Cyanoguanidine

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 1984 - January 1985

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

not specified

GLP compliance:

no

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cyanoguanidine

EC Number:

207-312-8

EC Name:

Cyanoguanidine

Cas Number:

461-58-5

Molecular formula:

C2H4N4

IUPAC Name:

1-cyanoguanidine

Test material form:

solid: particulate/powder

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Hazelton Dutchland, Inc., Denver, Pennsylvania
- Weight at study initiation: males: 2099 - 2454 g; females: 2093 - 2446 g
- Housing: individually in elevated wire-mesh cages
- Diet (ad libitum): commercial rabbit ration (Purina Lab Rabbit Chow)
- Water (ad libitum): tap water
- Acclimation period: minimum -> one week prior to initiation of treatment

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: back of rabbits, hair was closely clipped; skin was left intact
- Type of wrap if used: nonabsorbent binder composed of rubber damming


REMOVAL OF TEST SUBSTANCE
- Washing (if done): exposure sites were wiped with water
- Time after start of exposure: 24 hours


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw
- Constant volume or concentration used: yes
- For solids, paste formed: no

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

Five

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations for signs of toxic and pharmacologic effects: immediately after dosing, at one and four hours postdose, and once daily thereafter for fourteen consecutive days; mortality/moribundity was recorded twice daily
- Individual body weights were recorded prior to treatment, on Day 7 and at death or termination
- Necropsy of survivors performed: yes
- Other examinations performed: dermal responses were graded and scored on Days 1, 3, 7, 10, and 14 according to the system of Draize (1959)

Statistics:

No data

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortality occured during the study.

Clinical signs:

other: All animals appeared normal throughout the study.

Gross pathology:

No observable gross pathology was noted in any animal at necropsy.

Other findings:

Dermal Irritation:
- Slight erythema (Grade 1) was noted in one male at day 1.
- All others appeared normal.

Any other information on results incl. tables

Table 1: Individual Body Weights, Acute Dermal Toxicity Study in Rabbits, 2000 mg/kg

Animal Number	Body Weight - Grams
	Initiation	Day 7	Day 14
Males
E37343	2445	2636	2830
E37344	2267	2449	2650
E37345	2454	2747	2870
E37346	2374	2717	2710
E37347	2099	2150	2300
Females
E37407	2120	2185	2370
E37408	2321	2287	2375
E37409	2446	2730	2960
E37410	2093	2132	2360
E37411	2446	2634	2480

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute dermal LD50 was estimated to be greater than 2000 mg/kg bw.

Executive summary:

In an acute dermal toxicity study, groups of New Zealand White rabbits (5 animals per sex) were dermally exposed to Dicyandiamide for 24 hours at a dose of 2000 mg/kg bw (limit test).  Animals then were observed for 14 days.

Dermal LD50: males > 2000 mg/kg bw; females > 2000 mg/kg bw; combined > 2000 mg/kg bw

No mortality occurred during the study. All animals occurred normal throughout the study. Slight erythema (Grade 1) occurred in one male on Day 1. All others appeared normal. No observable gross pathology was noted in any animal at necropsy. Dicyandimaid is relatively harmless based on the results of this study.