Sodium (S)-lactate

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:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Secondary source and Japanese publication with English abstract, thus little information on the conduct of the experiments available.

Qualifier:

no guideline followed

Principles of method if other than guideline:

Determination of the LC50 of pH to various salmonid species (Oncorhynchus mykiss, Salmo trutta, Salvelinus fontinalis, Salvelinus sp., Oncorhynchus rhodurus × masou) after 24 h exposure.

GLP compliance:

not specified

Analytical monitoring:

yes

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Test type:

not specified

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

ca. 3.83 other: pH

Nominal / measured:

meas. (not specified)

Conc. based on:

other: pH

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

not specified

Conclusions:

The short-term toxic effects of pH (H+ ions) on five fish species after 24 h exposure were investigated. The LC50 (24 h) in the rainbow trout (Oncorhynchus mykiss) is pH 3.83.

Executive summary:

In a 24-h acute toxicity study, rainbow trout (Oncorhynchus mykiss) were exposed to acidity at various measured concentrations (pH measurement), presumably under static conditions. The 24-h LC50 was pH 3.83. Sublethal effects were not reported. Based on the results of this study, acidity can be considered to exhibit adverse effects on rainbow trout on a short time-scale (24 h) at pH of approximately 4 and lower.

This toxicity study is classified as supplementary information in the toxicity evaluation of acids; it does not satisfy the guideline requirement for a short-term toxicity study but can nevertheless be used as supportive data or in a weight-of-evidence approach.

Results synopsis

Test organism: Rainbow trout (Oncorhynchus mykiss)

Test type: Static

LC50: pH 3.83

Endpoint(s) effected: Survival/mortality

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

12 946 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

not specified

Conclusions:

EC50 (96 h) for Lepomis macrochirus = 12946 mg/L.

Executive summary:

In a 96-h acute toxicity study, Lepomis macrochirus was exposed to Sodium chloride. The 96-h LC50 was 12946 mg/L. Based on the results of this study, Sodium chloride would be classified as non-toxic  to Lepomis macrochirus.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.                     

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6 390 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

not applicable

Conclusions:

The LC50 effect for sodium chloride on Pimephales promelas fish is 6390 mg/L.

Executive summary:

In a 96-h acute toxicity study, fathead minnow (Pimephales promelas) were exposed to Sodium chloride at nominal concentrations under static conditions. The 96-h LC50 was 6390 mg/L.  Based on the results of this study, Sodium chloride would not be classified as toxic to Pimephales promelas in accordance with the classification system of the U.S. EPA.

This toxicity study is classified as supplementary and satisfies the guideline requirement for acute toxicity studies on fish.

Results synopsis

Test organism size/age (mean wet weight or length): Pimephales promelas, 1 to 7 days old

Test type: Static

LC50: 6390 mg/L (95 % C.I. = 6020–7070 mg/L)

Endpoint(s) effected: Mortality

 

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

11.33 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: Increased hyperactivity exemplified by erratic movement, loss of reflex and hyperventilation
- Other biological observations: Histological examination revealed that gill architecture was destroyed and gill lamellae were fused. The heart showed deformities including perforation and enlargement. The kidney was greatly deformed and discoloured.
- Mortality of control: None

Sublethal observations / clinical signs:

None

Validity criteria fulfilled:

not specified

Conclusions:

LC50 of O. niloticus fingerlings was determined graphically as 11.33 g/L.

Executive summary:

In a 96-h acute toxicity study, Oreochromis niloticus fingerlings were exposed to Sodium chloride at nominal concentrations of 0, 16, 17, 18, 19, 20 g/L under static conditions.  The 96-h LC₅₀ was determined graphically to be 11.33 g/L. Sublethal effects of increased hyperactivity and histological changes in the gill, heart and kidney were also observed. Based on the results of this study, Sodium chloride would be classified as not toxic to Oreochromis niloticus.

Results Synopsis

Test organism size/age:Oreochromis niloticus fingerlings (11.58 g)

Test Type:Static

LC₅₀: 11.33 g/L             

Endpoint(s) Effected: mortality

 

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

320 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.:

195 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

The LC50 of L(+) lactic acid to Danio rerio was determined to be 195 mg/L (mean measured concentration).

Executive summary:

The acute toxicity of the test substance, a solution of about 80% L(+) lactic acid, to the freshwater fish species Brachydanio rerio was determined according to OECD guideline no. 203 and under GLP. The study was carried out as a semi-static test with daily replacement of the test solutions and with 10 fish for each concentration. The exposure duration was 96 hours. The nominal concentrations tested were 100, 180, 320, 560 and 1000 mg/L. The test substance appeared to be completely dissolved at all concentrations tested (visually assessed). The actual concentrations of L(+) lactic acid were determined enzymatically with a Boehringer test kit. They were between 70 and 77% of nominal just after dosing (average 74%). To test the stability the concentrations of L(+) lactic acid were also analysed just before renewal and were between 56 and 82% of nominal (average 70%).

The results of the test were (as nominal concentrations):

96-h LC₅₀= 320 mg/L

96-h LC₁₀₀= 560 mg/L

96-h NOEC (mortality) = 180 mg/L

96-h LC₅₀= 195 mg/L (mean measured concentration)

The nominal concentrations quoted in this report relate to the test material (a solution of about 80% L(+) lactic acid) as supplied by the sponsor. Toxic effects are probably caused by acidification, since test solutions were not buffered or neutralised.

This information is used in a read-across approach in the assessment of the target substance.For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 6

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

130 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % CL= 100-180

Details on results:

The 24, 48 and 96 hour LC50 values for SY-83 in the 96 hour static toxicity test with rainbow trout (Salmo gairdneri) were 150, 130 and 130 mg/L, respectively. All results were based on the nominal concentrations of 32, 56, 100, 180 and 320 mg/L. The no-effect concentration based on the lack of mortality and abnormal effects after 96 hours of exposure was 56 mg/L. The abnormal effects of mortality, surfacing and/or loss of equilibrium were observed in the 100, 180 and 320 mg/L test concentrations during the 96 hour exposure period.
The effects observed for positive control Antimycin A was within the 95% confidence intervals reported in the literature. An examination of the fish culture and acclimation records for this test indicated that the fish were in good condition for testing.

The dissolved oxygen concentrations ranged from 6.1 to 9.2 mg/L during the test. These values represented 56 and 85% saturation at 12°C, respectively, and were considered adequate for testing. The pH values ranged from 3.5 to 7.3. The pH values decreased with higher test concentrations.
The study was conducted following the intent of the Good Laboratory Practice Regulations and the final report was reviewed by Analytical Bio-Chemistry Laboratories' Quality Assurance Unit. All original raw data was provided to Union Oil Company, with a copy retained at Analytical Bio-Chemistry Laboratories.

Validity criteria fulfilled:

yes

Remarks:

Water quality parameters of temperature, dissolved oxygen and pH were measured throughout the test and were within acceptable limits.

Conclusions:

The toxicity of lactic acid to rainbow trout was measured to be: LC50 (96h) 130 mg/L nominal concentration of test material.

Executive summary:

The acute toxicity of lactic acid to rainbow trout (Oncorhynchus mykiss, fromerly known as Salmo gairdneri) was assessed using the methods outlined by the Committee on Methods for Toxicity Tests with Aquatic Organisms. Water quality parameters of temperature, dissolved oxygen and pH were measured throughout the test and were within acceptable limits. As a method precision check, the rainbow trout were challenged with a reference compound, Antimycin A. The estimated 96 hour LC50 and 95 % confidence limits (C.L.) were within the 95 % confidence limits reported in the literature. Culture and acclimation records indicated that the fish were in good condition for testing. The study was conducted at the following nominal concentrations of lactic acid: 32, 56, 100, 180 and 320 mg/L. Ten fish, with a mean weight of 1.09 (± 0.28) g and a mean standard length of 42 (± 3.4) mm, were exposed to each test concentration and a blank control. The results of the four day static fish toxicity studies on lactic acid and Antimycin A are summarised below. The 24 and 48 hour LC50 values were also determined.

Lactic acid:

LC50 (96 h) = 130 mg/L (95 % CI = 100–180 mg/L)

Antimycin A:

LC50 (96 h) = 4.8 × 10^–5 mg/L (95 % CI = 2.4–7.5 × 10^–5 mg/L)

Furthermore, the results indicate a 96-hour no-observed effect concentration for lactic acid of 56 mg/L, which is based on the absence of mortality and abnormal effects.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 7

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

130 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 85% CL = 100-180

Details on results:

The 24, 48 and 96 hour LC50 values for SY-83 were 140, 130 and 130 mg/L, respectively. All results were based on the nominal concentrations of 56, 100, 180, 320 and 560 mg/L. The no-effect concentration based on absence of mortality and abnormal effects after 96 hours of exposure was 56 mg/L.
An examination of the fish culture and acclimation records for this test indicated that the fish were in good condition for testing. The dissolved oxygen concentrations ranged from 5.6 to 9.0 mg/L during the test. These values represented 64 and 102 % saturation at 22 °C, respectively, and were considered adequate for testing. The pH values ranged from 3.1 to 7.2, with decreasing levels as test concentrations increased.

Results with reference substance (positive control):

The bluegill sunfish were challenged with a reference compound, Antimycin A, to verify method precision. The 96 hour LC50 for bluegill sunfish exposed to Antimycin A was 1.0 × 10-4 mg/L and was within the 95 % confidence intervals reported in the literature.

Validity criteria fulfilled:

yes

Remarks:

Water quality parameters of temperature, dissolved oxygen and pH were measured throughout the test and were within acceptable limits.

Conclusions:

A test of the short-term toxicity of lactic acid to bluegill sunfish resulted in an LC50 of 130 mg/L (nominal).

Executive summary:

The acute toxicity of lactic acid to bluegill sunfish (Lepomis macrochirus) was assessed using the methods outlined by the Committee on Methods for Toxicity Tests with Aquatic Organisms. Water quality parameters of temperature, dissolved oxygen and pH were measured throughout the test and were within acceptable limits. As a method precision check, the bluegill sunfish were challenged with a reference compound, Antimycin A. The estimated 96-hour LC₅₀ and 95 % confidence limits (C.L.) were within the 95 % confidence limits reported in the literature. Culture and acclimation records indicated that the fish were in good condition for testing. The study was conducted at the following nominal concentrations of SY-83: 56, 100, 180, 320 and 560 mg/L. Ten fish, with a mean weight of 0.37 (± 0.15) g and a mean standard length of 24 (± 2.3) mm, were exposed to each test concentration and a blank control. The results of the four day static fish toxicity studies using lactic acid and Antimycin A are summarized below. The 24 and 48 hour LC50 values were also determined.

Lactic acid:

LC₅₀(96 h) = 130 mg/L (95 % CI: 100–180 mg/L)

Antimycin A:

LC50 (96 h) = 1.0 × 10^–4 mg/L (95 % CI: 0.75–1.4 × 10^–4 mg/L)

Furthermore, the results indicate a 96-hour no-observed effect concentration of 56 mg/L, which was based on absence of mortality and abnormal effects.

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reference 8

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % CL = 320-468

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

ca. 320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: No data
- Observations on body length and weight: No data
- Other biological observations: No data
- Mortality of control: No data
- Other adverse effects control: No data
- Abnormal responses: No data
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No data
- Effect concentrations exceeding solubility of substance in test medium: No

Reported statistics and error estimates:

LC50, 95 % confidence interval (CI)

Sublethal observations / clinical signs:

The apparent toxicity of lactic acid to Danio rerio can be explained by the low pH values of the test substance solutions (pH 4.1 and 3.5 at concentrations of 320 and 560 mg/L respectively).

Validity criteria fulfilled:

not specified

Remarks:

Poor documentation, validity cannot be assessed

Conclusions:

The short-term toxicity testing of lactic acid on freshwater fish (Danio rerio) resulted in an LC50 (96 h) of 320 mg/L (nominal), which can be attributed to a pH effect.

Executive summary:

In a 96-h acute toxicity study, zebra fish (Danio rerio) were exposed to L-(+)-lactic acid at nominal concentrations of 0 (control), 320 and 560 mg/L (further information on the number of concentration levels not available) under semi-static conditions. The 96-h LC50was > 320 mg/L. The observed effects can be attributed to a pH effect. The NOEC value, based on mortality effects, was 320 mg/L, respectively. Sublethal effects were not reported. Based on the results of this study, L-(+)-lactic acid would not be classified as hazardous to the aquatic environment according to the CLP Regulation (EC) No 1272/2008.

This toxicity study is classified as supplementary information and does not satisfy the guideline requirement for a fish short-term toxicity study but can nevertheless be used as supportive data or in a weight-of-evidence approach.

Results synopsis

Test organism: Zebra fish (Danio rerio)

Test type: Semi-static

LC50: > 320 mg/L

NOEC: 320 mg/L

Endpoint(s) effected: Survival/mortality

This information is used in a read-across approach in the assessment of the target substance. For details and justification of read-across please refer to the read-across report attached to IUCLID section 13.

Description of key information

Sodium (S)-lactate fully dissociates into Na+ ions and lactate when dissolved in water. The ecotoxicology of Sodium (S)-lactate can be understood in terms of the ecotoxicology of Sodium chloride and lactic acid.

Three studies were used in a weight-of-evidence approach for assessing the effects of Sodium chloride. 96-hour LC50 values of 6390, 12946 and 11330 mg/L were obtained for Pimephales promelas, Lepomis macrochricus and Oreochromis niloticus, respectively. 

In three studies used in a weight-of-evidence approach for assessing the effects of lactic acid on different fish species, the 96-hour LC50 values ranged from 130 to 320 mg/L. However, it should be noted that all observed effects are due to the low pH induced by high concentrations of lactic acid. The theoretical pH shift caused by lactic acid at the lowest identified LC/EC50 of 130 mg/L (= 1.443 mmol/L), considering a pKa of 3.9, would result in a final pH of 3.43. This compares quite well to the measured pH values of 4.1 and 3.5 at test concentrations of 320 and 560 mg/L in a slightly buffered system (Bowmer et al., 1998). Furthermore, lethal effects by acidity in the range of approximately pH 4 could be demonstrated by a published study (Molony, 2001; Ikuta, 1992). Therefore, the effects observed in the available short-term toxicity tests on fish are likely attributed to acidity effects instead of being a toxic effect of the lactate ion/molecule.

The molar ratio to convert toxicity values from lactic acid to sodium (S)-lactate is 1.24, which gives an estimate for the 96-h LC50 for fish of 161.2 mg/L. Given that effects of lactic acid can be attributed to pH effects, the derived LC50 should be regarded as an extreme overestimation of the toxicity of sodium (S)-lactate. Lactate as such is therefore considered not to exert any systemic effects on fish in the tested concentration range of up to 560 mg/L.

Overall, effect values describing the potential toxicity of sodium (S)-lactate are far beyond the limits relevant for classification and labelling. Re-calculated to sodium (S)-lactate, the above effect values would result in an LC50 in excess of 1000 mg/L. Therefore, a key value for chemical safety assessment cannot be identified. Sodium (S)-lactate is not hazardous for fish.