SUBSTANCE PROFILES

1-Amino-2,4-Dibromoanthraquinone

CAS No. 81-49-2

Reasonably anticipated to be a human carcinogen

First Listed in the Eleventh Report on Carcinogens (2004)

Carcinogenicity

1-Amino-2,4-dibromoanthraquinone (ADBAQ) is reasonably

anticipated to be a human carcinogen based on sufficient evidence from

studies in experimental animals. Orally administered ADBAQ

significantly increased the incidences of benign and/or malignant

tumors at multiple tissue sites in two species of animals. ADBAQ

caused benign and malignant liver tumors in rats and mice of both

sexes; tumors of the large intestine, kidney, and urinary bladder in

male and female rats; and tumors of the forestomach and lung in male

and female mice (NTP 1996). 

Two cohort studies evaluated the risk of cancer among workers in

plants manufacturing anthraquinone dyes; however, it is not known

whether workers were exposed specifically to ADBAQ (Gardiner et al.

1982, Delzell et al. 1989). Some evidence suggests that anthraquinone

dye workers may have an increased risk of cancer. Significant excesses

of esophageal and prostate cancer occurred among workers in some

areas of a Scottish anthraquinone dyestuffs plant, and excesses of lung

and central nervous system cancer occurred among workers at a New

Jersey anthraquinone dye and epichlorohydrin plant (Barbone et al.

1992, 1994, Sathiakumar and Delzell 2000). Nevertheless, estimates

of risk in all studies were based on small numbers of cancer deaths,

and workers may have been exposed to other carcinogens. 

Additional Information Relevant to Carcinogenicity

Evaluation of ADBAQ’s genetic effects has been hindered by ADBAQ’s

limited solubility. ADBAQ caused mutations in some strains of bacteria

but not in rodent cells, which were tested at lower concentrations

(Haworth et al. 1983, NTP 1996). In mammalian cells, ADBAQ induced

chromosomal aberrations (changes in chromosome structure or number)

and sister chromatid exchange; however, the results varied between

laboratories and between trials at the same laboratory (Loveday et al. 1990,

NTP 1996). Point mutations in the ras proto-oncogene (a gene potentially

associated with cancer) occurred at a higher frequency in forestomach and

lung tumors from the two-year carcinogenicity study of ADBAQ-exposed

mice than in spontaneous tumors from control mice not exposed to

ADBAQ. The predominant types of mutations were A to T transversions

and A to G transitions, suggesting that ADBAQ or its metabolites target

adenine bases in the ras proto-oncogene (Hayashi et al. 2001). 

ADBAQ is rapidly absorbed from the gastrointestinal tract and

distributed to most soft tissues. The majority of ADBAQ is

metabolized, and both ADBAQ and its metabolites are excreted in the

feces and urine. However, the metabolites of ADBAQ have not been

identified (NTP 1996). 

The mechanism by which ADBAQ causes cancer is not known;

however, there is no evidence to suggest that mechanisms of tumor

induction observed in experimental animals would not occur in humans.

Four other anthraquinones (2-aminoanthraquinone, 1-amino-2-

methylanthraquinone, danthron [1,8-dihydroxyanthraquinone], and

disperse blue 1) are listed in the Report on Carcinogens as reasonably

anticipated to be human carcinogens.

Properties 

ADBAQ has a molecular weight of 381.0 and is a member of the class

of aminoanthraquinones. It occurs as a reddish-brown to orange

powder with a melting point of 221°C. ADBAQ is insoluble in water,

has an estimated log octanol-water partition coefficient of 5.31, and a

vapor pressure of 1.4 × 10-9 mm Hg at 25°C (NTP 1996,

ChemFinder 2003, HSDB 2003).

Use

ADBAQ and other aminoanthraquinones are key intermediates for

production of almost all anthraquinone dyes (HSDB 2003).

Anthraquinones, including ADBAQ, are widely used as starting

material for the manufacture of vat dyes. Vat dyes are a class of waterinsoluble dyes that can easily be reduced to a water-soluble and usually

colorless form. In this form, they are readily impregnated into fibers

and textiles. Oxidation then produces an insoluble colored form that

is remarkably fast to washing, light, and chemicals. Vat dyes typically

are used with cotton, wool, and cellulose acetate (NTP 1996). 

Production

ADBAQ is prepared from 1-aminoanthraquinone by bromination in

dilute mineral acids (HSDB 2003). ADBAQ is not produced in the

United States, but is available from at least one supplier (ChemSources

2003, SRI 2003). U.S. production of all vat dyes totaled 14 million

kilograms (31 million pounds) in 1991 (NTP 1996). 

Exposure

ADBAQ is not known to be formed naturally in the environment, but

may be released into the environment during its production or

through its use in production of anthraquinone dyes (HSDB 2003).

ADBAQ was detected in raw wastewater of a dye manufacturing plant

(in four of eight samples, at concentrations of 92 to 170 ppb).

However, it was not detected in the final effluent before its release into

a nearby river, nor in sediments from the river. This finding suggests

that ADBAQ may have been biodegraded or adsorbed to sludge

during wastewater treatment (HSDB 2003). 

Exposure to ADBAQ would be primarily through dermal contact.

Because ADBAQ has a very low vapor pressure, inhalation exposure to

vapor is unlikely; however, contaminated dust particles could be inhaled.

No information was found on occupational exposure specifically to

ADBAQ or to anthraquinone dyes in general, but epidemiological studies

indicated occupational exposure to anthraquinone dyes in a New Jersey

dye and resin manufacturing plant (Sathiakumar and Delzell 2000). 

Regulations and Guidelines

No regulations or guidelines relevant to reduction of exposure specifically to ADBAQ

were identified.

REFERENCES

Barbone, F., E. Delzell, H. Austin and P. Cole. 1992. A case-control study of lung cancer at a dye and resin

manufacturing plant. Am J Ind Med 22(6): 835-49.

Barbone, F., E. Delzell, H. Austin and P. Cole. 1994. Exposure to epichlorohydrin and central nervous system neoplasms at a resin and dye manufacturing plant. Arch Environ Health 49(5): 355-8.

Bolton, J. L., M. A. Trush, T. M. Penning, G. Dryhurst and T. J. Monks. 2000. Role of quinones in toxicology. Chem Res Toxicol 13(3): 135-60.

ChemFinder. 2003. 1-Amino-2,4-Dibromoanthraquinone. CambridgeSoft Corporation.

http://www.chemfinder.camsoft.com and search 81-49-2.

ChemSources. 2003. 1-Amino-2,4-Dibromoanthraquinone. Chemical Sources International, Inc.

http://www.chemsources.com and search CAS number 81-49-2.

Delzell, E., M. Macaluso and P. Cole. 1989. A follow-up study of workers at a dye and resin manufacturing

plant. J Occup Med 31(3): 273-8.

Gardiner, J. S., S. A. Walker and A. J. MacLean. 1982. A retrospective mortality study of substituted

anthraquinone dyestuffs workers. Br J Ind Med 39(4): 355-60.

Haworth, S., T. Lawlor, K. Mortelmans, W. Speck and E. Zeiger. 1983. Salmonella mutagenicity test results

for 250 chemicals. Environ Mutagen 5 Suppl 1: 1-142.

Hayashi, S., H. H. Hong, K. Toyoda, T. V. Ton, T. R. Devereux, R. R. Maronpot, J. Huff and R. C. Sills. 2001.

High frequency of ras mutations in forestomach and lung tumors of B6C3F1 mice exposed to 1-amino2,4-dibromoanthraquinone for 2 years. Toxicol Pathol 29(4): 422-9.

HSDB. 2003. Hazardous Substances Database. 1-Amino-2,4-Dibromoanthraquinone. National Library of

Medicine. Last reviewed: 1/31/96. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB and search

Br

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REPORT ON CARCINOGENS, ELEVENTH EDITION
SUBSTANCE PROFILES

REPORT ON CARCINOGENS, ELEVENTH EDITION

CAS number. Last accessed: 12/15/03.

Loveday, K. S., B. E. Anderson, M. A. Resnick and E. Zeiger. 1990. Chromosome aberration and sister chromatid exchange tests in Chinese hamster ovary cells in vitro. V: Results with 46 chemicals. Environ

Mol Mutagen 16(4): 272-303.

NTP. 1996. Toxicology and Carcinogenesis Studies of 1-Amino-2,4-Dibromoanthraquinone in F344/N Rats

and B6C3F1 Mice (Feed Studies). Technical Report Series No 383. Research Triangle Park, NC:

National Toxicology Program.

Sathiakumar, N. and E. Delzell. 2000. An updated mortality study of workers at a dye and resin manufacturing plant. J Occup Environ Med 42(7): 762-71.

SRI. 2003. Directory of Chemical Producers. http://dcp.sric.sri.com/Public/ (Visitor Search).