Registration Dossier

Administrative data

Endpoint:
toxicity to other aquatic vertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1980
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: 2e: Study well documented, meets generally accepted scientific principles, acceptable for assessment.
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1980

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
To compare the susceptibility of A.mexicanum and X.laevis to toxicants, the 48 h LC50 was determined for 15 chemical compounds, which have been used in comparative studies before (CANTON &ADEMA 1978).For this purpose groups of 10 animals of each species, 3 to 4 weeks after hatching, were exposed for two days to different concentrations of the test compounds in 1-L standardized medium (Dutch Standard Water 1) in covered glass basins. The compounds were added to the water dissolved in distilled water or, if necessary, in acetone, ensuring that no toxic concentrations of acetone were used. The temperature was kept at 20 ± 1oc and the basins were illuminated following a circadic rhythm. During the experiments the organisms were not fed. The 48 h LC50 values were calculated using the method of LITCHFIELD & WILCOXON (1949).
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
No data.
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
No test surrogate or analogue material was used.

Sampling and analysis

Analytical monitoring:
not specified
Details on sampling:
No data.

Test solutions

Vehicle:
not specified
Details on test solutions:
The compounds were added to the water dissolved in distilled water or, if necessary, in acetone, ensuring that no toxic concentrations of acetone were used.

Test organisms

Test organisms (species):
other: Ambystoma mexicanum and Xenopus laevis
Details on test organisms:
Concerning A. mexicanum, the following procedures were applied to come to a satisfactorial culture method :
a.Cold temperature shock : Both sexes were exposed to a slight increase of water temperature (20 -23°C) during 24 h, followed by a sudden fall in water-temperature (23 - 10-12°C) After a certain period of time, varying from 1 day to two weeks, the water temperature was gradually increased to 20 C.
b.Hormonal stimulation of the female : Females were injected intraperitoneally with different amount of gonadotrophic hormones (Pregnyl(R), Organon 75 I.U., 400 I.U. and 800 I.U.) and subsequently placed with untreated males.
c.Hormonal stimulation of the male : Males were injected intra­peritoneally with 75 I.U. or 400 I.U. of gonadotrophic hormones (Pregnyl(R), Organon) and subsequently brought together with untreated females.
d.Hormonal stimulation of both sexes, involving injection with 75 I.U. of the animals on the same day, or injection of the males with 300 I.U. on two successive days and injection of the females with 600 I.U.Pregnyl(R) on the second day.
For this study 3-year-old animals were used, obtained from the University of Utrecht, The Netherlands.

Spawnings of X.laevis were obtained by injecting the male twice with 300 I.U. Pregnyl(R) on two successive days and the females once with 600 I.U.Pregnyl(R) on the second day. The injections have been made into the dorsal lymph sac, piercing the skin of the thigh and the septum between the lymph sacs of the thigh and the back (OCHsE 1948).

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
No post exposure observation period was done.

Test conditions

Hardness:
No data.
Test temperature:
The temperature was kept at 20 ± 1°C.
pH:
No data.
Dissolved oxygen:
No data.
Salinity:
Tests were performed in freshwater.
Nominal and measured concentrations:
No data.
Details on test conditions:
The basins were illuminated following a circadic rhythm. During the experiments the organisms were not fed.
Reference substance (positive control):
not specified

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
52 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks on result:
other: A. mexicanum
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
52 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks on result:
other: X. laevis
Details on results:
No more data are guven in the publication.
Reported statistics and error estimates:
No data.

Any other information on results incl. tables

No data.

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Conclusions:
To compare the susceptibility of A.mexicanum and X.laevis to toxicants, the 48 h LC50 was determined for 15 chemical compounds, which have been used in comparative studies before (CANTON &ADEMA 1978). For this purpose groups of 10 animals of each species, 3 to 4 weeks after hatching, were exposed for two days to different concentrations of the test compounds in 1-L standardized medium (Dutch Standard Water 1) in covered glass basins. During the experiments the organisms were not fed. The 48 h LC50 values were calculated using the method of LITCHFIELD & WILCOXON (1949) and estimated at for A. mexicanum and at for X. laevis.
Executive summary:

To compare the susceptibility of A.mexicanum and X.laevis to toxicants, the 48 h LC50 was determined for 15 chemical compounds, which have been used in comparative studies before (CANTON &ADEMA 1978). For this purpose groups of 10 animals of each species, 3 to 4 weeks after hatching, were exposed for two days to different concentrations of the test compounds in 1-L standardized medium (Dutch Standard Water 1) in covered glass basins. The compounds were added to the water dissolved in distilled water or, if necessary, in acetone, ensuring that no toxic concentrations of acetone were used. The temperature was kept at 20 ± 1°C and the basins were illuminated following a circadic rhythm. During the experiments the organisms were not fed. The 48 h LC50 values were calculated using the method of LITCHFIELD & WILCOXON (1949) and estimated at for A. mexicanum and at for X. laevis.