Zinc bis[O-(2-ethylhexyl)] bis[O-(isobutyl)] bis(dithiophosphate)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study was designed to evaluate the implications of differences in test material removal on study outcome and therefore was not strictly an OECD 404 protocol. It was performed by GLP, however, and followed key elements of guidelines making findings reliable with restrictions.

Data source

Reference

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Zinc bis[O-(2-ethylhexyl)] bis[O-(isobutyl)] bis(dithiophosphate)

EC Number:

247-810-2

EC Name:

Zinc bis[O-(2-ethylhexyl)] bis[O-(isobutyl)] bis(dithiophosphate)

Cas Number:

26566-95-0

Molecular formula:

C12H27O2PS2.1/2Zn

IUPAC Name:

Zinc, bis[O-(2-ethylhexyl) O-(2-methylpropyl) phosphorodithioato-κS,κS']-, (T-4)-

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 11-13 weeks
- Housing: Housed individually in wire-bottom cages
- Diet (e.g. ad libitum): rationed
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 15-36 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.8-23.1
- Humidity (%): 60.6-68%
- Photoperiod (hrs dark / hrs light): 12 hours

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 ml

Duration of treatment / exposure:

4 hours

Number of animals:

6

Details on study design:

TEST SITE
- Type of wrap if used: gauze wrapped in plastic sheet


REMOVAL OF TEST SUBSTANCE
- Washing (if done): wiped with dry pad or wiped with gauze pads moistened with mineral oil followed by a dry gauze pad
- Time after start of exposure: 4 hours


SCORING SYSTEM: Draize

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24-72 hours

Score:

1.3

Remarks on result:

other: Mineral oil wipe

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24-72 hours

Score:

0.5

Remarks on result:

other: Mineral oil wipe

Results 3

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24-72 hours

Score:

2.8

Remarks on result:

other: Dry gauze wipe

Results 4

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24-72 hours

Score:

1.3

Remarks on result:

other: Dry gauze wipe

Applicant's summary and conclusion

Interpretation of results:

Category 3 (mild irritant) based on GHS criteria

Remarks:

Migrated information

Conclusions:

When the test material was completely removed from the skin, irritation was substantially reduced to below thresholds requiring hazard classification.

Executive summary:

3 different zinc dialkyldithiophosphates were tested for skin irritation potential using two different methods of test material removal. This study demonstrates that appropriate procedures are required to ensure complete removal of hydprophobic test materials that are present in diluent oil.