Registration Dossier

Administrative data

Endpoint:
hydrolysis
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: A modern guideline study performed to GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report date:
1998

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
EPA Guideline Subdivision N 161-1 (Hydrolysis)
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
603-373-3
EC Number:
603-373-3
Cas Number:
129909-90-6
Molecular formula:
C10H19N5O2
IUPAC Name:
603-373-3
Details on test material:
Specific activity 22.7 mCi/mmole.
Radiolabelling:
yes

Study design

Analytical monitoring:
yes
Details on sampling:
Duplicate units at 0, 6, 10, 15, 20, 24 and 30 days after application.
Buffers:
pH 5.0 buffer - 0.01M sodium acetate adjusted to pH 5.0 with 0.01 M acetic acid solution and 1.0 M sodium hydroxide solution.
pH 7.0 buffer - 0.01 M sodium acetate adjusted to pH 7 with 0.01M acetic acid solution.
pH 9.0 buffer - 0.01M sodium borate adjusted to pH 9 with 1.0 M acetic acid solution.
Details on test conditions:
Untis maintained in the dark at 25 degrees C +/- 1.0.
Duration of testopen allclose all
Duration:
30 d
pH:
5
Temp.:
25
Initial conc. measured:
1.1 other: ppm
Duration:
30 d
pH:
7
Temp.:
25
Initial conc. measured:
1.1 other: ppm
Duration:
30 d
pH:
9
Temp.:
25
Initial conc. measured:
1.1 other: ppm
Number of replicates:
Duplicated units

Results and discussion

Test performance:
Average mass balance of between 100.5 to 101.0% for each pH buffer indicating no volatiles produced.
Transformation products:
yes
Identity of transformation products
No.:
#1
Reference
Reference substance name:
Unnamed
IUPAC name:
DCA MKH 3586
Identifier:
other:
Identity:
DCA MKH 3586
Details on hydrolysis and appearance of transformation product(s):
DCA MKH 3586 major metabolite in pH 9 buffer at 28.5% at 30 days.
Total recovery of test substance (in %)open allclose all
% Recovery:
100.5
pH:
5
Temp.:
25 °C
Duration:
30 d
% Recovery:
101.5
pH:
7
Temp.:
25 °C
Duration:
30 d
% Recovery:
72.1
pH:
9
Temp.:
25 °C
Duration:
30 d
Dissipation DT50 of parent compound
pH:
9
Temp.:
25 °C
DT50:
65.25 d
St. dev.:
0.998
Type:
(pseudo-)first order (= half-life)

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
[Triazolinone-5-14C]MKH 3586 is stable at pHs 5 and 7 but had a half live in pH 9 of 65 days. The major degradate produced at pH 9 was DCA MKH 3586.
Executive summary:

The hydrolysis of radiolabelled MKH 3586 was studied at pH 5, 7 and 9 at 25 degrees C in the dark for 30 days.

The test compound was stabe at pH 5 and 7. At pH 9 the test compound had a half life of 65 days and the major degradate was DCA MKA 3586 which accounted for 28.5% applied radioactivity at 30 days.