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

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

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:

OECD Guideline 222 (Earthworm Reproduction Test (Eisenia fetida/Eisenia andrei))

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

ISO 11268-2 (Effects of Pollutants on Earthworms. 2. Determination of Effects on Reproduction)

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:

no

Test substrate

Vehicle:

yes

Remarks:

deionized water

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Study design

Study type:

laboratory study

Substrate type:

artificial soil

Total exposure duration:

8 wk

Test conditions

Test temperature:

18 to 22°C

pH:

pH at initiation: 5.7 to 5.9
pH at termination: 6.2 to 6.3

Moisture:

Water content at initiation: 32.3% to 33.4% (56.7% to 58.6% of the maximum water holding capacity)
Water content at termination: 32.0% to 34.7% (56.2% to 60.9% of the maximum water holding capacity)

Nominal and measured concentrations:

Nominal: Control, 0.63, 1.25, 2.5, 5.0 and 10 mg/kg soil

Reference substance (positive control):

yes

Remarks:

Luxan Carbendazim 500 FC (Carbendazim, 500 g/L nominal)

Results and discussion

Effect concentrations

Key result

Duration:

56 d

Dose descriptor:

LC50

Effect conc.:

> 10 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: highest concentration tested

Results with reference substance (positive control):

There were statistically significant effects on reproduction at a concentration of 1.30 mg carbendazim/kg soil and higher; the EC50 for reproduction was calculated as 1.32 mg carbendazim/kg soil. The results indicating that the sensitivity of the worms was consistent with the level proposed by the OECD 222 guideline (significant effects between 1 and 5 mg carbendazim/kg soil).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

56-day LC50 (Earthworm): > 10 mg/kg soil

Executive summary:

A 56-day test in treated artificial soil according to OECD 222 was conducted; different concentrations of the test item were incorporated into the soil; 6 treatment groups (5 test item concentrations, control); 4 replicates for the test item treatments, 8 replicates for the control, 10 worms each.

Assessment of adult worm mortality, behavioural effects and biomass development was carried out after 28 days exposure of adult worms in treated artificial soil. Reproduction rate (number of offspring) was assessed after additional 28 days (assessed 56 days after application).

All study validity criteria were met. A slight mortality of up to 5% was found in the test item treatment groups which was not statistically significantly different compared to the control, where 2.5% of the worms died (Fisher´s Exact Test, α = 0.05).

Body weights of the earthworms exposed to the test substance were not statistically significantly different compared to the control up to and including the highest test concentration of 10 mg test item/kg soil, Dunnett´s t-test, α = 0.05).

Statistically significant effects on reproduction were observed at the concentration of 5.0 mg test item/kg only. At all other concentrations tested the reproduction rates were not statistically significantly reduced compared to the control group (Bonferroni-Welch t-test, α =0.05). No behavioural abnormalities were observed in any of the treatment groups and the feeding activity in all the treated groups was comparable to the control.

In an earthworm reproduction and growth study with the test substance, the LC50 was estimated to be greater than 10 mg test item/kg soil. The No Observed Effect Concentration (NOEC) for mortality and weight changes was determined to be the concentration of 10 mg test item/kg soil. The No Observed Effect Concentration (NOEC) for reproduction was determined to be the concentration of 2.5 mg test item/kg soil.