Dichlobenil

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:

key study

Study period:

02 November 1993 to 14 November 1994

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)

Deviations:

no

GLP compliance:

yes

Dose method:

capsule

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Colinus virginianus

Details on test organisms:

TEST ORGANISM
- Common name: Bobwhite Quail
- Age at test initiation (mean and range, SD): at least 16-18 weeks old
- Sexes used: male and female
- Disease free: yes (daily check performed during acclimation period)

Limit test:

no

Remarks:

One dosing

Post exposure observation period:

15 days

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

Five

Control animals:

yes

Nominal and measured doses / concentrations:

400, 800, 1086, 1474 and 2000 mg/kg bw

Details on test conditions:

ACCLIMATION
- Acclimation period: at least fifteen days
- Feeding: Avian Layer Diet, Special Diet Services, Witham, Essex, UK ad libitum
- Health (any disease or mortality observed): no

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

PEN SIZE AND CONSTRUCTION MATERIALS
- Description: stainless steel grid cages
- Caging: individual

NO. OF BIRDS PER REPLICATE
- For treated: five per sex

TEST CONDITIONS (range, mean, SD as applicable)
- Temperature: 18-25 ºC
- Relative humidity (%): 40-70 %
- Photoperiod: eight hours light/16 hours dark
- Ventilation: approximately fifteen air changes per hour

RANGE FINDING STUDY
- Test concentrations: 2000 ppm
- Test conditions: as main test
- Results used to determine the conditions for the definitive study: yes (one male and one female treated at 2000 ppm, both died within 7 days. 2000 ppm used as highest dose in main study).

Details on examinations and observations:

MORTALITY / CLINICAL SIGNS
- Time schedule for examinations: three times on day 1 and at least once daily from day 2 onwards

BODY WEIGHT
- Time schedule for examinations: day before dosing (day -1), days 1, 8 and 15.

FOOD CONSUMPTION (if feeding study)
- Time schedule for examinations: weekly

PATHOLOGY
- Dose groups that were examined: all
- Remarks: all body cavities were opened, larger organs were sectioned and the intestinal tract was opened at intervals for examination of mucosal surfaces.

Reference substance (positive control):

no

Key result

Dose descriptor:

LD50

Effect level:

683 mg/kg bw

Conc. / dose based on:

test mat.

Remarks on result:

other: 95 % CL 549-818 mg/kg bw

Key result

Dose descriptor:

LD50

Effect level:

698 mg/kg bw

Conc. / dose based on:

test mat.

Remarks on result:

other: males only

Key result

Dose descriptor:

LD50

Effect level:

727 mg/kg bw

Conc. / dose based on:

test mat.

Remarks on result:

other: females only

Mortality and sub-lethal effects:

Ante mortem signs comprised under-activity, resting on hocks, reluctance or inability to stand, staggering gait, unconsciousness, prone position, slow and deep respiration, closed eyes, thin body conformation, cold to touch, ungroomed appearance, plumo-erection, little diet eaten, few faeces and feather loss. Some birds treated at 2000 mg/kg also had pink staining in the under-trays. Signs of reaction to treatment in surviving birds comprised thin body conformation, plumo-erection, little diet eaten and few faeces. All of these birds were overtly normal on day 13.

The food consumption of birds treated at 400 mg/kg was considerably lower than that of control birds during the first week of the study. Thereafter, the food consumption of these birds was similar to that of the controls. Other surviving birds treated with the test material consumed little diet throughout the study.

Birds treated at 400 mg/kg lost considerable body weight during the first week of the study, but made substantial gains during the second week. The remaining surviving birds treated with the test substance lost body weight throughout the study. Necropsy findings were unremarkable.

Table 1: Mortality distribution

	Mortality
Dose (mg/kg)	Males	Females
0	0/5	0/5
400	0/5	0/5
800	5/5	4/5
1086	3/5	5/5
1474	5/5	5/5
2000	5/5	5/5

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the test, the acute oral median LD50 of the test material was 683 mg/kg bw (95 % C.I. 549-818 mg/kg bw).

Executive summary:

In a GLP compliant acute oral toxicity to birds study conducted in line with standardised guideline EPA 71-1, the acute oral toxicity of the test material to bobwhite quail was determined. The test material was administered by capsule as a single dose, followed by a 15 day observation period, at 0, 400, 800, 1086, 1474 and 2000 mg/kg. Under the conditions of the test the LD₅₀value was determined to be 683 mg/kg bw (95 % C.I. 549-818 mg/kg bw).

Reference 2

Endpoint:

short-term toxicity to birds: dietary toxicity test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 June 1987 to 24 March 1988

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)

Deviations:

no

GLP compliance:

yes

Dose method:

feed

Analytical monitoring:

no

Vehicle:

no

Details on preparation and analysis of diet:

DIET PREPARATION
- Description and nutrient analysis of basal diet provided in study report: no
- Preparation of doses: weighed amount of test material was added to untreated diet to give a premix of 25000 ppm which was mixed by being shaken in a polythene bag for a minimum of three minutes. Aliquots of the premix were used to prepare the final inclusion levels.

Test organisms (species):

Anas platyrhynchos

Details on test organisms:

TEST ORGANISM
- Common name: Mallard duck
- Age at test initiation (mean and range, SD): 10 days old
- Weight at test initiation (mean and range, SD): mean 71 g
- Sexes used: not determined

Limit test:

no

Total exposure duration (if not single dose):

5 d

Post exposure observation period:

Three days

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

Ten animals per dose (sex not identified)

Control animals:

yes, plain diet

Nominal and measured doses / concentrations:

0, 650, 1300, 2600 and 5200 ppm

Details on test conditions:

PEN SIZE AND CONSTRUCTION MATERIALS
- Description: galvinzed steel tiered brooders

NO. OF BIRDS PER REPLICATE
- For treated: 10

TEST CONDITIONS (range, mean, SD as applicable)
- Room temperature: 26 ± 1 ºC - 29 ± 1 ºC
- Relative humidity: mean 65 ± 10 %
- Photoperiod: continuous illumination
- Ventilation: adjusted as required

Details on examinations and observations:

MORTALITY / CLINICAL SIGNS
- Time schedule for examinations: daily

BODY WEIGHT
- Time schedule for examinations: group-weighed on days -3, 0 (prior to introduction of diets), 5 and 8

FOOD CONSUMPTION (if feeding study)
- Time schedule for examinations: over the following days: -3 to -1, 1 to 5 (daily) and 6 to 8.

PATHOLOGY
- Dose groups that were examined: eight surviving birds treated at 5200 ppm and two surviving birds treated at 2600 ppm were examined macroscopically at the termination of the study.

Reference substance (positive control):

no

Key result

Duration (if not single dose):

5 d

Dose descriptor:

LC50

Effect level:

> 5 200 mg/kg diet

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Mortality and sub-lethal effects:

Two mortalities occurred in the 5200 ppm treatment period. All birds were in good health during pre-treatment period. During the treatment period birds dosed at 2600 ppm and 5200 ppm became subdued and were huddled together. Birds in all other groups remained in good health throughout the treatment period. All birds appeared to be in good health during the post-treatment period. Body weight changes and an overview of the deaths occurring are given in Table 1.

Birds in the controls and the 650 ppm treatment group comparable body weight increase, birds in the 1300 ppm treatment group showed a reduced increase during the treatment period, birds in the 2600 ppm treatment group showed only a very small increase during the treatment period, while the surviving birds in the 5200 ppm treatment group showed an actual decrease during the treatment period. During pre- and post-treatment period body weights changes were similar in all groups.

There was a treatment related depression of food consumption in the three highest treatment groups during the treatment period, but it increased again during the post-treatment period. The two birds in the 5200 ppm treatment group, which died during the treatment period, were examined microscopically and both birds were found to be thin. At termination of the study a total number of ten birds (two from the 2600 ppm treatment group and eight from the 5200 ppm treatment group) were examined. No abnormalities were detected.

Table 1: Avian dietary toxicity to the mallard duck (deaths and group mean body weight changes)

Dose units (mg/kg)	0	0	0	650	1300	2600	5200
Mortality	0/10	0/10	0/10	0/10	0/10	0/10	2/10
Days of study	Group mean body weight change in g/bird
-3 to 0	+36	+41	+44	+37	+41	+40	+36
0 to 5	+102	+95	+99	+97	+64	+7	-15
5 to 8	+44	+47	+49	+52	+47	+59	+53

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the test, it was not possible to determine a LC50 value since only two mortalities occurred at the highest dose level tested. The LC50 for the test material in the mallard duck is therefore >5200 mg/kg diet.

Executive summary:

In a GLP compliant short-term dietary toxicity to birds study conducted in line with standardised guideline EPA 71-2, the short-term dietary toxicity of the test material to mallard ducks was determined. The test material was administered by dietary inclusion at 650 1300, 2500 and 5200 ppm. Under the conditions of the test it was not possible to determine a LC₅₀value because there were only two mortalities at the highest dose level tested. This value must therefore be in excess of 5200 mg/kg diet.

Reference 3

Endpoint:

long-term toxicity to birds: reproduction test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 November 1999 to 07 September 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 206 (Avian Reproduction Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 71-4 (Avian Reproduction Test)

Deviations:

no

GLP compliance:

yes

Dose method:

feed

Analytical monitoring:

yes

Vehicle:

no

Details on preparation and analysis of diet:

DIET PREPARATION
- Description and nutrient analysis of basal diet provided in study report: yes
- Preparation of doses: test substance was mixed into a premix that was used for weekly preparation of the final diet.

HOMOGENEITY AND STABILITY OF TEST MATERIAL IN DIET
- How often was homogeneity and stability tested: on day 0 of week 1 and then during weeks 2, 3, 4, 8, 12, 16 and 20.
- When and at what dose levels were samples of treated food analysed for stability and concentration during the study: all dose levels.
- % of nominal: 91.0-98.7 %

Test organisms (species):

Colinus virginianus

Details on test organisms:

TEST ORGANISM
- Common name: Northern bobwhite quail
- Age at test initiation (mean and range, SD): 20 weeks
- Weight at test initiation (mean and range, SD): 180-223 g
- Sexes used: male/female

Limit test:

no

Total exposure duration (if not single dose):

22 wk

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

Sixteen

Control animals:

yes, plain diet

Nominal and measured doses / concentrations:

0, 150, 300 and 600 ppm (nominal)

Details on test conditions:

ACCLIMATION
- Acclimation period: 6 weeks

PEN SIZE AND CONSTRUCTION MATERIALS
- Description: 27 x 51 cm galvanised wire mesh/galvanised sheeting pens with ceiling height of 20-25 cm
- Compliant to good husbandry practices: yes
- Caging: one male and one female per pen

NO. OF BIRDS PER REPLICATE
- For treated: 16

TEST CONDITIONS (range, mean, SD as applicable)
- Room temperature: 19.4 ± 1.6 ºC
- Relative humidity (%): 37 ± 12 %
- Photoperiod: 8 hours light per day in the first seven weeks and then 17 hours per day to induce egg laying
- Ventilation: vent up to 15 room air volumes every hour and replace with fresh air

Details on examinations and observations:

MORTALITY / CLINICAL SIGNS
- Time schedule for examinations: daily

BODY WEIGHT
- Time schedule for examinations: at test initiation, weeks 2, 4, 6, 8 and at termination but not during egg laying to prevent adverse effects on egg production.

FOOD CONSUMPTION (if feeding study)
- Time schedule for examinations: weekly
- Remarks: presented as an estimate because it was not possible to measure wasted feed.

PATHOLOGY
- Dose groups that were examined: all
- Remarks: all animals that died or euthanised during the course of study and all surviving animals at termination.

Details on reproductive parameters:

The following parameters were examined per parental pen per week:
- Eggs laid
- Eggs cracked; eggs broken
- Egg abnormalities
- Eggshell thickness or eggshell strength
- Eggs fertile
- Embryos viable
- Normal hatchlings
- 14-day old surviving chicks
- Chick body weight at hatching and 14 days after hatching

Reference substance (positive control):

no

Key result

Duration (if not single dose):

22 wk

Dose descriptor:

NOEC

Effect level:

150 other: ppm

Conc. / dose based on:

test mat.

Basis for effect:

reproductive parameters

Remarks:

egg production, hatchability and offspring survival

Mortality and sub-lethal effects:

No mortalities occurred in the 300 ppm treatment group, two incidental mortalities occurred in the control group and one incidental mortality occurred in both the 150 and 600 ppm treatment groups; none of these are considered to be treatment-related.

No overt signs of toxicity were observed at any of the concentrations tested. Except for incidental findings (including foot, leg, back, wing and head lesions, feather loss, bruising, lameness, lower limb weakness, reduced reaction to external stimuli, ruffled appearance), all birds appeared normal throughout the study.

All surviving adults were subjected to gross necropsy following adult termination (see Table 1). All findings were considered unrelated to treatment.

There were no apparent treatment-related effects upon adult body weight at any of the concentrations tested (see Table 2).

There were slight, but statistically significant, differences in the mean body weights of cocks in all treatment groups. They were primarily the result of the presence of two heavier males in the control group and very tight standard deviations for all groups. The slight differences observed were not considered biologically meaningful or related to treatment.

There were no apparent treatment-related effects upon feed consumption. No statistically significant differences were observed at any of the feed consumption intervals.

Effects on reproduction:

There were no treatment-related effects upon any of the reproductive parameters measured at the 150 ppm test concentration.

While not statistically significant, there were slight, but treatment-related, reductions in egg production and offspring survival in the 300 ppm treatment group. The reductions in egg production and offspring survival also were reflected as non-statistically significant reductions in 14-day old survivors as a percentage of eggs set, and hatchlings as a percentage of the maximum number of eggs set, and as a statistically significant (p <0.01) reduction in 14-day old survivors as a percentage of the maximum number of eggs set.

There were marked, treatment related, effects on reproductive performance at the 600 ppm test concentration. When compared to the control group, the observed reductions in egg production, hatchability and offspring survival were statistically significant at p <0.01. The reductions were further reflected as statistically significant (p <0.05 and p <0.01) reductions in hatchlings and 14-day old survivors as percentages of both eggs set and the maximum number of eggs set. Summaries of the reproductive data can be found in Table 3.

There were no apparent treatment related effects upon eggshell thickness. There were no apparent treatment related effects upon offspring body weights at the 150 or 300 ppm test concentrations and any differences from the control group were not statistically significant for either the hatchlings or the 14-day old survivors. However, there were treatment related reductions in the mean body weights of hatchlings and 14-day old survivors in the 600 ppm treatment group. Offspring body weight data can be found in Table 4.

Table 1: Gross pathological observations (adult birds euthanised at test termination)

	Males (ppm)				Females (ppm)
	0	150	300	600	0	150	300	600
Number of birds	14	15	16	16	14	15	16	16
Foot/leg lesions	0	1	2	0	0	0	1	0
Feather loss	2	6	8	4	9	10	11	10
Breast muscle - pale	0	0	0	0	0	0	1	0
Spleen - pale	0	0	0	0	0	0	0	1
Small intestines - areas of hyperemia	1	0	4	0	0	0	0	0
Testes - small (one or both)	6	3	3	4	-	-	-	-
Ovary - regressing	-	-	-	-	0	0	0	1
Not remarkable	7	6	6	8	5	5	5	6

Table 2: Mean adult body weight (g) and weight change (g)

	Males (ppm)				Females (ppm)
	0	150	300	600	0	150	300	600
Week 0	203	194*	196	192*	197	195	197	193
Change week 0-2	2	1	2	0	0	1	2	1
Week 2	205	195*	198	192**	198	196	199	194
Change week 2-4	7	5	5	5	4	4	5	3
Week 4	212	200**	203	197**	202	200	204	197
Change week 4-6	5	4	4	5	2	3	4	3
Week 6	216	203*	207	202**	204	203	209	200
Change week 6-8	1	1	0	1	1	1	0	2
Week 8	218	204**	207*	203**	204	205	208	202
Change week 8-Term	8	3	7	0	42	44	36	34
Term	225	206**	214	204**	245	249	244	236
Total change	23	13	17	12	47	54	57	44

The means for body weights and body weight changes are calculated and rounded separately

*significantly different from control at p <0.05

**significantly different from the control at p <0.01

Table 3: Reproductive performance (normalised as percentage¹)

	Experimental group (ppm)
Reproductive parameter	0	150	300	600
Number of replicates	14	15	16	16
Total eggs laid^2	765	734	669	419
Eggs laid/Maximum laid (%)	76	68	58	36**
Eggs cracked/Eggs laid (%)	0	2	1	0
Viable embryos/Eggs set (%)	94	94	95	89
Live 3 week embryos/Viable embryos (%)	100	100	100	100
Hatchlings/Live 3 week embryos (%)	95	97	92	79**
14 day old survivors/Hatchling (%)	97	93	89	73**
Hatchlings/Eggs set (%)	89	90	87	71*
14 day old survivors/Eggs set (%)	85	83	79	52**
Hatchlings/Maximum set (%)	64	58	48	24**
14 day old survivors/Maximum set (%)	62	54	45*	18**

*significantly different from the control p <0.05

**significantly different from the control p <0.01

¹Values represent pen means for experimental group

²Represents the total number of eggs laid in each group

Table 4: Mean body weight (g) of hatchlings and 14 day old survivors

	0 ppm	150 ppm	300 ppm	600 ppm
Hatchlings
Number	602	586	518	260
Mean (± SD)	6 ± 0	6 ± 0	6 ± 0	5** ± 0
14 day old survivors
Number	580	542	478	194
Mean (± SD)	26 ± 3	25 ± 2	25 ± 2	19** ± 3

The total number of hatchlings weighed may differ from the total number of hatchlings since those found dead were not weighed.

**significantly different from the control p <0.01

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the test, the NOEC for Northern bobwhite exposed to the test material was determined to be 150 ppm based upon the effects seen in the 300 ppm treatment group.

Executive summary:

In a GLP compliant reproductive toxicity to birds study conducted in line with standardised guidelines OECD 206 and EPA 71-4, the reproductive toxicity of the test material to Northern bobwhite quail was determined. The test material was administered by dietary inclusion at 0, 150, 300 and 600 ppm. Under the conditions of the test the NOEC was determined to be 150 ppm based on the effects seen at the 300 ppm treatment level.

Reference 4

Endpoint:

long-term toxicity to birds: reproduction test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 November 1999 to 25 September 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 206 (Avian Reproduction Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 71-4 (Avian Reproduction Test)

Deviations:

no

GLP compliance:

yes

Dose method:

feed

Analytical monitoring:

yes

Vehicle:

no

Details on preparation and analysis of diet:

DIET PREPARATION
- Description and nutrient analysis of basal diet provided in study report: yes
- Preparation of doses: test substance was mixed into a premix that was used for weekly preparation of the final diet.

HOMOGENEITY AND STABILITY OF TEST MATERIAL IN DIET
- How often was homogeneity and stability tested: on day 0 of week 1 and then during weeks 2, 3, 4, 8, 12, 16 and 20.
- When and at what dose levels were samples of treated food analysed for stability and concentration during the study: all dose levels.
- % of nominal: 91.0-98.7 %

Test organisms (species):

Anas platyrhynchos

Details on test organisms:

TEST ORGANISM
- Common name: Mallard
- Age at test initiation (mean and range, SD): 27 weeks
- Weight at test initiation (mean and range, SD): 905-1373 g
- Sexes used: male/female

Limit test:

no

Total exposure duration (if not single dose):

21 wk

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

Sixteen

Control animals:

yes, plain diet

Nominal and measured doses / concentrations:

0, 150, 300 and 600 ppm (nominal)

Details on test conditions:

ACCLIMATION
- Acclimation period: 13 weeks

PEN SIZE AND CONSTRUCTION MATERIALS
- Description: 75 x 90 x 45 cm pens
- Compliant to good husbandry practices: yes
- Caging: one male and one female per pen

NO. OF BIRDS PER REPLICATE
- For treated: 16

TEST CONDITIONS (range, mean, SD as applicable)
- Room temperature: 19.3 ± 1.0 ºC
- Relative humidity (%): 40 ± 15 %
- Photoperiod: 8 hours light per day in the first ten weeks and then 17 hours per day to induce egg laying
- Ventilation: vent up to 15 room air volumes every hour and replace with fresh air

Details on examinations and observations:

MORTALITY / CLINICAL SIGNS
- Time schedule for examinations: daily

BODY WEIGHT
- Time schedule for examinations: at test initiation, weeks 2, 4, 6, 8 and at termination but not during egg laying to prevent adverse effects on egg production.

FOOD CONSUMPTION (if feeding study)
- Time schedule for examinations: weekly
- Remarks: presented as an estimate because it was not possible to measure wasted feed.

PATHOLOGY
- Dose groups that were examined: all
- Remarks: all animals that died or euthanised during the course of study and all surviving animals at termination.

Details on reproductive parameters:

The following parameters were examined per parental pen per week:
- Eggs laid
- Eggs cracked; eggs broken
- Egg abnormalities
- Eggshell thickness or eggshell strength
- Eggs fertile
- Embryos viable
- Normal hatchlings
- 14-day old surviving chicks
- Chick body weight at hatching and 14 days after hatching

Reference substance (positive control):

no

Key result

Duration (if not single dose):

21 wk

Dose descriptor:

NOEC

Effect level:

300 other: ppm

Conc. / dose based on:

test mat.

Basis for effect:

reproductive parameters

Mortality and sub-lethal effects:

No mortalities occurred in the study. Incidental clinical observations were noted, including foot and ankle lesions, feather loss, bill abrasions and lameness. Except for incidental findings, all birds were normal in appearance and behaviour throughout the study. All surviving adults were subjected to gross necropsy following adult termination, findings are reported in Table 1.

There were no apparent treatment-related effects upon adult body weight at any of the concentrations tested (see Table 2).

There were no statistically significant differences between the control group and any treatment group of drakes or between the control group and the 150 ppm and 600 ppm treatment groups of hens. However, the mean body weights of hens in the 300 ppm treatment group were slightly, but significantly greater than the control at week 4, 6 and 8. Since the differences were slight, not concentration responsive, and represented an increase in body weight, the observed differences were not considered biologically meaningful or related to treatment.

Mean food consumption measurements are presented in Table 3. There were no treatment-related effects upon feed consumption at the 150 or 300 ppm test concentrations. However, at the 600 ppm test concentration, there was an increase in feed consumption during the first ten weeks of the study that was statistically significant at each of the ten intervals. As an impact upon energy conversion could not be precluded, the observed increases may have been treatment related.

Effects on reproduction:

There were no treatment-related effects upon reproductive performance at the 150 or 300 ppm test concentrations. Although there were statistically significant reductions in cracked eggs as percentages of eggs laid at all test concentrations, the observed differences were slight. Since the reductions represented improvements in performance, and all treatment group values were comparable to the historical control, they were not considered related to treatment. For any of the other reproductive parameters measured no statistically significant differences between the control and either the 150 or 300 ppm treatment groups. At the 600 ppm test concentration, there were marked, treatment-related, effects upon reproductive performance, including effects upon egg production, fertility and hatchability. When compared to the control group, the observed reduction in egg production was statistically significant. While not statistically significant, there were slight, but treatment-related, reductions in viable embryos as a percentage of eggs set and hatchlings as a percentage of live 3-week embryos. The reductions were further reflected as reductions in both hatchlings and 14-day old survivors as percentages of both eggs set and as statistically significant reductions in both hatchlings as 14-day old survivors as percentages of the maximum number of eggs set (see Table 4).

There were no apparent treatment related effects upon eggshell thickness. There were no apparent treatment related effects upon offspring body weights at the 150, 300 or 600 ppm test concentrations and any differences from the control group were not statistically significant for either the hatchlings or the 14-day old survivors (see Table 5).

Table 1: Gross pathological observations (adult birds euthanised at test termination)

	Males (ppm)				Females (ppm)
	0	150	300	600	0	150	300	600
Number of birds	16	16	16	16	16	16	16	16
Foot/leg lesions	5	11	10	7	14	14	16	12
Air sacculitis	0	0	0	0	0	0	0	1
Spleen - enlarged	1	0	0	0	0	1	0	1
Spleen - mottled	0	0	0	0	1	0	0	1
Small intestines - areas of hyperemia	0	1	0	0	0	2	0	0
Testes - small (one or both)	2	0	1	1	-	-	-	-
Abdominal cavity - egg remnants	-	-	-	-	0	0	0	1
Abdominal cavity - slight egg yolk peritonitis	-	-	-	-	1	1	1	1
Abdominal cavity - egg yolk peritonitis	-	-	-	-	1	1	1	3
Abdominal cavity - slight old egg yolk peritonitis	-	-	-	-	0	1	0	0
Ovary - regressing	-	-	-	-	1	2	1	3
Ovary - cystic follicles	-	-	-	-	1	0	0	2
Ovary - cyst	-	-	-	-	1	0	0	0
Not remarkable	10	4	6	9	2	2	0	3

Table 2: Mean adult body weight (g) and weight change (g)

	Males (ppm)				Females (ppm)
	0	150	300	600	0	150	300	600
Week 0	1163	1204	1129	1202	1033	1060	1074	1018
Change week 0-2	-42	-48	-7	-120	-57	-34	-31	-12
Week 2	1121	1156	1121	1190	976	1027	1043	1006
Change week 2-4	5	27	9	8	3	3	14	16
Week 4	1126	1183	1130	1198	979	1030	1057*	1023
Change week 4-6	22	-7	39	18	24	-1	-3	17
Week 6	1149	1176	1169	1216	1003	1028	1091**	1043
Change week 6-8	-11	-3	1	4	4	-1	-3	-17
Week 8	1138	1174	1171	1221	1006	1027	1088*	1060
Change week 8-Term	17	12	33	-3	126	151	95	32
Term	1155	1185	1204	1218	1132	1178	1182	1092
Total change	-9	-19	75	16	99	118	108	73

The means for body weights and body weight changes are calculated and rounded separately

*significantly different from control at p <0.05

**significantly different from the control at p <0.01

Table 3: Mean feed consumption (g/bird/day)

Weeks	0 ppm	150 ppm	300 ppm	600 ppm
1	60	65	71	83**
2	96	102	99	120**
3	96	112	104	122**
4	101	113	103	128**
5	108	115	114	134**
6	105	126	117	142**
7	105	123	111	143**
8	122	132	121	160**
9	112	127	114	152**
10	120	135	115	152**
11	118	130	113	140
12	151	163	158	166
13	168	187	163	176
14	146	166	140	163
15	166	175	172	173
16	172	177	158	191
17	171	189	172	192
18	188	200	190	203
19	190	199	183	204
20	184	191	189	204
21	189	191	198	201

**significantly different from the control p <0.01

Table 4: Reproductive performance (normalised as percentage¹)

	Experimental group (ppm)
Reproductive parameter	0	150	300	600
Number of replicates	16	16	16	16
Total eggs laid^2	852	750	745	561
Eggs laid/Maximum laid (%)	73	64	64	48**
Eggs cracked/Eggs laid (%)	4	2*	1**	1**
Viable embryos/Eggs set (%)	88	87	81	76
Live 3 week embryos/Viable embryos (%)	99	100	97	98
Hatchlings/Live 3 week embryos (%)	90	92	92	81
14 day old survivors/Hatchling (%)	99	100	99	100
Hatchlings/Eggs set (%)	78	80	72	59
14 day old survivors/Eggs set (%)	77	80	72	59
Hatchlings/Maximum set (%)	53	50	46	24**
14 day old survivors/Maximum set (%)	53	50	46	24**

*significantly different from the control p <0.05

**significantly different from the control p <0.01

¹Values represent pen means for experimental group

²Represents the total number of eggs laid in each group

Table 5: Mean body weight (g) of hatchlings and 14 day old survivors

	0 ppm	150 ppm	300 ppm	600 ppm
Hatchlings
Number	572	538	495	263
Mean (± SD)	37 ± 3	38 ± 2	37 ± 3	38 ± 2
14 day old survivors
Number	568	533	482	261
Mean (± SD)	260 ± 19	278 ± 20	276 ± 20	256 ± 21

The total number of hatchlings weighed may differ from the total number of hatchlings since those found dead were not weighed.

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the test, the NOEC for mallard ducks exposed to the test material was determined to be 300 ppm based upon the effects seen in the 600 ppm treatment group.

Executive summary:

In a GLP compliant reproductive toxicity to birds study conducted in line with standardised guidelines OECD 206 and EPA 71-4, the reproductive toxicity of the test material to mallard ducks was determined. The test material was administered by dietary inclusion at 0, 150, 300 and 600 ppm. Under the conditions of the test the NOEC was determined to be 300 ppm based on the effects seen at the 600 ppm treatment level.

Description of key information

Acute oral toxicity study in the Bobwhite Quail conducted in line with GLP and standardised guideline EPA 71-1; the LD50 value was determined to be 683 mg/kg bw (95 % C.I. 549-818 mg/kg bw).

The dietary toxicity (LC50) of the test material to the mallard duck conducted in line with GLP and standardised guideline EPA 71-2; the LC50 was determined to be >5200 mg/kg diet.

A reproduction study with the Northern bobwhite conducted in line with GLP and standardised guidelines OECD 206 and EPA 71-4; the NOEC was determined to be 150 ppm.

A reproduction study with the Mallard conducted in line with GLP and standardised guidelines OECD 206 and EPA 71-4; the NOEC was determined to be 300 ppm.

Key value for chemical safety assessment

Short-term EC50 or LC50 for birds:

5 200 mg/kg food

Long-term EC10, LC10 or NOEC for birds:

150 mg/kg food

Additional information

In the key GLP compliant acute oral toxicity to birds study conducted in line with standardised guideline EPA 71-1, the acute oral toxicity of the test material to bobwhite quail was determined. The test material was administered by capsule as a single dose, followed by a 15 day observation period, at 0, 400, 800, 1086, 1474 and 2000 mg/kg. Under the conditions of the test the LD₅₀ value was determined to be 683 mg/kg bw (95 % C.I. 549-818 mg/kg bw).

In a supporting GLP compliant acute oral toxicity to birds study conducted in line with standardised guideline EPA 71-1, the acute oral toxicity of the test material to mallard ducks was determined. Under the conditions of the test it was not possible to determine a LD₅₀value because there were no mortalities; the value must be in excess of 50 mg/kg bw, the maximum dose-level at which there were no emetic effects.

In the key GLP compliant short-term dietary toxicity to birds study conducted in line with standardised guideline EPA 71-2, the short-term dietary toxicity of the test material to mallard ducks was determined. The test material was administered by dietary inclusion at 650 1300, 2500 and 5200 ppm. Under the conditions of the test it was not possible to determine a LC₅₀ value because there were only two mortalities at the highest dose level tested. This value must therefore be in excess of 5200 mg/kg diet.

In a supporting GLP compliant short-term dietary toxicity to birds study conducted in line with standardised guideline EPA 71-2, the short-term dietary toxicity of the test material to bobwhite quail was determined. Under the conditions of the test it was not possible to determine a LC₅₀value because of the distribution of the mortalities that occurred; the value appears to be in the region of 5200 ppm, the maximum dose used.

In key GLP compliant reproductive toxicity studies conducted in line with standardised guidelines OECD 206 and EPA 71-4, the reproductive toxicity of the test material to Northern bobwhite quail and mallard duck was determined. The test material was administered by dietary inclusion at 0, 150, 300 and 600 ppm. Under the conditions of the tests the NOEC was determined to be 150 ppm (Northern bobwhite quail) and 300 ppm (mallard).