Dibutyl hydrogen phosphate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD TG 431

Principles of method if other than guideline:

The experiment was carried out on a reconstructed human epidermis EST-1000 (CeIlSystems, St. Katharinen, Germany).

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dibutyl hydrogen phosphate

EC Number:

203-509-8

EC Name:

Dibutyl hydrogen phosphate

Cas Number:

107-66-4

Molecular formula:

C8H19O4P

IUPAC Name:

dibutyl hydrogen phosphate

In vitro test system

Test system:

human skin model

Remarks:

EST-1000 (Cell Systems, St. Katharinen, Germany)

Source species:

human

Cell type:

other: reconstructed 3D human epidermis

Vehicle:

unchanged (no vehicle)

Amount/concentration applied:

50 mL of the neat liquid test item

Duration of treatment / exposure:

incubation periods of 3 min and 60 min

Duration of post-treatment incubation (if applicable):

no post-treatment incubation period; 3 hours incubation with MRR solution

Number of replicates:

3

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Remarks:

3 min treatment

Value:

64.38

Negative controls validity:

valid

Remarks on result:

other: mean of 3 samples compared to negative control (NaCl, 0.9%, set to 100% viability)

Results 2

Irritation / corrosion parameter:

% tissue viability

Remarks:

60 min treatment

Value:

1.79

Negative controls validity:

valid

Remarks on result:

other: mean of 3 samples compared to negative control (0.9% NaCl, set to 100% viability)

Any other information on results incl. tables

Compound                                   [%] Cell viability 3 min       [%] Cell viability 60 min       Classification*

test item                                                  64.36                                  1.79                            Corrosive                   

Negative control                                   100                                   100                                Negative control

* Classification was done in accordance with the existing guideline and internationally accepted protocols, i.e. evaluation of LD50 values after 3 min. and/or less than 15% viability after a 60 min. incubation period.

Substances are classified as "corrosive (R34)", if the cell viability of the EST 1000 is decreased by more than 50% after 3 min. of incubation to the test item, or if the cell viability is less than 15% after 60 min. of exposure to the test item.

Applicant's summary and conclusion

Interpretation of results:

Category 1B (corrosive) based on GHS criteria

Executive summary:

A study for predicting non-specific, corrosive potentials of compounds by using reconstructed human skin (RHS) was performed. The experiment was carried out on a reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany) for detection of topically applied skin corrosives with the test item dibutyl hydrogen phosphate.

Corrosive skin effects of substances are defined as irreversible damage of skin; namely, visible necrosis through the epidermis and into the dermis, following the application of a test substance for up to four hours. In vivo corrosive reactions are typified by ulcers, bleeding, and bloody scabs.

A 100% concentration was tested on the skin/epidermal equivalents in triplets. For the determination of time related cytotoxic effects the incubation periods were 3 min. and 60 min., respectively. By this the study, was conducted in accordance with the OECD 431 guideline using the test item concentrations and incubation periods recommended there. These tests are also related to the revised OECD 404 guideline "Acute Dermal Irritation/Corrosion".

The test item was applied at a 100% concentration, i.e. 50µl per insert.

The MTT (Methylthiazoletetrazolium) method has determined the following values of viability after 3 min. or after 60 min. of incubation: 64% and 2% (rounded), respectively.

Thus, the results show that a corrosive property of the test item was determined by the assay used.