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Toxicological information

Basic toxicokinetics

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Administrative data

Endpoint:
basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study not performed according to a guideline, but materials & methods and results are well described. Only absorption/excretion is studied.

Data source

Reference
Reference Type:
publication
Title:
Absorption of oxalic acid in rats by means of a 14C method
Author:
Bannwart, C., Hagmaier, V., Rutishauser
Year:
1979
Bibliographic source:
European Urology, Vol 5, p 276-277

Materials and methods

Objective of study:
absorption
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
13 female Wistar rats received a daily dose of 0.5 mL of a 1% solution of 14C-marked sodium oxalate (specific activity 29 nCi/mL) by gavage. This concentration corresponds to 17 mg oxalic acid/kg/day, which lies between the values found for humans 1-14 mg/kg/day) and rats (46-92 mg/kg/day). Feces and urine were collected every 24 hr and the amount of 14C-oxalate was determined by liquid scintillation counting.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Specific activity of the 14C-marked oxalate solution was 29 nCi/mL
Sodium oxalate was obtained from Merck, 14C-oxalate, H2C2O4 double brand was obtained from Amersham
Radiolabelling:
yes
Remarks:
14C

Test animals

Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: 200 g
- Individual metabolism cages: yes

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
not specified
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:

TEST SUBSTANCE
-Specific activity of 14C-marked solution: 29 nCi/mL

VEHICLE
- Concentration in vehicle: 1% sodium oxalate solution
- Amount of vehicle (if gavage): 0.5 mL
Duration and frequency of treatment / exposure:
Animals were treated once daily, over a 7-day period
Doses / concentrations
Dose / conc.:
0.5 other: mL of a 1% sodium oxalate solution
No. of animals per sex per dose:
One dose tested, 13 animals
Control animals:
no
Positive control:
No data
Details on study design:
No data
Details on dosing and sampling:
PHARMACOKINETIC STUDY (Absorption, distribution, excretion)
- Tissues and body fluids sampled: urine, faeces
- Time and frequency of sampling: daily (before the administration of every new dose of oxalate solution)
Statistics:
No data

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
The distribution of 14C-oxalate in the excretion of 13 animals during a 7-day period is 25.2% in urine and 73.4% in feces. The over-all recovery is 98.6%.
Details on distribution in tissues:
No data
Details on excretion:
The distribution of 14C-oxalate in the excretion of 13 animals during a 7-day period is 25.2% in urine and 73.4% in feces. The over-all recovery is 98.6%.

Metabolite characterisation studies

Metabolites identified:
not specified

Any other information on results incl. tables

The following table is reproduced from the publication. It summarizes the distribution of 14C-oxalate between faeces and urine in 13 animals for 7 days (1 daily dose = 100%)

Animal no.

Feces, %

Urine, %

1

73.5

14.0

2

50.7

33.1

3

74.2

42.0

4

58.2

31.9

5

67.8

22.9

6

65.0

33.2

7

84.9

20.1

8

67.2

26.6

9

80.1

27.8

10

80.5

20.9

11

99.5

18.5

12

72.4

30.3

13

79.5

15.6

_

x

73.4

25.2

Total

98.6%

s

12.4

6.9

Applicant's summary and conclusion

Conclusions:
Under the conditions of the current study, the distribution of 14C-oxalate in the excretion of 13 animals during a 7-day period is 25.2% in urine and 73.4% in feces. The over-all recovery was 98.6%.
No bioaccumulation potential based on study results
Executive summary:

13 female Wistar rats received a daily dose of 0.5 mL of a 1% solution of 14C-marked sodium oxalate (specific activity 29 nCi/mL) by gavage. This concentration corresponds to 17 mg oxalic acid/kg/day, which lies between the values found for humans 1-14 mg/kg/day) and rats (46-92 mg/kg/day). Feces and urine were collected every 24 hr and the amount of 14C-oxalate was determined by liquid scintillation counting.

The distribution of 14C-oxalate in the excretion was 25.2% in urine and 73.4% in feces. The over-all recovery was 98.6%.