Cyclopentane, methoxy-

Endpoint summary

Description of key information

LLNA study: not skin sensitising

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

Study period:

21 November 2002 - 24 December 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to OECD test guidelines, and in compliance with GLP, and so the data is considered reliable without restriction.

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Specific details on test material used for the study:

- Analytical purity: 99.9%
- Lot/batch No.: 020618

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 17.3 to 20.5 g
- Housing: Individually housed in polycarbonate cages
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: Six days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21±3°C
- Humidity (%): 40 - 70%
- Photoperiod (hrs dark / hrs light): 12 hours light / 12 hours dark

IN-LIFE DATES: From: 21 November 2002 To: 24 December 2002

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

Preliminary study : 50% (v/v) and 100% (dosed as supplied)
Main study: 25%, 50% (v/v) and 100% (dosed as supplied)
The main study also included a vehicle control group.

No. of animals per dose:

1 female per dose in the preliminary study
4 females per dose level in the main study

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: In a vehicle trial, NZE was found to form a miscible, clear colourless liquid at 50% (v/v) in Acetone : olive oil (4:1 v/v).

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Criteria used to consider a positive response: Test substance is considered to be a sesitiser if at least one concentration tested results in a three-fold increase (relative to the concurrent vehicle control) in the incorporation of 3H-methyl Thymidine.

TREATMENT PREPARATION AND ADMINISTRATION: 25 µL of each preparation was applied to the dorsal surface of the ear using a micropipette. The test substance was spread over the entire dorsal surface of the ear using the tip of the micropipette.

Positive control substance(s):

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

Positive control results:

Comments: Within this study the positive control hexyl cinnamic aldehyde was applied at 10, 25, 50% (v/v) preparations in (4:1 v/v acetone/olive oil). Stimulation indicies of >3 were obtained at all concentrations.

Parameter:

SI

Value:

1.2

Test group / Remarks:

25% v/v

Parameter:

SI

Value:

1.3

Test group / Remarks:

50% v/v

Parameter:

SI

Value:

2.6

Test group / Remarks:

100% v/v

Interpretation of results:

GHS criteria not met

Conclusions:

None of the tested concentrations produced a test-control ratio greater than 3, so the substance is not regarded a potential sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

A skin sensitization study was conducted (Huntingdon Life Sciences, 2002, Study ZCE099) to determine the potential for the substance to cause delayed-action dermal effects. The Local Lymph Node Assay was used, performed according to OECD test guideline 429 and in compliance with GLP.

Groups of four mice were dosed for three consecutive days with test material in acetone : olive oil (4:1 v/v) at concentrations of 0 (vehicle control group), 25%, 50% (v/v), or 100% (test material used as supplied). Sensitization was determined in terms of the proliferative response from the draining auricular lymph nodes, measured by the uptake of ³H-Thymidine by beta-scintillation counting of lymph node cells.

None of the dose groups showed a threefold or greater response relative to the concurrent control group, and so the substance was not considered sensitizing.

Justification for classification or non-classification

A Skin Sensitization study concluded that the substance showed no sensitizing activity (LLNA study SI<3), on this basis the substance is not classified for skin sensitization under CLP regulation 1272/2008.

No information regarding the potential for the substance to cause respiratory sensitization.