Sodium chlorate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study was conducted before the FIFRA Good Laboratory Practice requirements (40 CFR Part 160) for wildlife studies became effective. But was conducted according to GLP as described in the Federal Register, Vol. 43, No. 247 (1978). The study was performed according to standard protocol EPA OPP 71-1(a).

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Details on preparation and analysis of diet:

- Feeding during test: Grower ration and water were available ad libitum throughout the study.

Test organisms (species):

other: other avian: Anas platyrhynchos (Mallard duck)

Details on test organisms:

- Strain: -
- Supplier: Production flock, Wildlife International Ltd., Easton Maryland.
- Wild caught: no
- Post-hatch transfer time: On day 22 of incubation of the eggs they were transferred to a hatcher and allowed to hatch on dat 26 or 27. Hatchlings
were placed in a brooder until they were 21 days. From day 21 on they were kept in developer units until they were 5 weeks. They were tranferred to
an outside holding pen until the study commenced.
- Age/size/weight/loading: 6 months at study initiation
- Feeding: During brooding the basal diet was Wildlife Uternational Ltd.'s game bird stareter ration. During the growth period, maintenance period,
and throughout the test period, the basal diet was Wildlife international Ltd.'s game bird grower ration. Grower ration and water were available
ad libitum throughout the study.

Post exposure observation period:

- Pretreatment: 2 weeks prior to the test the birds were placed in pens identical to those used for testing to acclimate.

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

- 5 per sex/group

Control animals:

not specified

Nominal and measured doses / concentrations:

- STABILITY OF THE TEST CHEMICAL SOLUTIONS: -
- SAMPLING: -
- MONITORING OF TEST SUBSTANCE CONCENTRATION:-

Details on test conditions:

- Controls: 1 pen with 10 birds was given distilled water only.
- ENDPOINTS ASSESSED: -

- Duration of test/exposure: Ducks were given one single oral dose of sodium chlorate. The animals were observed for 14 days.
- Type of exposure: oral, gastric intubation
- Post exposure period: -
- Vehicle: distilled water
- Concentration in vehicle: Each bird was weighed and concentrtaion in the vehicle was adjusted to the body weight of the animals making sure the
acurate dose was received
- Total volume applied:
- Doses: 398, 631, 1000, 1590 and 2510 mg/kg bw.
- Other procedures: 15 hours prior to oral administration feed was witheld from the animals.

Details on examinations and observations:

CLINICAL OBSERVATIONS AND FREQUENCY:
- Clinical signs: daily
- Mortality: daily
- Body weight: at study initiation, day 3, day 7 and study termination.
- Food consumption: Accurately measured but presented as estimate due to spillage of the birds.
- Water consumption:
- ORGANS EXAMINED AT NECROPSY (MACROSCOPIC AND MICROSCOPIC):
- Macroscopic:
- Microscopic:
- OTHER EXAMINATIONS: -

Duration (if not single dose):

14 d

Dose descriptor:

LD50

Effect level:

> 2 510 mg/kg bw

Basis for effect:

mortality

Results with reference substance (positive control):

REFERENCE SUBSTANCE: -

Further details on results:

NOAEL (NOEL) : 2510 mg/kg bw
ACTUAL DOSE RECEIVED BY DOSE LEVEL BY SEX: as stated in methods. The administered volume was not analysed for the test substance but one dose was adminitered which was prepared according to the weight of the animal just before administration.
- Time of death: -
- Number of deaths at each dose: 0
TOXIC RESPONSE/EFFECTS BY DOSE LEVEL:
- Mortality and time to death: no mortalities
- Clinical signs: no clinical signs
- Body weight gain: see below
- Food/water consumption: see below

dose average body weight food consumption bird/day (g)
mg/kg day 1 3 7 14 1-7 8-14
398 1127 1161 1136 1173 101 126
631 1062 1106 1095 1129 103 105
1000 1097 1147 1139 1164 90 111
1590 1088 1115 1105 1152 74 104
2150 1060 1086 1063 1097 83 107
0 1141 1194 1177 1097 91 121
- Ophthalmoscopic examination: -
- Clinical chemistry: -
- Haematology: -
- Urinalysis: -
- Organ weights: -
- Gross pathology: -
- Histopathology: -
- Other: -

Reported statistics and error estimates:

STATISTICAL METHODS: The maximum likelyhood method was used.

STATISTICAL RESULTS: No deaths occurred no further statistical analysis was performed.

Reference 2

Endpoint:

long-term toxicity to birds: reproduction test

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study generated according to generally valid and internationally accepted testing guideline and performed under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 206 (Avian Reproduction Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Details on preparation and analysis of diet:

- Vehicle, solvent: No
- Procedure: A concentrated premix was made from which further premixes were made for each dose level. Appropriate premixes were mixed with a volume of basal diet overnight and mixed with a Winkworth tumble mixer.

Test organisms (species):

Colinus virginianus

Details on test organisms:

Bobwhite quail (Colinus virginianus)
- Supplier: Monkfield Nutrition, Hertfordshire, UK
- Wild caught: No
- Age/size/weight: approx. 6 months
- Feeding: adults: meal; chicks: chick crumbs
- Feeding during test: Yes

Limit test:

no

Total exposure duration (if not single dose):

154 d

Post exposure observation period:

- Pretreatment: acclimatisation period of approx. 10 weeks. 2 weeks of pretreatment when untreated basal diet is given.

Nominal and measured doses / concentrations:

- Nominal/measured concentrations: 0, 100, 300 and 1000 ppm (measured concentrations were within 80% of the nominal, therefore nominals
are used)
- Diets were analysed on three occasions.

Details on test conditions:

- Test type: Dietary administration
- Housing: For adults tiered cages of stainless steel mesh, measuring approx. 0.38 x 0.39 x 0.25 m, with a drinker and a food hopper and had a
sloping floor with an egg catcher. Chicks were housed separately from adults in floor pens. Additionally infra red lamps were provided as heat
source.
- Number of replicates, individuals per replicate: 20 replicates, each replicate consisted of 1 male and 1 female
- Collection of eggs: eggs were collected daily and stored at 16 +/- 2 °C. At the end of each week eggs were removed from storage and held at
room temperature for at least 12 hours. Then they were transferred to an incubator at 37.5 +/- 1.5 °C and 50-70% relative humidity. On day 21 they were transferred to the hatcher for 2-3 days at 35.5-38.5 °C and 55-75% relative humidity.
- Test temperature: adults: 21 +/- 2 °C, on 3 occasions it rose to 24 °C; chicks: 19.9-24 °C
- Humidity: 45-67%
- Ventilation: 15-20 air changes per our
- Photoperiod in hours:
Adults
Week of test light dark
Start of week 2 to day 3 of week 5 7 17
Day 4 of week 5 to day 5 of week 5 10 14
Day 6 of week 5 to day 7 of week 5 13 11
Start of week 6 to end of week 8 16 8
Start of week 9 to end of week 9 16.5 7.5
Start of week 10 to termination of test 17 7
Chicks: One room was set at 14 hours light and the other erroneously at 16 hours light. Since half of the birds were in one room and the other half in the other (including the control) it was considered not to have an effect on the integrity or outcome of the test.

DURATION OF THE TEST: 2 weeks of pretreatment, 10 weeks pre-egg production period and 12 weeks egg production period.

Details on examinations and observations:

Health, mortality, food consumption, body weight of adults; cracks, abnormalities, egg shell thickness, fertility and hatching of eggs; health,
mortality, body weight, food consumption of chicks.

Duration (if not single dose):

154 d

Dose descriptor:

NOEC

Effect level:

300 other: ppm

Basis for effect:

reproductive parameters

Remarks on result:

other: measured

Effects on reproduction:

Observations on eggs (mean):
Treatment No. eggs % eggs damaged Shell
(ppm) per week/ of eggs laid thickness
female (mm)
0 5.4 7.4 0.22
100 5.7 3.4* 0.23
300 5.4 5.6 0.23
1000 1.9* 5.2 0.24*

Observations on embryos and hatchlings (mean):
Treatment % viable embryos % live 3-week
(ppm) of eggs set embryos of viable embryos
0 95 95
100 92 93
300 91 88*
1000 68* 60*

Treatment % normal hatchlings % normal hatchlings
(ppm) of viable embryos of live 3-week embryos
0 82 86
100 82 88
300 77 86
1000 44* 73*

Survivors (mean):
Treatment % 14 -day % 14-day 14-day
(ppm) survivors of survivors of survivors/
normal hatchlings normal eggs laid female
0 74 48 2.6
100 63 44 2.5
300 80 47 2.5
1000 74 19* 0.4*

Bodyweights of chicks (mean):
Treatment On hatching (g) at day 14 (g)
(ppm)
0 7.1 18.1
100 7.0 17.7
300 7.1 17.6
1000 6.6* 16.9


Chick food consumption (mean):
Treatment Days 0-7 Days 8-14
(ppm) (g/bird/day) (g/bird/day)
0 1.7 4.8
100 2.4 5.2
300 1.9 5.2
1000 3.3 4.8

* Significant difference compared to the control
- Effect data: NOEC = 300 ppm (equal to 31.6 mg/kg bw/d)

Further details on results:

- Mortality: 5 birds were found dead during the study, 1 in the control, 1 at 300 ppm and 3 at 1000 ppm. 2 additional birds were killed in the control
and 1 at 300 ppm because of severe injuries. It was unlikely that this was related to treatment.
- Adult body weight: no effects found
- Adult food consumption: unaffected by treatment
- Eggs laid: At 100 ppm the number of eggs increased compared to the control, at 1000 ppm the number decreased compared to the control.
The percentage of damaged eggs was lower in all treatments than in the control.
- Egg shell thickness: significantly greater at 1000 ppm
- Viable embryos: significantly reduced at 1000 ppm. Additionally the percentage of live 3-weeks embryos of viable embryos was significantly
reduced at 300 and 1000 ppm. The results of the hatching data would suggest that the difference at 300 ppm is not biologically significant. This endpoint is not asked for in OECD Guideline 206 and it is not a true endpoint, it is more an intermediate measurement, therefore this result is not taken
into acount for determination of the NOEC.
- Hatchlings: no treatment-related effect evident in the percentage of normal hatchlings of live 3-week embryos. However, the percentage of normal hatchlings of viable embryos was significantly reduced at 1000 ppm. The percentage of 14-day survivors of eggs laid per replicate was significantly
reduced at 1000 ppm. The percentage of 14-day survivors of normal hatchlings was unaffected by treatment.
- Chick body weight: body weight on hatching was significantly reduced at 1000 ppm. However, there were no treatment-related effects on
body-weight after 14 days.
- Chick food consumption: variable, but did not seem to be treatment-related.
- Chick post mortem: no treatment related effects when examined post mortem.
CONTROL:
- Eggs laid: the percentage of damaged eggs was greater than the suggested range in the guideline. All other parameters were acceptable and it is
possible that the difference is due to the strain of birds used. This endpoint does not belong to the criteria for validity of the test and therefore does not have an impact on the validity.

Reported statistics and error estimates:

Repeated Measures Analysis was used for adult body weight, adult food consumption rate, egg shell thickness, hatched chick weight and chick body weight. Poisson distributed counts was used for eggs laid per treatment, eggs laid per replicate, 14-day survivors per replicate. Logistic regression
was used for eggs damaged of eggs laid, viable embryos of eggs set, live 3-weeks embryos of viable embryos, normal hatchlings of viable embryos, 14-day survivors of normal hatchlings, 14-day survivors of eggs laid.

Validity criteria fulfilled:

yes

Executive summary:

Study title: Sodium chlorate: Assessment to determine the effects on reproduction in the Bobwhite quail (Colinus virginianus)

Guidelines: United States Environmental Protection Agency Pesticide Assessment Guidelines, Subdivision E, Hazard Evaluation: Wildlife and Aquatic Organisms, Series 71-Avian and Mammalian Testing, § 71-4 Avian reproduction test, dated October 1982.

OECD Guideline for testing of chemicals (1984), no 206, entitled "Avian Reproduction Test".

Study No.: K3AK1008

Test item: Sodium chlorate

Batch No.: 1E0103WF

Purity: 99.66 %

Formulation: Technical material

Test species: Bobwhite quail (Colin us virginianus)

Source: Monkfield Nutrition

Test system: Dietary administration.

Treatments: Control (untreated basal diet) and three test item concentrations.

Test item treatment levels: 100 (Group 2),300 (Group 3) and 1000 (Group 4) ppm.

Replicates: 20 replicates per test item treatment and 20 replicates for the control. Each replicate consisting of one male and one female.

Test period: 2 week pre-treatment period, 10 week pre-egg laying treatment period, 12 week egg laying treatment period. Eggs collected over the 12 week period and resulting chicks reared for 14 days.

Results: No treatment related effects were observed in adult bodyweights or food consumption. At termination of the adult phase a higher incidence of liver congestion was seen at post mortem examination in birds treated at 1000 ppm. Statistically significant effects were observed in the following parameters:

Eggs laid (Group 2, increased & 4, decreased)

Eggs laid per female (Group 4 decreased)

Eggs damaged of eggs laid (Group 2 decreased)

Egg shell thickness (Group 4 increased)

Viable embryos (fertile eggs) of eggs set (Group 4 decreased)

Live 3 -week embryos (Day 18 candling) of viable embryos (Groups 3 and 4 decreased)

Normal hatchlings of viable embryos (Group 4 decreased)

14 -day survivors of eggs laid (Group 4 decreased)

14 -day survivors per female (Group 4 decreased)

Chick bodyweights at hatching (Group 4 decreased)

Conclusion: Under the conditions of this study the NOEC was considered to be 300 ppm.

Description of key information

The NOAEL for Mallard ducks and Northern bobwhite quails amounted to 5620 ppm (approx 2500 - 1500 mg/kg bw/d, based on food consumption per day and body weight on day 0 and 5).

NOEC for the chronic study with Bobwhite quail is 300 ppm (equal to 300 mg/kg food and 31.6 mg/kg bw/d).

Key value for chemical safety assessment

Short-term EC50 or LC50 for birds:

2 510 mg/kg food

Long-term EC10, LC10 or NOEC for birds:

300 mg/kg food

Additional information

Two acute studies with Mallard ducks and one with Northern bobwhite quails were found to be valid. Fink, et al. (1990) exposed ducks to a range of concentrations of sodium chlorate by once intubating a solution in distilled water into the crop. The birds were observed for 14 days and no mortality or body weight changes occurred during this period (No Observed Adverse Effect Level (NOAEL) > 2510 mg/kg). Long, et al. (1991) fed 10 day old ducks chicks and Northern bobwhite chicks for a period of 5 days with a range of concentrations of sodium chlorate mixed into the diet with corn oil. The ducks were observed for this period and up till three days after exposure. No mortality or clinical signs of toxicity were observed throughout the test. Body weight and food consumption were not affected. Sodium chlorate is not toxic at the highest concentrations tested. The NOAEL in both studies amounted to 5620 ppm (approx 2500 - 1500 mg/kg bw/d, based on food consumption per day and body weight on day 0 and 5).

One chronic study was found with Colinus virginianus (Bobwhite quail) and was considered valid. Twenty pairs (1 male and 1 female) of 6 months old bobwhite quails per treatment and 20 pairs for the control were selected. First they were pre- treated for 2 weeks, where they received untreated food. Then a period of 10 weeks pre-egg production started in which they were exposed to different concentrations of sodium chlorate. And after this a 12 weeks period of egg production started. The resulting chicks were reared for 14 days. The number of eggs laid was significantly lower at 1000 ppm. The number of eggs laid per female decreased at 1000 ppm and the number of damaged eggs laid was lower at 100 ppm. The percentage of damaged eggs in the control was greater than the suggested range in the guideline. All other parameters were acceptable and it is possible that the difference is due to the strain of birds used. Egg shell thickness increased at 1000 ppm. The percentage of normal hatchlings of viable embryos was significantly reduced at 1000 rpm. The percentage of 14–day survivors of eggs laid per replicate was significantly reduced at 1000 ppm. Body weight on hatching was significantly reduced at 1000 ppm. The percentage of viable embryos was significantly reduced at 1000 ppm. Additionally the percentage of live 3–weeks embryos of viable embryos was significantly reduced at 300 and 1000 ppm. The results of the hatching data would suggest that the difference at 300 ppm is not biologically significant. This endpoint is not required by OECD Guideline 206 and moreover, it is not a true endpoint but an intermediate measurement between egg viability and hatching, therefore this result is not taken into account for determination of the NOEC. Effect data: NOEC = 300 ppm (equal to 300 mg/kg food and 31.6 mg/kg bw/d).