Dizinc pyrophosphate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 Dec 2016-07 Feb 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

Adopted 1987

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesamt für Gesundheit und Soziales, Mecklenburg-Vorpommern, Germany

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dizinc pyrophosphate

EC Number:

231-203-4

EC Name:

Dizinc pyrophosphate

Cas Number:

7446-26-6

Molecular formula:

H4O7P2.2Zn

IUPAC Name:

dizinc(2+) (phosphonooxy)phosphonate

Test material form:

solid: particulate/powder

Details on test material:

- Other: white, odourless

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Remarks:

Crl:(HA)BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: not specified
- Weight at study initiation: 350-450 g
- Fasting period before study: not specified
- Housing: group-caged by sex, not further specified
- Diet: commercial feeding mixture, Mühle Knull, Rostock, Germany, ad libitum
- Water: tap water, supplemented with vitamin C, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30-70
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 28 Dec 2016 To: 07 Feb 2017

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal area of the trunk
- % coverage: 10
- Type of wrap if used: gauze dressing held in place with tape

REMOVAL OF TEST SUBSTANCE
- Washing: residual test material was removed with water
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied: 2000 mg/kg bw
- For solids, paste formed: yes, the test material was moistened with the smallest amount of water sufficient to ensure good skin contact (500 µL) and applied as a paste

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: animals were observed individually before and immediately (Time 0), 5, 15, 30 and 60 min, 3, 6 and 24 hours after application, then daily for 14 days. Individual body weights were determined before test material application and weekly thereafter.
- Necropsy of survivors performed: yes

Statistics:

BW changes and LD50 values were calculated.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the study period.

Clinical signs:

No clinical signs of toxicity were observed at application or up to the end of the 14-day observation period.

Body weight:

One male (1/5) animal showed a slight weight loss after 7 days, but this was considered not relevant. All other animals showed no adverse effect on body weight gain.

Gross pathology:

Necropsy examination revealed no substance-related or abnormal findings.

Other findings:

Examinations of the skin for oedema and erythema were performed at 1, 24, 48 and 72 h and day 14.
The test material caused very slight to moderate irritation (erythema) of the skin in 3/5 of the female animals, with numerical grading of 1-3 after exposure to the test material for 24 hours. Within 14 days after application of the test material, no skin irritation was observed.
The test material caused very slight irritation (erythema) of the skin in 2/5 of the male animals, with a numerical grading of 1 after exposure to the test material for 24 hours. Within 14 days after application of the test material, no skin irritation was observed.

Any other information on results incl. tables

Since no mortality or clinical signs were noted only the skin reactions are presented below:

Skin Reactions -- Numerical Grading and Duration

Skin reaction grades observed
Animal No.	1 h	24 h	48 h	72 h	14 d
1F	0	0	0	0	0
2F	0	0	0	0	0
3F	2**	3***	2**	1*	0
4F	1*	1*	0	0	0
5F	2**	2**	1*	0	0
1M	0	0	0	0	0
2M	0	0	0	0	0
3M	0	0	0	0	0
4M	1*	1*	0	0	0
5M	1*	1*	1*	0	0

* = very slight erythema

** = well-defined erythema

*** = moderate erythema

F = female; M = male

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulation (EC) No 1272/2008.

Conclusions:

The LD50 of dizinc pyrophosphate is >2000 mg/kg bw by the dermal route of exposure in male and female guinea pigs, and therefore the material is not classified.