Benzoic acid, 4-[(1-oxodecyl)oxy]-

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: well performed GLP and OECD guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/CaOlaHsd

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Netherlands, B.V. Postbus 6174, NL-5960 AD Horst / The Netherlands
- Age at study initiation: 8-12 weeks
- Weight at study initiation: 16 - 24 g (ordered)
- Housing: Individual in Makrolon type-2 cages with softwood bedding
- Diet (e.g. ad libitum): Pelleted standard Kliba 3433 mouse maintenance diet, ad libitum
- Water (e.g. ad libitum): Community tap water, ad libitum
- Acclimation: yes

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 30-70
- Air changes (per hr): 14-15
- Photoperiod (hrs dark / hrs light): 12 h light / 12 h dark

Vehicle:

dimethyl sulphoxide

Concentration:

10, 25, 50%

No. of animals per dose:

4

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Positive control results:

EC3 = 7.1 % (w/v)

Parameter:

SI

Remarks on result:

other: group / test item concentration (%) / S.I. 2 / 10 / 1.1 3 / 25 / 1.3 4 / 50 / 1.4

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: group / test item concentration (%) / dpm per lymph node 1 / 0 (control)/ 817 2 / 10 / 938 3 / 25 / 1032 4 / 50 / 1158

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

A test item is regarded as a sensitizer in the LLNA if the exposure to one or more test concentrations resulted in 3-fold or greater increase in incorporation of 3HTdR compared with concurrent controls, as indicated by the STIMULATION INDEX (S.I.).

In this study STIMULATION INDICES of 1.1, 1.3 and 1.4 were determined with the test item at concentrations of 10 %, 25 % and 50 % (w/v), respectively, in dimethylsulfoxide (DMSO). The test item was therefore found to be a non-sensitizer when tested at up to the highest applicable concentration of 50 % (w/v) in dimethylsulfoxide (DMSO).

Executive summary:

In order to study a possible contact allergenic potential of the test item was tested according to OECD Guideline 429. Following this guideline three groups each of four female mice were treated daily with the test item at concentrations of 10 %, 25 % and 50 % (w/v) in dimethylsulfoxide (DMSO) by topical application to the dorsum of each ear lobe (left and right) for three consecutive days. 50 % was the highest technically applicable concentration in the vehicle. A control group of four mice was treated with the vehicle (dimethylsulfoxide (DMSO)) only. Five days after the first topical application the mice were injected intravenously into a tail vein with radio-labelled thymidine (3H-methyl thymidine). Approximately five hours after intravenous injection, the mice were sacrificed, the draining auricular lymph nodes excised and pooled per group. Single cell suspensions of lymph node cells were prepared from pooled lymph nodes which were subsequently washed and incubated with trichloroacetic acid overnight. The proliferative capacity of pooled lymph node cells was determined by the incorporation of 3H-methyl thymidine measured in a ß-scintillation counter.

All treated animals survived the scheduled study period.

No clinical signs were observed.

At concentrations of 10, 25, 50 % S.I. values of 1.1, 1.3, and 1.4 were determined respectively.

Calculation of the EC3-value was not performed because no test concentrations produced a STIMULATION INDEX (S.I.) of 3 or higher.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Migrated from Short description of key information:
In the LLNA STIMULATION INDICES of 1.1, 1.3 and 1.4 were determined at concentrations of 10 %, 25 % and 50 % (w/v), respectively, in dimethylsulfoxide. The test item was therefore found to be a non-sensitizer when tested up to the highest applicable concentration of 50 % (w/v).

These findings are supported by the negative outcome of the GPMT.

Justification for selection of skin sensitisation endpoint:
From two reliable studies with consistent results the more contemporary one was representatively selected.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The outcome of a LLNA was negative (S.I. values < 3) at doses up 50% which was the highest dose applicable. This result was supported by the negative outcome of a GPMT (0% response after re-challenge). Since these findings do not meet the criteria for classification according to the rules laid down in Directive 67/548/EEC and in Regulation (EC) No 1272/2008, classification is not warrantable.