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Ecotoxicological information

Toxicity to aquatic plants other than algae

Administrative data

Endpoint:
toxicity to aquatic plants other than algae
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Published in peer reviewed literature, minor restrictions in design and/or reporting but otherwise adequate for assessment

Data source

Reference
Reference Type:
publication
Title:
Comparative Chronic Toxicity of Pyridine, α-Picoline, and β-Picoline to Lemna minor L. and Chlorella vulgaris B
Author:
Singh and Chandra
Year:
2005
Bibliographic source:
Bull. Environ. Contam. Toxicol. (2005) 75:482–489

Materials and methods

Test guideline
Qualifier:
no guideline followed
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
2-methylpyridine
EC Number:
203-643-7
EC Name:
2-methylpyridine
Cas Number:
109-06-8
Molecular formula:
C6H7N
IUPAC Name:
2-methylpyridine
Details on test material:
- Name of test material (as cited in study report): α-picoline

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
120 x 15 mm-petri-dish with 100 mL in double strength algal growth medium without EDTA containing different concentrations test substance.

Test organisms

Test organisms (species):
Lemna minor
Details on test organisms:
TEST ORGANISM
- Common name: Duckweed
- Strain: Lemna minor L.
- Source: Collected form pollution free sites. Water samples were taken to confirm that the water bodies were not loden with pollutants.
- Method of cultivation: The duckweed test specimens were selected from the axenic stock culture 24 h before the actual test. Selection criteria were healthy-looking and two fronds of approximately equal size per colony.

ACCLIMATION
- Acclimation period: 4 weeks
- Culture media: double strenght algal growth medium without EDTA

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
14 d

Test conditions

Hardness:
245 ± 14 mg/L
Test temperature:
25 ± 2 °C
pH:
8.1 ± 0.2
Nominal and measured concentrations:
- Nominal concentrations (v/v): 0.00125, 0.0025, 0.005, 0.0125, 0.025, 0.0375, and 0.05%
- Nominal concentrations mg/L: approx. 11.75, 23.5, 47, 117.5, 235, 352.5, and 470 (calculated with the density 0.94 g/cm3)
- Analytical concentrations: not determined
Details on test conditions:
TEST SYSTEM
- Test vessel: 120 x 15 mm-petri-dish
- No. of organisms per vessel: 50 colonies
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3
- Shaking rate: Twice daily by hand

GROWTH MEDIUM
- double strength algal growth medium

OTHER TEST CONDITIONS
- Photoperiod: 12hr light/12 hr dark
- Light intensity and quality: Cool, white and fluorescent. 115 µmol photon / m-2·s-1

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: Protein content was determined in accordance with method described by Bradford (1976)
- Chlorophyll measurement: Total chlorophyll content was determined by acetone (80%) extraction.
- Biomass: determined by the dry weight method.


Results and discussion

Effect concentrationsopen allclose all
Duration:
14 d
Dose descriptor:
IC50
Effect conc.:
ca. 836.6 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
14 d
Dose descriptor:
IC50
Effect conc.:
ca. 780.2 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: Chlorophyll
Duration:
14 d
Dose descriptor:
IC50
Effect conc.:
ca. 554.6 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: protein
Reported statistics and error estimates:
Data were statistically analysed by an overall one-way analysis of variance (ANOVA) and when differences observed were significant, the means were compared by the Tukey-Kramer Multiple Ccomparison Test. IC50 values were graphically estimated.

Applicant's summary and conclusion