Benzenesulfonic acid, mono-C11-13-branched alkyl derivs., calcium salts

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented study in peer-reviewed publication conducted by experienced testing laboratory.

Data source

Reference

Reference Type:

publication

Title:

Metabolism of linear alkylate sulfonate and alkyl benzene sulfonate in albino rats

Author:

Michael, W.R.

Year:

1968

Bibliographic source:

Toxicol. Appl. Pharmacol. 12:473-485

Materials and methods

Objective of study:

metabolism

Principles of method if other than guideline:

The absorption, distribution, metabolism and elimination of Branched alkylbenzene sulfonate (radioactively labeled with 35S) were studied in male Charles River rats. The substance was administered as an aqueous solution.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Branched Alkyl benzene sulfonate (ABS)

IUPAC Name:

Branched Alkyl benzene sulfonate (ABS)

Details on test material:

Branched alkylbenzene sulfonate (ABS); alkyl chain length predominately C12 with indications of trace amounts of C11 and C13. On the average, the alkyl chain was 8 to 9 carbon atoms in length and contained 3 to 4 methyl branch points.

Radiolabelling:

yes

Remarks:

(radioactively labeled with 35S)

Test animals

Species:

rat

Strain:

other: Charles River albino

Sex:

male

Details on test animals or test system and environmental conditions:

The animals were housed in individual cages which permitted the separate collection of urine and feces. Food and water were provided ad libitum after dosing.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

Male rats (150-200 g) were fasted for 16 hours and given orally an aqueous solution containing AB35S. The dose was given in 1.0 mL volume. The urine was collected under toluene, removed daily, and refrigerated until it could be examined. The feces were removed each day and allowed to dry at room temperature. At the termination of the study, the animals were killed and selected organs and tissues were taken for radioassay.

Also, the route of absorption was determined by oral feeding of 40 mg of ABS to thoracic duct-cannulated rats. The lymph was collected from each animal in a single 42-hour fraction.

The enterohepatic circulation of the sufactant was quantifed by oral feeding of 1.2 mg of ABS to bile duct-cannulated rats and to rats prepared in a manner similar to the dual rat study described by Boquet and Fromageot. A cannula was inserted into the proximal end of the bil duct of Rat A and into the distal end of the bile duct in Rat B such that the bile from Rat A could flow through the cannula into the bile duct, and finally into the intestine of Rat B. A second cannula was inserted into the proximal end of the bile duct of Rat B so that this bile could be collected. AB35S was fed orally to Rat A. Urine and feces of Rats A and B and bile of Rat B were collected for 90 hours after dosing.

Duration and frequency of treatment / exposure:

See details of exposure section

Doses / concentrations

Remarks:

Doses / Concentrations:
0.6, 1.2, and 40.0 mg (averages of three animals per dose) for the excretion test, 1.2 mg/rat for the absorption and enterohepatic circulation tests.

No. of animals per sex per dose / concentration:

Three or five males per dose for the excretion test, six males for the absorption and enterohepatic tests.

Control animals:

not specified

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:

The compound was readily absorbed from the gastrointestinal tract (80-90% of the dose).

Details on distribution in tissues:

Primarily excreted in the bile.

Details on excretion:

Most of the absorbed 35S from orally administered AB35S was eliminated within 72 hours and 80-90% of the absorbed dose was eliminated in the bile.

Metabolite characterisation studies

Metabolites identified:

yes

Details on metabolites:

The metabolites isolated from the bile were found to be sulfophenyl carboxylates. One series of compounds (ABS-I) was found to contain two double bonds in the alkyl chain. Neither of these double bonds appear to be alpha-beta to the carboxyl group. The other fraction (ABS-II) seemed to contain only a saturated sulfophenyl carboxylate with eleven carbons in the carboxylate chain.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): no bioaccumulation potential based on study results
Branched alkylbenzene sulfonate (ABS) is readily absorbed by the gastrointestinal tract and rapidly excreted with its metabolites, primarily in the bile.

Executive summary:

The absorption, distribution, metabolism and elimination of Branched alkylbenzene sulfonate (radioactively labeled with 35S) were studied in male Charles River rats. The substance was readily absorbed by the gastrointestinal tract and rapidly metabolized and excreted in the bile.