Iron citrate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Iron citrate

EC Number:

219-045-4

EC Name:

Iron citrate

Cas Number:

2338-05-8

Molecular formula:

C6H8O7.xFe

IUPAC Name:

iron citrate

Specific details on test material used for the study:

Name Ferric citrate monohydrate
Batch no. 45882
Appearance red to brown solid powder
Composition Ferric Citrate
Purity 99.81%
Homogeneity homogeneous
Expiry date 18. May 2019
Storage Room Temperature (20 ± 5 °C); Keep away from light

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: The EpiDermTM tissue consists of human-derived epidermal keratinocytes which have been cultured to form a multi-layered, highly differentiated model of the human epidermis. The EpiDermTM tissues are cultured on specially prepared cell culture inserts.

Vehicle:

unchanged (no vehicle)

Details on test system:

The tissues were wetted with 25 μL DPBS buffer before applying the test item and spreading it to match the tissue size.
The following amounts were applied to the three tissues:
1 = 24.9 mg
2 = 25.6 mg
3 = 25.6 mg

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

Circa 25 mg on each tissue

Duration of treatment / exposure:

After dosing the last tissue, all plates were transferred into the incubator for 35 minutes at 37 ± 1°C and 5.0 ± 1% CO2 and ≥ 95% relative humidity.
1 hour after the first application, the inserts were removed from the plates using sterile forceps and rinsed immediately in 1-minute-intervals.

Duration of post-treatment incubation (if applicable):

After rinsing thoroughly with DPBS, each tissue was blotted with sterile cellulose tissue and then transferred into a new 6-well-plate with fresh assay medium (0.9 mL). The surface of the inserts was then carefully dried with a sterile cotton tipped swab.Then, the tissues were set in the incubator for 26 hours at 32 ± 1°C and 3.0 ± 1% CO2 and ≥ 95% relative humidity.

Number of replicates:

three

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean of three tests

Value:

91

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

The test item Ferric citrate monohydrate is considered as non- irritant to skin.
After the treatment, the mean value of relative tissue viability was reduced to 91.0%. This value is above the threshold for skin irritation (50%).
The optical density of the negative control was well within the required acceptability criterion of 0.8 ≤ mean OD ≤ 2.8.
The positive control has met the acceptance criterion too, for thus ensuring the validity of the test system.
Variation within replicates was within the accepted range for negative control, positive con-trol and test item (required: ≤ 18%).
For these reasons, the result of the test is considered valid.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

After the treatment with the test item, the mean value of relative tissue viability was reduced to 91.0 %. This value is above the threshold for skin irritation potential (50%). Test items that induce values above the threshold of 50% are considered non- irritant to skin.
Therefore, the test item Ferric citrate monohydrate is considered non- irritant to skin in the Reconstructed human Epidermis (RhE) Test Method.