[ethylenebis[nitrilobis(methylene)]]tetrakisphosphonic acid, sodium salt

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 July 1981 - 14 August 1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: A combined irritation and sensitisation study is reported in man, which was conducted according to a scientifically acceptable principle. No mention of GLP is included in the study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Modified Shelanski Repeated Insult Patch Test

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

EDTMP-5Na

IUPAC Name:

EDTMP-5Na

Constituent 2

Reference substance name:

Pentasodium trihydrogen [ethane-1,2-diylbis[nitrilobis(methylene)]]tetrakisphosphonate

EC Number:

231-615-4

EC Name:

Pentasodium trihydrogen [ethane-1,2-diylbis[nitrilobis(methylene)]]tetrakisphosphonate

Cas Number:

7651-99-2

Molecular formula:

C6H15N2O12P4.5Na

IUPAC Name:

pentasodium trihydrogen {ethane-1,2-diylbis[nitrilobis(methylene)]}tetrakis(phosphonate)

Details on test material:

- Name of test material (as cited in study report): Dequest (R) 2046
- Physical state: Yellow liquid
- pH: 6-8

Test animals

Species:

human

Strain:

other: n/a

Details on test animals or test system and environmental conditions:

Not applicable.

Test system

Type of coverage:

occlusive

Preparation of test site:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.2ml
- Concentration (if solution): undiluted

Duration of treatment / exposure:

Repeated application, 24h at a time

Observation period:

4 weeks

Number of animals:

56 individuals started; 54 individuals completed the study.

Details on study design:

TEST SITE

- Area of exposure: the back
- Type of wrap if used: Specially prepared Parke-Davis Readi-Bandages were used for patching in this study. The treated patch was applied to designated site after application of test material on to it. The adhesive was pressed all around to assure firm contact of the test material with the skin to form a seal to retard the loss of moisture.

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 24 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

The absence of visible irritation as a result of the application indicates that the material, tested as supplied was incapable of acting as a primary irritant of the immediate type in any of the individuals under the test. The same study assessed both irritation and sensitisation and through applications 2 to 12 only solitary, minimal responses were observed in 3 individuals during this period. In view of the lack of any responses in any of the other individuals under test, the investigator believes that these responses were artifacts and attached no significance to them. The absence of visible irritation during the challenge period further confirmed that the material, tested as supplied, was incapable of acting as a primary irritant of the immediate type in any of the individuals under test.

Other effects:

None reported.

Any other information on results incl. tables

0.2 ml of the test material was applied on skin as a 100% solution.

Dequest 2046 is known to have 35.7% active salt content at pH 6 -8, and a specific gravity of 1.3 -1.36 g/ cm^3.

The pKa of the salt at pH 7.3 is estimated to be 6. The conversion factor to determine the salt to acid equivalent for mass for EDTMP-6Na salt is 0.768.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information

Conclusions:

This combined irritation and sensitisation study in man reports no irritant effects of the test material, after a single dose nor after repeated applications. The study was carried out according to a scientifically acceptable protocol.