Cyanoguanidine

Toxicity to birds

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to birds: dietary toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1985

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 71-2 (Avian Dietary Toxicity Test)

Deviations:

yes

Remarks:

only 3 dose groups, 1x control, but highest dose 5000 ppm --> no toxicity (limit test); specifications with sponsor; observations only 1x on first day

Qualifier:

according to guideline

Guideline:

OECD Guideline 205 (Avian Dietary Toxicity Test)

Deviations:

yes

Remarks:

only 3 dose groups, 1x control, but highest dose 5000 ppm --> no toxicity (limit test); specifications with sponsor; observations only 1x on first day

GLP compliance:

no

Dose method:

feed

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Anas platyrhynchos

Limit test:

yes

Total exposure duration (if not single dose):

5 d

Post exposure observation period:

3 days

No. of animals per sex per dose and/or stage:

10 animals per dose; sex not specified since not identifiable at an age of 10 days

Control animals:

yes, plain diet

Key result

Duration (if not single dose):

5 d

Dose descriptor:

LC50

Effect level:

> 5 000 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Validity criteria fulfilled:

yes

Conclusions:

The avian dietary LC50 for dicyandiamide in mallard ducks is in excess of 5000 ppm.
Under the condictions of this test dicyandiamide was not toxic towards mallard ducks.

Executive summary:

The short-term dietary toxicity of dicyandiamide to 10 day old mallard ducks (Anas platyrhynchos) was assessed over 5 days in accordance with the EPA OPP 71-2 (Avian Dietary Toxicity Test) and OECD guideline 205 (avian dietary toxicity test). Dicyandiamide was administered to the birds (10 per treatment) in the diet at nominal concentrations of 0, 1250, 2500 and 5000 ppm in the diet. 

The 5 day acute dietary LC₅₀was in excess of 5000 ppm in the diet.

Body weight gains were normal during the 5-day treatment period and the 3 post- treatment days of the study. Feed consumption was not affected. No signs of toxicity were noted.

This toxicity study is classified as acceptable and satisfies the guideline requirement for the avian dietary toxicity test.

Reference 2

Endpoint:

short-term toxicity to birds: dietary toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1985

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 71-2 (Avian Dietary Toxicity Test)

Deviations:

yes

Remarks:

only 3 dose groups, but highest dose 5000 ppm --> no toxicity (limit test); specifications with sponsor; observations only 1x on first day

Qualifier:

according to guideline

Guideline:

OECD Guideline 205 (Avian Dietary Toxicity Test)

Deviations:

yes

Remarks:

only 3 dose groups, but highest dose 5000 ppm --> no toxicity (limit test); specifications with sponsor; observations only 1x on first day

GLP compliance:

no

Dose method:

feed

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Colinus virginianus

Limit test:

yes

Total exposure duration (if not single dose):

5 d

Remarks:

treatment period was followed by 3 days feeding of untreated basal diet

No. of animals per sex per dose and/or stage:

10 animals per dose; sex not specified

Control animals:

yes, plain diet

Key result

Duration (if not single dose):

5 d

Dose descriptor:

LC50

Effect level:

> 5 000 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Validity criteria fulfilled:

yes

Conclusions:

The avian dietary LC50 for dicyandiamide in bobwhite quail is in excess of 5000 ppm.
Under the condictions of this test dicyandiamide was not toxic towards bobwhite quail.

Executive summary:

The acute dietary toxicity of dicyandiamide to 13 day old bobwhite quail (Colinus virginianus) was assessed over 5 days in accordance with the EPA OPP 71-2 (Avian Dietary Toxicity Test) and OECD guideline 205 (Avian Dietary Toxicity Test). Dicyandiamide was administered to the birds (10 per treatment) in the diet at nominal concentrations of 0, 1250, 2500 and 5000 ppm in the diet. 

The 5 day acute dietary LC₅₀was in excess of 5000 ppm in the diet.

Body weight gains were normal during the 5-day treatment period and the last 3 post- treatment days of the study. Feed consumption was not affected. No signs of toxicity were noted.

This toxicity study is classified as acceptable and satisfies the guideline requirement for the avian dietary toxicity test.

Reference 3

Endpoint:

short-term toxicity to birds: acute oral toxicity test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1985

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 71-1 (Avian Acute Oral Toxicity Test)

Deviations:

yes

Remarks:

only 3 dose levels instead of 5, but could pass as limit test since 2000 mg/kg was tested; clinical examinations on first day should be 3x beyond first 2 hrs. Only first 3 hrs examined, but no effects observed.

GLP compliance:

not specified

Dose method:

capsule

Analytical monitoring:

yes

Vehicle:

no

Details on preparation and analysis of diet:

TEST MATERIAL PREPARATION
- Description and nutrient analysis of basal diet provided in study report: Yes
- Preparation of doses: The test material was weighed into gelatine capsules according to each bird's weight (mg/kg) and sealed

Test organisms (species):

Anas platyrhynchos

Details on test organisms:

TEST ORGANISM
- Common name: Mallard duck
- Source: Whistling Wings, Hanover, Illinois, USA
- Age at test initiation (mean and range, SD): 17 weeks
- Weight at test initiation (mean and range, SD): males: 1179-1268 g; females: 1052-1104 g
- Sexes used: male and female

Limit test:

no

Remarks:

Single dose, oral (by capsule).

Post exposure observation period:

The birds were observed for pharmacotoxic signs (including regurgitation) hourly for 3 hours, then daily until termination of the study. A 4-hour observation was not conducted.
Total observation period: 14 days

No. of animals per sex per dose and/or stage:

Five animals per sex per dose

Control animals:

yes, concurrent no treatment

Nominal and measured doses / concentrations:

Not applicable

Details on test conditions:

ACCLIMATION
- Acclimation period: 20 days prior to testing
- Acclimation conditions (same as test or not): Yes
- Feeding: Purina Duck Growena, Product 8815, Lot. No. 4742501
- Health (any disease or mortality observed): No
- Fasting period before study: Yes, overnight fasting prior to dosing; animals were returned to ad libitum feeding immediately after dosing

FEED WITHHOLDING PERIOD BEFORE DOSING
- No. of days: Only overnight

PEN SIZE AND CONSTRUCTION MATERIALS
- Description: 84 × 84 × 33 cm battery cages with wire mesh floors and outside walls
- Floor covering: Wire mesh floor
- Compliant to good husbandry practices: Yes
- Suitable to avoid crowding stress: Yes
- Caging: Group, 5 birds per pen

NO. OF BIRDS PER REPLICATE
- For negative control: 5
- For treated: 5

NO. OF REPLICATES PER GROUP
- For negative control: 5
- For treated: 5

TEST CONDITIONS (range, mean, SD as applicable)
- Temperature: 14-24 °C
- Relative humidity (%): 35-32
- Photoperiod: 12/12 h
- Ventilation: Well ventilated
- Shielding: Against loud noise or other disturbances

RANGE FINDING STUDY
Not conducted.

Details on examinations and observations:

MORTALITY / CLINICAL SIGNS
- Time schedule for examinations: The birds were observed for pharmacotoxic signs (including regurgitation) hourly for 3 hours, then daily until the termination of the study. A 4-hour observation was not conducted.


BODY WEIGHT
- Time schedule for examinations: prior to treatment (for determination of doses), at day 7, and at day 14
- Remarks: recorded to the nearest gram


FOOD CONSUMPTION
- Time schedule for examinations: data were collected and expressed as average bird/day consumption during the same intervals as body weight
- Remarks: recorded to the nearest gram


REGURGITATION
- Test material was regurgitated: no

Details on reproductive parameters:

Not applicable

Reference substance (positive control):

no

Key result

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: Administration of single dose

Mortality and sub-lethal effects:

MORTALITY
No mortality occurred during the study


CLINICAL SIGNS
- Results: None of the control birds, nor any of the birds dosed with the test material exhibited any abnormal behaviour or condition which would indicate toxicity at any time during the post-dose period.
- Remarks: A 4-hour observation was not conducted as all birds appeared normal during the first hourla observations.


BODY WEIGHT
- Results: Body weights were not affected at any of the dose levels


FOOD CONSUMPTION (if feeding study)
- Results: Food consumption was not affected at any of the dose levels


GROSS PATHOLOGY
- A post-mortem examination was not conducted at any of the birds

Effects on reproduction:

Not examined

Results with reference substance (positive control):

Not applicable

Further details on results:

No further details reported

Reported statistics and error estimates:

Statistical analysis was not required.

Table 1: Summary of body weights

Treatment level mg/kg dicyandiamide	Sex	Body weight g
		Day 0	Day 7	Day 14
Capsule control A	M F	1215 1088	1190 1057	1196 1066
Capsule control B	M F	1257 1052	1240 1047	1241 1031
2000	M F	1232 1104	1205 1069	1200 1082
1000	M F	1179 1053	1142 1026	1125 1029
500	M F	1268 1035	1238 1020	1241 1028

 

Validity criteria fulfilled:

yes

Conclusions:

The single-dose oral LD50 for dicyandiamide in mallard ducks is in excess of 2000 mg/kg of body weight.
Under the conditions of this test dicyandiamide was not toxic towards mallard ducks.

Executive summary:

The acute oral toxicity of dicyandiamide to 17 week old mallard ducks (Anas platyrhynchos) was assessed over a 14 day post-dose observation period in accordance with the EPA OPP 71-1 (Avian Acute Oral Toxicity Test). Dicyandiamide was administered to 5 birds per sex per dose by single oral gavage (capsule) at 0 (control), 500, 1000, and 2000 mg/kg bw. 

The single-dose oral LD₅₀ for dicyandiamide was > 2000 mg/kg bw.

No evidence of toxicity was observed at any time during the 14 day post-dose observation period.

This toxicity study is classified as acceptable and satisfies the guideline requirement for the avian acute oral toxicity test.

Reference 4

Endpoint:

long-term toxicity to birds: reproduction test

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

The results of three avian toxicity tests (acute/short-term) show that dicyandiamide is not toxic towards mallard duck and bobwhite quail under the conditions of the tests and constitutes no hazard to avian wildlife.

Additional information

The acute and short-term oral toxicity of dicyandiamide to birds was examined in three tests. In the first study (Robaidek and Johnson, 1985), the acute oral toxicity of dicyandiamide to 17 week old mallard ducks (Anas platyrhynchos) was assessed over a 14 day post-dose observation period in accordance with the EPA OPP 71-1 (Avian Acute Oral Toxicity Test). Dicyandiamide was administered to 5 birds per sex per dose level singly by capsule at 0 (control), 500, 1000, and 2000 mg/kg bw. In a second study (Arndt, 1985), the short-term dietary toxicity of dicyandiamide to 13 day old bobwhite quail (Colinus virginianus) was also assessed over 5 days in accordance with the EPA OPP 71-2 and OECD guideline 205 (avian dietary toxicity test). Dicyandiamide was administered to the birds (10 per treatment) in the diet at nominal concentrations of 0, 1250, 2500 and 5000 ppm in the diet. No mortality and no signs of toxicity were observed. In a third study (Robaidek, 1985), the short-term dietary toxicity of dicyandiamide to 10 day old mallard ducks (Anas platyrhynchos) was assessed over 5 days in accordance with the EPA OPP 71-2 and OECD guideline 205 (avian dietary toxicity test). Dicyandiamide was administered to the birds (10 per treatment) in the diet at nominal concentrations of 0, 1250, 2500 and 5000 ppm in the diet. No mortality and no signs of toxicity were observed.

The avian dietary test provides a quantitative measurement of mortality and can act as a range-finder for the chronic reproduction test. According to ECHA Guidance on information requirements, R.7.10.16.1, laboratory data on avian toxicity, p. 92, a full test for chronic reproduction is not necessary if the range-finding test shows that the LC50 is above 5000 mg/kg diet.

Moreover, it should be considered that, according to the ECHA guidance on information requirements, chapter R.7.C (p.98), the exposure of birds is generally only considered for the fish and earthworm food chains following the release of a substance via a sewage treatment works. It is unlikely that a secondary poisoning risk will be identified for substances that:

- are readily biodegradable (dicyandiamide was not found to be readily biodegradable in a test according to OECD guideline 301E, but it is quickly biodegradable in soil)

- have a low potential for bioaccumulation in fish and earthworms (log Kow of dicyandiamide = -1.0)

From these results it can be concluded that dicyandiamide does not pose any hazard to avian wildlife.