Mequinol

Repeated dose toxicity: dermal

Administrative data

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Few observation parameters were reported. The test substance (PMP) is applied in a sun tan lotion.

Data source

Reference

Reference Type:

publication

Title:

Short-term toxicity tests on the mono and di methyl ethers of hydroquinone.

Author:

Hodge HC, Sterner JH, Maynard EA and Thomas J

Year:

1949

Bibliographic source:

The Journal of Industrial Hygiene and Toxicolology, 31(2), 79-92.

Materials and methods

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Mequinol

EC Number:

205-769-8

EC Name:

Mequinol

Cas Number:

150-76-5

Molecular formula:

C7H8O2

IUPAC Name:

4-methoxyphenol

Details on test material:

Monomethyl ether hydroquinone (PMP). No other information available.

Test animals

Species:

rabbit

Strain:

not specified

Sex:

male

Details on test animals or test system and environmental conditions:

- Source, age at study initiation, weight at study initiation, fasting period before study, acclimation period: data not available

ENVIRONMENTAL CONDITIONS (housing, temperature, humidity, air changes,  photoperiod): data not available

IN LIFE DATES: data not available 

Administration / exposure

Type of coverage:

not specified

Vehicle:

other: see details

Details on exposure:

- Vehicle: other: sun tan lotion preparation. The sun tan lotions were prepared on 2 basic formulae. One contained the specified amount of ether, 5 g of castor oil, 6 g of water, and alcohol to make 100 g. The  other formula contained the specified amount of ether, 15 g of butyl stearate, and alcohol to make 100 g. - Test site (area of exposure, % coverage, Type of wrap if used): data  not available
- Removal of test substance: no.
- Test material: PMP was applied at 1 and 10% concentration
- Vehicle: 5 mL
- Post exposure period: none

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

30 days

Frequency of treatment:

5 days a week

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 1 and 10%
Basis:
no data

Control animals:

yes, concurrent vehicle

Details on study design:

Post-exposure period: none

Positive control:

none

Examinations

Observations and examinations performed and frequency:

- Body weight: Yes (weekly)
- Mortality:  No data
- Food consumption: No data
- Water consumption; No data
- Clinical signs: No data
- Functional observations: No data
- Ophtalmoscopic examination: No data
- Haematology: Yes (prior to experimentation, after 2 and 4 weeks)
- Clinical chemistry: No data
- Urinalysis: Yes

Sacrifice and pathology:

- Organ weight examined:  liver, kidneys, testes, spleen, brain, heart,  lungs, stomach
- Gross pathology: No data
- Histopathology: Yes

Statistics:

no data

Results and discussion

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

- Clinical signs: no data
- Mortality: no data
- Body weight: yes. There was little evidence of the effect of the  treatment in body weight, although some of the rabbits receiving PMP  

showed mild weight loss.
- Food consumption and compound intake: no data
- Food efficiency: no data
- Water consumption and compound intake: no data
- Ophtalmoscopic examination: no data
- Haematology: yes. The hematological findings were within normal limits in all tested groups.
- Clinical chemistry: no data
- Urinalysis: yes. There were no significant values.
- Gross pathology: no data
- Organ weights: yes. Organ weight did not reveal evidence of a toxic reaction except some tendency to decrease in testes weights was observed  

and the spleen weights showed a tendency to increase.
- Histopathology: yes. In the skin, dryness and crusting of the surface was observed. Microscopic changes ranging from atrophy of the epidermis  

to ulceration and inflammation were seen.

Applicant's summary and conclusion

Conclusions:

Dermal toxicity study was conducted on rabbits in which 0, 1 and 10% PMP was applied to the bare skin in a sun tan lotion base. Application were
made daily 5 times per week for 30 days.
Body weight losses were small. Urine analyses were negative. Hematological findings were within normal limits. Autopsy findings were largely
negative, except that evidences of irritation of the skin were questionable.