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ETHYLENE DIBROMIDE
CAS No.: 106-93-4
I. PHYSICAL AND CHEMICAL PROPERTIES SUMMARY (HSDB, 1998)
Molecular weight 187.88
Boiling Point
131-132° C
Melting Point
9.8° C
Vapor pressure
0.11 mm Hg at 20° C
Air concentration conversion 1 ppm = 7.81 mg/m 3
II.
HEALTH ASSESSMENT VALUES
Unit Risk Factor: 7.1 E-5 (µg/m 3 ) -1
Slope Factor: 2.5 E-1 (mg/kg-day) -1
[Male rat nasal tumor incidence (NTP, 1982), cancer risk range calculated using the Weibullmultistage
procedure CDHS (1985); unit risk “best value” selected by CDHS (1988) for
Proposition 65 purposes.]
III.
CARCINOGENIC EFFECTS
Human Studies
Quantitative and qualitative information on the carcinogenicity of ethylene dibromide (EDB) in humans is
limited. The epidemiological studies to date have either been suggestive but inconclusive or have lacked
the statistical power to detect an effect.
Carcinogenic effects were not observed in men exposed to EDB for four years or more at two
Associated Octel manufacturing facilities in the United Kingdom (Turner and Barry, 1979). Excess
cancers would not have been expected, however, given the duration and magnitude of exposure, the
carcinogenic potency of EDB in laboratory animals, the number of workers studied and the length of
time elapsing since first exposure.
Ott et al. (1980) reported on the cancer mortality among workers exposed while employed at EDB
manufacturing facilities in Texas and Michigan. Among workers at the Texas facility, there were no
statistically significant increases in cancer above those expected. Among workers at either facility with
more than six years of exposure, four died from malignant cancers, compared to an expected 1.6 deaths
from cancer (p = 0.08). At the Michigan facility, five of the EDB-exposed workers died from malignant
tumors, whereas 2.2 deaths were expected (p = 0.07). Excluded from this analysis were five
individuals from the Michigan facility who had worked with arsenicals in addition to EDB. Two of the
five died of respiratory cancer at ages 46 and 58, respectively. One had been exposed to arsenical
compounds for only 1 1/2 months, in contrast to 102 months of exposure to EDB; the other had been
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