Phosphorous acid, mixed 2,4-bis(1-methyl-1-phenylethyl)phenyl and isodecyl and 2-(1-methyl-1-phenylethyl)phenyl and 4-(1-methyl-1-phenylethyl)phenyl and phenol triesters)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Triisodecyl phosphite

EC Number:

246-998-3

EC Name:

Triisodecyl phosphite

Cas Number:

25448-25-3

Molecular formula:

C30H63O3P

IUPAC Name:

Phosphorus acid, triisodecyl ester

Test material form:

other: liquid

Details on test material:

Test material was LE164, triisodecyl phosphite, >99% purity.

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

The animals were acclimatised for a period of at least 5 days, after which animals were selected at random and given a unique number marked on their tail. At the start of the study the animals weighed in the range of 15 to 23 grams and were 8-12 weeks in age.

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

25%, 50%, 100%

No. of animals per dose:

4

Details on study design:

Five days following the first topical applications, all mice were injected via the tail vein with 250 uL of phosphate buffered saline (PBS) containing 3H-methyl thymidine (3HTdR) giving a total of 20 uCi to each mouse.

Statistics:

EC3= 20%; based on a regression analysis of the dose groups. All dose groups were positive, but there was sufficient dose-response to determine an EC3.

Results and discussion

In vivo (LLNA)

Results

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: vehicle 14023.98 25% 53667.32 50% 103195.40 100% 137149.20

Any other information on results incl. tables

Concentration	dpm/node	Test / Control Ratio
Vehicle (acetone/olive oil 4:1)	1753.00	N/A
25%	6708.42	3.83
50%	12899.43	7.36
100%	17143.65	9.78
EC3= 20%

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Test substance was postive (ratio >3) at concentrations of 25, 50, and 100%. An EC3 was determined to be 20%. The results indicated that TDP is a skin sensitiser, but not a strong skin sensitiser.

Executive summary:

TDP was test using the LLNA assay at concentrations of 25%, 50%, and 100%. It was positive at all test concentrations. The calculated EC3 value is 20.1%. The results suggest that TDP should be classified as a skin sensitiser, but not a strong skin sensitiser.