Reaction mass of methyl 2-methylbenzene-1-sulfonate and methyl toluene-4-sulphonate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented study which meets basic scientific principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1960

Report date:

1960

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The skin sensitisation study in experimental animals was already performed in the 1960s. Therefore it is not conducted in accordance with the rules of Good Laboratory Practice (GLP) and internationally-agreed guidelines (e.g. OECD guideline No. 406), but using good scientific practices at that time.
BASF-Test, see details in remarks on material and methods.

GLP compliance:

no

Type of study:

other: a kind of Buehler test: induction and challenge with topical application

Justification for non-LLNA method:

The LLNA has not yet been invented.

Test material

Test material information

Constituent 1

Reference substance name:

methyl 2-methylbenzene-1-sulfonate

Cas Number:

23373-38-8

Molecular formula:

C8H10O3S

IUPAC Name:

methyl 2-methylbenzene-1-sulfonate

Constituent 2

Reference substance name:

Methyl toluene-4-sulphonate

EC Number:

201-283-5

EC Name:

Methyl toluene-4-sulphonate

Cas Number:

80-48-8

Molecular formula:

C8H10O3S

IUPAC Name:

methyl 4-methylbenzene-1-sulfonate

Test material form:

liquid

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

not specified

Details on test animals and environmental conditions:

No information available

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

other: ether

Concentration / amount:

10 %

Day(s)/duration:

The same application as on day 0 is carried out on the same test area daily over 8 days (= 9 treatments)

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

Challenge

Route:

epicutaneous, open

Vehicle:

other: ether

Concentration / amount:

1 %

Day(s)/duration:

once/8, 12 and 24 h after application skin reactions were observed

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

5 (test group); 5 (control group)

Details on study design:

INDUCTION (topical with regard to test substance treated and control group):

The left and right flanks of the guinea pigs were shorn (ca. 25 cm²) one day prior to the application.
The test substance in a suitable vehicle was applied by wiping the shaved skin of the left flank with a soaked cotton pad three times one after another. The same application as on day 0 was carried out on the same test area of the same flank on the following days until a significant skin irritation is observed.
The vehicle only is applied once in a similar manner to that used for the treated group in the control group.

CHALLENGE (topical with regard to test substance treated and control group):

Ca. one week (8-10 days) after the last application of the induction phase the left and right flanks of the guinea pigs were shorn again. Approximately 24 hours later the test substance, at a non-irritant concentration (a tenth of the concentration used for induction) was once applied to untreated right flank of treated animals. 8, 12 and 24 hours later the skin reactions are observed and recorded

Challenge controls:

see "Details on study design"

Positive control substance(s):

not specified

Results and discussion

Positive control results:

not applicable

In vivo (non-LLNA)

Results

Reading:

other: single result is recorded across the three reading times (8, 12, 24 hours)

Hours after challenge:

8

Group:

test chemical

Dose level:

1 % test substance formulation

No. with + reactions:

5

Total no. in group:

5

Clinical observations:

none

Remarks on result:

positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

other: sensitising

Executive summary:

In a guinea pig study already performed in the 1960s the test substance (formulated in ether) revealed a skin sensitizing potential at a challenge concentration of 1 %.