reaction mass of Calcium chloride and Sodium chloride

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP published study that followed good scientific practice and contains sufficient detail for interpretation

Justification for type of information:

See attached document

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 222 (Earthworm Reproduction Test (Eisenia fetida/Eisenia andrei))

GLP compliance:

no

Analytical monitoring:

no

Details on sampling:

No data

Details on preparation and application of test substrate:

The culture medium consisted of peaty marshland soil and horse manure wetted with a predetermined volume of tap water resulting in a moisture content of 65 - 70% of the substratum.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

Specimens of E. fetida were obtained from the stock culture in the laboratory. The mean initial mass of each specimen was 177 +/- 32 mg.

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

10 wk

Post exposure observation period:

Survivors of the 100 and 120 mM NaCl treatments were transferred into untreated medium in order to examine the ability of the worms to regain their reproductive capacity.

Test temperature:

20 -30 degrees C

pH:

No data

Moisture:

Moisture content was 65-70% of the substratum.

Details on test conditions:

Plastic bags containing 500 g wet mass of the medium were used, 10 worms being introduced into each bag at the start of the experiments. Worms in the culture media (n = 400) served as controls. Between 20 and 150 worms were used for the different experimental treatments. Experiments were carried out at room temperature (20-30 degrees C) over 10 weeks. The numbers and the live mass of the worms were measured weekly. Cocoons were also counted weekly and removed from the culture bags.

Nominal and measured concentrations:

0 (control), 20, 40, 60, 80, 100, 120, and 180 mM/kg ww
These concentrations are equivalent to:
0, 1.17, 2.34, 3.51, 4.68, 5.84, 7.01 and 10.52 g/kg soil ww
Using the equation provided in EUSES 2.1, the values were converted into mg/kg soil dw (CONVsoil = RHOsoil / (Fsolid soil * RHO solid); with RHO soil = 1700 kg wwt.m-3; RHO solid = 1500 kg.m-3 and Fsolid soil = 0.6):
0, 1325, 2649, 3974, 5299, 6623, 7948, 11922 mg/kg dw

Key result

Duration:

10 wk

Dose descriptor:

LOEC

Effect conc.:

1 325 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: i.e. 20 mM/kg soil

Duration:

10 wk

Dose descriptor:

NOEC

Effect conc.:

3 974 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: i.e. 60 mM/kg soil

Duration:

10 wk

Dose descriptor:

LOEC

Effect conc.:

5 299 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: i.e. 80 mM/kg soil

Details on results:

Eisenia fetida tolerated 20, 40, and 60mM NaCl concentrations without mortality. 80 mM NaCl did not affect lethality significantly, while 100 and 120 mM NaCl resulted in 15 and 70% mortality, repectively. Results on worm growth were not consistent. All the NaCl concentrations used had a deleterious effect on the reproduction of the worms. At the 100 and 120 mM NaCl concentrations, no coccons were found, but when the surviving worms were transferred into a medium without additional NaCl, they regained their normal reproduction capacity.

Validity criteria fulfilled:

not applicable

Conclusions:

The 10 week LOEC (reproduction) for NaCl exposed to the earthworm, Eisenia fetida, is 20mM NaCl per kg soil, which equates to 1325 mg/kg soil dw.

Executive summary:

The earthworm, Eisenia fetida, was exposed to seven concentrations of sodium chloride (NaCl) spiked soil (and control soil) for ten weeks. Worm survival and reproduction was measured. The 10 week NOEC (mortality) was 60mM NaCl per kg soil (which equates to 3974 mg/kg soil dw). All the NaCl concentrations used had a deleterious effect on the reproduction of the worms. The 10 week LOEC (reproduction) for NaCl exposed to the earthworm, Eisenia fetida, is 20mM NaCl per kg soil, which equates to 1325 mg/kg soil dw.

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study was non-GLP, but followed good scientific principles and was decribed in sufficient detail.

Justification for type of information:

See attached document

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

GLP compliance:

no

Specific details on test material used for the study:

Test material (as cited): sodium chloride
Analytical purity: technical grade
Source: Ville de Montreal (QC, Canada)

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

Earthworms were obtained from Vermicomposter (Toronto, Ontario) and were initially used to establish the laboratory cultures. These cultures were maintained at Analex Inc. (Laval, QC, Canada). The worms were maintained in peat moss (pH 6.0 +/- 0.5) supplemented with horse manure, at 20°C and a photoperiod of 16 hours light: 8 hours dark. Adult earthworms (ranging from 300 to 600 mg wet weight) having a well-developed clitellum were used for toxicity tests.
It is unclear what Eisenia species was used. In some section of the original publication, the authors refer to E. fetida and in other to E. andrei.

Study type:

laboratory study

Substrate type:

other: artificial soil (OECD substrate) and natural composted soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

No data

Details on test conditions:

Each test was carried out in quadruplicate, and 6-10 concentrations (on a logarithmic scale) were used per experiment. Dry substrate (250 g of artficial substrate or
200 g of natural composted soil) was prepared and placed in 500 ml plastic containers. Test substances were dissolved in deionized water at defined concentrations before being added to the substrate. pH was not adjusted. Following acclimatization in clean OECD soil (24h), 10 worms were individually washed, weighed, and added to each test chamber. Test chambers were covered with a geotextile membrane and sealed with perforated (3.2 mm) lids. Food was not added. The number of surviving worms was recorded after 7 and 14 days of exposure by hand sorting. At the beginning of the experiment, soils were rehydrated to 75% (w/w) water-holding capacity by uniformly adding 80 ml (with the artficial substrate) or 130 ml (with the composted soil) of solution (NaCl or reference toxicant) or deionized water (control). Treatment groups were compared to the control group and were used to estimate the concentrations at which lethal effects on earthworms would occur following 14 days of exposure.

Reference substance (positive control):

yes

Remarks:

Mercuric chloride (HgCl2; CAS 10112-91-1) and sodium pentachlorophenol (NaPCP; CAS 123333-54-0); Purity: reagent grade

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

1 807 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: artifical soil; geometric mean of three replicate experiments

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

6 500 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: natural composted soil; geometric mean of two replicate experiments

Duration:

14 d

Dose descriptor:

LC10

Effect conc.:

3 079 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: artificial soil: geometric mean of three replicate experiments

Duration:

14 d

Dose descriptor:

LC10

Effect conc.:

8 378 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: natural composted soil: geometric mean of two replicate experiments

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

3 305 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

artificial soil: geometric mean of three replicate experiments

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

12 265 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

natural composted soil: geometric mean of two replicate experiments

Details on results:

Each test was run in quadruplate. For the artificial soil, the test was run three times, while it was run two times for the natural composted soil. No 95% CI is provided for the NOEC or LOEC in the original publication.

For both test (artficial and natural composted soil), the geometric mean of the results obtained with NaCl was calculated from the results of the replicate experiments (expressed in g/L):
** Artificial soil:
NOEC = 5646 mg/L
LOEC = 17926 mg/L
LC10 = 9622 mg/L
LC50 = 10327 mg/L

** Natural composted soil:
NOEC = 10000 mg/L
LOEC = 18000 mg/L
LC10 = 12890 mg/L
LC50 = 18869 mg/L

As the LOEC are higher than the LC10 and as no information is provided regarding how they were obtained, these values are considered unreliable. The results in g/L were then converted into mg/kg dw assuming that both soils (artificial and natural composted soil) have been dried prior to rehydration. According to the material and method section, 80 mL of test solution were used to rehydrate 250 g of dry soil. For the natural composted soil, 130 mL were used to rehydrate 200 g of soil.

Accordingly, the results expressed in mg/kg dw were:
** Artificial soil:
NOEC = 1807 mg/kg dw
LC10 = 3079 mg/kg dw
LC50 = 3305 mg/kg dw

** Natural composted soil:
NOEC = 6500 mg/kg dw
LC10 = 8378 mg/kg dw
LC50 = 12265 mg/kg dw

Results with reference substance (positive control):

See section "Any other information on results incl. tables"

Table 1. Acute toxicity (E. fetida survival) of NaCl and reference toxicants (HgCl2 and NaPCP) in artifical substrate (standard OECD substrate).

Substrate	NOEC in g/L	LOEC in g/L	LC10 (95% CI) in g/L	LC50 (95% CI) in g/L
NaCl	1.0	10.0	3.2 (1.0-10)	3.2 (1.0-1.0)
	10.0	18.0	11.6 (9.5-12.9)	15.3 (13.9-16.6)
	18.0	32.0	24.0 (18.0-32.0)	22.5 (18.0-32.0)
HgCl2	1.0	10.0	1.0 (0.1-10.0)	1.0 (0.1-10.0)
	0.32	0.56	0.33 (0.25-0.39)	0.72 (0.62-0.83)
	0.32	0.56	0.35 (0.28-0.41)	0.65 (0.56-0.74)
NaPCP	1.0	1.8	0.93 (0.56-1.8)	1.6 (1.4-2.0)
	0.18	0.32	0.25 (0.20-0.28)	0.37 (0.33-0.41)
	0.56	1.0	0.42 (0.32-0.56)	0.57 (0.47-0.68)

Each test was run in quadruplate. The experiment was repeated three times. exposure period, 14 days; 95% Cl, 95% confidence intervals; rehydrated (80 mL, i.e., 75% water-holding capacity) artificial substrate.

Table 2. Acute toxicity (E. fetida survival) of NaCl and reference toxicants (HgCl2 and NaPCP) in natural composted soil.

Substrate	NOEC in g/L	LOEC in g/L	LC10 (95% CI) in g/L	LC50 (95% CI) in g/L
NaCl	10.0	18.0	12.4 (10.1-13.9)	17.2 (15.6-18.8)
	10.0	18.0	13.4 (10.0-18.0)	20.7 (18.0-32.0)
HgCl2	0.10	0.32	0.18 (0.11-0.26)	0.75 (0.57-0.98)
	1.0	3.2	4.1 (3.2-10.0)	4.4 (3.5-5.6)
NaPCP	0.10	0.32	0.11 (0.08-0.14)	0.22 (0.18-0.27)
	0.32	0.56	0.42 (0.32-0.56)	0.75 (0.56-1.0)

Each test was run in quadruplate. The experiment was repeated two times. exposure period, 14 days; 95% Cl, 95% confidence intervals; rehydrated (130 mL, i.e., 75% water-holding capacity) artficial soil.

Conclusions:

The mean LC50 from three experiments conducted with the earthworm, E. fetida, using artifical soil (OECD standard soil) and NaCl was 3305 mg/kg dw in a 14-day soil exposure study.

Executive summary:

The mean LC50 from three experiments conducted with the earthworm, E. fetida, using artifical soil (OECD standard soil) and NaCl was 3305 mg/kg dw in a 14-day soil exposure study.

Description of key information

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

Based on three replicate experiments where the earthworm, E. fetida, was exposed for 14-day to NaCl in artifical soil, the LC50(mortality) was determined at 3305 mg NaCl/kg soil dw. In a 10wk experiment, the LOEC(reproduction) of NaCl to E. fetida was determined at 1325 mg NaCl/kg soil dw.

There is no information supporting the fact that calcium chloride should be more toxic than sodium chloride to soil macroorganisms. 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 soil macroorganisms:

3 305 mg/kg soil dw

Long-term EC10, LC10 or NOEC for soil macroorganisms:

1 325 mg/kg soil dw

Additional information

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

Three acute and one chronic toxicity study with soil macroorganisms were available for sodium chloride. Only the key studies are reported in this dataset. All four studies were assigned a Klimish score of 2. In the key chronic study (Fischer & Molnar, 1997), the earthworm, Eisenia fetida, was exposed to seven NaCl concentrations in the soil (and control soil) for 10 weeks. Mortality and reproduction were assessed. The NOEC (based on mortality) was 3974 mg/kg soil dw. All NaCl concentrations used in the chronic study decreased earthworm reproduction, and the LOEC based on reproduction was determined at 1325 mg/kg soil dw. In the key acute toxicity study with the earthworm, E. fetida, the lowest mean LC50 for NaCl was determined to be 3305 mg/kg dw in a series of 14-day soil exposure studies.

Both sodium chloride and calcium chloride are expected to exhibit a toxic effect to aquatic plants due to their impact on osmotic pressure. There is no information supporting the fact that calcium chloride should be more toxic than sodium chloride soil macroorganisms. 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 data on sodium chloride is considered to appropriately reflect the toxicity of the reaction mass of calcium chloride and sodium chloride.