Registration Dossier

Diss Factsheets

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1982
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: well performed study performed before OECD, no GLP stated

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1982
Report date:
2000

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
not specified
Principles of method if other than guideline:
10 daphnia magna neonates (< 24 hours old) were exposed to two concentrations (85 mg/L, 8.5 mg/L) of the test substance in 96 hour static aquatic effect test in order to assess the environmental impact of the test substance. The objectives of this test were (a) to determine if acute exposures to concentrations of the test substance would aaffect daphnids adversely and (b) if appropriate, provide estimates of the 24-, 48-, 72- and 96 hour EC50 values and the highest concentration causing no significant immobility (< 10%) within the period of the test. The daphnids were observed for signs of stress, as well as immobility during the period of exposure to the test substance.
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
2'-methoxyacetoacetanilide
EC Number:
202-131-0
EC Name:
2'-methoxyacetoacetanilide
Cas Number:
92-15-9
Molecular formula:
C11H13NO3
IUPAC Name:
N-(2-methoxyphenyl)-3-oxobutanamide

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no
Details on test solutions:
23 liters of conditoned water were passed through 2.3 g of test substance at 100 mL/minute for 96 hours. The concentration was determined to 85 mg/L (UV).. This was the highest achievable concentration

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Adult daphnia magna were reared within 100 L culturing tanks. The gravid daphnids used to produce the test animals for the study were obtained from rearing tanks. Prior to the study appr. 100 gravid daphnids were transferred by net into two glass bowls containing diluent water and food. After appr. 18 hour in these bowls, all adult daphnids were removed by usng nets and pipettes. A total of 10 daphnid neonates were transferred from the culturing bowls into stainless steel mesh baskets suspended in the exposure solution vessels.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h

Test conditions

Hardness:
no data
Test temperature:
18 - 19 °C
pH:
7.5 - 8.3
Dissolved oxygen:
7.4 - 9.1 mg/L
Salinity:
no data
Nominal and measured concentrations:
8.5 mg/L and 85 mg/L
Details on test conditions:
The acute test was püerformed by placing the test organisms in stainless steel mesh baskets suspended in glass aquaria containing 20 L of exposure solution. each basket was suspended from a small motor that slowly raised and lowered the position of the basket within the test solution. The light/dark cycle of the photoperiod during the test was 16 hours on / 8 hours off with a 20 minute transition period
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
> 85 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 85 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 85 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 85 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 24-, 48-, 72- and 96 hours EC50 value for daphnia magna were eatimated to be < 85 mg/L. The highest tested concentration causing no significant immobility (< 10%) within the period of the test was determined to be 85 mg/L..
The 96 hour EC50 value indicates that, based on this test, the test substance would not be classified according the EU labeling directive and would correspond to a "low concern level" according to the U.S. EPA's assessment criteria.