Glyoxylic acid

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

RCC Ltd - Zelgliweg 1 - 4452 Itingen/Switzerland

Analytical monitoring:

yes

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The study was performed with zebra fish (Brachydanio rerio). The test fish were raised in the RCC Laboratories without any medication. Prior to test start, they were acclimated for one week to the test water and temperature. During holding and acclimatization until one day before the start of the test the fish were fed with a commercial fish diet (Tetra Min(r) Hauptfutter, supplied by Tetra-Werke - Germany). During the last two weeks prior to the test no fish died in the test fish batch and all fish were healthy.
From the acclimated test fish batch, 10 fish were measured at the start of the test. The mean body length of the fish was 3.3 +/- 0.07 cm (Mean +/- SD), the mean body wet weight was 0.24 +/- 0.01 g (Mean +/- SD).

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

96 h

Hardness:

1.25 mmol/L (125 as CaCo3 mg/L)

Test temperature:

21-22 °C during the test period

pH:

The pH values in the test medium and the control ranged during the test period from 6.8 to 7.2 (the pH value after adjustement at each test item application was 7.1).

Dissolved oxygen:

The oxygen concentration was always 7.8 mg/L or higher and thus higher than 60 % oxygen saturation

Nominal and measured concentrations:

200 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- glass aquarium with 5 liters of test medium was used for each treatment
- Aeration: the test medium and the controls were slightly aerated during the test period
- Renewal rate of test solution: during the test the fish were transferred daily into a clean test vessel with freshly prepared test medium
- No. of organisms per vessel: 7
- Biomass loading rate: less than 1 g fish wet weigt per liter

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: at the start of the test and before each test medium renewal, the test medium of nomial 200 mg/L was freshly prepared by completely dissolving 1000 mg (dosing range: 1000.0-1000.5 mg) of the test item in 5 liters of test water using satirring for 15 minutes at room temperature


OTHER TEST CONDITIONS
- Adjustment of pH: with 6.2-6.5 mL of a 1 M sodium hydroxide solution
- Photoperiod: 16-hours light t 8-hours dark period (30 minutes transition)
- Light intensity: 50-500 Lux

Reference substance (positive control):

yes

Remarks:

test water without addition of the test item

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

> 200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 200 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: observations

Details on results:

In the control and in the test medium with the nominal concentration of 200 mg/L (= Glyoxylic acid 100.3 mg/L) all fish survived until the end of the test and no visible abnormalities were observed at the test fish. Therefore, the 96-h NOEC and the 96-h LC0 were determined to be at least 200 (100.3 ) mg/L. The 96-h NOEC and the 96-h LC0 might even be higher than this concentration, but concentration in excess of 200 (100.3) mg/L have not been tested.
The 96-h LOEC, the 96-h LC50 and the 96-h LC100 were clearly higher than 200 (100.3) mg/L. These values could no be quantified due to the absence of toxicity of Glyoxylic acid 50 % at the tested concentration.
No remarkable observation were made concerniong the appearance of the test medium. It was a clear solution throught the entire test duration.

Sublethal observations / clinical signs:

In the analyzed test medium samples from the start and end of the first and last test medium renewal periods the measured test item concentrations ranged between 103 and 114% of the nominal value. Consequently, the test water renewal ensured nearly constant concentration of the test item during the test and the reported biological results are related to the nominal test item and Glyoxylic acid (in brackets) concentration.

Validity criteria fulfilled:

yes

Conclusions:

The 96-hour LC50 in Zebra fish is > 200 mg/L (Glyoxylic acid 50 % ) or > 100.3 mg/L (Glyoxylic Acid).

Executive summary:

The acute toxicity of the test item Glyoxylic acid 50% to zebra fish (Brachydanio rerio) was determined in a 96 -hour semi-static test with a daily test medium renewal according to the EU Commission Directive 92/69/EEC, Part C.1 (1992) and the OECD Guideline for Testing of Chemicals No 203, (1992). A limit test was performed in accordance with the guideline to demonstrate the test item Glyoxylic acid 50% has no toxic effect on the test organisms at the nominal concentration of 200 mg/L and a control.

In the control and in the test medium with the nominal concentration of 200 mg/L Glyoxylic Acid 50% (= 100.3 mg/L Glyoxylic Acid) all fish survived until the end of the test and no visible abnormalities were observed at the test fish.

Therefore, the 96-hour NOEC (highest concentration tested without toxic effects after the exposure period of 96 hours), and the 96-hour LC0 were determined to be at least 200 (100.3) mg/L. the 96-hour NOEC and the 96-hour LC0 might even be higher than this concentration, but concentrations in excess of 200 (100.3) mg/L have not been tested. The 96 -hour LOEC (lowest concentration with toxic effects), the 96-hour LC50 and the 96-hour LC100 were clearly higher than 200 (100.3) mg/L. These values could not be quantified due to the absence of toxicity of Glyoxylic acid 50% at the tested concentration.

Description of key information

the 96-hour NOEC (highest concentration tested without toxic effects after the exposure period of 96 hours), and the 96-hour LC0 were determined to be at least 200 (100.3) mg/L. The 96-hour NOEC and the 96 -hour LC0 might even be higher than this concentration, but concentrations in excess of 200 (100.3) mg/L have not been tested. The 96 -hour LOEC (lowest concentration with toxic effects), the 96-hour LC50 and the 96-hour LC100 were clearly higher than 200 (100.3) mg/L. These values could not be quantified due to the absence of toxicity of Glyoxylic acid 50% at the tested concentration.

Additional information

The acute toxicity of the test item Glyoxylic acid 50% to zebra fish (Brachydanio rerio) was determined in a 96 -hour semi-static test with a daily test medium renewal according to OECD TG 203 (1992) and GLP. A limit test was performed in accordance with the guideline to demonstrate the test item Glyoxylic acid 50% has no toxic effect on the test organisms at the nominal concentration of 200 mg/L and a control.

In the control and in the test medium with the nominal concentration of 200 mg/L Glyoxylic Acid 50% (100.3 mg/L Glyoxylic Acid) all fish survived until the end of the test and no visible abnormalities were observed at the test fish.