2-(2-butoxyethoxy)ethyl 6-propylpiperonyl ether

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPP 81-6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

Although nowadays in many member states of the EU the protocol byMagnusson and Kligmanis the preferred method, the Buehler test is a valid method according to OECD 406.
At the time of study conduction no such preference existed. The GPMT method was not preferred over the Buehler Test.
The Buehler test method has demonstrated its ability over the years to detect chemicals even with weak potential to sensitize human skin (Basketter DA, Gerberick GF. An interlaboratory evaluation of the Buehler test for the identification and classification of skin sensitizers. Contact Dermatitis. 35(3):146-51. 1996).
Thus, the Buehler test is a valid and reliable study to determine the skin sensitizing potency of PBO.
In the light of animal welfare a sensitization test according to the GPMT protocol was not conducted while a Buehler test was available

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-butoxyethoxy)ethyl 6-propylpiperonyl ether

EC Number:

200-076-7

EC Name:

2-(2-butoxyethoxy)ethyl 6-propylpiperonyl ether

Cas Number:

51-03-6

Molecular formula:

C19H30O5

IUPAC Name:

2-(2-butoxyethoxy)ethyl 6-propylpiperonyl ether

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male

Details on test animals and environmental conditions:

Source Davidson Mill Farm, Gamesbourg, NJ 08831, USA
Age/weight at study initiation 356 - 415 g
Number of animals per group 10 animals (Modified Buehler test)
Control animals 10 animals

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Remarks:

none

Induction 2

Concentration / amount:

0.4mL

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Remarks:

none

Challenge 2

Concentration / amount:

0.4mL

No. of animals per dose:

10

Positive control substance(s):

yes

Remarks:

1-Chloro-2,4-dinitrobenzene (Eastman Kodak Co., Rochester, NY), as a 0.1% w/v dilution in 50% ethanol: 0.9 % saline solution

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.4 mL

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Results 2

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.4 ml

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Results 3

Reading:

1st reading

Hours after challenge:

1

Group:

positive control

Dose level:

0.1% w/v dilution in 50% ethanol: 0.9% saline solution

No. with + reactions:

10

Total no. in group:

10

Clinical observations:

Erythema, Edema

Remarks on result:

positive indication of skin sensitisation

Results 4

Reading:

2nd reading

Hours after challenge:

24

Group:

positive control

Dose level:

0.1% w/v dilution in 50% ethanol: 0.9% saline solution

No. with + reactions:

10

Total no. in group:

10

Clinical observations:

Erythema

Remarks on result:

positive indication of skin sensitisation

Results 5

Group:

negative control

Remarks on result:

not measured/tested

Any other information on results incl. tables

Results of pilot studies:  

Prior to the main test, the test article was screened as supplied at concentrations of 75% v/v, 50% v/v and 25% v/v in corn oil (Mazola corn oil, Best Foods, CPC International Inc., Englewood cliffs, NJ 07632) to determine its minimal irritation threshold and its highest non-irritating concentration. After a 6-hour skin contact period, the test article at all levels produced no skin irritation.

1.1              Results of test
1.1.1         24h after challenge	All animals showed neither edema nor erythema 24 hours after termination of challenge
1.1.2         48h after challenge	All animals showed neither edema nor erythema 48 hours after termination of challenge
1.1.3         Other findings	The group of naive guinea pigs served as irritation controls also showed no effects.

-sensitization reaction: the test substance did not show any reactions at  any interval. 
Therefore, it is not a dermal sensitizer.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The naive positive control animals were negative at challenge. For the DNCB positive control sensitisation was demonstrated.
Although in the group treated with Piperonyl Butoxide there were scattered 1+ readings during the induction applications in the 10 test guinea pigs, the challenge application was completely negative. The naïve controls were all negative.
Piperonyl Butoxide has no sensitizing potential under the conditions of the Modified Buehler Test. Skin sensitization was not provoked following the challenge phase.
The test article administered dermally as supplied doesn’t appear to be a dermal sensitizer to albino guinea pigs, under the study conditions utilized.