3- Hydroxy-4-methyoxypyrdine-2-carboxylic acid

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3-hydroxy-4-methoxypyridine-2-carboxylic acid

Cas Number:

210300-09-7

Molecular formula:

C7H7NO4

IUPAC Name:

3-hydroxy-4-methoxypyridine-2-carboxylic acid

Specific details on test material used for the study:

Substance name: X696476
Lot #: XS9-109113-80 (TSN300901)
Purity: 100%

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Study design

Test type:

other: Static-renewal

Water media type:

freshwater

Total exposure duration:

48 h

Test conditions

Hardness:

150 mg CaCO3/L

Test temperature:

19.3 to 20.9°C

pH:

8.3 to 8.5

Dissolved oxygen:

Dissolved Oxygen (new): 8.1 to 9.0 mg/L (95 to 103% sat.)
Dissolved Oxygen (old): 8.5 to 9.1 mg/L (96 to 105% sat.)

Salinity:

Alkalinity: 160 mg CaCO3/L

Conductivity:

349 μS

Nominal and measured concentrations:

Nominal: 0 (control), 0.63, 1.3, 2.5, 5.0, and 10 mg/L
Mean measured:

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 9.53 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobility

Remarks on result:

other: highest concentration tested

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

9.53 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobility and sublethal effects

Remarks on result:

other: highest concentration tested

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

48 h EC50 (Daphnia): >9.53 mg/L
48 h NOEC (Daphnia): 9.53 mg/L

Executive summary:

A definitive test was performed at nominal concentrations 0 (control), 0.63, 1.3, 2.5, 5.0, and 10 mg/L. Five neonates (<24-hours old) were added to each of four test chambers per treatment at the start of the test. The daphnids were observed for immobility and sublethal effects at approximately 24 and 48 hours after test initiation.

Total hardness, total alkalinity, and conductivity were measured in the dilution water at test initiation. Temperature, dissolved oxygen concentration, and pH were measured in all treatment replicates daily. A thermistor probe was located in a surrogate test chamber to continuously record temperature.

All test acceptability criteria were met for this study. Immobilization among control daphnids was 0%, which is below the acceptability limit of 10% as stated in the protocol and the OECD 202 test guideline. The dissolved oxygen concentration at the end of the test was ≥ 8.5 mg/L in control and test substance treatments, higher than the acceptability minimum of 3 mg/L. This study is classified as acceptable and satisfies the guideline requirement for an acute toxicity test with Daphnia magna.

Based on arithmetic and geometric mean measured concentrations, the 24-hour and 48-hour EC50 values were >9.53 and >9.50 mg/L, respectively, the highest concentration tested. The 48 hour NOEC, based on arithmetic and geometric mean measured concentrations, was 9.53 and 9.50 mg/L, respectively, based on the absence of statistically significant immobility and sublethal effects at this, and all lower test substance concentrations.