Magnesium glycerophosphate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27 September 2017 until 03 November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: according to OECD 439 Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: UN GHS (2003, last rev. 2009)

Principles of method if other than guideline:

• Based on a “Statement on the Scientific Validity of In Vitro Tests for Skin Irritation” of the European Commission (November 2008), official acceptance of the test method in the EU was achieved and implemented in EU, 2008a, Council Regulation (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to EC Regulation No 1907/2006 of the European Parliament and of the Council on REACH; 1st ATP 2009: EC Regulation No 761/2009 of 23 July 2009 amending, for the purpose of its ATP, EC Regulation No 440/2008 laying down test methods pursuant to EC Regulation No 1907/2006 of the European Parliament and of the Council on REACH, section B46.

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection: 13-16 July 2015, Date of Signature: 14 September 2015

Test material

Test material information

Constituent 1

Reference substance name:

Magnesium glycerophosphate

EC Number:

213-149-3

EC Name:

Magnesium glycerophosphate

Cas Number:

927-20-8

Molecular formula:

C3H9O6P.Mg

IUPAC Name:

magnesium glycerophosphate

Test material form:

solid: particulate/powder

Details on test material:

Batch: INVG003917

Specific details on test material used for the study:

Information as provided by the Sponsor.
Identification: Magnesium glycerophosphate
CAS No.: 927-20-8
Batch: INVG003917
Purity: 96.5% (w/w) (calculated) dose calculation was not adjusted to purity
Expiry Date: 10 June 2021
Appearance: White powder
Storage Conditions: At room temperature, protected from light and moisture*
Stability in Solvent: Stable in water (not quantified)
Safety Precautions: Routine hygienic procedures will be sufficient to ensure personnel health and safety. For further information see Material Safety Data Sheet.
* only valid for storage conditions, not for test performance

In vitro test system

Test system:

human skin model

Remarks:

reconstituted human epidermis model

Vehicle:

other: DPBS

Remarks:

aqueous phosphate buffer

Control samples:

yes, concurrent vehicle

Amount/concentration applied:

Each approximately 25 mg (~ 39 mg/cm2 according to guideline) of the test item were applied to the tissues, wetted with 25 µL of DPBS, and spread to match the surface of the tissue for a complete treatment time of 60 minutes.

Duration of treatment / exposure:

60 minutes

Number of replicates:

Each three tissues of the human skin model EpiDerm™ were treated with the test item, the negative and the positive control for 60 minutes.
Approximately 25 mg of the test item were applied to each tissue, wetted with 25 µL of DPBS, and spread to match the surface of triplicate tissue.

30 µL of either the negative control (DPBS) or the positive control (5% SLS) were applied to triplicate tissue each.
The test item and the positive and negative controls were washed off the skin tissues after 60 minutes treatment. After further incubation for about 43 hours the tissues were treated with the MTT solution for 3 hours following 69.75 hours extraction of the colorant from the cells. The amount of extracted colorant was determined photometrically at 570 nm.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean of 3

Value:

99.7

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

Results after treatment with Magnesium glycerophosphate and the controls

Treatment Group	Tissue No.	OD 570 nm Well 1	OD 570 nm Well 2	OD 570 nm Well 3	Mean OD of 3 Wells	Mean OD of 3 Wells blank corrected	Mean OD of 3 tissues blank corrected	Rel. Viability [%] Tissue 1, 2 + 3*	Relative Standard Deviation [%]	Mean Rel. Viability [%]**
Blank		0.037	0.037	0.037	0.037
Negative Control	1	1.447	1.438	1.444	1.443	1.406	1.431	98.2	1.6	100.0
	2	1.468	1.481	1.469	1.473	1.436		100.3
	3	1.452	1.499	1.514	1.488	1.451		101.4
Positive Control	1	0.104	0.103	0.103	0.104	0.067	0.067	4.7	1.1	4.7
	2	0.105	0.104	0.104	0.104	0.067		4.7
	3	0.104	0.106	0.105	0.105	0.068		4.8
Test Item	1	1.469	1.468	1.476	1.471	1.434	1.427	100.2	2.1	99.7
	2	1.440	1.429	1.422	1.431	1.393		97.4
	3	1.474	1.499	1.498	1.490	1.453		101.6

 

*       Mean of three replicate wells after blank correction

**       relative absorbance per tissue [rounded values]

***     relative absorbance per treatment group [rounded values]

 

  The optical pre-experiment (colour interference pre-experiment) to investigate the test item’scolour change potential in water did not lead to a change in colour.

Optical evaluation of the MTT-reducing capacity of the test item after 1 hour incubation withMTT-reagent did not show blue/purple colour.

The mean relative absorbance value of the test item, corresponding to the cell viability,decreased to 99.7% (threshold for irritancy:≤50%), consequently the test item was not irritant to skin.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

Under the experimental conditions (in vitro skin model) reported, Magnesium glycerophosphate is not irritant to skin according to UN GHS and EU CLP regulation.

Executive summary:

This in vitro study was performed to assess the irritation potential of Magnesium glycerophosphate by means of the Human Skin Model Test.

The test item passed the MTT- and the Colour Interference pre-tests.

The test item, the negative control (DPBS), and the positive control (5% SLS) were applied to triplicate tissue each.

The test item and the positive and negative controls were washed off the skin tissues after 60minutes treatment. After further incubation forabout 41.5 hours the tissues were treated with the MTT solution for 3 hours following 2.5hours extraction of the colorant from the cells. The amount of extracted colorant was determined photometrically at 570 nm.

After treatment with the negative control the absorbance values were well within the required acceptability criterion of mean OD³0.8 and ≤ 2.8 for the 60 minutes treatment interval thus showing the quality of the tissues.

Treatment with the positive control induced a decrease in the relative absorbance comparedwith the negative control to 4.7% thus ensuring the validity of the test system.

The relative standard deviations between the % variability values of the test item, the positiveand negative controls in the main test were below 10% (threshold of the "OECD Guidelinefor the Testing of Chemicals 439:In vitro Skin Irritation: Reconstructed Human Epidermis Test Method”: < 18%), thus ensuring the validity of the study.

Compared to the relative absorbance value of the negative controlthe mean relativeabsorbance value was reduced to 99.7% after exposure of the skin tissues to the test item. This value is above the threshold for irritancy of ≤ 50%. Therefore, the test item is not considered to possess an irritant potential.