2-chlorobuta-1,3-diene

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988-03-07 to 1988-03-28

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This report is based on a study report "Daphnia magna, Reproduction test with chloroprene", the corresponding raw data and additional information from the executing laboratory "Institut fur Umweltanalyse". Recent regulatory requirements necessitate this re-evaluation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD 202 (Daphnia sp., Acute Immobilisation Test and Reprduction Test

Deviations:

no

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Chloroprene

IUPAC Name:

Chloroprene

Constituent 2

Reference substance name:

2-chlorobuta-1,3-diene

EC Number:

204-818-0

EC Name:

2-chlorobuta-1,3-diene

Cas Number:

126-99-8

Molecular formula:

C4H5Cl

IUPAC Name:

2-chlorobuta-1,3-diene

Details on test material:

Purity: 99.3%
Molecular weight: 88.54 g/mol

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Sampling and analysis

Details on sampling:

Not applicable

Test solutions

Vehicle:

no

Details on test solutions:

A stock solution was prepared to give the desired series of test concentrations. To achieve this 500 mg of the test item were added to 1 litre of water. Mortality, pH-value and O2 concentration were checked at the start and after each water change.
The test vessels were glass beakers covered with watch glasses.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna STRAUS, parthenogenetic females, strain of Bundesgesundheitsamt Berlin (clone breed).
Maintenance and Acclimatisation: A population of parthenogenetic females of syncronised age and structure were maintained under constant temperature conditions (20 +/- 1°C) at a 16:8 hour light-dark photoperiod. The daphnia were exclusively fed with unicellular green algae (Desmodesmus subspicatus) "ad libitum".
Mortalities of parent Daphnia during the culture period were recorded daily in a semi-quantitative way. The neonates were separated from their parent Daphnia by filtration prior to the acute test.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Post exposure observation period:

Not applicable

Test conditions

Hardness:

Not reported

Test temperature:

20°C

pH:

Range during the study - 8.0 - 8.3

Dissolved oxygen:

Range during the study - 8.0 - 9.3 mg/L

Salinity:

Not applicable

Nominal and measured concentrations:

Control, 1.0, 3.2, 10.0, 31.6 and 100 mg/L

Details on test conditions:

Light intensity: ca. 800 lux.
Feeding of the Daphnica with living cells of Desmodesmus subspicatus was done daily.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Details on results:

The following results were obtained at the end of the 21 day exposure period of the Daphnia reproduction test.
Reproduction rate:
R 21 (control): 100%
R 21 (1.0 mg/L): 74.1%
R 21 (3.2 mg/L): 97.5%
R 21 (10.0 mg/L): 87.2%
R 21 (31.6 mg/L): 67.0%
R 21 (100 mg/L): 54.7%

Results with reference substance (positive control):

Not applicable

Any other information on results incl. tables

Mean reproduction rate

Test item concentration (mg/L)	Mean reproduction rate
Control	39.3 (n = 10)
1.0	29.1 (n = 10)
3.2	38.3 (n = 10)
10.0	34.1 (n = 9)
31.6	26.3 (n = 10)
100.0	21.5 (n = 10)

 

Immobilisation/mortality rate and mean reproduction rate of parent Daphnia

Test item concentration (mg/L)	Immobilisation/mortality rate of parent Daphnia		Mean reproduction rate of parent Daphnia
	absolute	%	absolute	%
Control	-	0	39.3 (n = 10)	100
1.0	-	0	29.1 (n = 10)	74.1
3.2	-	0	38.3 (n = 10)	97.5
10.0	1	10	34.1 (n = 9)	87.2
31.6	-	0	26.3 (n = 10)	67.0
100.0	-	0	21.5 (n = 10)	54.7

 

Applicant's summary and conclusion

Conclusions:

Young female Daphnia were exposed to the test item added to water at a range of concentrations (1.0, 3.2, 10.0, 31.6, 100.0 mg/L) for a period of 21 days. Defined concentrations of the test item led to a certain percentage reduction of the parthenogenetic reproducton rate at the end if the 21 day study period. The living offspring was counted daily along with the renewal of the test medium.

A SIDS Initial Assesment Report for 8th SIAM reviewed this report and concluded that "based on the concentration-response relationship and considering the biological variability, the NOEC for reproduction rate is 3.2 mg/L."

Executive summary:

Young female Daphnia were exposed to the test item added to water at a range of concentrations (1.0, 3.2, 10.0, 31.6, 100.0 mg/L) for a period of 21 days. Defined concentrations of the test item led to a certain percentage reduction of the parthenogenetic reproduction rate at the end if the 21 day study period. The living offspring was counted daily along with ther enewal of the test medium. The following reproduction rates were obtained at the end of the 21 day exposure period of the Daphnia reproduction test: R 21 (control) 100%; R 21 (1.0 mg/L) 74.1%; R 21 (3.2 mg/L) 97.5%; R 21 (10.0 mg/L) 87.2%; R 21 (31.6 mg/L) 67.0% and R 21 (100 mg/L) 54.7%. The no-observed effect concentration based on reproduction was <1. 0 mg/L.