N-(2-ethylhexyl)-8,9,10-trinorborn-5-ene-2,3-dicarboximide

Toxicity to birds

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to birds: acute oral toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

28 June 1990 to 7 March 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

MGK® 264 Insecticide Synergist; 100% Technical; Lot #7437. The test substance had a reported purity of 92.9%.

Dose method:

other: a single dose of the test substance in diluent was orally intubated directly into the crop or proventriculus of each bird using a stainless steel cannula.

Analytical monitoring:

yes

Remarks:

Sub-samples of dose solutions were sent to sponsor for analysis.

Vehicle:

yes

Remarks:

corn oil

Details on preparation and analysis of diet:

Dosage Preparation
The test substance was dispersed in corn oil (Appendix III). The concentration of the test substance in the diluent was adjusted to provide a constant volume to body weight dosage for all treatment birds. The dosages and LD50 value reported were not corrected for purity of the test substance. Nominal dosages used in this study were 292, 486, 810, 1350 and 2250 milligrams of MGK 264 Insecticide Synergist per kilogram of body weight.

Dose Solution Sampling
Samples of the dosing solutions were collected prior to test initiation and during the dosing procedure to verify solution concentration. Samples were frozen and transferred to McLaughlin, Gormley and King Company for analysis.

Test organisms (species):

Anas platyrhynchos

Details on test organisms:

Test Birds
All mallards (Anas platyrhynchos) were 34 weeks of age and appeared to be in good health at initiation of the test. Mallards ranged in weight from 935 to 1352 grams at test initiation. The birds were obtained from Whistling Wings, Box 1,113 Washington Street, Hanover, Illinois 61041. All birds were from the same hatch, pen-reared and phenotypically indistinguishable from wild birds. Birds were assigned to five test groups and one control group. Each treatment or control group contained five males and five females. All test birds were acclimated to the caging and facilities for 19 weeks prior to the initiation of the test.

Limit test:

no

Remarks:

One oral exposure

Post exposure observation period:

14 days

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

Ten mallards, five males and five females, were assigned to each of the treatment groups and the control group by random draw.

Control animals:

yes, concurrent vehicle

Nominal and measured doses / concentrations:

292, 486, 810, 1350 & 2250 mg/kg

Details on test conditions:

Test birds were housed indoors by dosage group in batteries of pens manufactured by Safeguard Products, Inc. (Model No. 5355). Birds were assigned to pens by random draw. Each pen had floor space that measured approximately 75 X 90 cm. Ceiling height was approximately 45 cm. External walls, ceilings and floors were constructed of wire grid. Each dosage group was assigned two pens. One pen contained five males and the other five females. Each group of birds was identified by pen number. Individual birds within each pen were identified by colored leg bands. Birds were maintained at ambient room temperature. Average temperature for this study was 24·C ± 1°C (SD) with an average relative humidity of 66% ± 8% (SD). The photoperiod (maintained by a time clock) was eight hours of light per day during acclimation and throughout the test. The light source was fluorescent lights which closely approximate noon-day sunlight (noon-day sun - 4870· Kelvin, Chroma 50 or equivalent - 5000° Kelvin)". The birds were exposed to approximately 130 lux of illumination.
Housing and husbandry practices were based on guidelines established by the National Institutes of Health (2).

Details on examinations and observations:

Observations
During acclimation all birds were observed daily. Birds exhibiting abnormal behaviour or physical injury were not used. Following test initiation until termination all birds were observed at least twice daily. A record was maintained of all mortality, signs of toxicity, or abnormal behaviour.

Animal Body Weights/Feed Consumption
Body weights were measured individually at initiation of the test and by group on Days 3, 7 and 14. Average estimated feed consumption was determined for each dosage group and the control for Days 0-3, 4-7 and 8-14. Feed consumption was determined by measuring the change in the weight of the feed presented to the birds over a given period of time. However, feed consumption is presented as an estimate due to the unavoidable wastage by the birds.

Details on reproductive parameters:

N/A

Reference substance (positive control):

no

Key result

Dose descriptor:

LD50

Effect level:

> 2 250 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

other: lack of mortality

Key result

Dose descriptor:

NOEL

Effect level:

292 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

signs of toxicity

Remarks:

The no observed effect level was 292 mg/kg based on the signs of toxicity at 486 mg/kg.

Repellency factors (if applicable):

N/A

Mortality and sub-lethal effects:

There were no mortalities at any of the dosages tested (Table 1).

At 292 mg/kg there were no signs of toxicity, and all birds were normal in appearance and behaviour throughout the test period.

Birds at the 486 mg/kg dosage began exhibiting signs of toxicity approximately one half hour after dosing. Signs persisted throughout Day o. By the morning of Day 1 all birds had recovered and were normal in appearance and behaviour until study termination.

At the 810 mg/kg dosage, signs of toxicity were first noted approximately one half hour after dosing, and continued throughout Day 0. One male was noted with a leg injury from the morning of Day 1 through the morning of Day 6, after which the bird fully recovered. This injury was not considered to be treatment related. All other birds were normal in appearance and behaviour throughout the study.

At 1350 mg/kg, signs of toxicity were first noted immediately after dosing and persisted intermittently until the afternoon of Day 0. From the morning of Day 1 until study termination, all birds were normal in appearance and behaviour.

At the 2250 mg/kg dosage signs of toxicity were observed immediately after dosing, and continued to be noted for approximately two hours. By the afternoon of Day 0, all birds had recovered, and were normal in appearance and behaviour for the remainder of the study. Signs of toxicity typical of intoxication with MGK 264 Insecticide Synergist were loss of coordination, reduced reaction to external stimuli (sound and movement), lethargy, and lower limb weakness.

When compared to the controls, there did not appear to be an effect on body weight or feed consumption (Table 2). In conclusion, the acute oral LD50 for mallards exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality dosage was 2250 mg/kg. The no observed effect level was 292 mg/kg based on the signs of toxicity at 486 mg/kg.

Effects on reproduction:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

When compared to the controls, there did not appear to be an effect on body weight or feed consumption (Table 2). In conclusion, the acute oral LD50 for mallards exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality dosage was 2250 mg/kg. The no observed effect level was 292 mg/kg based on the signs of toxicity at 486 mg/kg.

Validity criteria fulfilled:

not specified

Conclusions:

In conclusion, the acute oral LD50 for mallards exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality dosage was 2250 mg/kg. The no observed effect level was 292 mg/kg based on the signs of toxicity at 486 mg/kg.

Executive summary:

There were no mortalities at any of the dosages tested (Table 1).

 

At 292 mg/kg there were no signs of toxicity, and all birds were normal in appearance and behaviour throughout the test period.

 

Birds at the 486 mg/kg dosage began exhibiting signs of toxicity approximately one half hour after dosing. Signs persisted throughout Day o. By the morning of Day 1 all birds had recovered and were normal in appearance and behaviour until study termination.

 

At the 810 mg/kg dosage, signs of toxicity were first noted approximately one half hour after dosing, and continued throughout Day 0. One male was noted with a leg injury from the morning of Day 1 through the morning of Day 6, after which the bird fully recovered. This injury was not considered to be treatment related. All other birds were normal in appearance and behaviour throughout the study.

 

At 1350 mg/kg, signs of toxicity were first noted immediately after dosing and persisted intermittently until the afternoon of Day 0. From the morning of Day 1 until study termination, all birds were normal in appearance and behaviour.

 

At the 2250 mg/kg dosage signs of toxicity were observed immediately after dosing, and continued to be noted for approximately two hours. By the afternoon of Day 0, all birds had recovered, and were normal in appearance and behaviour for the remainder of the study. Signs of toxicity typical of intoxication with MGK 264 Insecticide Synergist were loss of coordination, reduced reaction to external stimuli (sound and movement), lethargy, and lower limb weakness.

 

When compared to the controls, there did not appear to be an effect on body weight or feed consumption (Table 2).

 

In conclusion, the acute oral LD50 for mallards exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality dosage was 2250 mg/kg. The no observed effect level was 292 mg/kg based on the signs of toxicity at 486 mg/kg.

Reference 2

Endpoint:

short-term toxicity to birds: dietary toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

9 July 1990 to 12 October 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 71-2 (Avian Dietary Toxicity Test)

GLP compliance:

yes

Specific details on test material used for the study:

MGK® 264 Insecticide Synergist Technical;
Lot No. 7437
The test substance had a reported purity of 92.9%.

Dose method:

feed

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

corn oil

Details on preparation and analysis of diet:

The test diets were prepared by mixing the test substance into the diet with corn oil (Appendix II). The concentration of corn oil in the treated and control diets was 2%. Mixing of the test diet was done with a Hobart (Model Number AS200T) mixer. Diets were prepared on the day of test initiation and presented to the birds. Additional diet was presented to the birds as needed. The dietary concentrations were not adjusted for purity of the test substance. Therefore all dietary concentrations and the LC50 value are reported as parts per million of the test substance as received. Nominal dietary test concentrations used in this study were 562, 1000, 1780, 3160 and 5620 ppm.

Samples of the test diets were taken to verify the test concentrations administered and to confirm the stability and homogeneity of the test substance in the diets. The samples were shipped to Mclaughlin, Gormley and King Company, 8810 Tenth Avenue North, Minneapolis, Minnesota 55427.

Test organisms (species):

Anas platyrhynchos

Details on test organisms:

All mallards (Anas platyrhynchos) were 10 days of age and appeared to be in good health at initiation of the test. The birds were obtained from Whistling Wings, Box 1, 113 Washington Street, Hanover, Illinois 61041. The birds were hatched on July 9, 1990 and received at Wildlife International Ltd. on July 10, 1990. All birds were from the same hatch, pen-reared and phenotypically indistinguishable from wild birds. Birds were assigned to five test groups and three control groups. Each treatment or control group contained ten ducklings. The birds used in this study were immature and could not be differentiated by sex. All birds were acclimated to the caging and facilities from the day of receipt until initiation of the test.

Limit test:

no

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 per dose or control group (The birds used in this study were immature and could not be differentiated by sex.)

Control animals:

yes, concurrent no treatment

Nominal and measured doses / concentrations:

Nominal dietary test concentrations used in this study were 562, 1000, 1780, 3160 and 5620 ppm. Diet concentrations verified by MGK analysis.

Details on test conditions:

During acclimation and testing, all birds were housed indoors by test group in batteries of brooding pens manufactured by Safeguard Products, Inc. Birds were assigned to pens by random draw. Each pen had floor space that measured approximately 62 X 92 cm. Ceiling height was approximately 25.5 cm. External walls, ceilings and floors were constructed of vinyl coated wire mesh. Each test or control group was assigned a pen that contained ten ducklings. Each group of birds was identified by pen number. During the test, the average temperature in the brooding compartment of the pens was 33°C ± 2°C (SD). Average ambient room temperature for this study was 24°C ± l °C (SD) with an average relative humidity of 75% ± 13% (SD). The photoperiod (maintained by a time clock) was sixteen hours of light per day during acclimation and throughout the test. The light source was fluorescent lights which closely approximate noon-day sunlight (noon-day sun - 4870° Kelvin, Chroma 50 or equivalent - 5000° Kelvin)*. The birds were exposed to approximately 130 lux of illumination.
Housing and husbandry practices were based on guidelines established by the National Institutes of Health (3).

Details on examinations and observations:

Observations
During acclimation all birds were observed daily. Birds exhibiting abnormal behavior or physical injury were not used. Following test initiation and continuing until termination, all birds were observed at least twice daily. A record was maintained of all mortality, signs of toxicity or abnormal behavior.

Animal Body Weights/Feed Consumption
Body weights by group were measured at the initiation of the test, on Day 5, and at termination of the test on Day 8. Average estimated feed consumption was determined for each test and contra l group for the exposure period, Days 0-5, and for the post-exposure observation period, Days 6-8. Feed consumption was determined by measuring the change in the weight of the feed presented to the birds over a given period of time. However, feed consumption is presented as an estimate due to the unavoidable wastage by the birds.

Details on reproductive parameters:

N/A

Reference substance (positive control):

no

Key result

Duration (if not single dose):

5 d

Dose descriptor:

LC50

Effect level:

> 5 620 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

other: The dietary LC50 value for mallards exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested.

Key result

Duration (if not single dose):

5 d

Dose descriptor:

NOEL

Effect level:

5 620 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

other: Lack of sub-lethal observations

Mortality and sub-lethal effects:

There were no mortalities in any of the test concentrations. All birds were normal in appearance and behavior.

Effects on reproduction:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

There were no mortalities in any of the test concentrations. All birds were normal in appearance and behavior.
When compared to controls, there were no effects on body weight gain or feed consumption at any of the concentrations tested.
In conclusion, the dietary LC50 value for mallards exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Validity criteria fulfilled:

not specified

Conclusions:

There were no mortalities in any of the test concentrations. All birds were normal in appearance and behavior.
When compared to controls, there were no effects on body weight gain or feed consumption at any of the concentrations tested.
In conclusion, the dietary LC50 value for mallards exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Executive summary:

There were no mortalities in any of the test concentrations. All birds were normal in appearance and behavior.

When compared to controls, there were no effects on body weight gain or feed consumption at any of the concentrations tested.

In conclusion, the dietary LC50 value for mallards exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Reference 3

Endpoint:

short-term toxicity to birds: acute oral toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

17 September 1990 to 7 March 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

Product: MGK® 264 Insecticide Synergist; 100% Technical; Lot# 7437. The test substance had a reported purity of 93.1% active ingredient.

Dose method:

other: orally intubated directly into the crop or proventriculus of each bird using a stainless steel cannula

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

corn oil

Details on preparation and analysis of diet:

Dosage Preparation
The test substance was dispersed in corn oil (Appendix III). The concentration of the test substance in the diluent was adjusted to provide a constant volume to body weight dosage for all treatment birds. The dosages and LD50 value reported were not corrected for purity of the test substance. Nominal dosages used in this study were 292, 486, 810, 1350 and 2250 milligrams of MGK 264 Insecticide Synergist per kilogram of body weight.

Dose Solution Sampling
Samples of the dosing solutions were collected prior to test initiation and during the dosing procedure to verify solution concentration. Samples were frozen and transferred to McLaughlin, Gormley and King in Minneapolis, Minnesota for analysis.

Test organisms (species):

Colinus virginianus

Details on test organisms:

Test Birds
All northern bobwhite (Colinus virginianus) were 17 weeks of age and appeared to be in good health at initiation of the test. Bobwhite ranged in weight from 163 to 203 grams at test initiation. The birds were obtained from Fritts Quail Farm, Phillipsburg, New Jersey 08865. All birds were from the same hatch, pen-reared and phenotypically indistinguishable from wild birds. Birds were assigned to five test groups and one control group. Each treatment or control group contained five males and five females. All test birds were acclimated to the caging and facilities for 5 weeks prior to the initiation of the test.

Limit test:

no

Post exposure observation period:

Post-dosing observation - 14 days.

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

Ten northern bobwhite, five males and five females, were assigned to each of the treatment groups and the control group by random draw.

Control animals:

yes, concurrent vehicle

Nominal and measured doses / concentrations:

Nominal dosages used in this study were 292, 486, 810, 1350 and 2250 milligrams of MGK 264 Insecticide Synergist per kilogram of body weight.

Details on test conditions:

Housing and Environmental Conditions
Test birds were housed indoors by dosage group in batteries of pens manufactured by GQF Manufacturing Co. (Model No. 0010). Birds were assigned to pens by random draw. Each pen had floor space that measured approximately 78 X 51 cm. Floors were sloped so that ceiling height ranged from approximately 20 to 25 cm. External walls, ceilings and floors were constructed of galvanized wire while side walls were constructed of galvanized sheeting. Each dosage group was assigned two pens. One pen contained five males and the other five females. Each group of birds was identified by pen number. Individual birds within each pen were identified by colored leg bands. Birds were maintained at ambient room temperature. Average temperature for this study was 22°C ± 1°C (SO) with an average relative humidity of 51% ± 11% (SO). The photoperiod (maintained by a time clock) was eight hours of light per day during acclimation and throughout the test. The light source was
fluorescent lights which closely approximate noon-day sunlight (noonday sun - 4870° Kelvin, Chroma 50 or equivalent - 5000° Kelvin)". The
birds were exposed to approximately 130 lux of illumination. Housing and husbandry practices were based on guidelines established
by the National Institutes of Health (2).

Details on examinations and observations:

Observations
During acclimation all birds were observed daily. Birds exhibiting abnormal behavior or physical injury were not used.
Following test initiation until termination all birds were observed at 1 east twice daily. A record was maintained of all mortality, signs of toxicity, or abnormal behavior.

Animal Body Weights/Feed Consumption
Body weights were measured individually at initiation of the test and by group on Days 3, 7 and 14. Average estimated feed consumption was determined for each dosage group and the control for Days 0-3, 4-7 and 8-14. Feed consumption was determined by measuring the change in the weight of the feed presented to the birds over a given period of time. However, feed consumption is presented as an estimate due to the unavoidable wastage by the birds.

Details on reproductive parameters:

N/A

Reference substance (positive control):

no

Key result

Dose descriptor:

LD50

Effect level:

> 2 250 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

other: Lack of mortality at highest dose level (2250 mg/kg)

Key result

Dose descriptor:

NOEL

Effect level:

1 350 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

body weight

Remarks:

The no observed effect level was 1350 mg/kg based on a reduction in body weight gain among males at 2250 mg/kg.

Repellency factors (if applicable):

N/A

Mortality and sub-lethal effects:

There were no mortalities at any of the dosages tested. All birds at all dosages were normal in appearance and behavior throughout the study period (Table 1).
When compared to the controls, there was a reduction in body weight gain among males at the 2250 mg/kg dosage. There was no effect on feed consumption at any of the dosages tested (Table 2).
In conclusion, the acute oral L050 for northern bobwhite exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality level was 2250 mg/kg. The no observed effect level was 1350 mg/kg based on a reduction in body weight gain among males at 2250 mg/kg.

Effects on reproduction:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

In conclusion, the acute oral L050 for northern bobwhite exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality level was 2250 mg/kg. The no observed effect level was 1350 mg/kg based on a reduction in body weight gain among males at 2250 mg/kg.

Validity criteria fulfilled:

not specified

Conclusions:

There were no mortalities at any of the dosages tested. All birds at all dosages were normal in appearance and behavior throughout the study period (Table 1).

When compared to the controls, there was a reduction in body weight gain among males at the 2250 mg/kg dosage. There was no effect on feed consumption at any of the dosages tested (Table 2).

In conclusion, the acute oral L050 for northern bobwhite exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality level was 2250 mg/kg. The no observed effect level was 1350 mg/kg based on a reduction in body weight gain among males at 2250 mg/kg.

Executive summary:

There were no mortalities at any of the dosages tested. All birds at all dosages were normal in appearance and behavior throughout the study period (Table 1).

When compared to the controls, there was a reduction in body weight gain among males at the 2250 mg/kg dosage. There was no effect on feed consumption at any of the dosages tested (Table 2).

In conclusion, the acute oral L050 for northern bobwhite exposed to MGK 264 Insecticide Synergist as a single oral dosage was determined to be greater than 2250 mg/kg, the highest dosage tested. The no mortality level was 2250 mg/kg. The no observed effect level was 1350 mg/kg based on a reduction in body weight gain among males at 2250 mg/kg.

Reference 4

Endpoint:

short-term toxicity to birds: dietary toxicity test

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

9 July 1990 to 12 Oct 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 71-2 (Avian Dietary Toxicity Test)

GLP compliance:

yes

Specific details on test material used for the study:

The test substance, a clear liquid, was received from Mclaughlin, Gormley and King Company on Apri1 24, 1990. It was identified on the label as: "MGK® 264 Insecticide Synergist 100% Technical; Lot No. 7437; Date 04-19-90". The test substance had a reported purity of 92.9%. It was assigned Wildlife International Ltd. identification number WIL-1603
upon receipt.

Dose method:

feed

Analytical monitoring:

no

Vehicle:

yes

Remarks:

The test diets were prepared by mixing the test substance into the diet with corn oil (Appendix II). The concentration of corn oil in the treated and control diets was 2%.

Details on preparation and analysis of diet:

The test diets were prepared by mixing the test substance into the diet with corn oil (Appendix II). The concentration of corn oil in the treated and control diets was 2%. Mixing of the test diet was done with a Hobart (Model Number AS200T) mixer. Diets were prepared on the day of test initiation. An amount of diet sufficient to last the five day exposure period was presented to the birds at initiation of the test.
The dietary concentrations were not adjusted for purity of the test substance. Therefore all dietary concentrations and the LC50 value are reported as parts per million of the test substance as received. Nominal dietary test concentrations used in this study were 562, 1000, 1780, 3160 and 5620 ppm.

Test organisms (species):

Colinus virginianus

Details on test organisms:

All northern bobwhite (Colinus virginianus) were 10 days of age and appeared to be in good health at initiation of the test. The birds were obtained from the Wildlife International Ltd. Production Flock, Easton, Maryland 21601. The birds were hatched on July 9, 1990 at Wildlife International Ltd. A 11 birds were from the same hatch, pen-reared and phenotypically indistinguishable from wild birds. Birds were assigned to five test groups and four control groups. Each treatment or control group contained ten chicks. The birds used in this study were immature and could not be differentiated by sex. All birds were acclimated to the caging and facilities from the day of hatch until initiation of the test.

Limit test:

no

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 group (The birds used in this study were immature and could not be differentiated by sex.)

Control animals:

yes, concurrent vehicle

Nominal and measured doses / concentrations:

Nominal: 562, 1000, 1780, 3160 and 5620 ppm (concentrations examined by MGK - mean concentrations not specified in this report).

Details on test conditions:

During acclimation and testing, all birds were housed indoors by test group in batteries of thermostatically controlled brooding pens manufactured by Beacon Steel Products Co. (Model No. B735Q). Birds were assigned to pens by random draw. Each pen had floor space that measured approximately 72 X 90 cm. Ceiling height was approximately 23 cm. External walls, ceilings and floors were constructed of galvanized steel wire and sheeting. Each test or control group was assigned a pen that contained ten chicks. Each group of birds was identified by pen number. During the test the average temperature in the brooding compartment of the pens was 34°C ± ZOC (SO). Average ambient room temperature for this study was 28°C ± 1°C (SO) with an average relative humidity of 62% ± 11% (SD). The photoperiod (maintained by a time clock) was sixteen hours of light per day during acclimation and throughout the test. The light source was fluorescent lights which closely approximate noon-day sunlight (noon-day sun - 4870· Kelvin, Chroma 50 or equivalent - 5000· Kelvin)". The birds were exposed to approximately 130 lux of illumination.

Details on examinations and observations:

During acclimation all birds were observed daily. Birds exhibiting abnormal behavior or physical injury were not used. Following test initiation and continuing until termination, all birds were observed at least twice daily. A record was maintained of all mortality, signs of toxicity or abnormal behavior.
Body weights by group were measured at the initiation of the test, on Day 5, and at termination of the test on Day 8. Average estimated feed consumption was determined for each test and control group for the exposure period, Days 0-5, and for the post-exposure observation period, Days 6-8. Feed consumption was determined by measuring the change ; in the weight of the feed presented to the birds over a given period of time. However, feed consumption is presented as an estimate due to the unavoidable wastage by the birds.

Details on reproductive parameters:

N/A

Reference substance (positive control):

no

Key result

Duration (if not single dose):

5 d

Dose descriptor:

NOEL

Effect level:

> 5 620 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

other: The dietary LC50 value for the northern Bobwhite exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested.

Key result

Duration (if not single dose):

5 d

Dose descriptor:

LC50

Effect level:

5 620 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

other: Lack of sub-lethal observations

Repellency factors (if applicable):

N/A

Mortality and sub-lethal effects:

There were no mortalities in any of the concentration tested. Two birds at the 562 ppm concentration, and three birds at the 1000 ppm test concentrations were slightly nostril picked on Day 1. This cannibalistic form of aggression was not treatment related and all other birds were normal in appearance and behaviour.

When compared to the controls, there were no effects on body weight gain or feed consumption at any of the concentrations tested.

In conclusion, the dietary LC50 value for northern bobwhite exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Effects on reproduction:

N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

In conclusion, the dietary LC50 value for northern bobwhite exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Validity criteria fulfilled:

not specified

Conclusions:

In conclusion, the dietary LC50 value for northern bobwhite exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Executive summary:

There were no mortalities in any of the concentration tested. Two birds at the 562 ppm concentration, and three birds at the 1000 ppm test concentrations were slightly nostril picked on Day 1. This cannibalistic form of aggression was not treatment related and all other birds were normal in appearance and behaviour.

When compared to the controls, there were no effects on body weight gain or feed consumption at any of the concentrations tested.

In conclusion, the dietary LC50 value for northern bobwhite exposed to MGK® 264 was determined to be greater than 5620 ppm, the highest concentration tested. The highest no mortality level was 5620 ppm. The highest no observed effect level was 5620 ppm.

Key value for chemical safety assessment

Short-term EC50 or LC50 for birds:

5 620 mg/kg food

Additional information

Acute LC50 >5620 mg/kg diet (based on short term studies)

Acute NOEL 292 mg/kg diet (based on mallard acute study)