Reaction mass of bis(N-decyl-N,N-dimethyldecan-1-aminium) carbonate and N-decyl-N,N-dimethyldecan-1-aminium hydrogen carbonate

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:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

- Reliability: GLP study according to EU- and/or OECD-guidelines - Read-across justification: As both source (Didecyldimethylammonium chloride, DDAC) and target chemicals (Didecyldimethylammonium carbonate, DDA carbonate) have identical organic cations with hydrophobic side chains - the only difference is the inorganic anion carbonate or chloride with negligible contribution to the hazard properties- both substances can be predicted to have similar movement and fate characteristics.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OECD draft. OECD guideline for the testing of chemicals. Skin absorption: in vitro method. Draft supplied to the OECD by ECPA: 17 December 1999.

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: OECD draft. OECD guidance document for the conduct of skin absorption studies. Draft supplied to the OECD by ECPA: 17 December 1999.

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: COLIPA. Cosmetic ingredients: guidelines for percutaneous absorption/penetration. COLIPA, Brussels, 1995.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Test material form:

liquid: viscous

Details on test material:

- Name of test material: Didecyldimethylammonium chloride (DDAC)

Radiolabelling:

yes

Remarks:

14-C

Administration / exposure

Vehicle:

water

Duration of exposure:

24 hours

Doses:

- Concentration: 1.85 %
- Application rate: 10 µL/cm
- Target dose level: 185 µg/cm

Details on in vitro test system (if applicable):

- Test system: Human dermatomed skin membranes in vitro
- Method of application: Flow through diffusion cell system
- Application media: Water
- Concentration: 1.85 %
- Receptor fluid: Tissue culture medium with ca. 4 % bovine serum albumin maintained with 5 % CO2 in O2
- Remarks: 14C-DDAC was applied in aqueous solution. Receptor fluid was collected hourly from 0-6h and every other hour from 6-24 h post-dose. At 24 h post-dose, the underside of the skin sample was washed with receptor fluid. The skin surface was washed with 2 % soap solution and dried with tissue swabs. The tissue swabs were analysed by combustion. The stratum corneum was removed by successive tape strips. These were extracted with methanol:chloroform (2:1 v/v). The non-dose site skin was collected to determine lateral diffusion through the stratum corneum. The dose site skin was divided into dermis and epidermis by heat separation, then solubilised in Soluene-350. Unabsorbed material was the sum of the skin wash, cell wash, tissue swabs, stratum corneum, cling film and epidermis. Penetration was the sum of receptor rinse and 0-24 h receptor fluid. Dermal delivery was the sum of the dermis and non-dose site skin. Total absorbed material was the sum of dermal delivery and penetration.

Results and discussion

Absorption in different matrices:

After 24 hours less than 0.1 % of the 14C-DDAC penetrated human skin. Total absorption was 2.92 %.

Total recovery:

See table 1 below.

Percutaneous absorption

Dose:

185 µg/cm

Parameter:

percentage

Absorption:

2.92 %

Remarks on result:

other: 24

Remarks:

Less than 0.1 % of the applied 14C-DDAC dose penetrated human skin. 2.92 % of the applied dose was absorbed into the skin. 96.25 % was not absorbed. The cumulative flux value was 0.11 µg equiv./cm.

Any other information on results incl. tables

Table 1: Mean % recovery after 24 hours

Commodities analysed	Mean recovery (% of applied dose)
Skin wash	44.45
Cell wash	3.38
Swab	28.14
Cling film	0.05
Stratum corneum	13.75
Epidermis (dose site)	6.49
Dermis (dose site)	2.67
Non-dose site skin	0.18
Receptor fluid	0.06
Receptor rinse	0.00
Cumulative Results
Total penetrated	0.06
Dermal delivery	2.85
Total unabsorbed	96.25
Total absorbed	2.92
Total recovery	99.16

Applicant's summary and conclusion

Conclusions:

Less than 0.1 % of the 14C-DDAC penetrated human skin. Total absorption was 2.92 %.

Executive summary:

A study was carried out according to OECD draft guideline for the testing of chemicals (1999), OECD draft guidance for the conduct of skin absorption studies (1999) and COLIPA cosmetic ingredients: guidelines for percutaneous absorption/penetration (1995) using the structural analog Didecyldimethylammonium chloride (DDAC). In view of the chemical and structural similarities (the relevant chemical part of both, DDAC and DDACarbonate, under the conditions of this test is the common quaternary ammonium cation Didecyldimethylammonium+), it is considered that the data are adequate for DDACarbonate. 14C-DDAC was applied, in an aqueous formulation, to human skin samples using a flow through diffusion cell system. Receptor fluid was collected hourly from 0-6 h and every 2 h from 6-24 h post-dose. After 24 hours the underside of the sample was washed with receptor fluid. The upper side was washed with 2 % soap solution and dried with tissue swabs. The stratum corneum was removed with tape strips. The dose site skin was separated into epidermis and dermis, then solubilised.  The non-dose site skin was collected. The amount of radioactivity in each commodity was determined. 

Less than 0.1 % of the applied 14C-DDAC dose penetrated human skin. 2.92 % of the applied dose was absorbed into the skin. 96.25 % was not absorbed. The cumulative flux value was 0.11 µg equiv/cm.