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

OECD SIDS o-TOLUIDINE
The lowest test result obtained for Daphnia magna was in a GLP-test according to the OECD TG
202. An NOEC of 0.0126 mg/l and a LOEC of 0.04 mg/l were determined for the endpoint
reproduction (CERI, 1996e).Chronic toxicity towards Daphnia magna was investigated also in a
test according to the Dutch Standardization Organization Method NEN 6502. A 21 d-EC50 of
2.2 mg/l was obtained for the endpoint immobilisation. Endpoints population growth and length
were also observed. For the endpoint population growth, a LRCT value (lowest rejected
concentration tested) of 0.1 mg/l was reported (Maas-Diepeveen and van Leeuwen, 1986). This
value is similar to a LOEC (lowest observed effect concentration). The test was conducted with 17
anilines. The test concentrations were represented by the means of one aniline (2,4-dichloroaniline):
0.01, 0.032, 0.1, 0.32, 1.0, 3.2, 10.0 mg/l. In the summary table only the LOECs of the test
substances were given. For o-toluidine (LOEC 0.1 mg/l) a NOEC of 0.032 mg/l can be derived in
respect to the tested concentrations.
In an 8 day cell multiplication inhibition test with Microcystis aeruginosa (blue-green algae) an EC3
of 0.31 mg/l was determined. This result is similar to a NOEC. The test was designed by the
Bringmann (1975): continuous light, at 27 °C and pH 7 (Bringmann, 1975; Bringmann and Kuehn,
1978).
Additionally, the toxicity of o-toluidine towards the algae Selenastrum capricornutum was tested
with the OECD TG 201. A NOEC of 2.91mg/l was determined for the endpoint biomass and 31
mg/l for the endpoint growth rate. Both are measured concentrations (CERI, 1996c).
Table 11 Tests on chronic toxicity of o-toluidine to Daphnia and algae
Species Endpoint Parameter Effects Reference IUCLID
Daphnia magna
(crustacean)
Daphnia magna
(crustacean)
Microcystis aeruginosa
(blue-green algae)
Selenastrum
capricornutum (green
algae)
Growth of
population
21 d- NOEC
21 d-LOEC
Immobilization 21 d-EC50 2.2 mg/l (n)
Growth of
population
Length of
Daphnia
Cell
multiplication
Growth rate
21 d-LRCT*
assumed NOEC
0.0126 mg/l (n)
CERI, 1996e
0.04 mg/l (n)
0.1 mg/l (n)
0.032 mg/l (n)
21 d-LRCT* 1.0 mg/l (n)
8 d-EC3
72 h-ErC10
0.31 mg/l (n)
39.1 mg/l
* LRCT = Lowest rejected concentration tested with effect (similar to LOEC)
Maas-Diepeveen
and van
Leeuwen, 1986
Bringmann, 1975;
Bringmann and
Kuehn, 1978
4.5.2
4.5.2
UNEP PUBLICATIONS 39
4.3
CERI , 1996c 4.3