Registration Dossier

Administrative data

Endpoint:
dissociation constant
Type of information:
experimental study
Adequacy of study:
key study
Study period:
7 July 1993 - 28 September 1994
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report Date:
1995

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 112 (Dissociation Constants in Water)
Deviations:
not specified
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Test material: Simazine (pure)
- Appearance: White powder
- Batch No.of test material: Ref 766
- Expiration date of the batch: Two years from date of manufacture
- Purity: 99.5%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: In the dark at 4°C

Results and discussion

Dissociating properties:
yes
Dissociation constantopen allclose all
No.:
#1
pKa:
1.49
Temp.:
20 °C
Remarks on result:
other: Mean of 6 values for Test 1
No.:
#2
pKa:
1.75
Temp.:
20 °C
Remarks on result:
other: Mean of 7 values for Test 2
No.:
#3
pKa:
1.68
Temp.:
20 °C
Remarks on result:
other: Mean of 7 values for Test 3

Applicant's summary and conclusion

Conclusions:
The dissociation constant for simazine (pure) has been determined as pKa = 1.65 at 20°C.