Magnesium

Dermal absorption

Administrative data

Endpoint:

dermal absorption in vitro / ex vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Study period:

no data available

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented and scientifically acceptable.

Data source

Reference

Reference Type:

publication

Title:

Permeabilty of human skin to selected anions and cations - in vitro studies.

Author:

Laudanska, H.; et al.

Year:

2002

Bibliographic source:

Res. Communications Molecular Pathol. Pharmacol., 16-26

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Estimation whether magnesium ions (Mg2+) are able to pass through isolated patches of human skin and investigation of the dynamics of ion diffusion.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Magnesium sulphate

EC Number:

231-298-2

EC Name:

Magnesium sulphate

IUPAC Name:

231-298-2

Constituent 2

Reference substance name:

10034-99-8

Cas Number:

10034-99-8

IUPAC Name:

10034-99-8

Constituent 3

Reference substance name:

magnesium sulfate heptahydrate

IUPAC Name:

magnesium sulfate heptahydrate

Test material form:

other: solid

Details on test material:

- Name of test material (as cited in study report): magnesium sulfate heptahydrate
- Physical state: solid

Radiolabelling:

no

Test animals

Species:

human

Strain:

other: not applicable, human tissue

Sex:

not specified

Details on test animals or test system and environmental conditions:

not applicable, since no test animals were used

Administration / exposure

Type of coverage:

other: in solution

Vehicle:

physiological saline

Duration of exposure:

20 hours at 37 °C for each experiment.

Doses:

Concentrations of 0.3 and 2.1 mg Mg2+/L were tested

No. of animals per group:

not applicable

Control animals:

no

Remarks:

not applicable

Details on study design:

DOSE PREPARATION
no data

APPLICATION OF DOSE:
in solution

VEHICLE
no further details as described in the field "Vehicle"

TEST SITE
not applicable

SITE PROTECTION / USE OF RESTRAINERS FOR PREVENTING INGESTION: no (not applicable)

REMOVAL OF TEST SUBSTANCE
not applicable

SAMPLE COLLECTION
not applicable

SAMPLE PREPARATION
- Storage procedure: Samples were frozen in -20°C and stored for discriminations.
- Preparation details: no data

ANALYSIS
Ion chromatography method was used to determine cation and anion levels. Ion chromatograph Metrohm operated with Metrodata 714 IC version 2.06 software equipped with Super SEP anionic and cationic columns was applied.

OTHER:
no further details

Details on in vitro test system (if applicable):

SKIN PREPARATION
- Source of skin: Human skin samples from mammectomised breasts of 27 breast cancer patients, aged 34 to 55 years.
- Ethical approval if human skin: The study was approved by University Ethic Committee.
- Preparative technique: A dermatome was used to sample the skin in all cases.
- Thickness of skin (in mm): 0.5
- Storage conditions: Skin samples were transported in ice-cold saline and frozen (-20 °C) until used in the experiments. Storage did not exceed 3 weeks.

PRINCIPLES OF ASSAY
- Diffusion cell: Each of 3 systems consisted of dual (transmission and reception chamber of 20 mL volume, respectively) diffusion chambers. A fraction collector and a peristaltic pump were attached to each system.
- Receptor fluid: Isotonic saline solution.
- Test temperature: 37 °C
- Other: For each of the ions, 5 to 8 experiments were performed resulting in a total of 27 experiments; samples for analysis were taken at 60-minute intervals.

Results and discussion

Signs and symptoms of toxicity:

not specified

Dermal irritation:

not specified

Absorption in different matrices:

not applicable

Total recovery:

no data

Percutaneous absorption

Remarks on result:

other: not determined

Conversion factor human vs. animal skin:

not examined

Any other information on results incl. tables

The aim of the study was to estimate whether magnesium is able to pass trroug isolated patches of huma skin and to investigate the dynamics of ion diffusion.

Applicant's summary and conclusion

Conclusions:

Human skin is permeable to magnesium at concentrations comparable to those found in rainwater from Polish regions with different levels of air pollution. However, specific dermal dermal absorption rates cannot be derived from the parameters reported.