
P««
en
CO
i— C
a." E
Z CO
£*
13
VI tj
3 ra VI
VI i_ 1—
o> o >o
VI b_
ra -o
a — U
4- O VI
3 CL
CT 41 C 0
UJ 1- — Z
111 4-
91 0^ 0^ 0^
lit 1
Crt tO CO CO
k.
o
01 01 0) U
t — I— I— VI
a. o. a. 01
•N. V. "N. "O
O> Ol O> "X
a a a •»
a
1 ! 1 1
o o o o
^
o
c fa
O u
4^ VI
* v»
.a a>
1 3 -0
i_ c c
0.4- 4-
ac ac
i—
kn co 4-
E rt «» k.
<9 a tn ^ a
^— •^ ^~ ^C E
0) 31— 4?
|5 .e 2
e j= ea o —
»— o en ^
< «C
4-1 t— >— CO
c
Ol O Ol
VI •»- VI
4» <0 Ol
0> 3 01
ee E ee
f~ tfl -0 OB
i~- eo c en
>^ CD fmf
CO >t O •
c 2 3 r "S "i
1 - 5"~ jl 3
E oT <-> "Z 4-
4-1— ro — ' O O
CO Z C9 4) X M
C
•" r £ u
O3Cj=i_4-Eu- O
C OJ JZ — «J C •! O C 4JAJ
UC4-IQ UE ^— «— 34)
ooi 4-<3 o»»in'3M > 4^*«cc
U 3 •< »J 3 OCtj3>1 >- VIU4-OI
"nOJ3«5g "flB^C^"*^ *vi '^^"j'S
e:wv, O4W o vt.»LO
Olvi •- •» O) >*- -- JC -- O. 41 41
4-ouio 4- IQIIVI >> ooi-o
««-o2co ^o-viw IS .-'uvi
O Oi-COII O4-WIQ4J 4) — 41 >i rfl
Z Q.-fl,E— Q.*-r,av, 3« «T3UB
4> * (^ 4>| 4>
0> 0>
fco co i/i ac
II * +1 Z
X
u *—
VI if*
v> ««
4> •! E 0
•o E -* NI **
N. < E en
mt 01 *N, am
a a at i
-3. co o
O O "S <—
o o a en x
CSJ CO u^ F >A
II 1 l£ •
O O O r- i—
01
t-
o 0) e 4-1
4-1 l_ 4- -0 •—
ra e 3 o> a
U O 4.J •o •o u
4-4- r— Ol -0
vi vi a >
e a oi — x o
•*- VI U "O O 4J
ac ac oc
z z z
VI
Ol
01 9»
>- "wo
CD E VI J=
f- >» L.
-J <0 3 SI u i— 4J
LA U VI 4-
(OOttviO OI»C>
wi o vi *— i^ ct-g
•C«CO4)W J=>34-
1— h- 6 U h- UOJ=-»
O O
C C O O
o •a o 4—4-
T3 CD
c en
CO
O - CO
11 2
"Z 4^ 3."
0 O i—
XX Z
O C.J
z z
4-^ - 4.
< «£
"O *X
"o> I*
a> o
E co
a *
a o
cv o
o <•
u-> 0
19 c e
<— O •»• 4- c
O — i- O-—
vi w o E a. 4^ "o
_ ai e
•a « sn • 4- 4-. t_
4i -g E u
Oi * tZ o
c c L.
fcO 01 v» *
•V. Vl^ 01 01
U8S 15
14- «•-
O 0
c e
o a
3 3
co e u
— CO 1—40
0125d
-49-
09/01/89
-------
o>
£J
01
14-
0)
ae
c
i
u
01
Vt
i
a.
i/i
a>
ae
en
|f
-M k.
c
o
u
e
o
•*"
w
o.
CL
^
£
3
a.
x^
0 5
W ifl
«°
J^
l/t
«
in ir>
GO CD
i— CO i—
x co •*- »
J "« ""- 1 "5 •£
•— a. o c
Irt 10
OO CO
en en
«- CO
• <4~ * o a.
3** 1— O -vJ O •«-" Q *J h-
01 Z 31 4> 3
f
o
S
S g i 8. ".
"X, CO Q. Q. O
CR O
» o o *
a E o o
o o a. o o -
r~ * ex c»
a
f • O 1.
1 O O C
o o o
^ CM CO C
m
0>
ai c e
t- O *-
"s S --— e at c
U O.4-* O -^ Wl «
n u o
•— t- 4) C -O b. X
r~ ** -^» fc. Of W <
3 o
U •*- •- LI <^ I/I »
g
U CM
I O
> a o
re
e e
i 5 g 2'
5 '5 £ c
•Or- 1- O •—
: a> o> m o»— «-
• M "VI O.-W O
o u L. 01 X U 01 C
13 C • CCO
. WI «- 0 ^^0
oe ae r— ai r- o> ae
1-^3 1—3
en O> Cti A
M
Ol r-
L. U f—
01 «-.OI U
•w e w
e « - > a e
(04 U. O «3 •** •*
jc: i— <*i L. F— i/i c
V 6 a o
01 »» o e *
C W 01 t> I/I HJ -
•r- IQ *— C O •••• I
u o S A ea S <
c
*^ tfc- O
1 p—
w-
5^i
j e •* u
: ifi u O
0 0 —
j C l^
• a> I— r— U
al£ «
,
'*. !_•-«»
Or-Wl O'~««f_^ °'o>}5'(8-2
cSo ego "19 0)--6S>»
5°^ 5§Z OO 1
3OU 3Qt- — C
•01.01 -OL-ai u ™ i-iuie ae«' b
: — o c 3 a* i_ o
i a> *d *• *.. .Q >»**
< U -** *j U ^" >»
> U. 6 HH ^ — Q. «
41
1.
O
w
o
c
II
•»••
c
g
o
u
o
c
II
u
01
u
•^
TJ
O
II
z
i
0125d
-50-
09/01/89
-------
of gestation fetuses were removed, weighed and examined for viability,
external malformations, hlstologlcal parameters, skeleton abnormalities and
visceral changes. Bromoform had no effect on survival or fetal weight and
there was no evidence of a teratogenlc effect but there was evidence of a
fetotoxlc response. Although statistical analysis was not performed, It
appeared that there was an Increase 1n the number of Utters with sternebral
abberratlons at 100 and 200 mg/kg/day. No developmental effects were
observed at 50 mg/kg/day.
6.5. OTHER REPRODUCTIVE EFFECTS
Borzelleca (1983) reported that Intratestlcular administration of bromo-
form at a level of 100-1400 mg/kg to male CD-I mice resulted In Inhibition
of testlcular DNA synthesis.
6.6. SUMMARY
The liver, kidneys and central nervous system appear to be Important
target organs for bromoform toxlclty. Both Inhalation (Dykan, 1962, 1964)
and oral (NTP, 1988; Chu et al., 1982a,b; Borzelleca, 1983} administration
result In abberratlons In morphology or function of these organs. Hepato-
cellular vacuollzatlon was found In both male mice (>200 mg/kg/day) and male
rats (>50 mg/kg/day) 1n a subchronlc study (13 weeks, 5 days/week) and In
female mice (>100 mg/kg/day) In a chronic study (103 weeks, 5 days/week)
sponsored by NTP (1988). Compound-related mortality was observed In male
rats (200 mg/kg/day) 1n the chronic study. Also, narcosis (Sax, 1984) and
lethargy (Bowman et al., 1978; Chu et al., 1980; NTP, 1988) were observed In
animals receiving bromoform by Inhalation and oral routes, respectively.
Altered RES function was observed In male and female mice receiving bromo-
form at a level of 125 mg/kg/day for 90 days by gavage (Munson et al., 1977,
0125d -51- 09/01/89
-------
1978). Operant behavior was Impaired after administration of bromoform to
mice at levels of 100 and 400 mg/kg/day for 60 days (Balster and Borzelleca,
1982).
NTP (1988) concluded that there was "some evidence of carclnogenlclty of
bromoform for male F344/N rats and clear evidence...for female F344/N rats."
Female rats at 200 mg/kg/day displayed a higher Incidence of neoplastlc
lesions of the large Intestine compared with male rats and untreated
controls (NTP, 1988). This may be due In part to the fact that male rats
had reduced survival rates compared with females at equal doses (NTP, 1988).
Bromoform tested positive for mutagenlcHy In both in yjyo and in vitro
assays (NTP, 1988). Bromoform did not produce teratogenlc effects, but did
produce fetotoxlc effects In rats treated at 100, but not at 50 mg/kg/day
(Ruddlck et al., 1983).
Information exists on the effects of bromoform and other trlhalomethane
contamination In drinking water on humans; however, this Information Is
considered Incomplete and preliminary because there are several unaddressed
variables (NTP, 1988).
0125d
-52-
09/01/89
-------
7. EXISTING GUIDELINES AND STANDARDS
7.1. HUMAN
The recommended TLV for bromoform 1s 0.5 ppm {5 mg/m3), with a skin
designation, based on the chemical's Irritant qualities (AC6IH, 1986). OSHA
(1985) established a PEL of 0.5 ppm (5 mg/m3). U.S. EPA (1987b) reported
an RfD for bromoform of 2xlO~2 mg/kg/day based on the NOAEL for hepatic
lesions of 25 mg/kg/day In the subchronlc NTP (1988) study, and an Interim
maximum contaminant level for drinking water of 0.10 mg/l for total
trlhalomethanes. The latter value Is based on the chronic toxldty of
chloroform.
U.S. EPA (1982) derived an ambient water quality criterion of 0.19
mg/l for bromoform based on an uncertainty factor of 1000, an ADI of 0.39
mg/day (based on a study by Chu et al., 1982a), a dally water and contaml-'
nated fish consumption of 2 I/day and 0.0065 kg/day, respectively, and a
BCF of 7.0 I/kg.
Based on chronic toxldty, the RQ value for release Into the environment
1s 100 pounds {U.S. EPA, 1987b, 1988).
7.2. AQUATIC
Guidelines and standards for the protection of aquatic life from
exposure to bromoform were not located 1n the available literature cited In
Appendix A.
0125d -53- 09/01/89
-------
8. RISK ASSESSMENT
8.1. CARCINOGENICITY
8.1.1. Inhalation. Pertinent data regarding the Inhalation carclnogen-
Iclty of bromoform 1n humans or animals were not located 1n the available
literature dted 1n Appendix A.
8.1.2. Oral. NTP (1988) sponsored a gavage study with 50 male and 50
female F344/N rats and 50 male and 50 female B6C3F1 mice. Neoplastlc
lesions (adenomatous polyps or adenocarclnomas) attributed to bromoform were
found In the large Intestines of three male rats receiving bromoform 5
days/week for 2 years at a level of 200 mg/kg/day, one female rat receiving
100 mg/kg/day and eight female rats receiving 200 mg/kg/day. There were no
lesions of this type In the vehicle control group.
Krayblll (1983) lists bromoform as a suspected human carcinogen In'
drinking water. According to Cantor et al. (1978), there 1s a positive
correlation between levels of trlhalomethanes In drinking water and the
Incidence of several human cancers.
8.1.3. Other Routes. Thelss et al. (1977) reported an Increase (p<0.04)
1n the number of pulmonary adenomas In strain A mice following 23
IntraperHoneal Injections of the test substance 1n Trlcaprylln at a level
of 48 mg/kg/1nject1on. There was no significant difference In the number of
lung tumors 1n mice administered bromoform at a level of 4 mg/kg/lnjectlon
for 18 Injections or 100 mg/kg/1nject1on for ?4 Injections.
8.1.4. Height of Evidence. Although studies pertaining to human cancer
risk and drinking water contamination exist, these studies group many
halomethanes together and fall to consider circumstances such as exposure to
other potential carcinogens, family history and lifestyle. The human data
may be best considered "Inadequate." The evidence for cardnogenlclty In
0125d
-54-
09/01/89
-------
animals Is sufficient because studies In two species (rats and mice) demon-
strated an Increase In cancer Incidence after oral or 1ntraper1toneal admin-
istration of bromoform. Therefore, according to the U.S. EPA (1986) guide-
lines for carcinogenic risk assessment, bromoform should be assigned to EPA
Group B2, a probable human carcinogen. This assessment Is supported by
positive results 1n mutagenlclty tests and by the carclnogenlclty of
structurally related compounds.
8.1.5. Quantitative Risk Assessment.
8.1.5.1. INHALATION — Appropriate Inhalation exposure data were not
located from which to estimate the carcinogenic potency for Inhalation
exposure to bromoform. A q^ of 7.9xlQ~3 (mg/kg/day)'1 was estimated
for humans orally exposed to bromoform based on an Increased Incidence of
neoplasms of the large Intestine In female rats treated by gavage (Section'
8.1.5.2.). Several factors suggest that the tumorlgenlc response observed
In the large Intestine may be a systemic rather than a portal-of-entry
effect. The mutagenlclty data (see Section 6.3.) Indicate that metabolism
with mammalian S-9 1s necessary for a genotoxlc response 1n microorganisms
and mammalian cell cultures. Pharmacoklnetlc data suggest that gastro-
intestinal absorption Is rapid (see Section 5.1.) and that blotransformatlon
Is an activating mechanism (see Section 5.3.). Conversely, while the liver
has been shown to metabolize bromoform by way of dlbromocarbonyl, some of
the evidence Indicates that liver metabolites may not be completely
responsible for tumor Induction. While a much greater fraction of bromoform
was metabolized by mice, only rats showed significant carcinogenic
response. Furthermore, the tumor site was In the gastrointestinal tract, an
early site of contact. Nothing In the pharmacoklnetlc studies rules out
bromoform or an active Intermediate metabolized by the Intestinal cells as
an ultimate carcinogen.
0125d -55- 09/01/89
-------
When possible, the best approach to route-to-route extrapolation for
estimating cancer potency for chemicals requiring metabolic activation Is to
base the estimation on a metabolized dose rather than an exposed or Internal
dose. Kinetic data for the metabolism of bromoform are Insufficient,
however, to estimate route-specific metabolized doses. It Is possible that
lesser metabolism would occur following Inhalation exposure because of the
absence of the "first pass" phenomenon. If so, the estimate of Inhalation
cancer potency based on the oral study may be unnecessarily stringent and
guidelines derived therefrom may be overly protective. In the NTP (1988)
study, bromoform was given 1n corn oil. If the bromoform was absorbed with
the corn oil Into the lymphatics, bypassing the hepatic portal system, It Is
possible that the metabolism of bromoform In this study may approximate that
expected from Inhalation exposure.
On the other hand, the metabolic studies were based upon a bolus dose of
bromoform. The rats In those studies metabolized a much smaller fraction of
the compound than mice and exhaled 1t through the lungs much more rapidly.
This Indicates that metabolism of bromoform Is fairly slow and that. In rats
at least, most of It Is exhaled before It could be metabolized to an active
form. When given by Inhalation, however, bromoform will remain In the body
as long as exposure continues. This allows many passes through the liver
and assures that a greater percentage of the compound will be activated.
For this reason, 1t seems likely that the potency by Inhalation would be
underestimated using oral exposure data. Because of the uncertainties
associated with the metabolism and the mechanism of bromoform activity In
tumor Induction, estimation of a q,* for Inhalation exposure by
extrapolation from oral data 1s not recommended.
0125d
-56-
09/01/89
-------
8.1.5.2. ORAL — The cancer risk assessment for exposure to bromoform
Is based on an oral exposure study (NTP, 1988) 1n which an Increased
Incidence of neoplasms was observed In the large Intestine of treated female
rats (see Table 6-2). Derivation of a cancer potency estimate (q-,*) Is
presented In Appendix B. The equivalent human dosages estimated In Appendix
B are derived from the transformed animal doses multiplied by the cube root
of the ratio of the estimated group mean animal body weight to the assumed
human body weight (70 kg), then further multiplied by the cube of the ratio
of length of exposure (103 weeks) to the assumed llfespan of the animal (104
weeks) (U.S. EPA, 1980b). The q * generated by the Howe and Crump (1982)
multistage model based on equivalent human dosages 1s 7.9xlO~3 (mg/kg/
day)-!, which 1s an estimate of excess cancer risk to exposed humans. The
pharmacoklnetlc data Indicate that gastrointestinal absorption 1n rats 1s'
>78.9%. In the absence of more definitive data, It 1s assumed that
gastrointestinal absorption Is 100%. Therefore, this q * of 7.9xlO~3
(mg/kg/day)"1 for oral exposure 1s considered to be the cancer potency
based on Internal dose. The concentrations of the chemical 1n drinking
water associated with an Increased lifetime risk of cancer of 10~5, 10~e
and 10~7 are 4.4xlO~2, 4.4xlO~3 and 4.4xlO"4 mg/l respectively.
These values were derived by dividing the corresponding risk levels by the
q * correcting for the assumed human body weight of 70 kg and the assumed
dally Intake of water of 2 l.
8.2. SYSTEMIC TOXICITY
8.2.1. Inhalation Exposure.
8.2.1.1. LESS THAN LIFETIME EXPOSURES — Dykan (1962) briefly
reported disorders 1n the glycogenesls and protein prothromblm functions of
the liver and filtration capacity of the kidneys of rats exposed to bromo-
form at a level of 250 mg/m3, 4 hours/day for 2 months. This Inhalation
0125d -57- 09/01/89
-------
exposure expanded over a 24-hour period and a 7-day week corresponds to a
dosage of 26.5 mg/kg/day. Because of Inadequate reporting of this study, a
subchronlc Inhalation RfD cannot be derived.
8.2.1.2. CHRONIC EXPOSURES — Dykan (1964) briefly reported that the
threshhold concentration for chronic exposure to bromoform was 50 mg/m3
for rats. He also stated that humans occupied with bromoform production
exhibited changes In the central nervous system and liver. The experimental
protocol was not reported and an Inhalation dosage cannot be derived from
these data.
8.2.2. Oral Exposure.
8.2.2.1. LESS THAN LIFETIME EXPOSURES — Subchronlc oral exposure
studies exist for male and female rats and male and female mice. In a study
sponsored by NTP (1988), lethargy was present In male rats administered'
bromoform by gavage for 13 weeks at dose levels >100 mg/kg and In female
rats given 200 mg/kg. All of the male rats given 200 mg/kg had diarrhea.
Hepatocellular vacuollzatlon was present at a level greater than that of the
vehicle control group In male rats at all doses >12 mg/kg. The vacuoles
were more numerous In the liver cells of high-dose rats, however, and
statistical significance was present at levels >50 mg/kg for 5 days/week
(35.7 mg/kg/day). No significant effects were observed at levels <25 mg/kg
for 5 days/week (17.9 mg/kg/day). NTP (1988) also reported dose-related
cytoplasmlc vacuollzatlon of hepatocytes In male mice receiving 200 or 400
mg/kg/day for 13 weeks.
Chu et al. (1982b) reported a slight Increase In relative kidney weights
In male Sprague-Dawley rats administered bromoform 1n drinking water at a
level of 500 ppm, but not at 50 ppm, for 28 days.
0125d
-58-
09/01/89
-------
Munson et al. (1977) reported a decrease In blood clearance of
I125-labeled L.. monocytogenes 1n male mice receiving bromoform at a level
of 0.2 mg/kg/day for 90 days by oral gavage. A dose-related depression In
specific activity of L.. monocytogenes In the liver was observed In females
and males receiving bromoform at a level of 125 mg/kg/day (Munson et al.,
1977, 1978). The decrease 1n blood clearance and specific activity In the
liver Indicated a reduced uptake and disposal of phagocytlc cells. Munson
et al. (1977) concluded that there was a slight alteration In RES function.
Operant behavior was Impaired 1n male ICR mice administered bromoform by
gavage at a level of 100 and 400 mg/kg/day for 60 days (Balster and
Borzelleca, 1982).
Chu et al. (1982a) reported significantly decreased lymphocyte counts In
male and female Sprague-Dawley rats exposed to bromoform In drinking water
at a level of 2500 ppm for 90 days with a 90-day recovery period.
Suppressed food consumption was observed 1n male rats exposed to 2500 ppm.
M1ld hlstologlcal changes In the liver and thyroid were observed In both
male and female rats at all dose levels between 5 and 2500 ppm, but were
more severe and occurred at a higher frequency at levels >500 ppm. These
effects were not apparent after the 90-day recovery period.
No effects were observed 1n male CD-I mice administered bromoform 1n
drinking water up to a level of 250 mg/kg/day for 90 days (Borzelleca,
1983). Also, Schuller et al. (1978) reported no effects on hypersensHlv-
Hy, humoral Immune response, liver function, kidney function or hematology
In male and female ICR mice administered bromoform by gavage at a dose up to
125 mg/kg/day for 90 days.
The study most suitable for an RfO determination Is the 13-week study
sponsored by NTP (1988). This study provides the highest NOAEL below which
there 1s no LOAEL. From the NTP (1988) study, the NOAEL for male rats (the
0125d -59- 09/01/89
-------
most sensitive subjects In this study) was 25 mg/kg, 5 days/week for 13
weeks (17.9 mg/kg/day). Statistically significant hepatocellular vacuollza-
tlon was not present at this level but was present at levels >50 mg/kg for 5
days/week (35.7 mg/kg/day). Chu et al. (1982a) also reported liver effects
at levels >500 ppm (70 mg/kg) for 90 days. The subchronlc oral RfO 1s 0.179
mg/kg/day (17.9 mg/kg/day divided by an uncertainty factor of 100; 10 for
Interspecles extrapolation multiplied by 10 to provide additional protection
for more sensitive Individuals). The subchronlc oral RfD Is most appro-
priately rounded to 0.2 mg/kg/day, or 13 mg/day for a 70 kg human. Medium
confidence Is placed In this RfD. NTP (1988) used both sexes of two animal
species and both species had the liver lesions used to derive the NOAEL.
8.2.2.2. CHRONIC EXPOSURE — Ruddlck et al. (1983) administered
bromoform (96% pure) dissolved 1n corn oil by gavage to groups of 15 mated
Sprague-Dawley rats at a level of 0 (vehicle control), 50. 100 or 200
mg/kg/day from day 6-15 of gestation. The Agency considers this to be
chronic exposure to fetuses. Extensive clinical and hlstopathologlcal
examinations revealed no evidence of teratogenesls but there was evidence of
fetotoxldty. Although no statistical analysis was reported, 1t appeared
that there was an Increase In the number of Utters with sternebral abberra-
tlons at 100 and 200 mg/kg/day. The NOAEL for developmental effects was 50
mg/kg/day.
In a chronic gavage study sponsored by NTP (1988), 50 male and 50 female
rats and 50 female mice were administered bromoform at levels of 0, 100 or
200 mg/kg, and 50 male mice were administered the test substance at levels
of 0, 50 or 100 mg/kg, 5 days/week for 103 weeks. Compound-related deaths
were observed 1n male rats receiving 200 mg/kg/day; lethargy was observed In
treated male and female rats; aggressiveness was observed 1n treated male
rats; and decreased mean body weights were observed 1n high-dose males and
0125d
-60-
09/01/89
-------
females. Nonneoplastlc lesions were observed In dosed rats of both sexes;
Increased mixed cell fod, decreased basophlllc foci and decreased necrosis
of the liver were observed In dosed females (compared with controls); and
liver lesions and Increased gastric ulcers and chronic Inflammation of the
lung were observed In dosed males.
Mean body weights of dosed female mice were decreased, folUcular cell
hyperplasla of the thyroid gland was observed In dosed females, cytoplasmlc
vacuollzatlon of hepatocytes was observed In high-dose females and hyper-
plasla of the glandular stomach was observed In dosed males.
The LOAEL In this study 1s 50 mg/kg/day for 5 days/week (35.7 mg/kg/
day). Hyperplasla of the glandular stomach was observed In male mice at
this level. Since no lower dose levels were evaluated, a NOAEL does not
exist. The subchronlc data provide a NOAEL of 17.9 'mg/kg/day that Is'
supported by the chronic data. The subchronlc oral RfD of 0.2 mg/kg/day can
serve as the basis for the RfD for chronic oral exposure by application of
an additional factor of 10 to expand from subchronlc to chronic exposure.
Therefore, the RfD for oral exposure 1s 0.02 mg/kg/day. Moderate confidence
1s placed In this RfO because of the lack of a threshhold level for chronic
exposure. The verified oral RfD presented In IRIS (U.S. EPA, 1987b) 1s also
2xlO~2. This RfD was also derived from subchronlc data before chronic
data were available; an uncertainty factor of 1000 was applied.
8.3. AQUATIC
Insufficient data prevented the development of criteria for the protec-
tion of freshwater (Figure 8-1) and marine (Figure 8-2) life exposed to
bromoform. Development of a freshwater criterion requires the results of
acute assays with a salmonld fish species, a benthlc crustacean, a
non-Arthropod/Chordate, and a new Insect or phylum representative. Results
from chronic assays required for the development of a freshwater criterion
0125d -61- 09/01/89
-------
Fami ly
«1
Chordate (Salmonid-f ish)
#£
Chordate (warrnwater fish)
#3
Chordate (fish or amphibian)
#4
Crustacean (planktonic)
#5
Crustacean (benthic)
#6
Insect an
#7
non-Arthropod/-Chordate
#8
New Insect an or phylum
represent at i ve
*9
algae
ttlG
Vascular plant
TEST TYPE
Acute-
Nfl
£9*
5£«
45. £«
NO (
75-
NA
NO
Nft
Nft
Chronic*
Nfi
Nfl
NO
Nft
NP
NO
Nfl
Nfl
114'
Nfl
BCF-
Nfl
Nfl
Nfl
Nft
Nfl
NA
Nfl
Nfl
Nfl
Nfl
aNA = Not available; b96-hour LCso 1n mg/4 with blueglll sunflsh.
j-gporcls macrochlrus: cLCso In mg/l for carp embryos, CypMnus carplo;
"48-hour LCso 1n ppm for Daphnla magna and 96-hour LCso In mg/t for
ulex; 624-hour LCjo . 1n ppm for larval mosquitoes, Aedes
.
aegypU: r96-hour £€50 1n ppm for Selanastrum caprlcornutum
FIGURE 8-1
Organization chart for listing FMAVs required to derive numerical water
quality criteria by the method of EPA/OWRS (1986) for the protection of
freshwater aquatic life exposed to bromoform
0125d
-62-
09/01/89
-------
Farn i I y
*i
Chordate
#£
Chordate
*3
non- Arthropod /-Chordate
#4
Crustacean (Mysid/Panaeid)
*5
riori-Chordate
#6
nori-Chordate
*7
non— Chordate
«a
other
#9
algae
ttlO
Vascular plant
TEST TYPE
Acute*
1£»
11.3-
NA
£4.4-
>4C>»
> Vo»
>4O
£6'
NA
NA
Chronic*
NA
6. 39«
NA
NA
NA
NA
NA
NA
11. 9J
NA
ECF*
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
aNA = Not available; b96-hour LCso In mg/i for menhaden, Brevoortla
tyranus; C96-hour LC50 1n mg/i for sheepshead minnow, Cypr1n1don
varleqatus; dHATC In mg/i for sheepshead minnow, C. varlegatus;
e96-hour LCso In ppm for Mysldopsls bahla: f96-hour LCso In mg/l
for the clam, HercenaMa mercenarla: n96-hour LCso ln m9/'4 for the
oyster, Crassostrea v1rg1n1ca~; ^96-hour LCso 1n "jg/l • for the shrimp,
aztecus: J96-hour ECso In ppm for Skeletonema costatum
FIGURE 8-2
Organization chart for listing FMAVs required to derive numerical water
quality criteria by the method of EPA/OWRS (1986) for the protection
of saltwater aquatic life from exposure to bromoform
0125d
-63-
09/01/89
-------
Include assays with two species of fauna and at least one bloconcentratlon
study. Development of a saltwater criterion requires the results of an
acute assay with a non-Arthropod/Chordate species. Results from chronic
assays required for the development of a saltwater criterion Include an
assay with one species of fauna and at least one bloconcentratlon study.
0125d
-64-
09/01/89
-------
9. REPORTA8LE QUANTITIES
9.1. BASED ON SYSTEHIC TOXICITY
The effects of oral and Inhalation exposure to bromoform were discussed
1n Chapter 6. Dose-response data for lexicologically significant effects In
studies of sufficient quality and duration suitable for RQ derivation are
summarized In Table 9-1. As noted 1n Table 9-1, oral administration of
bromoform to animals has resulted In liver lesions, lethargy, diarrhea,
Impaired operant behavior, changes In hematology, low body weight, feto-
toxlclty and Increased mortality.
Several possible CSs and corresponding RQs are derived In Table 9-2. In
computing the chronic human MED from the human equivalent dose 1n the
subchronlc studies, no uncertainty factor was applied to expand to chronic
exposure, because the NTP (1988) studies suggest little difference In toxic'
potency between subchronlc and chronic exposure. CSs were not estimated for
diarrhea (NTP, 1988), which was considered to be an acute manifestation of
gavage dosing, nor for reduced lymphocyte count (Chu et al., 1982a), which
occurred only during the recovery period and Is of uncertain toxlcologlc
significance. A CS for lethargy was calculated for males In the subchronlc
NTP (1988) study and not for females 1n the chronic NTP (1988) study because
the males In the subchronlc study had lower body weights, which would result
In the higher RV.. A CS for liver lesions was calculated from the NTP
(1988) subchronlc study, but not from the Chu et al. (1982a) study because
the lower human equivalent dose was estimated from the NTP (1988) study.
The most severe effect Is reduced survival In the NTP (1988) chronic
study. This corresponds to an RV of 10. A chemical-related Increase In
mortality was observed 1n male rats administered bromoform at a level of 200
mg/kg/day, 5 days/week for 103 weeks, which corresponds to an equivalent
0125d -65- 09/01/89
-------
E
&»
o
I
m
o
>»
**
u
X
o
u
c
ft
tl
ft
ae
ft
VI
c
o
QL
!£
ae
£VI
o
> e
11
LLJ Z
•o o, —
ft vi >»
ESS
£-*
ll|
-«-
u
a
v*
O
Q.
>.
•**
a.
1
Jjjf
»
ft
2 -5* "Si's?
ft O — It
* *
ft «*
B "> «5
s -^
M V>
X
(A
^
VI B
U L.
§Lv>
> IV ft N ft >» 0)
CO 0) U *• VI U »-
i- £ Or— mo
Si. "-• O fll £ t.
k. <« 3 1.0. ft
*^ iv ow u we >
ft *- Oi IV - « >• —
-
o r^ LO oo o
r- r^ iX O^ OJ
r— C\J tfl «—
*-* r> ui o "e
VI VI V) I.
*flu o»4»u- o
0* 4) CM O* C* 4) * tt* a> dm-
^^« ^^« <5« I& a&
'£J2 ^F2 li-2 of ^s
O T7 W o *O L. T9C. O O
o o o 2 o o *->o oo
« « » g
•^ — •- o
tu
B B e f- w
o o o eg
u v w uj 2
* 4 * u
in *
CM CM fM CO
o o o o
o o o o
1- fZ 1- CM
X K K u.
1
xx= x5 x? xlST
VI * VI * V» *• VI IQ ^
<«n
f^
•o
o
1
o
(^
*
"
VI
J<
en"! S
0) i^ ^3
g »,-
I'l
at
kO
o
e
o
u
|
o
o
to
*
X?
VI *
1« CO
L. U.
01
9
IO
>
3
i
*
a.
en
1
n
pj
^J
"
VI
JK
^ ft
« «, ft
on w 31
X XP>
g1 J,®
g3|
S
"o
e
o
u
A
m
CM
o
O
vn
Lk
CO
00
a.
^^
«^
k.
§
T3
VI
o
e
u
1
o
e
i/i
"•
o
CO
?
JMC *
<^ ^»
OC ft
»»
^
M
O
^
4.
0
^!
o
»
>•
D>kA B
^ ^* O
1*5
s
en
"S
e
g
jQ
O
in
^
"•
t
xlt
V* IV *^
"S Q. *
t-WO
S.
IV
>
S
£
fmm
•
e *
o *•*•
li
ji
\
Z2
VI
•o o
2U
si
•o o.
*
o
in
^
11
<*
$0
LO l_
CM O
SI
SI
1
o
PI
CM
*
OB
u.
"
oe
£
^
8
S.
3
OT25d
-66-
09/01/89
-------
o
u
01
u
c
01
t
(•>
£
4)
%rt
g
^^
VI
b
gg
— •
ft v> >>
ES3
0 <
1^ ^~ 0)
*•> S -x
e a -v.
Ill
Ol
1^
3
4/1
a
M
it*
>»
«.•
i
&
«
(•"•
u
1
& ~
>« »i£ —
ilST
>»ft_
i-t
1«5
X *A
K
&
S5
^ ^~
— >
ii
— a
r-
o
e
>,
IR
2-5
BIO
fi<«
§fe
V U.
S
4.
e
x-
CX !••
ii
tu *
ft
p>
e
o
«?
iA
K
Of
u
>!
»
o
e
»
o>
J
ei
o
f~
•«
£
Ol
i
>»
•a
e
A
e
^
£
«rf
O
««
*^
x:
0>
i
>*
5
i
c
•D
ft
£
4fe
e
o
«*
O
<*•>
O
o
L.
2
a
u
>»
£ -2
+* 4M
M
3K^
A Of
«» £
V*
A •»
€ 5
« "0
ft ^^
1 €
4k C -"•*
1*8
tw o«
i f s1
e * -
"O" k •
e v>
* :
£ w S
•• ft •»
>
01 k *>
B a £
^ u J
^~ ^ "'
£ 1 !
1 ,° J
* I *
i : :
•~ ft u
ie *• e
= i £
U — ft
r^ «< «h»
IB M ft
if Jtf ff
<4C
I
>>
1
•fl
^
Of
o
e
0)
k
Ol
•
£
?
«
^
•D
1
•O
>1
"e
^^
«*
ffl
*
a
o
M
u
s
L.
01
«fc.
Of
!•>
1
>»
^
•2
O
**
e
*•
>.
^.
+*
if
S-2
Is
iCuj
3^
5^
3"
1
«
<
&
Mrf
*v>
9
^^
$
»>
C i
**"! ««
i °
! r
u
e ••-'
S -
t •
? SI
0125d
-67-
09/01/89
-------
e
0
u_
ca
U.
0
<4-
l «/»
w» w
... Q
-J U
co co
1— O)
_J
I/I
o
e"
"
o
O)
w
c
(U
U
d>
*4—
Q^
oe
o-
OX
0
o>
OS
*•»
^
<4_
LU
•o
oe
«
O <•••>
O LU >.
c "O
ocx.
»
ea 5
^^
^^ ^yj
11
X.
vi C
t> —
*«• fQ
^J (••
0) •*•
ex co
CO
CO 00
CO 00
on on
r~ <—
» •
o. a.
r— (—
Z 2
O 0
§ §
1— r—
•*
00 00
r- O
3 «-
r— •«->
^MM ^
>l V N
u o I—
^ *^ o
.e us 3
•<-> ex u
Qf A) i^
r— £ >
CM v£>
o tn
r- CD
f~ CO
^- r—
* •
r- Ift
2 Z
•N^ V. V. X.
4^ *^ ^* ^^
(Q CO IQ CO
at u_ oeu.
CO
CO
on
r^
•
Q.
r-
z
0
o
o
un
*•
*
o>
i
>%
o
X
o
^
^
o
r-
CT>
^
*
r—
2
*«^ *^
W ^&
*** ^&
10 CO
oe u_
CO
CO
en
00 r-
CO
O^ Jt£ *
^— w •
•f* »^"
* ^3 *O
a. -a
h™* 3 ^^
Z 02 0
0 O
0 0
0 O
a eo
O 00
Z?
•0 9n U
w «- x
i"0 i"™* CJ
Of 13 -f
U ** O
U 1- ->-•
§4^
<*—
F— ^
tr> o
r- CO
r- en
5 o
,
0)
Z 3 >>
^^ ^v ^v O^ O
& ^& w ^1 ^^
** * •*- t. 3
ae u_ ae co ^
•
^
IQ
CO
•*-" r-
0; on
l1^
c
o •
vi r*~
c r-
*•} ^^
Xr-
O
O
0
00
r-
vC
U
a
VI
•0 O
01 *-
4Q O
Of O
i- at
U TJ
•0 Q.
CO
CO
wn
u
£
CM
CO
cn
*~
•o •
CO u
(_ ^—
4) r-
4^ 4^
Vi N
^ 1—
^3 ^5
00 CO
o
o
0
r—
00
en
r—
c
fO
§•
•o t-
a, o
w -^
TJ <«
tf
a
*
CO
CM
un
§
ae
0
i— i
V
0)
u
£
.^
^
o>
"to
^
^^
•Q
o
—
3
J=
0)
U
O)
3)
3 J*
U
i— O
^ r^
«_» >—
4
0125d
-68-
09/01/89
-------
human dose of 24.5 mg/kg/day. Multiplied by the assumed human body weight
of 70 kg, this becomes a MED of 1715 mg/day, which corresponds to an RV.
of 1. Multiplying the RVg of 10 by the RVd of 1 results 1n a CS of 10,
which corresponds to an RQ of 1000 pounds (Table 9-3).
Other studies summarized In Table 9-2 resulted In lower CSs. Lethargy
and low body weight were also reported In the NTP (1988) chronic study with
rats. This occurred at a lower dose (higher RV.) but was assigned a lower
RV . Lethargy and hepatocellular vacuollzatlon were also observed In rats
1n the subchronlc NTP (1988) study. Although 1t occurred at the lowest
dose, hepatocellular vacuollzatlon was considered a relatively nonsevere
effect. Likewise, the decreased hepatic phagocytosis observed In mice
(Munson et al., 1977, 1978) was assigned a lower RV . Impaired operant
behavior In mice observed by Balster and Borzelleca (1982) was also'
evaluated as a less severe effect. The fetotoxldty 1n rats described by
Ruddlck et al. (1983) was a severe effect but resulted In a lower CS than
the chronic NTP (1988) study.
U.S. EPA (1983) reported possible RQs of 100 or 1000 pounds. These RQs
were derived from the decrease 1n hepatic phagocytosis at levels of 12.5 or
125 mg/kg/day, respectively, reported In the 90-day subchronlc study by
Munson et al. (1978). Also, the transformed animal doses of 12.5 and 125
mg/kg/day were divided by a factor of 10 to convert to a chronic value. The
actual minimum effective dose Is difficult to discern from these abstracts.
Also, the toxlcologlcal significance of reduced hepatic phagocytosis 1s
unclear. These data will not be used In quantitative risk assessment
primarily because more comprehensive subchronlc and chronic toxlclty studies
are available.
0125d -69- 09/01/89
-------
TABLE 9-3
Bromoform
Minimum Effective Dose (MED) and Reportaole Quantity (RQ)
Route:
Dose*:
Effect:
Reference:
RVd:
RVe:
Composite Score:
RQ:
gavage
1715 mg/day
mortality
NTP, 1988
1
10
10
1000 pounds
'"Equivalent human dose
0125d
-70-
09/01/89
-------
The current accepted RQ should be re-evaluated In light of the new data
available from NTP (1988).
9.2. BASED ON CARCINOGENICITY
NTP (1988) evaluated the carclnogenlclty of bromoform administered by
gavage to male and female rats and female mice at levels of 0 (vehicle
control), 100 or 200 lug/kg/day and to male mice at levels of 0, 50 or 100
mg/kg/day, 5 days/week for 103 weeks (see Section 6.2. and Table 6-2).
Adenomatous polyps or adenocarclnomas were observed In the large Intestines
of three male rats receiving 200 mg/kg/day, one female receiving 100 mg/kg/
day and eight females receiving 200 mg/kg/day. No tumors were observed In
mice. Bromoform Increased the number of pulmonary adenomas/mouse 1n the
strain A assay at 48 mg/kg, but not at 100 mg/kg (Thelss et al., 1977). The
compound was administered by Intraperltoneal Injection thrice weekly for 23
total Injections. The evidence for cardnogenlclty In animals Is considered
sufficient together with positive evidence In short-term tests, mutagen1c1ty
and structure-activity relationship with other B2 carcinogens such as
CHC13 and CHBrCl-. The evidence pertaining to human data Is
Inadequate. Bromoform Is assigned to EPA Group B2 (see Section 8.1.).
The potency factor (F factor) calculated using the Incidences of
neoplastlc lesions 1n the female rats (NTP, 1988) and the computerized
multistage model developed by Howe and Crump (1982) 1s 5.86294x10~2
(mg/kg/day)"1 (Table 9-4). Because the F factor 1s <1, bromoform 1s
placed In Potency Group 3. A Potency Group 3 chemical with an EPA classi-
fication of B2 corresponds to a LOW hazard rank under the CERCLA Hazard
Ranking Scheme. Chemicals with a LOU hazard ranking are assigned an RQ of
100.
0125d -71- 10/25/89
-------
TABLE 9-4
Derivation of Potency Factor (F) for Bromoform
Reference:
Exposure route:
Species:
Strain:
Sex:
Vehicle or physical state:
Body yelght:
Duration of treatment:
Duration of study:
Llfespan of animal:
Target organ:
Tumor type:
Experimental doses/exposures:
Equivalent human doses (mg/kg/day):
Tumor Incidence:
Human 1/EO^rj (F Factor):
NTP, 1988
gavage
rats
F344/N
F
corn oil
-0.250 kg*
103 weeks
103 weeks
104 weeks
large Intestine
adenomatous polyps and adenocarclnomas
0 (vehicle control), 100 or 200
mg/kg/day, 5 days/week
0, 10.6, 20.5
0/50, 1/50, 8/50
0.058624 (mg/kg/day)'1
'Estimated from graphs
0125d
-72-
09/01/89
-------
10. REFERENCES
Abdul, A.S., T.L. Gibson and D.N. Ral. 1987. Statistical correlations for
predicting the partition coefficient for nonpolar organic contaminants
between aquifer organic carbon and water. Haz. Waste Haz. Materials. 4:
211-222.
ACGIH {American Conference of Governmental Industrial Hyglenlsts). 1986.
Documentation of the TLV and Biological Exposure Indices, 5th ed.
Cincinnati, OH. p. 67.
Agarwal, A.K. and H.M. Mehendale. 1983. Absence of potentlatlon of bromo-
form hepatotoxldty and lethality by chlordecone. Toxkol. Lett. 15(2-3):'
251-257.
Ahmed, A.E., V.L. Kublc and M.W. Anders. 1977. Metabolism of haloforms to
carbon monoxide: I. In vitro studies. Drug Metab. Dlspos. 5(2): 198-204.
Ahmed, A.E., V.L. Kublc, J.L. Stevens and M.W. Anders. 1980. Halogenated
methanes: Metabolism and toxlclty. Fed. Proc. 39(13): 3150-3155.
Albano, E., A. Tomasl, K.H. Cheeseman, V. Vannlnl and M.U. Olanzanl. 1985.
Use of Isolated hepatocytes for the detection of free radical Intermediates
of halogenated hydrocarbons. Free Radicals Liver Inj., Proc. Int. Meet.,
1st. p. 7-16.
0125d -73- 09/01/89
-------
Amoore, J.E. and E. Hautala. 1983. Odor as an aid to chemical safety: Odor
thresholds compared with threshold limit values and volatilities for 214
Industrial chemicals In air and water dilution. J. Appl. Toxlcol. 3:
272-290.
Anders, M.W., J.L. Stevens, R.W. Sprague, Z. Shaath and A.E. Ahmed. 1978.
Metabolism of haloforms to carbon monoxide. II. In vivo studies. Drug
Metab. Dlspos. 6(5): 556-560.
Anderson, D.R., R.M. Bean, C.I. Gibson and P.R. Reed. 1979. Bloclde
By-Products In Aquatic Environments. Quarterly Progress Report, January 1 -
March 31, 1979. Govt. Rep. Announce, and Ind. 26: 45.
Atkinson, R. 1987. A structure-activity relationship for the estimation of
rate constants for the gas-phase reactions of OH radicals with organic
compounds. Int. J. Chem. Kinetics. 19: 799-828.
Balster, R.L. and J.F. Borzelleca. 1982. Behavioral toxldty of trlhalo-
methane contaminants of drinking water In mice. Environ. Health Perspect.
46: 127-136.
Balster, R.L., J. Burkhalter and J. Borzelleca. 1979. Behavioral toxldty
evaluation of 4 halomethane contaminants of drinking water In adult mice.
Fed. Proc. 38(3 part 1): 846.
Beech, J.A., R. 01az, C. Ordaz and B. Palomeque. 1980. Nitrates, chlorates
and trlhalomethanes In swimming pool water. Am. 3. Public Health. 70:
79-82.
0125d
-74-
09/01/89
-------
Berg, W.W., L.E. Heldt, W. Pollock, P.O. Sperry, R.J. Cicerone and E.S.
Gladney. 1984. Bromlnated organic species In the Arctic atmosphere.
Geophys. Res. Lett. 11: 429-432.
Borzelleca, J.F. 1983. A review of volatile organic contaminant data.
Proc. AWWA Water Qual. Technol. Conf. p. 225-244.
Bouwer, E.J. and P.L McCarty. 1983. Transformations of halogenated organic
compounds under dlnltrlfIcatlon conditions. Appl. Environ. Hlcroblol. 45:
1295-1299.
Bouwer, E.J. and P.L. McCarty. 1984. Modeling of trace organlcs blotrans-
formatlon In the subsurface. Groundwater. 22: 433-440.
Bouwer, E.J., P.L. McCarty, H. Bouwer and R.C. R1ce. 1984. Organic con-
taminant behavior during rapid Infiltration of secondary wastewater at the
Phoenix 23rd Avenue project. Water Res. 18: 463-472.
Bowman, F., J.F. Borzelleca and A.E. Munson. 1978. The toxlclty of some
halomethanes 1n mice. Toxkol. Appl. Pharmacol. 44(1): 213-215.
Brodzlnsky, R. and H.B. Singh. 1982. Volatile organic chemicals In the
atmosphere: An assessment of available data. Atmospheric Science Center.
SRI International, Menlo Park, CA., Contract 68-02-3452. p. 150.
Buccafusco, R.J., S.J. Ells and G.A. LeBlanc. 1981. Acute toxlclty of
priority pollutants to blueglll (Lepomls macrochlrus). Bull. Environ.
Contain. Toxlcol. 26(4): 446-452.
0125d -75- 09/01/89
-------
Bur-master, D.E. 1982. The new pollutlon-groundwater contamination.
Environ. 24: 6-13, 33-36.
Buther, H., P. Rlcklefs, H. Teutsch and W. Thlemann. 1986. Gluthathlone
does not enhance the overall rate of metabolism of halogenated methanes.
Chemosphere. 15(8): 1043-1062.
Callahan, M.A., H.W. SUmak, N.W. Gabel, et al. 1979. Water-related
environmental fate of 129 priority pollutants. Vol. 11. EPA-440/4-79-029B.
U.S. EPA, Washington, DC. p. 61-1 to 61-6.
Cantor, K.P., R. Hoover, T.J. Mason and L.J. McCabe. 1978. Associates of
cancer mortality with halomethanes In drinking water. J. Natl. Cancer Inst.'
61{4): 979-985.
Chu, I,, V. Secours, I. Marino and D.C. Vllleneuve. 1980. The acute
toxlclty of four trlhalomethanes In male and female rats. Toxlcol. Appl.
Pharmacol. 52(2): 351-353.
Chu, I.. D.C. Vnieneuve, V.E. Secours, G.C. Becking and V.E. ValH. 1982a.
Trlhalomethanes: II. Reversibility of toxlcologlcal changes produced by
chloroform, bromodlchloromethane. 3. Environ. Sc1. Health. 17(3): 225-240.
Chu, I., O.C. Vllleneuve, V.E. Secours, G.C. Becking and V.E. Valll. 1982b.
Toxlclty of trlhalomethanes: I. The acute and subacute toxldty of chloro-
form, bromodlchloromethane, chlorodlbromomethane and bromoform 1n rats. J.
Environ. ScK Health. 17(3): 205-224.
0125d
-76-
09/01/89
-------
Class, T., R. Kohnle and K. Ballschmlter. 1986. Chemistry of organic
traces In air. VII. Bromo and bromochloromethanes In air over the Atlantic
Ocean. Chemosphere. 15: 429-436,
Condle, L.W., C.L. Smallwood and R.D. Laurie. 1983. Comparative renal and
hepatotoxldty of halomethanes: Bromodlchloromethane, bromoform, chloroform,
dlbromochloromethane and methylene chloride. Drug Chem. Toxlcol. 6(6):
563-578.
Dewalle, F.B. and S.K. Chlan. 1978. Presence of trace organlcs 1n the
Delaware River and their discharge by municipal and Industrial sources.
Proc. Ind. Waste Conf. 32: 903-919.
Dykan, V.A. 1962. Changes In liver and kidney functions due to methylene
bromide and bromoform. Nauchn. Tr. Ukr. Nauchn. - Issled. Inst. Glgleny
Truda 1 Profzaboleuan11. 29: 82-90. (CA 60:8561d)
Dykan, V.A. 1964. Problems on toxicology, clinical practice and work
hygiene In the production of bromine-organic compounds. Gig. Sb. 100-103.
(CA 63:15429g)
Dyksen, J,E. and A.F. Hess, III. 1982. Alternatives for controlling
organlcs In ground water supplies. J. Am. Water Works Assoc. 74: 394-403.
Elsenrelch, S.J., B.J. Looney and J.D. Thornton. 1981. Airborne organic
contaminants 1n the Great Lakes ecosystem. Environ. Scl. Techno!. 15:
30-38.
0125d -77- 09/01/89
-------
Ellis, D.D., C.M. Jone, R.A. Larson and Q.J. Schaeffer. 1982. Organic
constituents of mutagenlc secondary effluents from wastewater treatment
plants. Arch. Environ. Contam. Toxlcol. 11: 373-382.
EPA/OWRS (Environmental Protection Agency/Office of Water Regulations and
Standards). 1985. Guidelines for deriving numerical national water quality
criteria for the protection of aquatic organisms and their uses. U.S. EPA,
Washington, DC. 106 p.
Erlckson, S.J. and C.E. Hawkins. 1980. Effects of halogenated organic
compounds on photosynthesis In estuarlne phytoplankton. Bull. Environ.
Contam. Toxlcol. 24(6): 910-915.
Fodor, G.G. and A. Roscovanu. 1976. Increased blood-carbon monoxide-
content In humans and animals by Incorporated halogenated hydrocarbons.
Zentralbl., BakteMol., Parasltenkd., Infektlonskr. Hyg. Abt. 1: Orlg.,
Relhe B. 162(1-2): 34-40.
Fraga, C.G., B.E. Lelbovltz and A.L. Tappel. 1987. Halogenated compounds
as Inducers of llpld peroxldatlon In tissue slices. Free Radlc. B1ol. Med.
3(2): 119-123.
Francois, C., R. Mestres and C. Causse. 1979. Study of the evaporation of
some haloform mlcropollutants from water. Trav. Soc. Pharm. MontpelHer.
39: 49-58.
0125d
-78-
09/01/89
-------
Furlong, E.A.N. and P.M. DHrl. 1986. Tr 1 halomethane levels In chlorinated
Michigan drinking water. Ecol. Model. 32: 215-225,
Galloway, S.M., A.D. Bloom, M. Resnlck, et al. 1985. Development of a
standard protocol for jn. vitro cytogenetk testing with Chinese hamster
ovary cells: comparison of results for 22 compounds In two laboratories.
Environ. Mutagen. 7: 1-51.
Gibson, C.I., F.C. Tone, P. Wilkinson and J.W. Blaylock. 1979a. Toxlclty
.and effects of bromoform on five marine species. Unpublished report.
Gibson, C.I., F.C. Tone, P. Wilkinson and J.W. Blaylock. 1979b. Toxlclty
and effects of bromoform on five marine species. Unpublished report.
Gibson, C.I., F.C. Tone, R.E. Schlrmer and J.W. Blaylock. 1979c. Bloaccu-
mulatlon and depuration of bromoform In five marine species. Unpublished
report. 22 p.
Gibson, C.I., F.C. Tone, P. Wilkinson, J.W. Blaylock and R.E. Schlrmer.
1981. Toxlclty, bloaccumulatlon and depuration of bromoform 1n five marine
species: Protothaca stamlneae. llttleneck clam, Mercenarla mercenaMa.
Eastern hard clam, quahog, Crassostrea vlrglnlca. Eastern oyster, Penaeus
aztecus. brown shrimp, Brevoortla tyrannus. Atlantic menhaden. Gov. Rep.
Announce. 81(1): 2178.
Gschwend, P.M., 3.K. Macfarlane and K.A. Newman. 198S. Volatile halo-
genated organic compounds released to seawater from temperate marine
macroalgae. Science. 227: 1033-1035.
0125d -79- 09/01/89
-------
Hannah, S.A., B.M. Austern, A.E. Eralp and R.H. Wise. 1986. Comparative
removal of toxic pollutants by six wastewater treatment processes. J. Mater
Pollut. Control. Fed. 58: 27-34.
Hawley, G.G. 1981. The Condensed Chemical Dictionary, 10th ed. Van
Nostrand Relnhold Co., New York. p. 151-152.
Heltmuller P.T., T.A. Holllster and P.R. Parrlsh. 1981. Acute toxlclty of
54 Industrial chemicals to sheepshead minnows Cyprlnodon varlegatus. Bull.
Environ. Contain. Toxlcol. 27(5): 596-604.
Helz, G.R. 1980. Anthropogenic Cl and C2 halocarbons: Potential applica-
tion as coastal water-mass tracers. In.: Hydrocarbon Halo. Hydrocarbon'
Aquatic Environ., B.K. Afghan and D. Mackay, Ed. Plenum Press, NY.
p. 435-444.
H1ne, J. and P.K. Mookerjee. 1975. The Intrinsic hydrophlUc character of
organic compounds. Correlations In terms of structural contributions. 3.
Org. Chem. 40: 292-298.
Hopkins, R.M. and J.C. Krantz, Jr. 1968. Anesthesia. LXXV. Relative
effects of haloforms and eplnephrlne on cardiac automatlclty. Anes. Anal.
47(1): 56-67.
Horvath, A.L. 1982. Halogenated Hydrocarbons. SolubllHy-HlsclbllHy with
Water. Marcel Dekker, Inc., New York, NY. p. 480.
0125d
-80-
09/01/89
-------
Howe, R.B. and K.S. Crump. 1982. Global 82. A computer program to
extrapolate quanta! animal toxlclty data to low doses. Prepared for Office
of Carcinogen Standards, OSHA, U.S. Dept. of Labor.
Hutzler, N.J., J.C. CMttenden and J.S. Glerke. 1986. Transport of organic
compounds with saturated groundwater flow: Experimental results. Water
Resources Res. 22: 285-295.
Kaiser, K.L.E., M.E. Ccmba and H. Huneault. 1983. Volatile halocarbon
contaminants In the Niagara River and In Lake Ontario. J. Great Lakes Res.
9: 212-213.
Kelley, R.D. 1985. Synthetic organic compounds sampling survey of public'
water supplies. NTIS PB85-214427. p. 1-32.
Kerster, H.W. and D.J. Schaeffer. 1983. Brine shrimp (Artemla sallna)
nauplH as a teratogen test system. Ecotoxlcol. Environ. Saf. 7(3):
342-349.
Kllngensmlth, J.S. and H.M. Mehendale. 1981. Potentlatlon of bromlnated
halomethane hepatotoxlclty by chlordecone In the male rat. Toxlcol. Appl.
Pharmacol. 61(3): 378-384.
Koyama, Y. and Y. Nakazawa. 1986. Comparison of the effect of trlhalo-
methanes on llpld metabolism In rat liver slice. Toxlcol. Lett. 31(1):
37-44.
0125d -81- 09/01/89
-------
Krayblll, H.F. 1980. Evaluation of public health aspects of carcinogenic
mutagenlc blorefractorles In drinking water. Conference of the primary
prevention of cancer: Assessment of risk factors and future directions, New
York, NY. Prev. Hed. 9(2): 212-218.
Krayblll, H.F. 1983. Assessment of human exposure and health risk environ-
mental contaminants In the atmosphere and water with special reference to
cancer. 3. Environ. Scl. Health Part C. 1(2): 175-232.
Kroneld, R. 1987. Effect of volatile halocarbons on lymphocytes and cells
of the urinary tract. Bull. Environ. Contam. Toxlcol. 38: 856-861.
Kurokawa, Y. 1987. Personal communication from Y. Kurokawa, National'
Institute of Hygienic Sciences, Tokyo, Japan to R. Melnlck, National
Toxicology Program, North Carolina. (Cited 1n NTP, 1988)
LeBlanc, G.A. 1980. Acute toxldty of priority pollutants to water flea.
Bull. Environ. Contam. Toxlcol. 24(5): 684-691.
Leuze, E. 1922. No title provided. Arch. Expts. Path. Pharmakol. 95:
145. (Cited In ACGIH, 1986}
Lucas, G.H.W. 1928. A study of the fate and toxlcHy of bromine and
chlorine containing anesthetics. J. Pharmacol. 34: 223-237.
Lyman, H.J. 1982. Adsorption coefficients for soils and sediments. In.:
Handbook of Chemical Property Estimation Methods, W.J. Lyman, H.F. Reehl and
D.H. Rosenblatt, Ed. McGraw H111 Book Co., New York. p. 4-9.
0125d
-82-
09/01/89
-------
Lyman, W.J., W.F. Reehl and D.H. Rosenblatt. 1982. Handbook of Chemical
Property Estimation Methods. Environmental Behavior of Organic Compounds.
McGraw-Hill Book Co., New York, NY. p. 5-5.
Mabey, W. and T. Mill. 1978. Critical review of hydrolysis of organic
compounds In water under environmental conditions. 0. Phys. Chem. Ref.
Data. 7: 383-392.
Maddock, M.8. and J.J. Kelly. 1980. A sister chromatld exchange assay for
detecting genetic damage to marine fish exposed to mutagens and carcinogens.
Hater Chlorlnatlon: Environ. Impact Health Eff. 3: 835-844.
Mattlce, J.S., S.C. Tsal, M.B. Burch and J.J. Beauchamp. 1981. Toxlclty of'
trlhalomethanes to common carp (Cyprlnus carplo) embryos. Trans. Am. Fish.
Soc. 110(2): 261-269.
Merzbach, L. 1928. No title provided. Zeltschr. Ges. Exptel. Med. 63:
383. (Cited 1n ACGIH, 1986)
Mink, F.L., T.J. Brown and J. Rlckabaugh. 1986. Absorption, distribution
and excretion of 14C-trlha1omethanes In mice and rats. Bull. Environ.
Contam. Toxlcol. 37(5): 752-758.
Mochlda, K. and M. Yamasakl. 1984. Toxlclty of halomethanes to cultured
human and monkey cells. Bull. Environ. Contam. Toxlcol. 33(3): 253-256.
0125d -83- 09/01/89
-------
Moody, O.A. and E.A. Smuckler. 1986. Disturbances In hepatic heme metabo-
lism 1n rats administered alkyl halldes. Toxlcol. Lett. 32(3): 209-214.
Moody, D.E., J.L. James, G.A. Glawson and E.A. Smuckler. 1981. Correlation
among the changes In hepatic mlcrosomal components after Intoxication with
alkyl halldes and other hepatotoxlns. Mol. Pharmacol. 20(3): 685-693.
Horlmoto, K. and A. Koizumi. 1983. Trlhalomethanes Induce sister chromatld
exchanges In human lymphocytes ^n_ vitro and mouse bone marrow cells In vivo.
Environ. Res. 32(1): 72-79.
Munson, A.E., V.M. Sanders, B.A. Barrett and 3.F. Borzelleca. 1977. Func-
tional activity of the RES In mice exposed to haloalkanes for 90 days. Res.'
J. Retlculoendothel. Soc. 22: 17a.
Munson, A.E., V.M. Sanders, J.F. Borzelleca, R.G. Tardlff and B.A. Barrett.
1978. Retlculoendothellal system function In mice exposed to four halo-
alkanes. Toxlcol. Appl. Pharmacol. 45(1): 329-330. (Cited 1n U.S. EPA,
1983)
Munson, A.E., I.E. Sain, V.M. Sanders, B.M. Kauffmann and K.L. White, Jr.
1982. Toxicology of organic drinking water contaminants: Trlchloromethane,
bromodlchloromethane, dlbromochloromethane and trlbromomethane. Environ.
Health Perspect. 46: 117-126.
0125d
-84-
09/01/89
-------
Nlshimura, H., T. Otake, M. Kataoka, et al. 1980. Safety evaluation of
organic compounds In drinking water. 3. Effects of trlhalomethanes on rats.
Osaka-furHsu Koshu Elsel Kenkyusho Hokoku, Koshu Elsel Hen. 18: 95-103.
{CA 096/1373013)
NTP (National Toxicology Program). 1988. Technical Report on the Toxicology
and Carclnogenesls Studies of TMhalomethene (Bromoform) (CAS No. 75-25-2)
In F344 In rats and B6C3F) Mice (Gavage Studies). Board Draft.
OSHA (Occupational Safety and Health Administration). 1976, General
Industry standards. OSHA 2206, revised January, 1976. U.S. Dept. Labor,
Washington, DC. (Cited In U.S. EPA, 1980a)
OSHA (Occupational Safety and Health Administration). 1985. Permissible
Exposure Limits. 20 CFR 1910.1000. p. 655-659.
Otson, R. 1987. Purgeable organlcs In Great Lakes raw and treated water.
Int. J. Environ. Anal. Chem. 31: 41-53.
Otson, R., O.T. Williams and P.O. Bothwell. 1982. Volatile organic
compounds at thirty Canadian potable water treatment facilities. J. Assoc.
Anal. Chem. 65: 1370-1374.
Page, G.W. 1981. Comparison of groundwater and surface water for patterns
and levels of contamination by toxic substances. Environ. Sc1. Technol.
15: 1475-1481.
0125d -85- 09/01/89
-------
Pankow, J.F., L.M. Isabelle and W.E. Asher. 1984. Trace organic compounds
In rain. I. Sampler design and analysis by adsorption/thermal desorptlon.
(AID). Environ. Sc1. Techno!. 18: 310-318.
Parra, P., E. Martinez, C. Sunol, et al. 1986. Analysis, accumulation and
central effects of trlhalomethanes. 1. Bromoform. Toxlcol. Environ. Chem.
11(2): 79-91.
Perelra, M.A. 1983. Carclnogenlclty of cltlorlnatlon byproducts trlhalo-
methanes. Water Chlorlnatlon: Environmental Impact and Health Effects, Vol.
4, Part 2. Proc. 4th Conf. Environment, Health and Risk. Ann Arbor Science
Publishers, Ann Arbor, HI. p. 1165-1176.
Perelra, H.A., S.L. Herren, A.L. Brltt and M.M. Khoury. 1982a. Initiation
promotion bloassay 1n rat liver: Use of gamma glutamyltranspeptldase-
posltlve fod to Indicate carcinogenic activity. Toxlcol. Pathol. 10:
11-18.
Perelra, H.A., L-H.C. L1n, J.M. Llppltt and S.L. Herren. 1982b. Trlhalo-
methanes as Initiators and promoters of carclnogenesls. Environ. Health
Perspect. 46: 151-156.
Perwak, J., H. Goyer, 0. Harris et al. 1980. An exposure and risk assess-
ment for trlhalomethanes (chloroform, bromoform, bromodlchloromethane,
dlbromochloromethane). Arthur D. Little, Inc., Cambridge, HA. p. 42-47.
EPA-440/4-81/01B. NTIS PB85-211977/WIP.
Ol25d
-86-
09/01/89
-------
Pohl, L.R., J.L. Martin, J.W. George and R.J. Hlghet. 1980a. A mechanism
for the depletion of liver glutathlone by trlhalomethanes and tetrahalo-
methanes. Meeting of the American Society for Pharmacology and Experimental
Therapeutics, Rochester, MN, USA, Aug. 17-21. Pharmacologist. 22(3): 228.
Pohl, L.R., J.L, Martin, A.M. Taburet and J.W. George. 1980b. Oxldatlve
bloactlvatlon of haloforms Into hepatotoxlns. In: MUrosomes, Drug Ox1d.
Chem. Carclnog., Int. Symp. Mlcrosomes, Drug Oxld. 4th 1979. 2: 881-884.
Poyer, 3.L., P. Downs and W.H. Masslon. 1986. Free-radical formation
during U) vitro and hi vivo metabolism of trlbromomethane. Fed. Proc.
45(4): 1051.
Raddlng, S.B., D.H. L1u, H.L. Johnson and T. Mill. 1977. Review of
environmental fate of selected chemicals. U.S. EPA, Washington, DC.
EPA-560/5-77-003. p. 69-72.
Rao, P.S.C., A.G. Hornsby and R.E. Jessup. 1985. Indices for ranking the
potential for pesticide contamination of groundwater. Soil. Crop. Sc1. Soc.
Fl. Proc. 44: 1-8.
Reynolds, E.S. 1972. Comparison of early Injury to liver endoplasmlc
retlculum by halomethanes, hexachloroethane, benzene, toluene, bromobenzene,
ethlonlne, thloacetamlde and dimethyllnltrosamlne. Blochem. Pharmacol.
21(19): 2555-2561.
0125d -87- 09/01/89
-------
Richie, J.P., Jr., B.O. Mills and C.A. Lang. 1984. The verification of a
mammalian toxicant classification using a mosquito screening method. Fund.
Appl. Toxlcol. 4(6): 1029-1035.
Rlttmann, B.E., P.L. McCarty and P.V. Roberts. 1980. Trace-organlcs
blodegradatlon In aquifer recharge. Groundwater. 18: 236-243.
Roberts, P.V., J. Schrelner and G.D. Hopkins. 1982. Field study of organic
water quality changes during groundwater recharge 1n the Palo Alto baylands.
Water Res. 16: 1025-1035.
Ruddlck, J.A., D.C. Vllleneuve, I. Chu and V.E. ValH. 1983. A terato-
loglcal assessment of four trlhalomethanes In the rat. J. Environ. Sc1.
Health. 18(3): 333-349.
Sax, N.I., Ed. 1984. Dangerous Properties of Industrial Materials, 6th ed.
Van Nostrand Relnhold Co., NY. p. 529-530.
Schuller, G.B., B.M. Kaufman, J.F. Borzelleca, V.M. Sanders and A.E. Munson.
1978. Effect of 4 haloalkanes on humoral and cell mediated Immunity in
mice. Toxlcol. Appl. Pharmacol. 45(1): 329.
Scott, G.I., D.P. Mlddaugh, A.M. Crane, N.H. McGlothlln and N. Watabe.
1980. Physiological effects of chlorine-produced oxldants and uptake of
chlorlnatlon by-products In the American oyster, Crassostrea vlrglnlca.
Water Chlorlnatlon: Environ. Impact Health Eff. 3: 501-516.
0125d
-88-
09/01/89
-------
Scott, G.I., T.I. Samnons, D.P. Hlddaugh and M.J. Hemmer. 1982. Impacts of
water chlorlnatlon and conform bacteria on the American oyster, Crassostrea
vlrglnka. Physlol. Mech. Mar. Pollut. Toxic. (Proc. Symp. Pollut. Har.
Org.) 505-529.
Scott, G.I., O.P. Mlddaugh and S. Kllngensmlth. 1983. Bloconcentratlon of
bromoform by American oysters Crassostrea vlrglnlca exposed to chlorinated
and dechlorlnated sea water with notes on survival and feeding. R.L. Jolley
et al.. Ed. Water Chlorlnatlon: Environ. Impact and Health Effects. 4(2):
1029-1038.
Shlklya, 0., G. Tsou, J. Kowalskl and F. Leh. 1984. Ambient monitoring of
selected halogenated hydrocarbons and benzene In the California South Coast'
Air Basin. Proc. APCA 77th Annu. Meet. Vol. 1. p. 2-21.
Simmon, V.F. 1977a. Mutagenlc activity of chemicals Identified In drinking
water. In: Progress In Genetic Toxicology Proceedings of 2nd International
Conference on Environmental Mutagens, Edlnburg, July 11-15, 1977.
p. 249-258.
Simmon, V.F. 1977b. Structural correlation of carcinogenic and mutagenlc
ally! halldes. In.: Structural Correlates of Cardnogenesls and Mutagenesls.
Proc. Second FOA Office of Sc1. Summer Symp., I.M. Asher and C. Zerbos, Ed.
FDA Office of Science, USA. p. 163-171.
Simmon, V.F. 1981. Applications of the Salmonella/mlcrosome assay.
Short-term Tests. Chem. Carclnog. p. 120-126.
0125d -89- 09/01/89
-------
Simmon, V.F. and R.G. Tardlff. 1978. Mutagenlc activity of halogenated
compounds found 1n chlorinated drinking water. Water Chlorlnatlon: Environ.
Impact Health Eff. Proc. Conf. 2: 417-431.
SRI (Stanford Research Institute). 1987. 1987 Directory of Chemical
Producers: United States of America. SRI International, Menlo Park, CA.
p. 495.
Stenger, V.A. 1978. Bromine compounds. In; Klrk-Qthmer Encyclopedia of
Chemical Technology, 3rd ed., Vol 5, M. Grayson and D. Eckroth, Ed. John
Wiley and Sons", Inc., NY. p. 253.
Stevens, J.L. and M.W. Anders. 1979. Metabolism of haloforms to carbon'
monoxide. III. Studies on the mechanism of the reaction. Blochem.
Pharmacol. p. 3189-3194.
Stevens, J.L. and M.W. Anders. 1981. Metabolism of haloforms to carbon
monoxide. IV. Studies on the reaction mechanism in vivo. Chem. Blol.
Interact. 37(3): 365-374.
Stewart, M.E., W.J. Blogoslawskl, R.Y. Hsu and G.R. Helz. 1979.
By-products of oxldatlve blocldes: Toxlclty to oyster larvae. Mar. Pollut.
Bull. 10(6): 166-169.
Suffet, I.H., L. Brenner and P.R. Cairo. 1980. Gas chromatography-mass
spectrometry Identification of trace organlcs In Philadelphia, Pennsylvania,
USA drinking waters during a two year period. Water Res. 14: 853-867.
0125d
-90-
09/01/89
-------
Swann, R.L., D.A. Lasowskl, P.J. HcCall, K. Vander Kuy and H.J. Dlshburger.
1983. A rapid method for the estimation of environmental parameter octanol/
water partition coefficient, soil sorptlon constant, water to air ratio and
water solubility. Res. Rev. 85: 17-28.
Symons, J.M., T.A. Bellar, J.K. Carswell, et al. 1975. National Organlcs
Reconnaissance Survey for halogenated organlcs. J. Am. Water Works Assoc.
67: 634-647.
Tabak, H.H., S.A. Quave, C.I. Mashnl and E.F. Barth. 1981. Biodegradable
Hy studies with organic priority pollutant compounds. J. Water Pollut.
Control Fed. 53: 1503-1518.
«
Tardlff, R.G., G.P. Carlson and V. Simmon. 1978. Halogenated organlcs 1n
tap water a toxicologlcal evaluation. R.I. Jolley, Ed. Water Chlorlnatlon.
Environmental Impact and Health Effects, Vol. 1. Proceedings of the
Conference on the Environmental Impact of Water Chlorlnatlon. Oak Ridge,
TN, USA, Oct. 22-24. p. 195-209.
Thelss, O.C., G.D. Stoner, M.B. Sh1mk1n and E.K. Welsburger. 1977. Test
for carclnogenldty of organic contaminants of United States drinking waters
by pulmonary tumor response In strain A mice. Cancer.Res. 37(8): 2717-2720.
Thomas,. R.G. 1982. Volatilization from water, in.: Handbook of Chemical
Property Estimation Methods. W.J., Lyman, W.F. Reehl and D.H. Rosenblatt,
Ed. HcGraw H111 Book Co., New York. p. 15-17 to 15-28.
0125d -91- 09/01/89
-------
Tomasl, A., E. Albano, F. Blasl, T.F. Slater, V. Vannlnl and M.U. Dlanzanl.
1985. Activation of chloroform and related trlhalomethanes to free radical
Intermediates In Isolated hepatocytes and In the rat in vivo as detected by
the ESR-spIn trapping technique. Chem. B1ol. Interact. 44(3): 303-316.
Torkelson, T.R. and V.K. Rowe. 1981. Halogenated aliphatic hydrocarbons.
In: Toxicology, Vol. 2B, Patty's Industrial Hygiene and Toxicology, 3rd ed,,
G.O. Clayton and F.E. Clayton, Ed. 3ohn Wiley and Sons, Inc., New York.
p. 3433-3601.
Trabalka, J.R. and H.B. Burch. 1978. Investigation of the effects of halo-
genated organic compounds produced 1n cooling systems and process effluents
on aquatic organisms. R.L. Jolley, H. Gorchev and D.R. Hamilton, 3r., Ed.'
Water Chlorlnatlon: Environ. Impact and Health Effects, p. 163-173.
Trabalka, J.R., S.C. Tsa1, J.S. Mattlce and H.B. Burch. 1979. Effects on
carp embryos (Cyprlnus carp1o) and Daphnla pulex of chlorinated organic
compounds produced during control of fouling organisms. Report (Conf-
7910138-3): 16 p.
U.S. EPA. 1977. Computer print-out of non-confidential production data
from TSCA Inventory. U.S. EPA, Office of Toxic Substances, Washington, DC.
U.S. EPA. 1978. In-depth studies on health and environmental Impacts of
selected water pollutants. Prepared by E.G. and G. Bionomics, Wareham, HA.
Contract #68-01-4646.
0125d
-92-
09/01/89
-------
U.S. EPA. 1980a. Ambient Water Quality Criteria Document for Halomethanes.
Prepared by the Office of Health and Environmental Assessment, Environmental
Criteria and Assessment Office, Cincinnati, OH for the Office of Mater Regu-
lations and Standards, Washington, DC. EPA-440/5-80-051. NTIS PB81-117624.
U.S. EPA. 1980b. Guidelines and Methodology Used in the Preparation of
Health Effect Assessment Chapters of the Consent Decree Water Criteria
Documents. Federal Register. 45(231): 79347-79357.
U.S. EPA. 1982. Errata: Halomethanes. Ambient Water Quality Criteria for
the Protection of Human Health. Prepared by the Office of Health and
Environmental Assessment, Environmental Criteria and Assessment Office,
*
Cincinnati, OH for Office of Water Regulations and Standards, Washington,
DC. p. 1-44.
U.S. EPA. 1983. Reportable Quantity Document for Trlbromomethane
(Bromoform). Prepared by the Office of Health and Environmental Assessment,
Environmental Criteria and Assessment Office, Cincinnati, OH for the Office
of Solid Waste and Emergency Response, Washington, DC. p. 1-5.
U.S. EPA. 1984. Methodology and Guidelines for Ranking Chemicals Based on
Chronic Toxlclty Data. Prepared by the Office of Health and Environmental
Assessment, Environmental Criteria and Assessment Office, Cincinnati, OH for
the Office of Emergency and Remedial Response. Washington, DC.
0125d -93- 09/01/89
-------
U.S. EPA. 1986. Guidelines for Carcinogen Risk Assessment. Federal
Register. 51(185): 33992-34003.
U.S. EPA. 1987a. Graphical Exposure Modeling System (GEMS). Personal
computer version. CLOGP computer program. April 1987. U.S. EPA, Research
Triangle Park, NC.
U.S. EPA. 1987b. Integrated Risk Information System (IRIS). Reference
Dose (RfD) for Oral Exposure for Bromoform. Online. (Revised; Verification
date 08/13/87). Office of Health and Environmental Assessment, Environ-
mental Criteria and Assessment Office, Cincinnati, OH.
U.S. EPA. 1988. STORET Water Quality Data Base. Online: May 1988.
van de Meent, D., H.A. Denhollander, VI.G. Pool, et al. 1986. Organic
Mlcropollutants In Dutch Coastal Waters. Water Sd. Techno!. 18: 73-81.
Veenstra, 3.N. and J.L. Schnoor. 1980. Seasonal variations 1n trlhalo-
methane levels In an Iowa River Water supply. Am. Water Works Assoc. J.
72: 583-590.
Verschueren, K. 1983. Handbook of Environmental Data on Organic Chemicals,
2nd ed. Van Nostrand Relnhold Co., New York. p. 291-292.
0125d
-94-
09/01/89
-------
von Oettlngen, W.F. 1955. The halogenated aliphatic, oleflnlc, cyclic,
aromatic and aliphatic-aromatic hydrocarbons Including the halogenated
Insecticides, their toxlclty and potential dangers. The Halog. Hydro-
carbons, Toxlclty and Potential Dangers. PHS No. 414. U.S. Govt. Printing
Office. U.S. DHEW, Public Health Service, Washington, DC.
Ward, G.S., P.R. Parrlsh and R.A. R1gby. 1981. Early life stage toxlclty
j
tests with a saltwater fish: Effects of eight chemicals on survival growth
and development of sheepshead minnows (CyprInodon varlegatus). J. Toxlcol.
Environ. Health. 8(1-2): 225-240.
WestMck, J.J., J.W. Hello and R.F. Thomas. 1984. The groundwater supply
survey. J. Am. Water Works Assoc. 76: 52-59.
Williams, D.T., R. Otson, P.O. Bothwell, K.L. Murphy and J.L. Robertson.
1980. Trlhalomethane levels In Canadian drinking water. In: Hydrocarbon
Halo. Hydrocarbon Aquatic Environ., B.K. Afghan and D. Mackay. Ed. Plenum
Press, NY. p. 503-512.
Wolf, C.R., D. Mansuy, W. Nastalnczyk, G. Deutschmann and V. Ullrich. 1977.
The reduction of polyhalogenated methanes by liver mlcrosomal cytochrome,
P450. Mol. Pharmacol. 13(4): 698-705.
Woodruff, R.C., J.M. Mason, R. Valencia and S. Zlmmerlng. 1985. Chemical
mutagenesls testing 1n Drosophlla. V. Results of 53 coded compounds tested
for the National Toxicology Program. Environ. Mutagen. 7(5): 677-702.
0125d -95- 09/01/89
-------
Zoeteman, B.C.3., E. Degreef and F.J.J. Brlnkman. 1981. Persistency of
organic contaminants In groundwater, lessons from soil pollution Incidents
In the Netherlands. Sd. Total Environ. 21: 187-202.
0125d
-96-
09/01/89
-------
APPENDIX A
LITERATURE SEARCHED
This HEED 1s based on data Identified by computerized literature
searches of the following:
CHEMLINE
TSCATS
CASR online (U.S. EPA Chemical Activities Status Report)
TOXLINE
TOXLIT
TOXLIT 65
RTECS
OHM TADS
STORET
SRC Environmental Fate Data Bases
SANSS
AQUIRE
TSCAPP
NTIS
Federal Register
CAS ONLINE (Chemistry and Aquatic)
HSDB
These searches were conducted 1n May 1988, and the following secondary
sources were reviewed:
ACGIH (American Conference of Governmental Industrial Hyglenlsts).
1986. Documentation of the Threshold Limit Values and Biological
Exposure Indices, 5th ed. Cincinnati, OH.
ACGIH (American Conference of Governmental Industrial Hyglenlsts).
1987. TLVs: Threshold Limit Values for Chemical Substances In the
Work Environment adopted by ACGIH with Intended Changes for
1987-1988. Cincinnati, OH. 114 p.
Clayton, G.D. and F.E. Clayton, Ed. 1981. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 2A. John Wiley and
Sons. NY. 2878 p.
Clayton, G.D. and F.E. Clayton, Ed. 1981. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 28. John Wiley and
Sons, NY. p. 2879-3816.
Clayton, G.D. and F.E. Clayton, Ed. 1982. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 2C. John Wiley and
Sons, NY. p. 3817-5112.
0125d
-97-
09/01/89
-------
Grayson, M. and 0. Eckroth, Ed. 1978-1984. Klrk-Othmer Encyclo-
pedia of Chemical Technology, 3rd ed. John Wiley and Sons, NY. 23
Volumes.
Hamilton, A. and H.L. Hardy. 1974. Industrial Toxicology, 3rd ed.
Publishing Sciences Group, Inc., Littleton, MA. 575 p.
IARC (International Agency for Research on Cancer). IARC Mono-
graphs on the Evaluation of Carcinogenic Risk of Chemicals to
Humans. IARC, WHO, Lyons, France.
Jaber, H.M., W.R. Mabey, A.T. L1eu, T.W. Chou and H.L. Johnson.
1984. Data acquisition for environmental transport and fate
screening for compounds of Interest to the Office of Solid Waste.
EPA 600/6-84-010. NTIS PB84-243906. SRI International, Menlo
Park, CA.
NTP (National Toxicology Program). 1987. Toxicology Research and
Testing Program. Chemicals on Standard Protocol. Management
Status.
Ouellette, R.P. and J.A. King. 1977. Chemical Week Pesticide
Register. McGraw-Hill Book Co., NY.
Sax, I.N. 1984. Dangerous Properties of Industrial Materials, 6th
ed. Van Nostrand Relnhold Co., NY.
SRI (Stanford Research Institute). 1987. Directory of Chemical
Producers. Menlo Park, CA.
U.S. EPA. 1986. Report on Status Report In the Special Review
Program, Registration Standards Program and the Data Call In
Programs. Registration Standards and the Data Call 1n Programs.
Office of Pesticide Programs, Washington, DC.
USITC (U.S. International Trade Commission). 1986. Synthetic
Organic Chemicals. U.S. Production and Sales, 1985, USITC Publ.
1892, Washington, DC.
Verschueren, K. 1983. Handbook of Environmental Data on Organic
Chemicals, 2nd ed. Van Nostrand Relnhold Co., NY.
Wlndholz, M., Ed. 1983. The Merck Index, 10th ed. Merck and Co.,
Inc., Rahway, NJ.
Worthing, C.R. and S.B. Walker, Ed. 1983. The Pesticide Manual.
British Crop Protection Council. 695 p.
0125d
-98-
09/01/89
-------
In addition, approximately 30 compendia of aquatic toxldty data were
reviewed, Including the following:
Battelle's Columbus Laboratories. 1971. Water Quality Criteria
Data Book. Volume 3. Effects of Chemicals on Aquatic Life.
Selected Data from the Literature through 1968. Prepared for the
U.S. EPA under Contract No. 68-01-0007. Washington, DC.
Johnson, W.W. and M.T. Flnley. 1980. Handbook of Acute Toxlclty
of Chemicals to F1sh and Aquatic Invertebrates. Summaries of
Toxldty Tests Conducted at Columbia National Fisheries Research
Laboratory. 1965-1978. U.S. Dept. Interior, F1sh and Wildlife
Serv. Res. Publ. 137, Washington, DC.
McKee, J.E. and H.W. Wolf. 1963. Water Quality Criteria, 2nd ed.
Prepared for the Resources Agency of California, State Water
Quality Control Board. Publ. No. 3-A.
Plmental, 0. 1971. Ecological Effects of Pesticides on Non-Target
Species. Prepared for the U.S. EPA, Washington, DC. PB-269605.
Schneider, B.A. 1979. Toxicology Handbook. Mammalian and Aquatic
Data. Book 1: Toxicology Data. Office of Pesticide Programs, U.S.
EPA, Washington, DC. EPA 540/9-79-003. NTIS PB 80-196876.
0125d -99- 09/01/89
-------
APPENDIX B
Cancer Data Sheet for Derivation of q-j*
Compound:
Reference:
Species, Strain, Sex:
Body Height:
Length of exposure (le) ~
Length of experiment {Le)
Llfespan of animal (L) =
Tumor site and type:
Route, Vehicle:
Bromoform
NTP, 1988
Rat, F344/N, Female
estimated from graphs
103 weeks
103 weeks
104 weeks
large Intestine, adenomatous polyps or
adenocarclnomas .
gavage, corn oil
Experimental
Doses or
Exposures
(mg/kg/day.
5 days/week)
0
100
200
Body
Height
(kg)
0.250
0.250
0.225
Transformed
Dose
(mg/kg/day)
0
71.4
142.9
Equivalent
Human Dosage
(mg/kg/day)
0
10.6
20.5
Incidence
No. Responding/
No. Tested
(or Examined)
0/50
1/50
8/50
Human
= 7.9xlO'3 (mg/kg/day)'1
0125d
-100-
09/01/89
-------
e
o
**-
X 0
*"" ,£
i «.
CL 2
ft 1
3
i
Ol
Ol
Ol
01
oe
v
L.
0
O
oe
^t
u
Ol
1^
uu
0>
ki
9
e
o.
X
UJ
'
Ol
u
Ol
a.
GO
CO
•-
•
a o o >—
****** z
k.
s5
X.
QI^x
Q a a « rt o
i— * *M i— * o <~- r^
fc_
ifl e
*— o
^— *•*
01 XI
—• O
as
a o o 01 n)
l-H 1— 1 l-l & >
01
•x 5^
vt "O
'O 01
l«1
>l«l
X, r—
>J w
i"!
CM
to
_J
O O O O O
t '
01
3
I/I
0 >l
X «- i
>> k. 01 3
•S £ S tl
o»> u
y*x E o
E ailc
o m A
• • o a
o — r- i/.
a> T3
VI 3
A I/I
^
nj c o
i— 0 —
3 •- C
•— •" O
r— O 3
IQ 3 VI
a. u
4i 10 e
.c > e
01
•x 5"
VI 13
ra cr>x>
•a j< 3
**«-
- u
•o r~ o
X. f- L.
Jf kl
X, VI JO
P>^dE 3
E Ol v>
CM O
-J 0)
O O ID
Z <4- J3
.^
kl
"c
o
k.
u
CO
CO
•-
- .
^
z eg co
2 2
* *
a. a.
0) Z Z
VI
at
^ VI
• a
1 -i T3
a i
*>< ^*ia
en n c
- *O k.
r— x. 01
n j< e
^^ "^
4i 01
e7— o
k. .e
e -u
vi e
<— in «)
o g c
a. B •—
vi e vi
3 ^ 01
O k.
^ T3 fl
"5
vi 'a
* ^< x.
>> 01 O>
mi 01 n
•0 BX.
Ji O
11^
o »- .—
ai e
x, •
gw»-
>>r^
<— ID
* a
o ui —
o
S §
4^
b.
t^ •- u
LJJ X -r-
- 2 g
>-> o>
1— u O
>» 2 •- e
•^ = o TJ
kl O k. k.
C kW k> k>
01 —1
01 a e e
0 < e> o
"3 o « «i
k. O. VI VI
•a uj ra ra
u at a «
,
ra
•o
e
01
u
j£
i^
3
VI
c
u
o
t-H
0125d
-101-
07/08/91
-------
------- |