Lime (chemical), hydraulic

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 6, 2007 - September 10, 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

No pH adjustment in test medium

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

TEST MEDIUM
- samples were taken in duplicate of all test solutions and the control
- stored with minimum headspace above solution at ambient temperature in plastic bottles
- sampling time points: at beginning of test and at the end of test immediately after determination of biological and physico-chemical parameters

Vehicle:

no

Details on test solutions:

- see 'Test medium' in table 1
- Evidence of undissolved material (e.g. precipitate, surface film, etc): With increasing test item concentrations, precipitates formed over time. The formation of precipitates is likely the result of the reaction between Calcium hydroxide and Carbon dioxide dissolved in the medium yielding poorly soluble Calcium carbonate. At the end of the test, precipitates were found to be difficult to release from the bottom of the test vessels.
- test item was weighed for each test vessel into a weighboat, added to 10L of temperature adapted test medium directly in the test tank and stirred vigorously for 1 minute. under stirring the pH was measured.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

- common name: rainbow trout
- source: Forellenzucht Trostadt GbR, 98646 Trostadt, Thüringen, Germany
- date of purchase: August 13, 2007
- additional information see 'Holding conditions' in table 1

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

not applicable

Hardness:

232 mg/L CaCO3

Test temperature:

15.0-15.5°C

pH:

7.6-11.1

Dissolved oxygen:

8.4-10.1 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

- see 'Nominal concentrations' in table 1
Nominal and measured concentrations were approximately similar.

Details on test conditions:

- see 'Test medium' and 'Holding conditions' in table 1

EXPOSURE CONDITIONS
− Amount of test solution per test vessel: 10 L
− Depth of test solution in the test vessels: 11.5 cm
− Number of fish per test vessel: 7
− Average length of fish: 4.8 ± 0.6 cm (n = 11)
− Average weight of fish: 1.2 ± 0.5 g (n = 11)
− Fish loading: 0.84 g per L
− Renewal of the test solution during the test period: none
− Feeding: none
− Photoperiod: light/dark - 12 h/12 h
− Light intensity: 100 - 1000 lx; measured: 255 ± 34 (SD) lx
− Temperature (min / max): 15.0 / 15.5 °C
− Aeration: permanent

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

50.6 mg/L

Nominal / measured:

nominal

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: no data
- Other biological observations: at 33.3 mg/L and higher an increased mucus production was observed. At 50 and 75 mg/L (initial pH 11.1) all fish showed whitish discoloration of the fins, probably due to severe corrosion.
- Mortality of control: no
- Other adverse effects control: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: the measured Ca concentrations were much below the nominal concentrations, due to the high concentration of Ca from CaCl2 already present in the test medium, and due to the reaction of the test item with CO2 to poorly soluble CaCO3, thus forming precipitates. However, measurement of Ca after acidification at the end of the test resulted in a recovery of 98% (58-122%).
- Initial pH values: 7.8 (control), 9.6 (14.8 mg/L), 9.9 (22.2 mg/L), 10.4 (33.3 mg/L), 10.8 (50 mg/L) and 11.1 (75 mg/L).

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

- probit analysis using linear maximum likelihood regression used to calculate LC50 values (statistical software package: ToxRat Professional 2.09 )
- polynomial regression analysis used to correlate biological effects with initial pH values (Microsoft Excel, 2003)

Validity criteria fulfilled:

yes

Remarks:

Mortality in the control: 0%. Dissolved oxygen concentration in control and test vessels: ≥84,8%.

Conclusions:

A clear concentration-response relationship was observed.
The biological findings were closely related to the initial pH of the test solutions. Therefore the initial pH is considered to be the main reason for the effects of the test item on the test organisms.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: Biological test method: Acute lethality test using Threespine stickleback (Gasterosteus aculeatus). Environment Canada, Ottowa, Ontario. Report EPS 1/RM/10. July, 1990 (Including March 2000 amendments).

Deviations:

not specified

Principles of method if other than guideline:

96h bioassay in natural seawater.

GLP compliance:

not specified

Analytical monitoring:

no

Details on sampling:

Water quality was measured daily (temperature, dissolved oxygen, salinity, pH).

Vehicle:

no

Details on test solutions:

Test solutions were prepared for the samples in natural seawater, aerated for 30 min, and initial water quality was measured.

Test organisms (species):

Gasterosteus aculeatus

Details on test organisms:

TEST ORGANISM
- Common name: Threespine stickleback
- Source: Lawrencetown, NS
- Mean wet biomass: 0.33 g +/- 0.12, N=20
- Fish were randomly introduced into test vessels.

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

not applicable

Hardness:

no data

Test temperature:

no data

pH:

7.93 (at control) - 10.51 (at highest test dose)

Dissolved oxygen:

no data

Salinity:

2.8-3.0%

Nominal and measured concentrations:

Nominal concentrations: 0, 32, 100, 320, 1000, 3200 mg/L

Details on test conditions:

Ten fish were randomly introduced into 20 L of each test concentration. The test was checked for mortalities frequently the first day, then once a day thereafter. Any dead fish were removed.

Reference substance (positive control):

yes

Remarks:

phenol

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

457 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Lime

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% Cl: 262 - 785 mg/l

Details on results:

The pH was 7.91-7.94 in the control, but reached 10.40-10.61 in the 3200 mg/L dose group. There was no mortality in the control or in treatments up to 100 mg/L.
At 320 mg/L: 50% mortality, at 1000 mg/L: 70% mortality and at 3200 mg/L all fish died.

Results with reference substance (positive control):

A monthly reference toxicant test conducted with phenol ensured that normal operating conditions were maintained and that the population of fish used was of normal sensitivity.

Reported statistics and error estimates:

The NOEC was approximated from the concentrations resulting in <=10% mortality in fish.

Validity criteria fulfilled:

not specified

Conclusions:

In the current test with threespine stickleback, the 96h-LC50 for hydrated lime was 457 mg/L. Based on pH values measured at t=0 this is equivalent to 10.47 (10.26-10.52) pH units.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

6 February 2010 to 12 March 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test item did not form a solution using conventional methods such as ultrasonication and high shear mixing. In view of the difficulties associated with the evaluation of aquatic toxicity of poorly water soluble test items, a modification of the standard method for the preparation of aqueous media was performed. An approach endorsed by several important regulatory authorities in the EU and elsewhere (ECETOC 1996 and OECD 2000), is to expose organisms to a saturated solution of the test item in cases where the test item is of high purity and is poorly soluble in water and in the permitted auxiliary solvents and surfactants. Using this approach, a saturated solution was prepared by stirring an excess (50 mg/L) of test item with dechlorinated tap water for 48 hours at approximately 14 °C, then removing the undissolved test item by filtration through a pre-conditioned filter (0.2 µm) to give a saturated solution.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Source: Brow Well Fisheries Limited, Hebden, near Skipton, Yorkshire, UK
- Age at study initiation (mean and range, SD): Juvenile
- Length at the end of the definitive test (length definition, mean, range and SD): 4.3 cm (mean, sd = 0.2)
- Weight at the end of the definitive test (mean and range, SD): 0.85 g (mean, sd = 0.16)
- Feeding during test: No

ACCLIMATION
- Acclimation period: From 24 February 2010 to 8 March 2010
- Acclimation conditions (same as test or not): Fish were maintained in a glass fibre tank with a "single pass" water renewal system. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. The water temperature was controlled at approximately 14 °C with a dissolved oxygen content of greater than or equal to 10.1 mg O2/L.
- Type and amount of food: The stock fish were fed commercial trout pellets which was discontinued 24 hours prior to the start of the definitive test.
- Health during acclimation (any mortality observed): There was zero mortality in the 7 days prior to the start of the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

Not applicable

Hardness:

Approximately 140 mg/L as CaCO3

Test temperature:

12 - 15 °C

pH:

7.5 - 8.5

Dissolved oxygen:

10.0 - 11.9 mg O2/L (% air saturation value 97% - 116%)

Salinity:

Not determined

Nominal and measured concentrations:

Nominal concentration: 100% v/v saturated solution of calcium carbonate (nano)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 20 L glass exposure vessels
- Aeration: The test vessels were aerated via narrow bore glass tubes.
- Renewal rate of test solution (frequency/flow rate): A semi-static test regime was employed in the test involving a daily renewal of the test preparations to ensure that the concentrations of the test item remained near nominal and to prevent the build up of nitrogenous waste products.
- No. of organisms per vessel: 7 fish/ vessel
- No. of vessels per concentration (replicates): 2 replicates
- No. of vessels per control (replicates): 1 control vessel
- Biomass loading rate: 0.30 g bodyweight/litre

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Laboratory tap water was dechlorinated by passage through an activated carbon filter and partly softened giving water with a total hardness of approximately 140 mg/L as CaCO3. After dechlorination and softening the water was passed through a series of computer controlled plate heat exchangers to achieve the required temperature.
- Total organic carbon: 1.018 mg/L (average)
- Chlorine: Average free chlorine = 0.248 mg/L; Average total chlorine = 0.307 mg/L
- Alkalinity: pH = 7.624 (average)
- Conductivity: 386.192 µS/cm at 20 °C (average)
- Culture medium different from test medium: No
- Intervals of water quality measurement: The water temperature, pH and dissolved oxygen concentrations were recorded daily throughout the test.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods

EFFECT PARAMETERS MEASURED: Any mortalities and sub-lethal effects of exposure were recorded at 3, 6, 24, 48, 72 and 96 hours after the start of exposure. The criteria of death were taken to be the absence of both respiratory movement and response to physical stimulation.

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: In the range-finding test fish were exposed to a single test concentration of 100% v/v saturated solution. A single concentration was used as results from the range-finding test for the Acute Toxicity to Daphnia magna test (Harlan Laboratories Ltd. Project Number 2974/0013) indicated toxicity was not expected at this concentration. The test item was prepared as a saturated solution.
- Results used to determine the conditions for the definitive study: There were no sub-lethal effects of exposure during the range-finding test.
The results showed no mortalities at the test concentration of 100% v/v saturated solution.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: zero mortalities and the absence of any sub-lethal effects of exposure

Details on results:

There were no mortalities in 14 fish exposed to a test concentration of 100% v/v saturated solution for a period of 96 hours. There were no sub-lethal effects of exposure observed in the fish.
There were no mortalities or sub-lethal effects seen in the control vessel.
The test preparations were observed to be clear, colourless solutions throughout the duration of the test.

Sublethal observations / clinical signs:

Table 1: Physico-chemical measurements

Nominal Concentration (% v/v saturated solution)	Time (Hours)
	0 Hours (Fresh Media)				24 Hours (Old Media)				24 Hours (Fresh Media)
	pH	mg O2/l	%ASV*	TºC	pH	mg O2/l	%ASV*	T°C	pH	mg O2/l	%ASV*	T°C
Control	7.8	10.9	104	13	8.3	10.6	98	12	7.7	10.6	103	14
100 R1	8.4	10.0	97	14	8.1	10.4	101	14	8.3	10.4	101	14
100 R2	8.5	10.1	98	14	8.1	10.4	101	14	8.3	10.4	101	14

 

Nominal Concentration (% v/v saturated solution)	Time (Hours)
	48 Hours (Old Media)				48 Hours (Fresh Media)				72 Hours (Old Media)
	pH	mg O2/l	%ASV*	TºC	pH	mg O2/l	%ASV*	T°C	pH	mg O2/l	%ASV*	T°C
Control	8.2	10.8	103	13	7.5	10.3	98	13	8.2	10.6	101	13
100 R1	8.2	10.7	104	14	8.1	10.3	100	14	8.4	11.0	107	14
100 R2	8.2	10.7	104	14	8.0	10.3	100	14	8.5	11.9	116	14

 

Nominal Concentration (% v/v saturated solution)	Time (Hours)
	72 Hours (Fresh Media)				96 Hours (Old Media)
	pH	mg O2/l	%ASV*	TºC	pH	mg O2/l	%ASV*	T°C
Control	7.7	11.3	110	14	8.3	10.4	99	13
100 R1	8.4	10.9	108	15	8.3	10.4	101	14
100 R2	8.4	11.9	118	15	8.3	10.4	101	14

*= Dissolved oxygen concentration expressed as a percentage of Air Saturation Value

R₁and R₂= Replicates 1 and 2

Validity criteria fulfilled:

yes

Remarks:

All the validity criteria were satisified.

Conclusions:

The acute toxicity of calcium carbonate (nano) to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated and gave a 96-Hour LC50 of greater than 100% v/v saturated solution. Correspondingly the NOEC was 100% v/v saturated solution.
This study showed that there were no toxic effects at saturation.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
Common functional groups/mechanism of action

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Target: Lime (chemical), hydraulic [CAS 85117-09-5; See section 1.2 for information on purity.
Source: calcium dihydroxide [CAS 1305-62-0; EC 215-137-3] 98.2%

3. ANALOGUE APPROACH JUSTIFICATION
In the environment, lime substances rapidly dissociate or react with water. These reactions, together with the equivalent amount of hydroxyl ions set free when considering 100mg of the lime compound (hypothetic example), are illustrated below:
Ca(OH)2 <-> Ca2+ + 2OH-
100 mg Ca(OH)2 or 1.35 mmol sets free 2.70 mmol OH-
Ca(OH)2 + Ca2SiO4 + CaCO3 + 3 H2O <-> 4Ca2+ + SiO2 + CO2 + 8OH-
100 mg lime (chemical) hydraulic or 0.27 mmol sets free 2.16 mmol OH-
It has to be noted that CO32- is not expected to directly release two hydroxyl ions under most environmental conditions (depends on CO2 concentrations and pH) and this is therefore a worst case assumption.
From these reactions it is clear that the effect of lime (chemical) hydraulic will be caused either by calcium or hydroxyl ions. Since calcium is abundantly present in the environment and since the effect concentrations are within the same order of magnitude of its natural concentration, it can be assumed that the adverse effects are mainly caused by the pH increase caused by the hydroxyl ions. Furthermore, the above mentioned calculations show that the base equivalents are within a factor 2 for lime (chemical) hydraulic and calcium hydroxide. As such, it can be reasonably expected that the effect on pH of lime (chemical) hydraulic is comparable to calcium hydroxide for a same application on a weight basis. Consequently, read-across from calcium hydroxide to lime (chemical) hydraulic is justified.

4. DATA MATRIX
Source: No studies available
Target: 96h LC50 = 50.6 mg/L (rainbow trout); 96h LC50 = 457 mg/L (threespine stickleback)

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

50.6 mg/L

Nominal / measured:

nominal

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
Common functional groups/mechanism of action

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Target: Lime (chemical), hydraulic [CAS 85117-09-5; See section 1.2 for information on purity.
Source: calcium dihydroxide [CAS 1305-62-0; EC 215-137-3] agricultural grade, purity not stated

3. ANALOGUE APPROACH JUSTIFICATION
In the environment, lime substances rapidly dissociate or react with water. These reactions, together with the equivalent amount of hydroxyl ions set free when considering 100mg of the lime compound (hypothetic example), are illustrated below:
Ca(OH)2 <-> Ca2+ + 2OH-
100 mg Ca(OH)2 or 1.35 mmol sets free 2.70 mmol OH-
Ca(OH)2 + Ca2SiO4 + CaCO3 + 3 H2O <-> 4Ca2+ + SiO2 + CO2 + 8OH-
100 mg lime (chemical) hydraulic or 0.27 mmol sets free 2.16 mmol OH-
It has to be noted that CO32- is not expected to directly release two hydroxyl ions under most environmental conditions (depends on CO2 concentrations and pH) and this is therefore a worst case assumption.
From these reactions it is clear that the effect of lime (chemical) hydraulic will be caused either by calcium or hydroxyl ions. Since calcium is abundantly present in the environment and since the effect concentrations are within the same order of magnitude of its natural concentration, it can be assumed that the adverse effects are mainly caused by the pH increase caused by the hydroxyl ions. Furthermore, the above mentioned calculations show that the base equivalents are within a factor 2 for lime (chemical) hydraulic and calcium hydroxide. As such, it can be reasonably expected that the effect on pH of lime (chemical) hydraulic is comparable to calcium hydroxide for a same application on a weight basis. Consequently, read-across from calcium hydroxide to lime (chemical) hydraulic is justified.

4. DATA MATRIX
Source: No studies available
Target: 96h LC50 = 50.6 mg/L (rainbow trout); 96h LC50 = 457 mg/L (threespine stickleback)

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

457 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Lime

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% Cl: 262 - 785 mg/l

Description of key information

Klimisch 1 study: 96h-LC50 = 50.6 mg/L for calcium dihydroxide and this for the freshwater fish rainbow trout (Egeler et al., 2007)

Klimisch 2 study: 96h-LC50 = 457 mg/L for calcium dihydroxide and this for the marine species Gasterosteus aculeatus (threespine stickleback) (Locke et al., 2009)

Klimisch 1 study: 96-h LC50 > 100 %v/v saturated solution for calcium carbonate (nano) using Oncorhynchus mykiss (rainbow trout) (Priestly, 2010)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

50.6 mg/L

Marine water fish

Marine water fish

Effect concentration:

457 mg/L

Additional information

The short-term toxicity study with the freshwater fish rainbow trout (Egeler et al., 2007) was executed according to OECD 203, resulting in a Klimisch 1 score. The biological findings (LC50 = 50.6 mg/L) were closely related to the initial pH of the test solutions. Therefore the initial high pH is considered to be the main reason for the effects of the test item on the fish.

The short-term toxicity study with the marine species Gasterosteus aculeatus Linnaeus (threespine stickleback) (Lockeet al., 2009) was well described and a dose-response relationship was established (LC50 = 457 mg/L). However, the study was not carried out according to GLP, resulting in a Klimisch 2 score.

The acute toxicity to fish of calcium carbonate (nano) was assessed in a study performed according to OECD TG 203 under GLP (Priestly, 2010). In this study Oncorhynchus mykiss (rainbow trout) were exposed to a 100 %v/v saturated solution of calcium carbonate. No mortalities or adverse effects were noted at the concentration tested. Hence the 96-h LC50 for calcium carbonate (nano) was found to be >100% v/v saturated solution and the NOEC was 100% v/v saturated solution.

The concentration of calcium carbonate (nano) that might cause acute toxicity is therefore greater than the maximum solubility of calcium carbonate in water.

Based on the results of the studies performed on calcium dihydroxide and calcium carbonate, it may be concluded that the acute toxicity to fish of grades of lime (chemical) hydraulic containing up to 40% calcium carbonate will be driven by the calcium dihydroxide content and that the results available for calcium dihydroxide represent the worse-case for all grades of lime (chemical) hydraulic.