o-TOLUIDINE CAS N°: 95-53-4 - UNEP Chemicals

OECD SIDS o-TOLUIDINE
5. TOXICITY ID: 95-53-4
DATE: 07.01.2005
260
Test substance : other TS: no data on purity
Remark : morphological transformation and ouabain resistance
Result : In the presence of an exogenous metabolic activation (primary rat liver
cells) o-Toluidine induced significant levels of transformation of 3T3 cells
relative to the solvent control.
This chemical also induced significant increases in the frequency of
Ouabain resistance mutants.
Test condition : Nonactivation transformation assay:
The transformation assay experimental design was adapted from that
reported by Kakunage, 1973 and involved treating 24-h-old cultures
seeded with 3 x 10E4 cells with 5 preselected doses of the test chemical, a
positive control and a solvent control. The dishes were incubated for 72h,
then washed and incubation continued for approx. 24 days with twiceweekly
refeedings. The assays were terminated by fixation with methanol
and staining with Giemsa.
Transformed foci were scored microscopically and consisted of foci of
denely piled-up cells with a desoriented criss-cross pattern that was
invasive into a uniformly stained, contiguous monolayer of cells.
Activation transformation assay:
Lethally x-radiated primary rat-liver cells were incubated for 3h with 3T3
cells and then treated with the test chemical for a total of 48h. Beginning 1-
2 days after the test chemical treatment had been completed, the
cocultures were treated with 0.05 µg/ml 12-o-tetradecenoyl-phorbol-13acetate
(TPA). The TPA posttreatment were continued biweekly for a total
of 3 weeks and discontinued one feeding interval prior to the termination of
the assay.
Ouabain resistance mutation assay:
24h-old-3T3 cell cultures with and without S9-mix (Aroclor induced rat-liver
cells) were incubated with the test chemical for 24h (4h for the S9
activation assays). Test chemical was removed and the cultures were refed
and maintained for 5-6 day expression period. At the end of this period
cells were trypsinzed, counted and repeated. Selection media containing 2
mM ouabain was added 1, 8, and 16 days after replaiting and the resultant
Quar colonies were fixed, stained and counted at 19-21 days post plating.
Reliability : (2) valid with restrictions
method evaluation program
01.12.2003 (377) (378)
Species : other: mouse; mammalian cell transformation assay
Sex :
Strain : other: embryonic mouse fibroblasts (C3H/10T1/2 Clone 8)
Route of admin. :
Exposure period : 24 hours
Frequency of treatm. :
Post exposure period :
Doses : 0, 250, 500, 750, 1000 µg/ml in culture medium
Result :
Control group : yes
Method : other: other: according Reznikoff, C.A. et al. (1973): Cancer Res. 33, 3231-
3238
Year : 1984
GLP : no data
Test substance : other TS: no data on purity
Result : Cytotoxicity increased dose-related:
survival at 500 µg/ml: 86 % of control; at 1000 µg/ml 52 of control
o-toluidine induced significant transformation at 500 µg/ml
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