reaction mass of Calcium chloride and Sodium chloride

Toxicity to birds

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to birds

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was not conducted according to guideline/s and GLP but the report contains sufficient data to permit a meaningful evaluation of study results

Justification for type of information:

See attached document

Reason / purpose for cross-reference:

data waiving: supporting information

Qualifier:

no guideline followed

Principles of method if other than guideline:

House sparrows were dosed orally with NaCl granules (2–3 mm diameter) at 0, 500, 1,500, 2,500, or 3,500 mg/kg.

GLP compliance:

no

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Dose method:

other: dosed orally with NaCl granules/ and NaCl dissolved in MilliQ-filtered water.

Analytical monitoring:

no

Vehicle:

no

Details on preparation and analysis of diet:

Set 1-House sparrows were dosed orally with NaCl granules (2–3 mm diameter)
Set 2-NaCl dissolved in MilliQ-filtered water. Birds were manually restrained and given an oral dose of NaCl solution using a stainless steel gavage tube inserted into the crop.

Test organisms (species):

other: HOUSE SPARROWS (PASSER DOMESTICUS)

Details on test organisms:

Wild house sparrows were captured September through November using mist nets and live traps. Birds (males and females; predominately
juveniles; mean body weight528.160.24 g) were randomly assigned to treatment groups and housed in wire mesh cages under ambient
light conditions, with ad libitum access to fresh water and a wild bird seed mix. They were acclimatized to captivity for at least 1 wk prior to
testing.

Limit test:

no

Total exposure duration (if not single dose):

12 h

Remarks:

Groups of three birds at each dose were anaesthetized with halothane at 1, 3, 6, and 12 hr post exposure

Post exposure observation period:

1, 3, 6, and 12 hr

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

Set 1 (NaCl Granules)-Two house sparrows were exposed at each dosage level except at 4,500 and 5,500 mg/kg, when three sparrows were used.

Set2 (NaCl dissolved in MilliQ-filfiltered water)- Groups of three birds at each dose.

Nominal and measured doses / concentrations:

Set 1 (NaCl Granules)- Using the up-and down method to estimate the lethal dose (Bruce, 1985). Dosages used were 2,000, 2,500,
3,000, 3,500, 4,000, 4,500, and 5,500 mg/kg.

Set2 (NaCl dissolved in MilliQ-filfiltered water)- Birds were randomly assigned to treatment groups consisting of four birds each. Birds in the three treatment groups received 4,000, 6,000, or 8,000 mg/kg NaCl respectively.

Details on test conditions:

Lethal dose estimation Initially, four house sparrows were manually restrained and dosed orally with NaCl granules (2–3 mm diameter) at 3,000 mg/kg. Two of the birds had free access to water, while the other two birds had water withheld for 6 hr postexposure (PE) to simulate potential winter conditions. Birds were monitored for clinical signs of toxicosis, onset of signs, and time to death. Results of the initial exposure were used to select
the subsequent dose, using the up-anddown method to estimate the lethal dose (Bruce, 1985). Dosages used were 2,000, 2,500, 3,000, 3,500, 4,000, 4,500, and 5,500 mg/kg. Water was withheld for 6 hr PE in all cases, and two house sparrows were exposed at each dosage level except at 4,500 and 5,500 mg/kg, when three sparrows were used. Birds were monitored continuously for the first hour, every half hour for the next 7 hr, and then at least every 10 hr until 72 hr PE. Birds that died were immediately necropsied. Sparrows still alive 72 hr PE were euthanized with halothane and then necropsied. The mean lethal dose (LD50) was calculated using the trimmed Spearman-Karber estimate.

In another exposure trial, house sparrows were exposed to NaCl dissolved in MilliQ-filtered water. Birds were manually restrained and given an oral dose of NaCl solution using a stainless steel gavage tube inserted into the crop. Birds were randomly assigned to treatment groups consisting of four birds each. Birds in the three treatment groups received 4,000, 6,000, or 8,000 mg/kg NaCl respectively. Half of the birds in each treatment group were allowed free access to water, whereas the other two birds in each treatment group were water deprived for 12 hr PE and then given free access to water. All birds were monitored as above.

Details on examinations and observations:

Birds that died were immediately necropsied. Sparrows still alive 72 hr PE were euthanized with halothane and then necropsied. The mean lethal dose (LD50) was calculated using the trimmed Spearman-Karber estimate.

Details on reproductive parameters:

Not applicable

Reference substance (positive control):

not specified

Duration (if not single dose):

72 h

Dose descriptor:

LD50

Effect level:

3 000 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: Results indicated an approximate mean lethal dose (LD50) of 3,000–3,500 mg/kg in water-deprived birds,

Duration (if not single dose):

72 h

Dose descriptor:

LD50

Effect level:

8 000 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: House sparrows dosed with a concentrated solution of NaCl generally died at doses of 8,000 mg/kg.

Repellency factors (if applicable):

Not applicable

Mortality and sub-lethal effects:

Clinical signs observed at >/=1,500 mg/kg included rapid onset (,30 min) of depression (indicated by reduced activity and reduced response to visual and auditory stimuli), ataxia, inability to fly or perch, and death.

Effects on reproduction:

Not applicable

Results with reference substance (positive control):

None

Further details on results:

Dose responce study details:
Plasma Na concentrations .200 mmol/l were consistently associated with clinical signs. Pathologic lesions consisted of edema and distension of the caudoventral thin muscled region of the gizzard and were observed 1 hr PE in most birds dosed with >500 mg/kg. Brain Na concentrations in clinically ill sparrows and those that died of NaCl toxicity ranged from 1,297 to 1,615 (mean51,450; SD5115) ppm wet weight or 5,603 to 6,958 (mean56,367; SD5454) ppm dry weight, which differed significantly from control birds. No histologic lesions were observed in brain sections of exposed birds, likely reflecting the acute nature of the exposure. However, fluid accumulation beneath the koilin layer of the gizzard was observed in the majority of birds at high dosage levels. These results indicate that passerines ingesting relatively small numbers of road salt granules or small quantities of highly concentrated NaCl solutions are at risk of sodium poisoning.

Reported statistics and error estimates:

The mean lethal dose (LD50) was calculated using the trimmed Spearman-Karber estimate.

None

Validity criteria fulfilled:

not applicable

Conclusions:

Results indicated an approximate mean lethal dose (LD50) of 3,000–3,500 mg/kg in water-deprived birds, which is similar to mammalian values. House sparrows dosed with a concentrated solution of NaCl generally died at doses of 8,000 mg/kg.

Executive summary:

Wild house sparrows were captured September through November using mist nets and live traps. Birds (males and females; predominately juveniles) were randomly assigned to treatment groups and housed in wire mesh cages under ambient light conditions, with ad libitum access to fresh water and a wild bird seed mix. They were acclimatized to captivity for at least 1 wk prior to testing.

The up-and-down method was used in a pilot study to estimate the lethal oral dose of granular NaCl in wild caught house sparrows. The toxicity of highly concentrated NaCl solution also was investigated. Sparrows were deprived of water for 6 hr postexposure (PE) in an attempt to mimic specific winter conditions. Groups of three birds at each dose were euthanized at 1, 3, 6, and 12 hr PE, and samples were collected for histopathology and brain and plasma electrolyte analyses. Results indicated an approximate mean lethal dose (LD50) of 3,000–3,500 mg/kg in water-deprived birds, which is similar to mammalian values. House sparrows dosed with a concentrated solution of NaCl generally died at doses of 8,000 mg/kg. Clinical signs observed at >/=1,500 mg/kg included rapid onset (,30 min) of depression (indicated by reduced activity and reduced response to visual and auditory stimuli), ataxia, inability to fly or perch, and death in as little as 45 min. Birds that survived for 6 hr usually recovered.

Description of key information

No experimental data are available to assess the toxicity of the reaction mass of calcium chloride and sodium chloride to birds. No information is available for calcium chloride but some information is available for sodium chloride.

In a study on Wild House Sparrows, The 12-hour LD50 for wild house, a mean lethal dose (LD50) of 3000–3500 mg/kg following 12 hours of exposure in water-deprived birds was determined.

There is no information supporting the fact that calcium chloride should be more toxic than sodium chloride to birds. Accordingly, the data on sodium chloride is considered to appropriately reflect the toxicity of the reaction mass of calcium chloride and sodium chloride.

Key value for chemical safety assessment

Short-term EC50 or LC50 for birds:

3 000 mg/kg food

Additional information

No experimental data are available to assess the toxicity of the reaction mass of calcium chloride and sodium chloride to birds. Nevertheless, reliable information is available for sodium chloride (NaCl).

One valid toxicity study (Klimish score = 2) with wild house sparrows was available for sodium chloride. Results indicated an approximate mean lethal dose (LD50) of 3000–3500 mg/kg following 12 hours of exposure in water-deprived birds, which is similar to mammalian values. House sparrows dosed with a concentrated solution of NaCl generally died at doses of 8,000 mg/kg.

Both sodium chloride and calcium chloride are expected to exhibit a toxic effect due to their impact on osmotic pressure. There is no information supporting the fact that calcium chloride should be more toxic than sodium chloride to birds. This is supported by the fact that numerous experimental data found similar LC/EC50 values for other kinds of organisms (including fish, aquatic invertebrates and aquatic algae and cyanobacteria). Accordingly, the LC50 of NaCl determined on the Wild House sparrow is considered as appropriate to characterize the toxicity of the reaction mass to birds.