Benzophenone

Dermal absorption

Administrative data

Endpoint:

dermal absorption in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No guideline was followed but well documented scientifically defensible approach was used to conduct the study.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1990

Materials and methods

Principles of method if other than guideline:

The percutaneous absorption of benzophenone was measured in vivo in monkey. Test item was applied to a lightly clipped 1 cm 2 area of abdominal skin at a concentration of 4 µg/cm 2. The application site was washed with soap and water as described above to remove residual material. The animals were then placed in metabolism cages to continue the urine collection for an additional 4 days. The amount of absorbed compound in the urine was determined by liquid scintillation counting.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Benzophenone

EC Number:

204-337-6

EC Name:

Benzophenone

Cas Number:

119-61-9

Molecular formula:

C13H10O

IUPAC Name:

benzophenone

Details on test material:

- Name of test material (as cited in study report): Benzophenone
- Radiochemical purity (if radiolabelling): 99.9%
- Specific activity (if radiolabelling): 5.4 mCi/mmoL
- Source: Pathfinder Laboratories, St. Louis, MO, USA

Radiolabelling:

yes

Test animals

Species:

monkey

Strain:

other: rhesus

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: California Primate Centre
- Age at study initiation: 10, 14, 19 and 19 years
- Individual metabolism cages: Yes

Administration / exposure

Type of coverage:

other: open-patch and closed-patch

Vehicle:

acetone

Duration of exposure:

24 h

Doses:

4 µg/cm2

No. of animals per group:

A total of 4 animals were used.

Control animals:

no

Details on study design:

DOSE PREPARATION
- Method for preparation of dose suspensions: The radiolabelled test item was diluted with acetone.

VEHICLE
- Amount(s) applied (volume or weight with unit): 10-20 µL/cm2.

TEST SITE
- Preparation of test site: The test site was lightly clipped.
- Area of exposure: 1 cm2 of abdominal skin
- Type of cover / wrap if used: plastic wrap or glass chamber.

SITE PROTECTION / USE OF RESTRAINERS FOR PREVENTING INGESTION: Monkeys were restrained in metabolic chairs for 24 hours.

REMOVAL OF TEST SUBSTANCE
- Washing procedures and type of cleansing agent: Washed with soap and water
- Time after start of exposure: 24 hours

SAMPLE COLLECTION
- Collection of urine and faeces: Urine samples for 4 days after the 24 hour exposure period.
- Terminal procedure: No.

ANALYSIS
- Method type(s) for identification: Liquid scintillation counting
- Liquid scintillation counting results (cpm) converted to dpm as follows: The amount of absorbed compound in the urine was determined by liquid scintillation counting, and results were corrected for total absorption as above by using a parenteral correction factor obtained in separate experiments.

Results and discussion

Signs and symptoms of toxicity:

not specified

Dermal irritation:

not specified

Percutaneous absorption

Percutaneous absorption 1

Dose:

4 µg/cm2

Parameter:

percentage

Absorption:

ca. 43.8 %

Remarks on result:

other: Urine collection over 5 days; means and SD

Remarks:

Unoccluded site

Percutaneous absorption 2

Dose:

4 µg/cm2

Parameter:

percentage

Absorption:

ca. 68.7 %

Remarks on result:

other: Urine collection over 5 days; means and SD

Remarks:

Plastic wrap

Percutaneous absorption 3

Dose:

4 µg/cm2

Parameter:

percentage

Absorption:

>= 68.6 %

Remarks on result:

other: Urine collection over 5 days; means and SD

Remarks:

Glass chamber

Any other information on results incl. tables

Percutaneous absorption of Benzophenone in the monkeys:

Absorption (% of the applied dose)
	Site occluded with
Compound	Unoccluded site	Plastic wrap	Glass chamber
Benzophenone	43.8 ± 7.5	68.7 ± 6.4	68.6 ± 4.6

Applicant's summary and conclusion

Conclusions:

After dermal application of [14C]benzophenone, approximately 70% was absorbed in rhesus monkeys within 24 hours.

Executive summary:

The percutaneous absorption of benzophenone was measured in vivo in monkey. Test item was applied to a lightly clipped 1 cm 2 area of abdominal skin at a concentration of 4 µg/cm 2. The application site was washed with soap and water as described above to remove residual material. The animals were then placed in metabolism cages to continue the urine collection for an additional 4 days. The amount of absorbed compound in the urine was determined by liquid scintillation counting. Approximately 70% was absorbed in rhesus monkeys within 24 hours.