Appendix D - Dossier (PDF) - Tera

date: 20–JUL–2005
5. Toxicity Substance ID: 71–43–2
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Type: Sister chromatid exchange assay
System of testing: Chinese hamster ovary cells
Concentration: 16, 50, 160, 500, 1600, 5000 µg/ml
Metabolic activation: with and without
Result: negative
Method: OECD Guide–line 479
Year: 1986
GLP: no data
Test substance: other TS
Remark: Benzene was dissolved in dimethylsulphoxide. Metabolic
activation (S9) was derived from the liver of
Aroclor–1254–induced male Sprague–Dawley rats. Cells were
treated with benzene for 2 hours, bromodeoxyuridine was
added and incubation continued for 24 hours. The cells were
then placed in fresh medium with colcemid and incubated for
2–3 hours. When S9 was present, cells were incubated for 2
hours as above except foetal bovine serum was omitted to
prevent the binding of serum proteins to short–lived, highly
reactive intermediates. After the 2 hours, cells were
washed, suspended in complete medium and incubated for 26
hours, colcemid being added for the final 2–3 hours.
Assessment of SCEs for both treatment regimes were made.
Cyclophosphamide and mitomycin C were used as positive
controls in the presence and absence of S9 respectively.
Benzene was tested at levels of 16, 50, 160 and 500 µg/ml in
the absence of S9 and at 16, 50, 160, 500, 1600 and 5000
µg/ml in the presence of S9. No increase in the number of
SCEs were found. Subsequent analyses of the data at benzene
levels of 100, 250, 500, 750 and 1000 µg/ml in the absence
of S9 showed an increase in SCEs. Other investigators have
reported negative SCE results in this cell line when treated
in the absence and presence of a metabolic activation system
(Douglas G.R. et al. Prog. Mutation Res. 5, 359–366, 1985;
Lane A.M. et al. ibid. 5, 451–455, 1985; Natarajan A.T. et
al. ibid. 5, 433–4370, 1985), in Chinese hamster V79 cells
in the absence and presence of activation (van Went G.F.
ibid. 5, 469 477, 1985) and in rat liver cells (Priston
R.A.J. & Dean B.J. ibid. 5, 387–395, 1985).
Source: BP Chemicals Ltd LONDON
Test substance: Laboratory reagent grade; >=99% pure.
13–DEC–1996 (457) (458)
Type: Sister chromatid exchange assay
System of testing: Chinese hamster V79 cells
Metabolic activation: no data
Result: positive
Method: other
GLP: no data
Test substance: no data
Remark: A statistically significant increase in the number of SCEs
was found in cultures treated with
anti–benzene–diol–epoxide, syn–benzene–diol–epoxide,
hydroquinone, catechol, 1,2,4– and 1,2,3–trihydroxybenzene.
Appendix D: Benzene SIDS Dossier
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