kresoxim-methyl (ISO);methyl (E)-2-methoxyimino-[2-(o-tolyloxymethyl)phenyl]acetate

Long-term toxicity to fish

Administrative data

Endpoint:

adult fish: sub(lethal) effects

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with analytical monitoring

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)

Deviations:

yes

Remarks:

, exposure period: 28 days

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

methyl (2E)-2-methoxyimino-2-[2-[(2-methylphenoxy)methyl]phenyl]acetate

EC Number:

604-351-6

Cas Number:

143390-89-0

Molecular formula:

C18 H19 N O4

IUPAC Name:

methyl (2E)-2-methoxyimino-2-[2-[(2-methylphenoxy)methyl]phenyl]acetate

Details on test material:

- Name of test material (as cited in study report): Reg.No. 242 009
- Physical state: soild (powder)
- Analytical purity: 94.3% active ingredient
- Batch No.: N 36
- Storage condition of test material: room temperature

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Sampling time: at Day 0, 2, 7, 14, 21, 28

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: One stock solution, containing 1.0 mg/L test compound (nominal), was prepared for all test concentrations by dissolving the respective quantity of the test compound in drinking water. To improve the stability of the test compound in water the pH of the stock solution was adjusted to pH 5 with sulforic acid (approx. 20%). To improve the dilution of the test substance in the test water 1 mg test component was predissolved in 1 ml methanol. This solution in methanol was introduced into the respective quantity of test water while being stirred vigorously.
Aliquot amounts of this stock solution containing 1 mg/L test water were transferred into separate vessels, one for each concentration, and then different quantities of methanol were added to obtain the same methanol content in all test solutions.
- Chemical name of vehicle: Methanol

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Forellenhof Fredelsloh, Trout Breeding, Moring 1, Germany
- Hatched: Nov 1993
- Length at study initiation (mean, range): 5.6 cm, 5.0 – 6.2 cm
- Weight at study initiation (mean, range): 1.5 g, 1.2 – 1.9 g
- Feeding during test: yes
- Food type: Ssniff trout starter FB-50/E size 1, of Ssniff, 59494 Soest, Germany
- Amount, frequency: 4% of the mean body weights on working days daily in 2 portions and on non-working days in one portion. Additionally on working days frozen artemia

ACCLIMATION
- Acclimation period: 2.5 months
- Acclimation conditions: same as test
- Type of food: Ssniff trout starter FB-50/E size 1, of Ssniff, 59494 Soest, Germany
- Amount, feeding frequency: About 1 to 2% of their mean body weight daily in 2 portions on workdays and in one portion on non-working days; additionally they received on workdays frozen artemia.
- Health during acclimation: After arrival in the laboratory the fish were treated prophylactically twice with 0.05 mg/L malachite green chloride and once with 10 mg/L tetracycline hydrochloride for about 24 hours each.
- Mortality during final adaption (ca. 1 week): 0.8%

Study design

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

28 d

Test conditions

Hardness:

2.3 mmol/L

Test temperature:

14 ± 1 °C

pH:

8.1 - 8.3

Dissolved oxygen:

9 -10 mg/L

Nominal and measured concentrations:

Nominal test concentrations: control, 0.004, 0.02, 0.1, 0.5 mg/L
Recovery rate: n.d., -, 79.6, 66.4, 91.3%
n.d. = non-detectable

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, fill volume: glass aquaria in a stainless steel frame, 60 x 35 x 40 cm, 60 L
- Aeration: continuously aerated with oil-free air
- Renewal rate of test solution (flow rate): 10 L/hour/test aquarium
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: drinking water purified over active carbon and aerated
- Culture medium different from test medium: no
- Intervals of water quality measurement: temperature daily, pH and oxygen content twice weekly

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light : 8 hours darkness

EFFECT PARAMETERS MEASURED: mortality daily; toxic signs on each working day; body length and weight were determined at the beginning and at the end of the study

TEST CONCENTRATIONS
- Range finding study: preceding invalid 28-day study was used for selecting the concentrations
- Test concentrations and mortality: at 0.05 and 1.0 mg/L 1/20 fish died. At 0.01 and 0.001 mg/L no mortality occurred. Toxic symptoms were observed in the concentrations 0.05 and 0.1 mg/L for only one day

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.013 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.013 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

behaviour

Effect concentrations 3

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.013 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Details on results:

BODY WEIGHT
- At the end of the study (day 28) no significant differences in the mean body weight between the negative control (5.0 g), solvent control (5.1 g) and the treatment groups 0.004 and 0.02 mg/L (5.0 and 4.8 g) are observed. In the 0.1 mg/L group the mean weight was only 3.1 g. No body weight could be measured in the 0.5 mg/L group since there were no survivors.
- Threshold level for the impairment of the growth parameter body weight was greater than 0.02 mg/L and smaller than 0.1 mg/L.

BODY LENGTH
- At the end of the study (day 28) no significant differences in the mean body length between the negative control (7.7 cm), solvent control (7.7 cm) and the treatment groups 0.004 and 0.02 mg/L (7.6 cm) are observed. In the 0.1 mg/L group the mean weight was only 6.7 cm. No body length could be measured in the 0.5 mg/L group since there were no survivors.
- Threshold level for the impairment of the growth parameter body length was greater than 0.02 mg/L and smaller than 0.1 mg/L.

TOXIC SIGNS
- Compound-related toxic signs were observed in the concentration group 0.1 mg/L in the form of apathy, reduced or no uptake of food and discoloration (dark). Symptoms commenced on day 15 and lasted through day 28 of the study (as single occurrences or combined). No toxic signs were observed in all the other test groups containing test compound and in the controls.
- The threshold level for toxic signs (= symptoms) was greater than 0.02 mg/L and smaller than 0.1 mg/L.

MORTALITY
- Mortalities occurred in the two highest test groups: In the 0.1 mg/L group, starting at day 18 (20%) and with 35% dead fish at day 28 the end of the study. In the 0.5 mg/L group all fish died already on day zero of the study. In the control groups as well as in the lower concentrations (0.004 and 0.02 mg/L) no mortalities occurred. The lowest concentration at which mortalities occurred was 0.1 mg/L.
- The threshold level of lethal effects was greater than 0.02 and smaller than 0.1 mg/L.