2-methylpyridine

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

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:

Quantitative assessment of the embryotoxic potential of NSO-heterocyclic compounds using zebrafish (Danio rerio)

Author:

Peddinghaus et al.

Year:

2014

Bibliographic source:

Reproductive Toxicology 33 (2012) 224– 232

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: DIN 38415-6

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD. Fish embryo toxicity (FET) test. Draft OECD guideline for the testing of chemicals; 2006.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

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): 2-Methylpyridine

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Chemical name of vehicle: 100% dimethyl sulfoxide (DMSO; Sigma–Aldrich)
- Concentration of vehicle in test medium: The maximum content of DMSO during the test was below 0.25%.
- Solvent control: In order to exclude adverse effects caused by DMSO a solvent control of 0.25% was used.
- Negative control: Artificial water in the absence of the chemical.
- Positive control: 3.7 mg/L 3,4-dichloroaniline dissolved in millipore water.

Test organisms

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Age at study initiation: The FET is initiated as soon as possible after fertilisation of the eggs and no later than 3 hpf (128-cell stage)
- Selection of eggs: To identify fertilised eggs, a binocular with a minimum magnification of 25×should be used. Freshly spawned eggs exhibit the following structures: The chorion surrounds the perivitelline space, which contains the yolk. The blastodisc is located at the animal pole of the yolk.

BREEDING:
- Method of breeding: Groups of 20, 3-month old zebrafish with a ratio of 3:2 (males:females) were used for egg production. Mating, spawning and fertilisation take place within 30 min after the onset of light in the morning.
- Housing: Spawning trays consisting of a flat basin and a metal net covering to which artificial plants are attached are placed into the aquaria. The artificial plants serve as a breeding stimulant and substrate while the metal net covering prevents the fish from feeding on their own spawn.
- Food type: artificial diets (e.g., TetraMinTM flakes; Tetra, Melle, Germany) and live nauplius larvae of Artemia sp. once daily ad libitum.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Nominal and measured concentrations:

- Nominal concentration: 5 concentrations ranging from ca. 20 mg/L to 200 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 24-well plates
- Type: covered with a gas-permeable foil (Renner, Darmstadt, Germany)
- Material, size, headspace, fill volume: 2 mL freshly prepared test solutions and controls per well.
- No. of organisms per vessel: ten eggs that had reached the 8-cell stadium
- No. of vessels per concentration: two independent replicates with ten embryos per test concentration
- No. of vessels per control: two independent replicates with ten embryos per control

EFFECT PARAMETERS MEASURED:
Evaluation of the test was carried out with an inverted microscope at magnifications of 40× and 100×. After an exposure time of 48 h, lethal endpoints (coagulation of the embryo, non-detachment of the tail, and non-detection of the heartbeat) were recorded

Reference substance (positive control):

yes

Remarks:

3.7 mg/L 3,4-dichloroaniline

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

103.51 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Reported statistics and error estimates:

In order to calculate LC50 values, the results of the FET were used to create concentration-response curves.

Any other information on results incl. tables

Sublethal observations / clinical signs:

The experimental, nominal LC50 (103.51 mg/L) was compared with predicted value (266.89 mg/L) obtained from the ECOSAR program. This was done using the toxicity ratio (TR): LC50predicted/LC50 experimental. The TR value was 2.58.