m-Cresol - ipcs inchem

OECD SIDS
p-CRESOL
5. TOXICITY ID: 106-44-5
DATE: 24.05.2004
adduct with a relative adduct level of 0.28 x 10(exp)-7.
Oxidized p-Cresol to a quinone methide and than incubated with calfthymus
DNA resulted in 5 major adducts and a relative adduct level of
20.38 x 10(exp)-7.
The DNA adducts formed by activation of p-cresol with either horseradish
peroxidase or microsomes were the same as that produced by the quinone
methide of p-cresol.
Reliability : (2) valid with restrictions
no validated test method
Flag : Critical study for SIDS endpoint
06.02.2004 (162)
5.6 GENETIC TOXICITY ‘IN VIVO‘
274
Type : Dominant lethal assay
Species : mouse
Sex : male
Strain : ICR
Route of admin. : gavage
Exposure period : Single dose
Doses : 0, 100, 275, 550 (650) mg/kg bw diluted in corn oil
Result : negative
Method : other: EPA OTS 798.5450
Year : 1989
GLP : yes
Test substance : other TS: p-cresol, 99.8% pure
Method : Dose selection based upon the results of a dose range-finding assay
Number of animals:
25 males/group 50 females/group,
vehicle control: corn oil,
positive control: Triethylenemelamine (TEM)
Due to high mortality and toxicity in the 650 mg/kg bw-group during the first
week mice were removed from the study. Two weeks after the initiation of
the assay another group of males dosed with 550 mg/kg bw was assigned
as the new high dose to be evaluated.
Mating scheme:
1 male was mated with 2 virgin females for a period of up to 5 days. Then
females were removed and housed in groups for subsequent necropsy 14
days after the midweek of mating for evidence of pregnancy; the males
were rested for 2 days and then mated with 2 new females. This mating
sequence was followed for 6 consecutive weeks.
Observation of all animals for toxic effects and/or mortality, at termination
record of male body weight, determination of fertility index, total number of
implantations. dead implantations, proportion of females with 2 or more
dead implants, dead implants/total implants
Statistical methods:
Chi-square test, analysis of variance (ANOVA), Dunnett's one-tailed t test
Result : Mortality:
650 mg/kg bw: 10/25 males within the first week;
as signs of toxicity mice exhibited rapid breathing, several became languid
with mild clonic convulsions and squinted eyes and were prostrate and had
scruffy coats
550 mg/kg bw: 6/25 males died during the test
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