Dipotassium disulphate

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: This study was selected as the key study because the information provided for the hazard endpoint is sufficient for the purpose of classification and labelling and/or risk assessment.

Data source

Reference

Reference Type:

publication

Title:

Absorption of Sulfate Ions in the Rat Lung

Author:

Charles JM & Menzel DB

Year:

1975

Bibliographic source:

Res. Commun. Chem Pathol Pharmacol., 12(2}:389-396

Materials and methods

Objective of study:

absorption

Principles of method if other than guideline:

35S was instilled into the trachea of anesthetized rats, at various time points lungs were removed and assayed for 35S radioactivity

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Sodium sulphate

EC Number:

231-820-9

EC Name:

Sodium sulphate

Cas Number:

7757-82-6

IUPAC Name:

disodium sulfate

Details on test material:

- Purity: not reported

Radiolabelling:

yes

Remarks:

35S-sulfate ions

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 150-200 g

Administration / exposure

Route of administration:

intratracheal

Vehicle:

other: isotonic sucrose solution (300 mM, pH 7.4)

Details on exposure:

TYPE OF INHALATION EXPOSURE: other: instilled via a tracheal cannula into anesthetized animals

EXPOSURE PROCEDURE
Sprague Dawley rats, weighing 150-200 g, were anesthetized with pentobarbital. After the animal was secured on its back to a board, the trachea was isolated and 2 cm of a 5 cm long plastic cannula (PE 240) was inserted into the trachea through a transverse incision to a point approximately
0.5 cm above the bifurcation of the trachea. The mounting board was placed in an upright position. One tenth millilitre of an isotonic sucrose solution (300 mM, pH 7.4) containing either 0.01, 0.10, or 1.00 mM 35S-Na2S04 (specific activity-0.65 µCi/mmole), was injected into the lungs via the trachea cannula through a 1.5 inch 22 gauge needle attached to a 100 µL syringe. The solution was injected over a 1 to 2 second interval.

Duration and frequency of treatment / exposure:

once

Doses / concentrations

Remarks:

Doses / Concentrations:
0.01, 0.10, or 1.00 mM

No. of animals per sex per dose / concentration:

0.01 mM - 11 rats
0.10 mM - 3 rats
1.00 mM - 3 rats

Details on dosing and sampling:

PHARMACOKINETIC STUDY (Absorption, distribution, excretion)
- Tissues and body fluids sampled: lung
- Time and frequency of sampling: 15, 30, 60 and 120 minutes after dosing

Results and discussion

Main ADME results

Type:

absorption

Results:

Amount of Na2S04 absorbed was proportional to initial concentration administered. Results suggested absorption occurred by nonsaturable process, such as simple diffusion. Half-life for sulphate absorption in the presence of sodium ions was 34.5 minutes.

Any other information on results incl. tables

Absorption of Sodium ^35S-Sulphate from the Rat Lung
Concentration of Na2SO4	No. of Animals	30 min. Absorption % dose	Sulphate Ion Amount µg
0.01	11	43.2	0.41
0.1	3	42.0	4.03
1.00	3	47.4	45.50

 

Applicant's summary and conclusion

Conclusions:

This study and the conclusions which are drawn from it fulfil the quality criteria (validity, reliability, repeatability).
A half-life of 34.5 minutes was observed.

Executive summary:

To investigate the absorption of ³⁵S-sulphate ions from the rat lung in the presence of sodium ions, 0.1 mL of isotonic sucrose solution containing the salt was instilled via a tracheal cannula into anesthetized animals. After various times the lungs were removed and assayed for ³⁵S-radioactivity. Sulphate ion absorption was found to be nonsaturable and proportional to the concentration of sulphate ion, with a t_1/2 = 34.5 minutes.