2-(4-methylcyclohex-3-en-1-yl)propan-2-ol

Endpoint summary

Description of key information

Terpineol multiconstituent is not a skin sensitiser according to the results of an OECD 406 study.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2006-01-16 to 2006-02-23

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

GLP followed OECD, well conducted and documented study, substance details and certificate of analysis. However there are deviations: slight higher temperature, longer rest phase between induction and challenge, and insufficient number of test animals.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

slight higher temperature, longer rest phase between induction and challenge and insufficient number of test animals

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A study conducted according to Guideline OECD 406 before 2008 and is available on the registered substance.

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Centre de Production Animale, Olivet, France
- Weight at study initiation: between 359 g and 500 g
-housing: housed in groups of 2 or 3 in makrolon containers
-diet(ad libitum): pelleted guinea pig breeding diet, ad libitum
- Water (e.g. ad libitum): tap water from public distribution system, ad libitum
- Acclimatation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): between 20 and 25
- Humidity (%): between 30 and 49
-air changes: at least 10 cycles per hour
-photoperiod: 12 hours dark / 12 hours light

IN-LIFE DATES: From: 2006-01-16 To: 2006-02-23

Route:

intradermal and epicutaneous

Vehicle:

olive oil

Concentration / amount:

For maximal non necrotising concentration test (through intradermal injections): 100, 50, 25, 12.5, 6.25 and 3.125%
For maximal non irritant concentration (topical application): - Induction phase 100, 50,25, and 12.5% - Challenge 25, 12.5, 6.25 and 3.125%

Route:

epicutaneous, occlusive

Vehicle:

olive oil

Concentration / amount:

For maximal non necrotising concentration test (through intradermal injections): 100, 50, 25, 12.5, 6.25 and 3.125%
For maximal non irritant concentration (topical application): - Induction phase 100, 50,25, and 12.5% - Challenge 25, 12.5, 6.25 and 3.125%

No. of animals per dose:

For maximal non necrotising concentration test: 2 males
For maximal non irritant concentration: - Induction phase: 2 males
- Challenge phase: 1 male and 2 females

Details on study design:

RANGE FINDING TESTS: For maximal non necrotising concentration test (through intradermal injections): 100, 50, 25, 12.5, 6.25 and 3.125% (2 males)
For maximal non irritant concentration (topical application): - Induction phase 100, 50,25, and 12.5% (2 males) - Challenge 25, 12.5, 6.25 and 3.125% (1 male and 2 females)

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3 pairs of intradermal injections in treated group and 3 pairs of intradermal injections in control group on day 0 and 2nd induction topical application in both treated and control groups on 7th day
- Exposure period: 9 days
- Test groups: 10 males
- Control group: 5 males
- Site: inter scapular zone
- Frequency of applications: only once
- Concentrations:
- Intradermal injections: 2 intradermal injections of the test item diluted at 6.25 % in olive oil. 2 intradermal injections of Freund's Complete Adjuvant diluted at 50 % in a physiological saline solution. 2 intradermal injections of a mixture with equal volumes of Freund's Complete Adjuvant at 50% and the test item diluted at 12.5% in olive oil.
- Topical application: on the same zone, with the test item at 100%

B. CHALLENGE EXPOSURE
- No. of exposures: one time
- Day(s) of challenge: 2
- Exposure period: 24 h
- Test groups: 10 males
- Control group: 5 males
- Site: dorso-lombar zone
- Concentrations: for group 1 and 2 topical application under occlusive dressing at the following concentrations: 25 and 12.5 %
- Evaluation (hr after challenge): skin reactions at 24 and 48 h

Challenge controls:

5 males, topical application under occlusive dressing at the following concentrations: 25 and 12.5%

Positive control substance(s):

yes

Remarks:

alpha-hexylcinnamaldehyde (CAS No 101-86-0) and 2-mercaptobenzothiazole (CAS No 149-30-4)

Positive control results:

The test substances Hexylcinnamaldehyde (50, 25 and 12.5%) and 2-Mercaptobenzothiazole (50 and 25%) were used as a positive control and induce positive sensitization response

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

25%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

25%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

12.5%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

12.5%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

25%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

25%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

12.5%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

12.5%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

12.5%

No. with + reactions:

45

Total no. in group:

11

Remarks on result:

positive indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

48

Group:

positive control

Dose level:

12.5%

No. with + reactions:

18

Total no. in group:

11

Remarks on result:

positive indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

25%

No. with + reactions:

100

Total no. in group:

10

Remarks on result:

positive indication of skin sensitisation

Reading:

1st reading

Hours after challenge:

48

Group:

positive control

Dose level:

25%

No. with + reactions:

60

Total no. in group:

10

Remarks on result:

positive indication of skin sensitisation

No remarks

Interpretation of results:

not sensitising

Conclusions:

Terpineol multiconstituent should not be classified according to CLP Regulation (EC) No 1272/2008.

Executive summary:

In a skin sensitization study performed according to the OECD guideline 406 and conducted in compliance with GLP, Terpineol multiconstituent was tested in male albino guinea pigs using the Guinea pig Maximisation test method (10 treated animals and 5 control animals).

Preliminary studies were conducted to dertermine the maximal non necrotising concentration through intradermal injections and the maximal non irritant concentration by topical application. Six concentrations were tested for intradermal injections and for topical application: 100, 50, 25, 12.5, 6.25 and 3.125% in olive oil.

In the main experiment, the induction phase for the test group consisted of:

one pair of intradermal injections of test substance at 6.25% in olive oil

one pair of intradermal injections of Freund's complete adjuvant diluted 50% in physiological saline

one pair of intradermal injections of mixture of equal volumes of Freund's complete adjuvant at 50% and test substance at 12.5% in olive oil.

For control group, test substance was replaced by isotonic solution of NaCl.

Seven days later, undiluted test substance was applied topically for 48 h, followed by a rest phase of 17 days.

For the challenge phase, all animals were exposed to 25 and 12.5% of the test susbtance by topical application under occlusive conditions for 24 h. Cutaneous reactions were recorded 24 and 48 h after the removal of the test substance.

Hexylcinnamicaldehyde and mercaptobenzothiazole were used as positive controls and induced positive sensitization responses in test animals.

No cutaneous reactions following the removal of the occlusive dressing from all animals were observed at 24 and 48 h readings.

Terpineol multiconstituent can be considered as a non sensitiser and should not be classified according to CLP Regulation (EC) No 1272/2008.

Reference 2

Endpoint:

skin sensitisation

Remarks:

in vivo

Type of information:

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

Adequacy of study:

supporting study

Justification for type of information:

Alpha-terpineol is one of the main constituents of multiconstituent substance TERPINEOL MULTICONSTITUENT. Therefore, data on alpha-terpineol can be used for extrapolation to TERPINEOL MULTICONSTITUENT.

Reason / purpose for cross-reference:

read-across source

Table 1: Primary PLNA responses

 

		Negative controls	Vehicle		Chlorpromazine
	Terpineol	Barbital	DMSO	Saline	0.5 mg/paw	2.5 mg/paw	5.0 mg/paw
N	10	8	47	50	4	6	11
WI	1.32 ± 0.71	1.06 ± 0.36	1.48 ± 0.65	1.12 ± 0.90	1.30 ± 0.35	2.06 ± 0.81*	3.22 ± 1.13*
CI	2.00 ± 3.32	1.34 ± 0.92	2.95 ± 3.68	2.04 ± 2.03	1.26 ± 0.81	8.49 ± 8.91*	8.28 ± 8.19*
IPR, no. (%)	2 (20)	0 (0)	5 (10.6)	3 (6)	0.0	50.0	63.6*

* indicates that the value differs from that of the lowest dose group (0.5 mg/paw)

- Injected doses were 5 mg/paw (monoterpenes and barbital) or 50 µL /paw (vehicles).

- Values are means ± SD;

- Weight (WI) and Cellularity (CI) indices: values for the draining popliteal lymph node of the treated (right paw) side divided by that of the control (left paw) side.

- IPR, number (%) of rats within the group with WI ≥ 2 and CI ≥ 5.

- Substances were classified as negative because group mean values for WI and CI were lower than 2 and 5, respectively.

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

alpha-Terpineol was not considered as a sensitiser.

Executive summary:

In a popliteal lymph node assay (PLNA), a group of 10 female Wistar rats were injected subcutaneously with alpha-terpineol at 5 mg/paw into the right hind footpad while the contralateral footpad was injected with the vehicle (DMSO) alone. Chlorpromazine (CPZ) and barbital were used as positive and negative controls, respectively. Weight (WI) and cellularity (CI) indices for draining PLNs were determined 7 days after treatment. 

Weight (WI) and cellularity (CI) indices for alpha terpineol was determined to be 1.32 ± 0.71 and 2.00 ± 3.32, respectively. alpha-Terpineol was classified as negative because group mean values for WI and CI were lower than 2 and 5, respectively.

Therefore, alpha-terpineol was not considered as a sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

In a skin sensitisation study conducted according to OECD guideline 406, guinea-pigs were induced with intradermal injections of terpineol multiconstituent at 12.5% and 6.25% in olive oil and 7 days later by topical application of terpineol multiconstituent undiluted. They were then challenged at 12.5 and 25%. None of the animals showed any sign of positive reaction. In a popliteal lymph node assay where alpha-terpineol was injected subcutaneously at 5 mg/paw in rats, weight and cellularity indices for draining popliteal lymph nodes determined 7 days after treatment did not show any sign of sensitisation reaction.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Terpineol multiconstituent was not identified as a skin sensitiser in an OECD 406 study and alpha-terpineol did not show any sign of sensitisation in a popliteal lymph node assay in rats. Therefore, tepineol multiconstituent is not classified as skin sensitiser according to CLP Regulation (EC) No 1272 /2008.