Calcium chloride

Toxicity to other aquatic organisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

no analytical monitoring

Qualifier:

according to guideline

Guideline:

other: ASTM. 2006. E729-96 and U.S., EPA. 1993. EPA 600/4-90/027F. Technical Report. Cincinnati, OH.

Principles of method if other than guideline:

- Principle of test: The objective of the present study was to assess the direct acute toxicity of six deicing chemicals to native R. sylvatica larvae as a predictor of their relative toxicity in the environment
- Short description of test conditions: five tadpoles pe r4 replicates in test chambers consisted of glass jars with loosely fitting glass lids to prevent evaporation and allow for sufficient oxygen exchang, filled with two liters of filtered Portage Lake wate. 12:12-h light:dark cycle using full-spectrum lights. Water temperature averaged 20.78 °C (range 19.4–21.88 °C) during all trials.
- Parameters analysed / observed: Larvae were checked every 24 h, with mortality recorded at each interval.

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot: Peladow1 , Dow Chemic, pelleted

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Two liters of filtered Portage Lake water and the appropriate amount of chemical deicer were added to obtain the following 11 nominal test concentrations: 0 (negative control), 0.19, 0.32, 0.54, 0.90, 1.50, 2.40, 3.84, 6.14, 9.83, and 15.73 g/L. The treatment solutions were mixed until the test item was completely dissolved in each test vessel.

Aquatic vertebrate type (other than fish):

frog

Test organisms (species):

Rana sylvatica

Details on test organisms:

TEST ORGANISM
- Common name: wood frog
- Source: palustrine wetland adjacent to a moderately traveled road in Baraga County, Michigan (latitude 46.796 N, longitude 88.390 W)
- Age at study initiation: tadpoles
- Feeding during test: no

ACCLIMATION
- Acclimation conditions (same as test or not): Widely collected egg masses randomly assigned to one of four aerated 78-L glass aquaria containing approximately 50 L of filtered water from Portage Lake, Houghton County, Michigan. The eggs began hatching 5 d later.
- Type and amount of food: The tadpoles were fed ad libitum a 3:1 mixture of TetraFin flake goldfish food (Tetra Werke) and pulverized Purina rabbit chow (Purina Mills) from the time they hatched until they were placed into the test chambers.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

no data

Post exposure observation period:

not applicable

Hardness:

no data

Test temperature:

19.4–21.88 C

pH:

no data

Dissolved oxygen:

no data

Salinity:

no data

Conductivity:

no data

Nominal and measured concentrations:

nominal: 0 (negative control), 0.19, 0.32, 0.54, 0.90, 1.50, 2.40, 3.84, 6.14, 9.83, and 15.73 g/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass jars with loosely fitting glass lids to prevent evaporation and allow for sufficient oxygen exchange.
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Photoperiod: 12:12-h light:dark
- Light intensity: full-spectrum lights

EFFECT PARAMETERS MEASURED: mortality every 24 h

TEST CONCENTRATIONS
- Test concentrations: environmental concentrations of Cl in wetlands and vernal pools resulting from NaCl pollution (0.002–10.3 g/L1)

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

3.98 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 3.46-4.57

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

4.18 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% C.L. 3.69-4.73

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

4.72 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% C.I. 4.08-5.47

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

4.85 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% C.I. 4.16-5.65

Details on results:

no data

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

Survival data were not normally distributed, thus non- parametric statistics were used to examine differences in survival across test concentrations. The proportion of larvae surviving at 96 h among treatments was analyzed using the nonparametric Kruskal–Wallis one-way analysis of variance test. To determine the lowest concentration that had significantly lower survival than in the control, we used a Kruskal–Wallis test with multiple post hoc comparisons. The trimmed Spearman–Karber program (version 1.5) was used to calculate the LC50 estimates using untransformed data for each chemical deicer at 24, 48, 72, and 96 h of exposure. The survival data were pooled for each concentration across replicates when calculating the LC50 value. The program R: A Language and Environment for Statistical Computing was used to perform all statistical analyses with an a level of 0.05.

Validity criteria fulfilled:

not specified

Conclusions:

96h exposure of tadpoles of wood frog to the test material at the concentration range 0.19-15.73 g/L, resulted to an estimated LC50 based on mortality of 3.98 g/L.

Executive summary:

A study was performed exposing tadpoles of Rana sylvatica, to the test material for 96h at the concentration range 0.19-15.73 g/L. Test was conducted by standard guideline ASTM "E729-96" and USEPA 1993 "EPA 600/4-90/027F". No analytical monitoring of the test item concentrations during the test was performed. Results showedan estimated LC50 based on mortality of 3.98 g/L.

Description of key information

A study was performed exposing tadpoles of Rana sylvatica to the test material for 96h. Test was conducted by standard guideline ASTM "E729-96" and US EPA 1993 "EPA 600/4-90/027F". No analytical monitoring of the test item concentrations during the test was performed. Results showed an estimated LC50 (mortality) of 3980 mg/L.