Registration Dossier

Ecotoxicological information

Long-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
long-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The test has been conducted according to US standardardised methods. GLP not specified and the test concentrations were not checked (but the substance is expected to be stable)
Reason / purpose for cross-reference:
reference to same study
Qualifier:
according to guideline
Guideline:
other: US. EPA. 1994. Short-term Methods for estimating the chronic toxicity of effluents and receiving waters to freshwater organisms. 3rd Ed. EPA/600/4-91/002. US. Environmental Protection Agency, Environmental Monitoring System Laboratory, Cincinnati, Ohio
Deviations:
not specified
GLP compliance:
not specified
Analytical monitoring:
no
Details on sampling:
Not applicable
Vehicle:
no
Details on test solutions:
The test material, 3,4'-oxydianiline was prepared from a sample supplied by DuPont Haskell Laboratory. The sample was shipped via courrier to EA's Aquatic Toxicology Laboratory in Sparks, Maryland. Upon receipt, the sample was logged in and assigned EA laboratory accession number AT2-519. Stocks of 3,4'-oxydianiline were prepared each day in moderately hard synthetic freshwater, and these stocks were used to dose the test solutions.
Test organisms (species):
Ceriodaphnia dubia
Details on test organisms:
Ceriodaphnia dubia (water flea) were raised in EA's culture facility using synthetic moderately hard water. the cultures were kept in an environmentally controlled room at 25°C with a 16-hour light/8-hour dark photoperiod. Organisms were fed daily with trout chow/yeat.cereal leaves solution supplemented with algae (S. capricornutum) as described in US EPA (1993) method. Gravid adults were reisolated the evening before the test to ensure that neonates were less than 24 hours old at test initiation. The neonated delected for the test were released within an 8-hour period from the time of reisolation, from broods of eight or more.
Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
7 d
Post exposure observation period:
Not applicable
Hardness:
no data
Test temperature:
25°C +/- 1°C
pH:
6.0 - 9.0
Dissolved oxygen:
> 4.0 mg/l
Salinity:
Not applicable
Nominal and measured concentrations:
Nominal concentrations were: 0 (control), 1.35, 3.2, 7.5, 18, 42 and 100 µg/L
Details on test conditions:
Conductivity: 338 µS/cm +/1 20 µS/cm
Reference substance (positive control):
yes
Remarks:
sodium chloride
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 100 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
immobilisation
Remarks on result:
other: Not calculable
Key result
Duration:
7 d
Dose descriptor:
NOEC
Effect conc.:
18 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
reproduction
Remarks on result:
other: Concentration below the concentration at which a significant difference was observed from the control (p=0.01)
Duration:
7 d
Dose descriptor:
LOEC
Effect conc.:
42 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
reproduction
Remarks on result:
other: lowest concentration with a significant difference from the control (p=0.01)
Duration:
7 d
Dose descriptor:
other: IC25
Effect conc.:
40.1 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
reproduction
Remarks on result:
other: 95% confidence limits: 26.5 - 50.1 µg/L
Details on results:
During the test, the temperature ranged from 24.3 to 25.7 °C, the pH from 7.6 to 8.2 and the oxygen concentrations was measured from 7.3 to 8.2 mg/L.
The conductivity was measured between 291 µS/cm and 349 µS/cm.
Results with reference substance (positive control):
Results with sodium chloride as reference substance:
IC25 = 920 mg/L NaCl.
The acceptable control chart limites are 7.5 - 1207 mg/L NaCl.
Therefore, the sensitivity of the ceriodaphnia is considered as acceptable and the validity criteria is fulfilled.
Reported statistics and error estimates:
Not reported

Results with the chronic definitive test with ceriodaphnia dubia

 Nominal test concentration (µg/L 3,4'-oxydianiline)  48 -h % survival  7 -d % survival  mean young production(neonates/organism +/- SD)
 Control  100  100  30.0 (+/-3.4)
 1.35  100  90  26.8 (+/-7.5)
 3.2  100  100  24.6 (+/-3.4)
 7.5  100  100  26.7 (+/-4.2)
 18  100  100  26.9 (+/-4.5)
 42  100  90  22.2 (+/-5.5)
 100  100  100  4.0 (+/-2.5)
Validity criteria fulfilled:
not specified
Remarks:
sensitivity of the organism is controlled with a reference substance and the results are within the acceptable range concentrations
Conclusions:
The result with 3,4-oxydianiline reproduction toxicity test with Ceriodaphnia dubia could be used for the long term toxicity to aquatic invertebrates: NOEC = 18 µg/L (p=0.01). Therefore, 3,4'-oxydianiline could be considered as very toxic to aquatic invertebrates.
Executive summary:

A chronic toxicity test was conducted with Ceriodaphnia dubia according to US EPA guideline. A preliminary range finding test was performed to define test concentrations in the final test where no significant mortality is obtained (see results in short term toxicity to aqautic invertebrates, McCulloch, 2002). Then the final nominal test concentrations were determined from 1.35 to 100 µg/L in the final reproduction test.

No significant mortality was observed at all these concentrations in the final reproduction test whereas a significant decrease in reproduction (number of neonates/organism) was observed from 42 µg/L (p=0.01). Then the NOEC could be determined at 18 µg/L. An US EPA Guidance (2000) was used for the statistical interpretation of the results and the determination of the alpha level.

Description of key information

A chronic toxicity test was conducted with Ceriodaphnia dubia according to US EPA guideline on the analogue 3,4'-oxydianiline. A preliminary range finding test was performed to define test concentrations in the final test. Then the nominal test concentrations were determined from 1.35 to 100 µg/L in the final reproduction test.

No significant mortality was observed at all these concentrations in the final reproduction test whereas a significant decrease in reproduction (number of neonates/organism) was observed from 42 µg/L (p=0.01). Then the NOEC could be determined at 18 µg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates
Effect concentration:
18 µg/L

Additional information