Formaldehyde

Dermal absorption

Administrative data

Endpoint:

dermal absorption in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

validity restricted due to the use of high concentration inducing local toxic effects (corrosion at the high dose level) and exclusion of radioactivity in deeper skin layers for calculation of absorption (underestimation of absorption rate at low dose).

Data source

Reference

Reference Type:

publication

Title:

The in vitro permeability of human skin to benzene, ethylene glycol, formaldehyde, and n-Hexane

Author:

Loden M

Year:

1986

Bibliographic source:

Acta Pharmacol Toxicol 58: 382-389

Materials and methods

Test guideline

Qualifier:

equivalent or similar to

Guideline:

OECD Guideline 428 (Skin Absorption: In Vitro Method)

Deviations:

no

GLP compliance:

not specified

Test material

Reference

Name:

Unnamed

Type:

Constituent

Radiolabelling:

yes

Remarks:

14C-formaldehyde

Test animals

Species:

human

Administration / exposure

Type of coverage:

not specified

Vehicle:

water

Duration of exposure:

15 h

Doses:

no data
concentration: 3.7% or 37%

No. of animals per group:

5 trials with skin samples for each concentration

Details on in vitro test system (if applicable):

Permeability of human skin to 14C-formaldehyde studied using excised full skin in a flow-through (5 mL/h) diffusion cell at 30°C. Radioactivity measured by scintillation counting. Resorption related to radioactivity in receptor fluid (radioactivity in skin not included) although radioactivity in tangential cryo-slices of the skin (thickness: 2 mm) was measured after 0.5 or 15 hours of exposure.

Results and discussion

Signs and symptoms of toxicity:

not specified

Dermal irritation:

not specified

Absorption in different matrices:

The dermal absorption was 16.7 µg/cm²/h using 3.7% formalin and 319 µg/cm²/h using 37% formalin (local corrosive effects assumed). Exclusion of radioactivity in deeper skin layers for calculation of absorption.

Total recovery:

no data

Applicant's summary and conclusion

Executive summary:

Comparable to Guideline study; validity restricted due to the use of high concentration inducing local toxic effects (corrosion at the high dose level) and exclusion of radioactivity in deeper skin layers for calculation of absorption (underestimation of absorption rate at low dose).

Permeability of human skin to 14C-formaldehyde studied using excised full skin in a flow-through (5 mL/h) diffusion cell at 30°C. The dermal absorption was 16.7 µg/cm²/h using 3.7% formalin and 319 µg/cm²/h using 37% formalin.