Alkaline earth metal and zinc hydroxy(substituted)acetate complexes and alkaline earth metal glyoxylate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

supporting study

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

assessment report

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

> 7 400 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 7 400 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 7 400 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 5 000 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: At all doses tested the animals behave as in the control after 96 h (Swarm behaviour and activity are distinct. The animals use the lower part of the vessel for swimming action and they seldom swim to the surface. After the test all animals are feed immediately).
- LC-values were detected graphically on log-probability-paper.

Sublethal observations / clinical signs:

Table 2: Cumulative mortality [%] at various observation times

time [h]	control	600 [mg/L]	1250 [mg/L]	2500 [mg/l]	5000 [mg/L]	10000 [mg
24	0	0	0	0	0	0
48	0	0	0	0	0	0
72	0	0	0	0	0	14 .3
96	0	0	0	0	0	14.3

Validity criteria fulfilled:

yes

Conclusions:

The test substance is not acute toxic to fish.
LC50 (96h) >7400 mg/L

Executive summary:

A GLP-compliant study according to OECD Guideline 203 was performed in Danio rerio under static conditions. Concentrations of 0, 600 mg/L, 1250 mg/L, 2500 mg/L, 5000 mg/L and 10000 mg/L were tested. Under the conditions of this study the test item was not acute toxic to fish. The LC50 (96 h) was determined to be higher than 7400 mg/L.

The source substance contains the major organic moieties of the target substance. Therefore, this study shows that no acute toxicity to fish can be attributed to the organic moieties of the target substance.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

supporting study

Reason / purpose for cross-reference:

assessment report

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.66 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1.04 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LOEC

Effect conc.:

2.3 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

The estimated 96 h LC50 was 439 mg Zn/L. All sculpin exposed to dissolved 778 mg Zn/L (the highest concentration) died by the ninth day. Mortality at 379 mg Zn/L increased from 46% at 96 h to 85% at 13 d. No mortality was observed at an exposure of 50 mg Zn/L or in the controls. No additional mortality occurred after 13 d through the end of the 30-d test. The LC50 values declined with time to an ILL50 (median incipient lethal level concentrations - the LC50 values derived at the time mortality ceased) of 266 mg Zn/L at 13 d. Mortality at the no-observed-effect concentration of 172 mg Zn/L was statistically similar to the controls. The statistically significant no-observed-effect concentration and lowest-observed- effect concentration were 172 and 379 mg Zn/L, respectively.

Sublethal observations / clinical signs:

The target substance contains 16.5 % Zn ions at the highest. Therefore, the hazard value for Zn ion is converted to the target substance considering a Zn content of 16.5 % as worst-case value.

LC50 (Zn ion) = 0.439 mg/L

LC50 (target substance) = 0.439 mg/L / 0.165 = 2.66 mg/L

NOEC (Zn ion) = 0.172 mg/L

NOEC (target substance) = 0.172 mg/L / 0.165 = 1.04 mg/L

LOEC (Zn ion) = 0.379 mg/L

LOEC (target substance) = 0.379 mg/L / 0.165 = 2.3 mg/L

Conclusions:

The median 96 h lethal zinc concentration (LC50) was 439 µg Zn/L (hardness of 154 mg/L as CaCO3) for feral mottled sculpin (Cottus bairdi), decreasing to a median incipient lethal level of 266 µg Zn/L after 13 d. The statistically significant no observed effect concentration and lowest observed effect concentration were 172 and 379 µg Zn/L, respectively.
This result is also relevant for the target substance, which contains 16.5 % zinc ions.

Executive summary:

The toxicity of zinc to the mottled sculpin (Cottus bairdi), the second most sensitive fish species for which toxicity data are available, was tested. The median 96 h lethal zinc concentration (LC50) was 439 µg Zn/L (hardness of 154 mg/L as CaCO 3) for feral mottled sculpin (Cottus bairdi), decreasing to a median incipient lethal level of 266 µg Zn/L after 13 d. The statistically significant no-observed effect concentration and lowest observed effect concentration were 172 and 379 µg Zn/L, respectively.

This result is also relevant for the target substance, which contains 16.5 % zinc ions. Accounting to the Zn content of 16.5 %, this corresponds to LC50 value of 2.66 mg/L for the target substance. The corresponding NOEC and LOEC values for the target substance (assuming a Zn content of 16.5 %) is calculated to be 1.04 mg/L and 2.3 mg/L, respectively.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 September 2019 - 5 December 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

Adopted: 18 June 2019

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Health Care Inspectorate of the Ministry of Health, Welfare and Sport, Utrecht, The Netherlands

Analytical monitoring:

yes

Details on sampling:

Analysis frequency: in 0-hour and 48-hour fresh solution and 48-hour and 96-hour aged solution.

Vehicle:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Source: The fish were reproduced in the test facility. Their parental generation was introduced from Hangzhou Hunter Biotechnology Inc.
- Length at study initiation (length definition, mean, range and SD): 1.7 cm - 2.0 cm
- Weight at study initiation (mean and range, SD): 0.0538 g - 0.0749 g

ACCLIMATION
- Acclimation period: From hatching, there were not any signs of disease or significant numbers of mortality. The fish are held in water of the quality and under the illumination conditions identical with those used in the test during the acclimation period.
- Acclimation conditions (same as test or not): same as test

FEEDING DURING ACCLIMATION
- Feeding frequency during acclimation: Twice on weekday and one time on weekend until 24 hours before the test was started.

FEEDING DURING TEST
- Food type: Fish were not fed during the period of the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

190 mg/L (as CaCO3)

Test temperature:

22.5 - 22.8 °C

pH:

7.58 - 8.28

Dissolved oxygen:

73.2 - 98.5 % ASV

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass bottles, diameter: 16 cm, height: 26 cm
- Material, size, headspace, fill volume: Glass bottles
- Aeration: Before usage, the water was aerated to achieve the required dissolved oxygen concentration
- Renewal rate of test solution (frequency/flow rate): 48 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: Criterion: loading <0.8 g wet weight fish/L water, total length: 1 - 2 cm

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dilution water was the tap water after being treated with Aquapro Pure Water System.
- Total organic carbon: < 2 mg/L

OTHER TEST CONDITIONS
- Photoperiod: 12 hours light: 12 hours darkness
- Light intensity: 540 - 1000 lux

TEST CONCENTRATIONS
- Range finding study : Yes
- Test concentrations: In a non-GLP range-finding test (Study Number G1923J008A) the test concentrations included 1, 10 and 100 mg/L.
- Results used to determine the conditions for the definitive study: According to the result of the range-finding test, the test was carried out as a limit test at the nominal concentration of 100 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: During the 96-hour exposure period, no visible abnormalities were observed.
- Observations on body length and weight: During the 96-hour exposure period, no visible abnormalities were observed.
- Mortality of control: During the 96-hour exposure period, no deaths were observed

Results with reference substance (positive control):

LC50 (24 h): 257.10 mg/L (95 % c.i.: 232.5 - 284.1 mg/L)

Reported statistics and error estimates:

The test was a limit test, no statistical method was adopted.

Validity criteria fulfilled:

yes

Conclusions:

According to the results of the test and based on the nominal concentration, the 96-hour LC50 of the test item to zebra fish (Danio rerio) was greater than 100 mg/L.

Executive summary:

A fish acute toxicity study was conducted with zebra fish (Danio rerio) over a 96-hour exposure period.

Based on the results of the preliminary test, the definitive test was carried out as a limit test at the nominal concentration of 100 mg/L. A blank control was performed concurrently. Seven fish were used for the test group and the control group, respectively.

According to the results of the test and based on the nominal concentration, the 96-hour LC50 of the test item to zebra fish (Danio rerio) was greater than 100 mg/L. The analytically determined TOC concentration was satisfactorily maintained in the range of 80 - 120% of the nominal TOC concentration.

Description of key information

Key study: OECD 203, GLP, semi-static, Danio rerio, LC50 (96h) > 100 mg/L

Read-Across: WoE, FF6, OECD 203, GLP, static, Danio rerio, LC50 (96h) >7400 mg/L

Read-Across: WoE, Zn ion, Cottus bairdi, 96 h, LC50 = 2.66 mg/L (converted to the target substance taking into account the Zn content of 16.5 %)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

Short-term toxicity study with the herein assessed substance

Xue, 2019

A fish acute toxicity study was conducted with zebra fish (Danio rerio) over a 96-hour exposure period.

Based on the results of the preliminary test, the definitive test was carried out as a limit test at the nominal concentration of 100 mg/L. A blank control was performed concurrently. Seven fish were used for the test group and the control group, respectively.

According to the results of the test and based on the nominal concentration, the 96-hour LC50 of the test item to zebra fish (Danio rerio) was greater than 100 mg/L. The analytically determined TOC concentration was satisfactorily maintained in the range of 80 - 120% of the nominal TOC concentration.

Read-across - FF6

Kuttler, 1998

The test item was tested in a study with the species Danio rerio in according to OECD Guideline 203 and under GLP.

The following EC50 values were obtained:

LC50(24h) >10000 mg/L

LC50(48h) > 10000 mg/L

LC50(72h) > 7400 mg/L

LC50(96h) > 7400 mg/L

 

At all doses tested the animals behave as in the control after 96 h (Swarm behaviour and activity are distinct). The animals use the lower part of the vessel for swimming action and they seldom swim to the surface.

The source substance contains the major organic moieties of the target substance. Therefore, this study shows that no acute toxicity to fish can be attributed to the organic moieties of the target substance.

 

Read-across - Zn ion

Brinkman et al., 2005

The fish species (Cottus bairdi) was exposed to five different zinc concentrations (measured: 778, 379, 172, 94, 50, and < 5 mg dissolved Zn/L) for 30 days. Thereby, the median 96 h lethal zinc concentration (LC50) was 439 µg Zn/L (hardness of 154 mg/L as CaCO3) for feral mottled sculpin (Cottus bairdi), decreasing to a median incipient lethal level of 266 µg Zn/L after 13 d. The statistically significant no-observed-effect concentration and lowest-observed- effect concentration were 172 and 379 µg Zn/L, respectively.

 

This result is also relevant for the target substance, which contains 16.5 % zinc ions. Accounting to the Zn content of 16.5 %, this corresponds to LC50 value of 2.66 mg/L for the target substance. The corresponding NOEC and LOEC values for the target substance (assuming a Zn content of 16.5 %) is calculated to be 1.04 mg/L and 2.3 mg/L, respectively.

Comparison of the read-across results with the result of the OECD 203 conducted with registered substance

The 96-hour LC50 determined for the registered substance in an OECD 203 limit test with zebra fish (Danio rerio) as test species was greater than 100 mg/L. Comparing this result to the LC50 values derived by read-across it is clear that on the one hand the LC50 derived based on the read-across with zinc (2.66 mg/L) would highly overestimate the acut toxicity to fish of the registered substance.