1,3-dichlorobenzene

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

1996 -01-30 till 1996-02-20

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

OECD guideline study performed under GLP. This study has however significant weaknesses and was therefore not used for the assessment for the following reasons: 1. Now clear data for LOEC and NOEC are presented 2. Concentration- effect-relation: No clear correlation can be stated in the region of 0.1, 0.32, 0.56 and 1. 0 mg/L. The number of offspring varies in the region of 40 to 50 per adult, independantly from the concentration. The number of offspring at 0.56 mg/L was even higher than at 0.1 and 0.32 mg/L. 3. A modifyer was used although the substance has a good water solubility (>100 mg/L) and there is no reason to use the modifyer in the concentration region of 0.1 to 1.8 mg/L. Furthermore, the concentration of the modifyer is not described in the report and thus it is not clear whether the limit concentration of 0.1 mg/L as given by the guideline was exceeded. 4. Two other reliable studies are available with a clear concentration-effect-correlation which show quite similar results.

Data source

Reference

Reference Type:

review article or handbook

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

OECD chemicals test guideline No. 202 "daphnids, acute immobilization test were performed in accordance with the pre-breeding test (1984).

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,3-dichlorobenzene

EC Number:

208-792-1

EC Name:

1,3-dichlorobenzene

Cas Number:

541-73-1

Molecular formula:

C6H4Cl2

IUPAC Name:

1,3-dichlorobenzene

Test material form:

other: liquid

Details on test material:

- Purity: 100.0 %
- Empirical formula: C6H4Cl2
- Molecular mass: 147.00 g/mole

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0.10, 0.32, 0.56, 1.0 and 1.8 mg/L plus control
- Sample storage conditions before analysis: 1,3-dichlorobenzene was stored in our reagent shelf

Test solutions

Vehicle:

yes

Details on test solutions:

The required amount of 1,3-dichlorobenzene was diluted with hydrogenated castor oil as a solubilizing agent (HCO-40): ethanol = 3: 2 (these two solutions were thoroughly mixed 5 times) and fill up with dilution water to 100 mL volume (stock solution).

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

- Name: Daphnia magna
- Experimental design: 40 animals/concentration
- Temperature: 20 ± 1 °C
- Photoperiod: 16 h light / 8 h dark
- Feed: Chlorella vulgaris
0.1 ~ 0.2 mg C per Daphnia (organic carbon content) / day.

It was using a juvenile of Daphnia magna within 24 hours of birth to the test.
This species, those that were obtained from the National Institute for Environmental Studies, has been bred in Tama Institute.

Daphnia magna less than 24 hours old at the beginning of the test, laboratory bred, apparently healthy and with a known history (breeding method, pretreatment) are used in this test.
In addition, container Daphnia of abnormalities are observed, many container mortality individual, is dormant eggs and male Daphnia of the resulting container was not used.

Study design

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

21 d

Test conditions

Hardness:

4 °dH (71.8 mg CaCO3/L)

Test temperature:

19.7 ~ 20.8 °C measured at each test vessel at the beginning and the end of the test

pH:

7.6 ~ 8.6 measured at each test vessel at the beginning and the end of the test

Dissolved oxygen:

5.6 ~ 9.4 mg O2/L measured at each test vessel at the beginning and the end of the test

Nominal and measured concentrations:

Concentrations: 0.10, 0.32, 0.56, 1.0 and 1.8 mg/L (nominal) plus control
0 day: Concentrations of 0.08, 0.28, 0.45, 0.8 and 1.6 mg/L (measured) = 80 ~ 89 %
14 days: Concentrations of 0.09, 0.30, 0.51, 1.0 and 1.7 mg/L (measured) = 90 ~ 100 %

Details on test conditions:

- Test volume: 1150 mL
- Test type: semi-static, change of the test volume, every 2 days
- Stations: 4 per concentration
- Animals: 40 Daphinds per concentration
- Temperature: 20 ± 1 ℃
- Photoperiod: 16 hours light / 8 hours dark

Reference substance (positive control):

yes

Remarks:

(potassium dichromate, reagent grade, Wako Pure Chemicals Industry)

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

1 - 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Duration:

21 d

Dose descriptor:

other: ErC50

Effect conc.:

< 0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

immobilisation

Effect concentrations 3

Duration:

21 d

Dose descriptor:

other: NOECr

Effect conc.:

< 0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 4

Duration:

21 d

Dose descriptor:

other: LOECr

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Results with reference substance (positive control):

48 hours EC50 value of inhibition test was 0.72 mg/L

Any other information on results incl. tables

Mortality (%) of parental Daphnia

Concentration	Days
(mg/L)	1, 2	4	7	14	21
control	0.0	0.0	0.0	0.0	2.5
solution control	0.0	0.0	0.0	2.5	5.0
0.10	0.0	0.0	0.0	2.5	5.0
0.32	0.0	0.0	0.0	2.5	2.5
0.56	0.0	0.0	0.0	0.0	0.0
1.0	0.0	0.0	0.0	2.5	10.0
1.8	0.0	25.0	30.0	52.5	60.0

Mean cumulative numbers of juveniles produced per adult (ΣF1/P)

Conc.	Days
(mg/L)	0, 2, 4, 6	8	10	12	14	16	18	20	21
cont.	0	4.08	15.90	27.30	38.70	53.20	69.12	80.67	94.58
sol. cont.	0	4.40	15.20	28.63	43.57	56.62	73.57	89.29	100.41
0.10	0	4.83	16.06	23.82	29.11	29.56	39.78	40.01	40.01
0.32	0	4.58	14.91	24.44	33.99	35.52	45.03	45.19	45.19
0.56	0	5.70	17.48	24.55	35.25	38.38	50.48	50.65	50.68
1.0	0	1.70	5.88	11.43	14.71	19.69	26.80	31.60	39.10
1.8	0	0.00	0.23	1.02	2.06	3.29	4.87	7.71	9.89

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

(- The inmobilisation and other abnormalities in the controls did not exceed 10 % by the end of the test. - The dissolved oxygen concentration remained above 3 mg/L throughout the exposure period.)

Conclusions:

The chronic toxicity to aquatic invertebrates (Daphnia magna) was determined to five concentrations under semi-static conditions for a period of 21 days.
After 21 days of exposure a LC50 of 1.0 ~ 1.8 mg/L and an EC50 of < 0.10 mg/L were measued; a NOECr of < 0.10 mg/L and a LOECr of 0.10 mg/L were calculated.

Executive summary:

The chronic toxicity to aquatic invertebrates (Daphnia magna) was determined according to the OECD guideline no. 202 "Daphnia acute immobilisation test, preliminary breeding examination" (1984), prolonged at 21 days. Five concentrations (0.10, 0.32, 0.56, 1.0 and 1.8 mg/L) and blank control solution was exposed under semi-static conditions for a period of 21 days.

The meaured concentrations confirmed that deviation from the nominal concentrations was less than 20 % (measured concentrations were in the range of 80 ~ 100 % of nominal concentrations). The mortality of the parents was 2.5 % in the concentrations 0.10 ~ 1.0 mg/L at 14 - 21 days. In the concentration of 1.8 mg/L was the mortality of the parents 60 % at 21 days.

After 21 days of exposure a LC50 of 1.0 ~ 1.8 mg/L and an EC50 of < 0.10 mg/L were measued; a NOECr of < 0.10 mg/L and a LOECr of 0.10 mg/L were calculated.