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

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP laboratory study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A GLP Test was already exisitng on a similar substance.

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Hoeschst AG, Kastengrund, SPF breeding colony
- Age at study initiation: Not stated
- Weight at study initiation: Mean = 334 g
- Housing: Makrolon Type 4 cages on soft wood granulate in fullyl air-conditioned rooms in groups of 5 animals
- Diet (e.g. ad libitum): ad libitum, Altromin 3112 diet for guinea pigs and rabbits
- Water (e.g. ad libitum): ad libitum, tap water in plastic bottles
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 C
- Humidity (%): 55 +/- 20%
- Air changes (per hr): Not stated
- Photoperiod (hrs dark / hrs light): 12:12 dark:light

Route:

intradermal

Vehicle:

other: semi-liquid paraffin

Concentration / amount:

Intradermal induction was performed using 0.2% Branched CaDDBS in semi-liquid paraffin. Dermal induction were carreid out with 3% Branched CaDDBS in petrolatum. 0.1% Branched CaDDBS in petrolatum was selected for challenge treatment.

Route:

epicutaneous, open

Vehicle:

other: semi-liquid paraffin

Concentration / amount:

Intradermal induction was performed using 0.2% Branched CaDDBS in semi-liquid paraffin. Dermal induction were carreid out with 3% Branched CaDDBS in petrolatum. 0.1% Branched CaDDBS in petrolatum was selected for challenge treatment.

No. of animals per dose:

10 animals in the treatment group and 5 animals in the control group were used.

Details on study design:

Chronlogical description of the test procedure indicating the day at which the procedure was carried out:

Day 0: The body weights of the animals were determined. Guinea pigs were shaved mechanically over a dorsal area of 4x6 cm in the vicinity of the shoulders.

Day 1: Intradermal induction treatment: Two intradermal injections per animal of the following preparations. Injection sites 1, 2 and 3 were all within the dorsal area of 2 x 4 cm and were left uncovered.

Treated group:
Site 1: 2 x 0.1 mL of 50% Freund's adjuvant
Site 2: 2 x 0.1 mL of 0.2% solution of test substance in semi-liquid paraffin
Site 3: 2 x 0.1 mL of 0.2% solution of test substance in 50% Freund's adjuvant

Control and escort groups:
Site 1: 2 x 0.1 mL of 50% Freund's adjuvant
Site 2: 2 x 0.1 mL of semi-liquid paraffin
Site 3: 2 x 0.1 mL of 50% Freund's adjuvant

Days 1-7: The application area was examined for local tolerance. Any systemic toxic effects were recorded.

Day 8: Dermal induction treatment: 0.5 g of test substance preparation or the vehicle was applied to a 2 x 4 cm cellulose patch, which covered the area where intradermal injection had been made. The application area was kept for 48 hours under an occlusive bandage with an impermeable film and an elastic bandage.

Treatment group: 3% test substance in petrolatum
Control and escort group: petrolatum

Day 10: Occlusive bandage removed and irritant effects recorded.

Days 11-21: No treatment of control or treated group. Test animals kept under observation.

Days 15-18: Challenge treatment of escort group carried out in same way as that of control and treated groups (see days 22-25). Escort group (left flank): 1% Branched CaDDBS in petrolatum

Day 22: Dermal challenge treatment: One area of approximately 5 x 5 cm on the left flank was shaved mechanically. 0.5 g of the test substance preparation was applied to a 2 x 2 cm cellulose patch. The application area was then kept for 24 hours under an occlusive bandage with an impermeable film and an elastic bandage. Treated and control groups (left flank): 0.1% Branched CaDDBS in petrolatum.

Day 23: Occlusive bandage removed.

Day 24: Skin examined.

Day 25: Skin examined and body weights of test animals determined.

Challenge controls:

See details of study design.

Reading:

other:

Clinical observations:

No signs of irritation at 24 or 48 hours after removal of the occlusive bandage

Remarks on result:

other: Reading: other:. Clinical observations: No signs of irritation at 24 or 48 hours after removal of the occlusive bandage.

Reading:

1st reading

Group:

negative control

Remarks on result:

other: Data not available

Reading:

1st reading

Group:

test chemical

Remarks on result:

other: Data not available

Reading:

1st reading

Group:

positive control

Remarks on result:

other: Data not available

No signs of irritation were observed in the control and treatment groups 24 and 48 hours after removal of the occlusive bandage. No adverse effects on body weight gains were observed. The treated animals showed no clinical signs of intoxication throughout the study.

The intradermal injections with Freund's adjuvant (with and without test substance) casused severe erythema and oedema, indurations and encrustations. The application sites treated with the test substance showed very slight to well-defined erythema and very slight to slight oedema. Injections of the vehicle alone did not cause any sign of irritation. Due to these strong irritation reactions of the skin, 10% sodium dodecylsulfate was not applied at day 7.

After the removal of the patch at day 10, erythema and oedema, indurated adn encrusted skin as well as necrosis were observed at the application sites treated with Freund's adjuvant (with and without test substance). Additionally, the sites treated with test substance in Fruend's adjuvant exhibited open wounds in some cases. Very slight to well-defined erythema occurred at the application sites treated with the test substance in the vehicle.

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test substance showed no evidence of sensitisation.

Executive summary:

Testing for sensitising properties of Branched CaDDBS was performed in female Guinea pigs according to OECD Guideline 406 methods (Guinea pig maximization test). Intradermal induction was performed using 0.2% Branched CaDDBS in semi-liquid paraffin. Dermal induction was carried out with 3% Branched CaDDBS in petrolatum. 0.1% Branched CaDDBS in petrolatum was selected for the challenge treatment. Results show no evidence for sensitisation. Branched CaDDBS is therefore not a dermal sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

In cases where data on BABS Na salt is not available, data on analogue substances are used. The analogue substances used included: 1) the sodium salt of linear alkylbenzene sulfonate (commonly known as LAS or Na-LAS), 2) the calcium salt of branched alkylbenzene sulfonate (commonly known as Branched CaDDBS) and 3) the calcium salt of linear alkylbenzene sulfonate (commonly known as Linear CaDDBS). LAS is the sodium salt of linear alkylbenzene sulfonic acid with alkyl carbon chain lengths ranging from C10 to C13 and averaging 11.6. The primary structure is a C10 to C13 linear alkyl chain with a para-substituted benzene sulfonic acid sodium salt group attached at any of the secondary alkyl carbon positions. Branced CaDDBS is the calcium salt of branched alkylbenzene sulfonic acid with alkyl chain lengths ranging from C11 to C13. Linear CaDDBS is the calcium salt of linear alkylbenzene sulfonic acid with alkyl carbon chain lengths ranging from C10 to C14. BABS Na salt is the sodium salt of branched alkylbenzene sulfonic acid with alkyl chain lengths ranging from C11 to C13. The primary difference between LAS and BABS Na salt is the alkyl chain, branched vs. linear. The primary difference between Branched CaDDBS and BABS Na salt is the salt, calcium vs. sodium. Given their structural and functional similarities, LAS, Branched CaDDBS, and Linear CaDDBS are good analogues for read-across for instances where data are available on them but not on BABS Na salt. When studies on the analogues are available, all data are provided and the most conservative (most health protective) data is used for classification and labeling.

Testing was performed on two analogue substances Branched CaDDBS, and LAS. The first test, testing for sensitising properties of Branched CaDDBS, was performed in female Guinea pigs according to OECD Guideline 406 methods (Guinea pig maximization test). Intradermal induction was performed using 0.2% Branched CaDDBS in semi-liquid paraffin. Dermal induction was carried out with 3% Branched CaDDBS in petrolatum. 0.1% Branched CaDDBS in petrolatum was selected for the challenge treatment. Results show no evidence for sensitisation. Branched CaDDBS is therefore not a dermal sensitiser. The second test determined the potential of LAS to be sensitizing to skin. 10 male and 10 female guinea pigs were given intradermal injections of 25% test solution. Control animals (5 male and 5 female) were given injections of vehicle only. One week later, a second induction was done by dermal exposure to 25% test solution for 24 hrs. Control animals were again exposed to vehicle only. On day 21, the challenge exposure was performed. All animals were exposed to 12.5% test solution dermally. Exposure was for 24 hrs, with observations made at 48 and 72 hrs after the start of exposure. No positive reactions were noted. The test substance is not sensitizing. Based on the results of the two analogue substances, BABS Na salt is not sensitizing to skin.

Migrated from Short description of key information:

No evidence of sensitization  was observed in two guinea pig sensitization studies performed on analogue substances.  

Justification for selection of skin sensitisation endpoint:

The selected study is a GLP study done according to OECD Guideline 406.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the lack of reactions in two guinea pic sensitisation studies, BABS Na salt will not be classified under the DSD or CLP.