N-(1,3-Dimethylbutyl)-N

OECD SIDS
N-(1,3-DIMETHYLBUTYL)-N´-PHENYL-1,4-PHENYLENEDIAMINE
3. ENVIRONMENTAL FATE AND PATHWAYS ID: 793-24-8
DATE: 11.05.2005
t1/2 pH9 : at °C
t1/2 pH 7 : 8 - 14 hour(s) at 26 °C
Deg. product : Yes
Method : other: similar to OECD 111
Year : 2003
GLP : No
Test substance : other TS: 6PPD, purity > 98 %
Deg. products : 122-37-2 204-538-9 4-anilinophenol
Method : Study design similar to OECD Guideline 111 but environmental parameters
modified to facilitate interpretation of ecotox studies.
Radiation, redox (aerobic instead of anaerobic), and nutrient medium
conditions simulated those used in ecotoxicological tests.
Test 1: Kinetics of primary degradation and major transformation product
studied in the light at 50 °C in buffer pH 7
Test 2: Kinetics of primary degradation and major transformation product
studied in the light at 26 °C in buffer pH 7
Test 3: Kinetics of primary degradation and major transformation product
studied in the light at 26 °C in algae nutrient solution
In both tests analytical monitoring of test substance and main metabolite
(4-hydroxydiphenylamine) using HPLC with UV detection
Result : 6PPD degradation in aerobic solutions is dependent on the temperature
and on heavy metals. In aerobic buffer at 50 °C the half life of 6PPD is
about 5 h, which is increased to about 14 h at 26 °C. In algae medium the
half life period was significantly decreased to 8 h at the same temperature.
4-Hydroxydiphenylamine was identified as the major aromatic intermediate
of 6PPD degradation under all conditions.
Test 1
buffer solution pH 7, 50 °C
Half life periods of 6PPD 5 h
Maximum formation of 4-Hydroxy-diphenylamine 54 %*
Test 2
buffer solution pH 7, 26 °C
Half life periods of 6PPD 14 h
Maximum formation of 4-Hydroxy-diphenylamine 99 %*
Test 3
nutrient medium pH 7, 26 °C
Half life periods of 6PPD 8 h
Maximum formation of 4-Hydroxy-diphenylamine 75 %*
* maximum concentration of 4-hydroxydiphenylamine divided by initial
concentration of 6PPD
Test condition : All tests were done under the following conditions: - The Erlenmeyer flask
was irradiated with a lamp at 8000 lux.
- All solutions were at pH 7 and air saturated
Test 1: 50 °C, buffer medium
Test 2: 26 °C, buffer medium
Test 3: 26 °C, algae nutrient medium
The buffer medium was sodiumdihydrogen phosphate 0.1 mol/l, adjusted to
pH 7 with NaOH.
The algae nutrient medium was adjusted to pH 7 and passed through a
sterile filter before use:
Concentration in test solution [mg/L]:
NaHCO3 50
NH4Cl 15
MgCl2 x 6H2O 12
CaCl2 x 2H2O 18
MgSO4 x 7H2O 15
KH2PO4 1.6
FeCl3 x 6H2O 0.08
Na2EDTA x 2H2O 0.1
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