m-Cresol - ipcs inchem

OECD SIDS
m- / p-CRESOL
Atrophy and regenerative changes in the nasal epithelia and forestomach were seen after exposure
to p-cresol and m/p-cresol, presumably as direct result of the irritant effects of these chemicals.
The no observed adverse effect levels (NOAELs) for m-cresol, p-cresol and m/p-cresol (28d- and
90d-studies) were generally ≥ 50 mg/kg bw/day in rats and mice:
Table 9:
NOAEL Values for Systemic Toxicity From Repeated Dose Toxicity Studies
NOAELs m-Cresol p-Cresol m/p-Cresol
Rat(m, f):
28d, feeding, 252 mg/kg bw/day (m, f) 87 mg/kg bw/day (m)
83 mg/kg bw/day (f)
90 mg/kg bw/day (m),
95 mg/kg bw/day (f)
13 w, feeding 123 mg/kg bw/day (m)
254 mg/kg bw/day (f)
13 w gavage 50 mg/kg bw/day (m)
150 mg/kg bw/day (f)
Mouse (m, f)
28 d feeding 193 mg/kg bw/day (m)
66 mg/kg bw/day (f; LOEL:
increase in relative liver weight
without histopathological
correlate)
50 mg/kg bw/day(m, f)
163 mg/kg bw/day (m)
207 mg/kg bw/day (f)
50 mg/kg bw/day (m)
200 mg/kg bw/day (f)
13 w feeding 776 mg/kg bw/day (m)
472 mg/kg bw/day (f)
The NOAEL for repeated dose (90d-study) of o-cresol was 50 mg/kg bw/day for mice and rats
(UNEP 1998).
3.1.6 Mutagenicity
in vitro
(A) Gene mutation
m-Cresol
m-Cresol was tested negative in several Ames tests with various Salmonella typhimurium strains
and using preincubation or standard methodology (e.g. Haworth et al. 1983, Pool and Lin 1982).
The studies gave no indication of gene mutation with and without metabolic activation.
In addition, there is a mouse lymphoma assay with a negative result (with and without S9-mix,
Hazleton Lab. Am. 1988a).
p-Cresol
p-Cresol was tested negative in several Ames tests with various Salmonella typhimurium strains and
using preincubation or standard methodology (e.g. Haworth et al., 1983, Pool and Lin, 1982). The
studies gave no indication of gene mutation with and without metabolic activation.
In addition, there is a mouse lymphoma assay (with and without S9-mix) with a negative result
(Hazleton Lab. Inc. 1988e).
UNEP PUBLICATIONS 25