Potassium dihydrogenorthophosphate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Remarks:

Study was performed prior to the update of the REACH Regulation and prior to the validation of in vitro test methods.

Type of information:

experimental study

Adequacy of study:

key study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: no data

Deviations:

not applicable

Principles of method if other than guideline:

Rabbits were treated topically on each of two test sites and coverd with gauze patches and the trunk of the animal was wrapped with a piece of cheesecloth for 4 h after which the animals were unwrapped and the test material removed. Approximately 30 min after the end of the exposure period, the test sites were scored for irritation using the method of Draize.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Potassium dihydrogenorthophosphate

EC Number:

231-913-4

EC Name:

Potassium dihydrogenorthophosphate

Cas Number:

7778-77-0

Molecular formula:

H3O4P.2K

IUPAC Name:

potassium dihydrogen phosphate

Details on test material:

- Name of test material (as cited in study report): monopotassium phosphate
- Molecular formula (if other than submission substance): no data
- Molecular weight (if other than submission substance): no data
- Smiles notation (if other than submission substance): no data
- InChl (if other than submission substance): no data
- Structural formula attached as image file (if other than submission substance): no data
- Substance type: solid
- Physical state: white powder
- Analytical purity: no data
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Isomers composition: no data
- Purity test date: purity not determined
- Lot/batch No.: reference no. 483B3015A
- Expiration date of the lot/batch: no data
- Radiochemical purity (if radiolabelling): not applicable
- Specific activity (if radiolabelling): not applicable
- Locations of the label (if radiolabelling): not applicable
- Expiration date of radiochemical substance (if radiolabelling): not applicable
- Stability under test conditions: not determined
- Storage condition of test material: room temperature
- Other: FMC-T# 862

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Haxleton Research Animals, Inc., Denver, Pennsylvania.
- Age at study initiation: young adult
- Weight at study initiation: 2.6 to 2.75 kg
- Housing: individually housed in stainless steel cages wiht DACB cageboard bedding in the litter pans
- Diet: no data
- Water: no data
- Acclimation period:


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 68 to 72 ºC
- Humidity (%): 51 - 66 %
- Air changes (per hr): no data
- Photoperiod: 12 h fluorescent light and 12 h dark cycle


IN-LIFE DATES: no data

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped free of hair

Vehicle:

physiological saline

Controls:

not specified

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g of test material moistened with physiological saline
- Concentration (if solution): no data


VEHICLE
- Amount(s) applied (volume or weight with unit): no data
- Concentration (if solution):no data
- Lot/batch no. (if required): no data
- Purity:no data

Duration of treatment / exposure:

4 h

Observation period:

3 days

Number of animals:

Three

Details on study design:

TEST SITE
- Area of exposure: the clipped area extended from the scapular to the pelvic region. One test site was located on each side of the spinal column.
- % coverage: no data
- Type of wrap if used: 8 ply 2x 2 inch gauze pad secured to each test site with hypoallergenic tape. The entire trunk of the animal was wrapped with a semi-occlusive cheesecloth bandage.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): test sites were wiped with clean gauze moistened with methanol and then rinsed with tap water.
- Time after start of exposure:


SCORING SYSTEM: Draize

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

No irritation was noted on any of the test sites during any of hte scoring intervals, and the test was terminated following the 72-h scoring.

Other effects:

All animals remained healthy throughout the study.

Any other information on results incl. tables

Group irritation scores for each scoring interval

Scoring interval	Irritation score
4.5 h	0
24 h	0
48 h	0
72 h	0
Primary irritation index	0/8.0

Pretest examination

Animal #	Body weight (kg)	Test sites
B7853F	2.70	N
B7854F	2.75	N
B7843M	2.60	N

N - normal

Individual skin scores

Animal #	Left			Right
	ER	ED	O	ER	ED	O
4.5 h
B7853F	0	0	0	0	0	0
B7854F	0	0	0	0	0	0
B7843M	0	0	0	0	0	0
Irritation score	0 / 8.0
24 h
B7853F	0	0	0	0	0	0
B7854F	0	0	0	0	0	0
B7843M	0	0	0	0	0	0
Irritation score	0 / 8.0
48 h
B7853F	0	0	0	0	0	0
B7854F	0	0	0	0	0	0
B7843M	0	0	0	0	0	0
Irritation score	0 / 8.0
72 h
B7853F	0	0	0	0	0	0
B7854F	0	0	0	0	0	0
B7843M	0	0	0	0	0	0
Irritation score	0 / 8.0

ER - erythema/eschar

ED - edema

O - other comments

F - female

M - male

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study the test material is non-irritating to intact skin when applied topically to rabbits.

This study is conducted according protocols comparable to the appropriate guidelines (EU ) and under the conditions of GLP. Minor deviations are noted however, the study is considered to be acceptable and to adequately satisfy both the guideline requirement and the regulatory requirement as a key study for this endpoint.
Potassium dihydrogenorthophosphate is not considered to be classified according to Regulation (EC) No. 1272/2008 (EU CLP).