Diundecyl phthalate, branched and linear

Dermal absorption

Administrative data

Endpoint:

dermal absorption

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

supporting study

Study period:

October 28, 2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Estimation method using accepted and valid (Q)SAR method.

Data source

Reference

Reference 1

Reference Type:

other: software

Title:

Unnamed

Year:

2011

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Guideline:

other: ECHA Guidance on information requirements and chemical safety assessment - Chapter R.06: QSARs and grouping of chemicals - May 2008

Principles of method if other than guideline:

The rate of mass build-up (or loss) on the skin comes from the deposition rate onto the skin minus the absorption rate into the Stratum Corneum (SC) and the amount evaporating from the skin to the air.

IH Skin Perm provides two primary dermal exposure modes to the modeler. The first is “instantaneous deposition” in which the substance is assumed to be on the skin as the result of a single exposure event. The second is “deposition over time” in which the substance is assumed to be applied at a constant rate over time. In the first case (instantaneous deposition) the above DepositionRate is zero and IH Skin Perm then works to keep track of this single dose over time as it is absorbed into the SC or evaporates from the surface of the skin. In the second case (deposition over time) the rate of the substance going to the skin is assumed constant and the thickness of the film on the skin will either increase or decrease with time depending on the relative rates of deposition and removal.

The user inputs the amount going onto the skin as a single dose or as a constant rate and IH SkinPerm calculates the amount of chemical absorbed into the SC over time until all the material disappears from the surface via absorption and evaporation or the exposure is considered to be over.
Ultimately, the program estimates the amount of chemical absorbed into the systemic circulation of the body using clearly defined assumptions.
IH SkinPerm does all of this using relatively few physical chemical inputs for the substance. The details of these calculations are all available from Dr. ten Berge (ref: specific documents (http://home.planet.nl/~wtberge/qsarperm.html).

Test material

Test material information

Constituent 1

Reference substance name:

Diundecyl phthalate, branched and linear

EC Number:

287-401-6

EC Name:

Diundecyl phthalate, branched and linear

Cas Number:

85507-79-5

Molecular formula:

C30H50O4

IUPAC Name:

2-benzofuran-1,3-dione, esterification products with Undecanol, branched and linear

Details on test material:

- SMILES notation (*): O=C(c1ccccc1C(=O)OCCCCCCCCCCC)OCC(CCCCCCC)C

- Vapour Pressure: 0.0377 Pa
- Water solubility: 0.000033 mg/L
- Log Kow (skin, pH= 5.5): 9.74
- Density: 952.7 mg/cm3

(*) SMILES notation is indicative of the most representative component of the UVCB substance

Results and discussion

Percutaneous absorption

Dose:

4573

Parameter:

percentage

Absorption:

ca. 0 %

Remarks on result:

other: 4 h

Any other information on results incl. tables

DATA INPUT

Substance

IUPAC name:2-benzofuran-1,3-dione, esterification products with Undecanol, branched and linear

CAS number: not available

Molecular weight: 474.73

Temperature: 25 °C

Vapour Pressure: 0.0377 Pa

Water solubility: 0.000033 mg/L

Log Kow (skin, pH= 5.5): 9.74

Density: 952.7 mg/cm3

 

Scenario parameters

Instantaneous deposition

·        Deposition dose^*: 4573 mg

·        Affected skin area^**: 1000 cm²

·        Thickness of stagnant air^***: 1 cm

 

Timing parameters

·        Start deposition: 0 hr

·        End time observation: 4 hr

 

Report parameters

·        Calculationintervals/hours: 6000

·        Report intervals/hours: 600

 

 

^*Approximately 2 mL of a liquid having a viscosity similar to water will practically wet the palms of two hands (ca. 420cm²). So 4.8 mL will wet all the skin surface of both hands. Ii is reasonably expected more liquid will be excess and wash/fall off.

 

^**Estimated skin surface of two hands of an adult.

 

^***Nude skin.

RESULTS

Deposition: Instantaneous

Tot. Deposition: 4573 mg

 

Fraction absorbed: 0.0%

Amount absorbed: 0.0052 mg

Lag time stratum corneum: 11.3 min.

 

Max. derm. abs.: 6.00E-07 mg/cm²/hr

Max. derm. abs. for 2000 cm²in 1 hour (from liquid): 0.0013 mg

 

Dermal/Respiratory uptake ratio (from airborne vapour): R= 0.0017

 

R= RX/X

 

RX: total dermal absorption by dermal exposure to airborne vapour

X:  total inhalation absorption from airborne vapour

 

Assuming that Fully Respiratory Protection provides 100% efficiency:

 

Protection from respirator= 100*X/(RX+X)= 100/(R+1)= 100/1.0017= 99.8% protection against overexposure to the substance in the form of vapour due to dermal vapour absorption over whole body surface.

Applicant's summary and conclusion

Executive summary:

The dermal absorption of diundecyl phthalate, branched and linear (DIPLAST L 11) leads to the following results, obtained using the SkinPerm v1.15 model according to the input data:

Deposition: Instantaneous

Tot. Deposition: 4573 mg

 

Fraction absorbed: 0.0%

Amount absorbed: 0.0052 mg

Lag time stratum corneum: 11.3 min.

 

Max. derm. abs.: 6.00E-07 mg/cm²/hr

Max. derm. abs. for 2000 cm²in 1 hour (from liquid): 0.0013 mg

 

Dermal/Respiratory uptake ratio (from airborne vapour): R= 0.0017