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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:
1981-06-23
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The authors tested acute toxicity in Daphnia magna Straus after exposure to 4-chloro-benzotrichloride according to DIN 38 412 Part 11, which is similar to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). No data on the GLP procedure was reported but validity criteria were partially fulfilled. Thus we consider this study to be a Klimisch 2d study since it is in accordance with national standard methods with acceptable restrictions.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009
Reference Type:
study report
Title:
Unnamed
Year:
1981
Report Date:
1981
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report Date:
1987

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
other: DIN 38 412 Part 11
Deviations:
no
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
yes
Remarks:
24h exposure in stead of 48h; test substance concentration was not checked
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): p-Chlorobenzotrichloride
- Date of delivery: 1980-10-21

No more data available

Sampling and analysis

Analytical monitoring:
not specified
Details on sampling:
No data

Test solutions

Vehicle:
no
Details on test solutions:
No data

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Strain: own laboratory breed
- Age at study initiation: > 3h; < 24h
- Method of breeding: Adult animals were cultivated in the test facility in glass vessels (volume: 4 litres). The medium was changed once a week and the animals were fed twice daily with algae (Scenedesmus supspicatus).

No more data available

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
24 h
Post exposure observation period:
No data

Test conditions

Hardness:
No data
Test temperature:
21°C
pH:
No data reported
Dissolved oxygen:
No data reported
Salinity:
No data
Nominal and measured concentrations:
Nominal concentrations: 8.31; 83.1; 103.9; 166.3; 415.7; 831.4 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 100 ml glass vessels, test volume 100 ml per vessel
- No. of organisms per vessel: 10 animals
- No. of vessels per concentration (replicates): two
- No. of vessels per control (replicates): two controls without test substance and two reference controls with potassium dichromate (concentration: 2.0 mg/L)


TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: Synthetic water according to DIN 38 412 Part 11


STOCK SOLUTION OF THE TEST SUBSTANCE
- Preparation: a saturated solution was prepared under hydrolytic conditions. A suspension of the substance in de-ionized water was adjusted to a pH of 12 with NaOH, stirred over 72 h at 25°C and filtrated through a folded paper filter.
- Analysis: 304 mg dissolved organic carbon /L
- Concentration of the stock solution: 831.4 mg/L, calculated from the DOC of the solution and the carbon content in the substance of 36.57% C


OTHER TEST CONDITIONS
- Photoperiod: study performed in a dark chamber


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mobility was determined after 24 hours


No more data available
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EC10
Effect conc.:
111.9 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% confidence interval: 41.5 - 130.9 mg/L
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
209.9 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% confidence interval: 188.4 - 417.4 mg/L
Details on results:
cf table 1 in remarks on results
No further data
Results with reference substance (positive control):
The reference substance potassium dichromate should have an EC50 after 24h between 0.6 mg/L and 2.1 mg/L according to OECD guideline 202. The immobilization rate after 24 hours with 2 mg/L of potassium dichromate was 70% and is thus in agreement with the scheduled value. But the lower limit for the EC50 of potassium dichromate could not be verified because only one concentration was tested.
Reported statistics and error estimates:
Using the measured data, a logaritmic regression was executed and based on these results the EC-values were calculated.

Results of the logaritmic regression analysis:
- slope: coefficient=64%; 95% confidence limits: lower = 17%, upper = 110%; standard errors: +/- 10.75%
- intersection of the y-axis: coefficient=-290%; 95% confidence limits: lower = -525%, upper = -55%; standard errors: +/- 54,71%
- correlation coefficient: 0,973

Any other information on results incl. tables

- Table 1: Immobilization rates of Daphnia magna exposed to a hydrolyzed solution of p-chlorobenzotrichloride and the controls over a period of 24 hours

Dilution of the stock solution (mg/L) Replicate # of immobilized daphnids
24h
% of immobilized daphnids
24h
Mean (%)
24h
Blank control 1 0 0 5
2 1 10
8.31 1 0 0 0
2 0 0
83.1 1 0 0 0
2 0 0
103.9 1 1 10 5
2 0 0
166.3 1 1 10 20
2 3 30
415.7 1 10 100 100
2 10 100
831.4 1 10 100 100
2 10 100
Reference control with potassium dichromate
2 1 4 40 70
2 10 100

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
partially
Conclusions:
This study assessed the acute toxicity of p-chlorobenzotrichloride to Daphnia magna Straus (Crustacea) in a static system according to DIN 38 412 Part 11, which is similar to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Under the test conditions, an EC50 (24h) was reported of 209.9 mg/L with a 95% confidence interval ranging from 188.4 to 417.4 mg/L. However, the EC50 value reported in this study after a 24h exposure cannot be used directly to assess the effect on the environment. Therefore, p-chlorobenzotrichloride can not be classified as hazardous to the aquatic environment.
Executive summary:

The authors in this study assessed the acute toxicity of p-chlorobenzotrichloride (CAS n° 5216 -25 -1) to Daphnia magna Straus (Crustacea) in a static system. The test was performed according to DIN 38 412 Part 11, which is similar to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). The test organisms were exposed for 24h to six different concentrations of p-chlorobenzotrichloride (i.e. 8.31; 83.1; 103.9; 166.3; 415.7; 831.4 mg/L) and a negative as well as a reference control (i.e. potassium dichromate; 2.0 mg/l) was included. For each condition, two replicates, each containing 10 dapnids between 3 and 24h, old were used.

Under the test conditions an EC50 (24h) was reported of 209.9 mg/L with a 95% confidence interval ranging from 188.4 to 417.4 mg/L and the negative and reference control gave the expected results.

Although the statistical analysis used results in a EC50-value with a large 95% confidence interval, it is likely that performing the test according to the OECD guideline 202 (meaning 48h of exposure and analysis with appropriate statistical methods such as probit analysis) would also give a EC50-value above 1 mg/L but less than this observed value. This would mean that the test substance could then be considered as non-hazardous to the aquatic environment. However, the EC50 value reported in this study after a 24h exposure cannot be used directly to assess the effect on the environment. Hence, p-chlorobenzotrichloride can not be classified as hazardous to tjhe aquatic environment according to the CLP regulation n° 1272/2008 EC.

No data on the GLP procedure was reported but validity criteria were partially fulfilled. The validity criteria concerning the percentage of immobilized daphnids in the blank control was met since an immobilization below 10%, namely 5%, was reported. The second and last validity criteria dealing with dissolved oxygen concentration at the end of the test, could not be assessed. Although the standard procedure followed includes measurements of the dissolved oxygen concentrations, these results were not reported.

As this study is sufficiently described and performed according to national standard methods, it should be considered as reliable with restrictions, a Klimisch 2 study, a test procedure in accrodance with national standards with acceptable restirctions.