Formaldehyde

Repeated dose toxicity: dermal

Administrative data

Endpoint:

repeated dose toxicity: dermal

Remarks:

other: skin initiation/promotion study

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Data from skin initiation/promotion studies; limited documentation of formaldehyde (only) induced skin irritation (no details about skin painting; microscopy of skin lesion after 1% solution not described; no vehicle controls)

Data source

Reference

Reference Type:

publication

Title:

Formaldehyde and skin carcinigenesis

Author:

Iversen OH

Year:

1986

Bibliographic source:

Environ Int 12: 541-544

Materials and methods

Principles of method if other than guideline:

skin initiation/promotion study in mice; also examination of local effects of formaldehyde without co-exposure

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Formaldehyde

EC Number:

200-001-8

EC Name:

Formaldehyde

Cas Number:

50-00-0

Molecular formula:

CH2O

IUPAC Name:

formaldehyde

Details on test material:

- Name of test material (as cited in study report): formaldehyde

Specific details on test material used for the study:

technical grade formaldehyde;
40% formalin diluted

Test animals

Species:

mouse

Strain:

other: hairless (hr/hr, Oslo)

Sex:

male/female

Administration / exposure

Type of coverage:

open

Vehicle:

water

Details on exposure:

topical application of 200 µL 1% or 10% formaldehyde solution (no further details including site of application on the back)

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

60 weeks

Frequency of treatment:

twice a week

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

1 other: %

Remarks:

200 µL of 1% solution (2 mg/animal/application); nominal per unit area

Doses / concentrations 2

Dose / conc.:

10 other: %

Remarks:

200 µL of 10% solution (20 mg/animal/application); nominal per unit area

No. of animals per sex per dose:

16

Control animals:

no

Details on study design:

Post-exposure period: none

Examinations

Observations and examinations performed and frequency:

Macroscopical and microscopical examination of the skin (no details concerning the low dose group)

Sacrifice and pathology:

Complete autopsy and histopathology was performed in mice of the 10% group (including nasal cavity).

Results and discussion

Results of examinations

Details on results:

No treatment related lesions were detected at 1% formaldehyde (in accord with data on irritation in Section 7.3.1). Slight hyperplasia of the epidermis was found in animals of the 10% group and a few mice had small ulcers and scratches of the skin (no further details). No other treatment related effects occurred at histopathological examination of other organs (although slight inhalation exposure was present via evaporation of the test substance).

Effect levels

Dose descriptor:

LOEL

Effect level:

1 other: % Formaldehyde

Sex:

male/female

Basis for effect level:

other: No treatment related lesions found. For effects at higher dose levels see "details on results".

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

The NOAEC for skin effects in mice was 200 µL of 1% formaldehyde applied twice weekly for 60 weeks; at a concentration of 10% hyperplasia of the epidermis was found a few mice had small ulcers and scratches of the skin. However, the documentation was limited.