(Z)-1,3-dichloropropene

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18th October 1988 - 2nd March 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted in accordance with generally accepted scientific principles, possibly with incomplete reporting or methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)

Deviations:

yes

Remarks:

As the test substance is volatile, it was injected into the oxygen uptake measuring apparatus during sludge addition. The contact time between the test substance and activated sludge was therefore reduced from three hours to 10 minutes

Principles of method if other than guideline:

Part C: Methods for the Determination of Ecotoxicity, Official Journal of the European Communities No. L 133 31, 118-122 (1988).

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(Z)-1,3-dichloropropene

EC Number:

233-195-8

EC Name:

(Z)-1,3-dichloropropene

Cas Number:

10061-01-5

Molecular formula:

C3H4Cl2

IUPAC Name:

1,3-dichloroprop-1-ene

Details on test material:

NAME: CIS-l,3-DICHLOROPROPENE
BATCH (& OTHER) NUMBERS SNC NO: 1986; 88009
TOXICOLOGY REF. NUMBER: ST88/253
SOURCE: Shell Nederland Raffinaderij B.V., Rotterdam
DATE RECEIVED: 18th October 1988
APPEARANCE: Clear colourless liquid
CHARACTERIZATION: Actual Analysis
Cis-l,3-DCP (SMS 2060) 94.51% and 95.45%
(LPM 3998) 96.9 %
(LPM 4922) 97.51%
Trans-1,3-Dichloropropene (LPM 3998) 1. 5 %
Cis+Trans (LPM 3998) 98.4%
3,3-DCP (LPM 3988) 0%
Benzene 0%
1,2-Dichloropropane 0.25%
2,3-Dichloropropane 0.01%
Water % m/m (LPM 4687) 0.03%
Edenol D81 (LPM 4389) 1.0%
Origin of sample CAS-CMDU-S
DENSITY: 1.224 g/ml at 15.2 ºC
(Measured at SRC using Paar DMA 35 density meter)
DATE RELEASED: 18th November 1988 and 30th May 1989

Storage of this test substance
Following its arrival in Compound Control this test substance was stored in the dark at ambient temperature under nitrogen.

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

NDA

Test solutions

Vehicle:

no

Details on test solutions:

32 mg/l, 100 mg/l, 320 mg/l and 1 000 mg/l solutions

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

Samples of activated sludge from Canterbury Sewage Works were aerated for three hours at 20 °C in the presence of a standard amount of synthetic sewage feed.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

N/A

Test conditions

Hardness:

NDA

Test temperature:

20 ºC

pH:

NDA

Dissolved oxygen:

NDA

Salinity:

NDA

Nominal and measured concentrations:

Nominal: 32, 100, 320 and 1000 mg/l

Details on test conditions:

Flasks amended with a range of concentrations of a reference inhibitor (3,5-dichlorophenol), and flasks containing sludge plus feed but no inhibitory substances ("controls") were run in parallel. After a contact time of three hours, the oxygen consumption (respiration) rate of each reference inhibitor and control sample was measured. As cis-1,3-dichloropropene is volatile, aeration for three hours would have resulted in substantial losses of the test substance. The compound was therefore injected into the measuring vessel during the addition of sludge plus feed (previously incubated for three hours). The contact time between the activated sludge and the test substance was therefore the duration of the respiration rate measurement (7-10 minutes) and not three hours.

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Duration:

10 min

Dose descriptor:

EC50

Effect conc.:

279 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

The effect of cis-l,3-dichloropropene on the respiration rate of activated sludge is given in Table 1.

Results with reference substance (positive control):

As the EC50 for the reference inhibitor 3,5-dichlorophenol was within the range 5-30 mg/l (8.5 mg/l), and the relative standard deviation of the two controls was <15%, the test was considered to be valid.

Reported statistics and error estimates:

The respiration rate of the activated sludge is calculated from the linear portion of the oxygen consumption curve and is given in units of mg O2/g sludge/h. Percentage inhibition of respiration rate is calculated at each concentration of test or reference substance using the equation:

% Inhibition = (1 - 2Rs / (Rc1 + Rc2)) x 100

where Rs = respiration rate at tested concentration of test or reference substance,

RCI - respiration rate of control "C1",
RC2 - respiration rate of control "C2".

If a suitable range of inhibition was observed over the range of test or reference substance concentrations, then inhibition curves of % inhibition at each concentration against log10 concentration will be plotted. The concentration of substance which inhibits respiration by 50 % (EC50) can then be interpolated from this curve.

Any other information on results incl. tables

Table 1: Effect of cis-l,3-dichloropropene on the respiration rate of activated sludge

Substance	Concentration (mg/L)	% Inhibition
Cis-1,3-Dichloropropene       EC50	32	37
	100	37
	320	56
	1000	58
	279
3,S-dichlorophenol         EC50	1	-12
	3.2	18
	10	58
	32	83
	100	91
	8.5

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The effect of cis-1,3-dichloropropene on the respiration rate of activated sludge has been assessed by a modified version of the EEC procedure. As the test substance is volatile, it was injected into the oxygen uptake measuring apparatus during sludge addition. The contact time between the test substance and activated sludge was therefore reduced from three hours to the duration of the respiration.rate measurement (approximately 10 minutes).

The EC50 for cis-l,3-dichloropropene under these conditions was found to be 279 mg/l.

Executive summary:

The aim of this study was to determine the effect of cis-l ,3-dichloropropene on the respiration rate of activated sludge. As the test substance is volatile, it was injected into the oxygen uptake measuring apparatus during sludge addition. The contact time between the test substance and activated sludge was therefore reduced from three hours to the duration of the respiration rate measurement (approximately 10 minutes).

The EC50 for cis-l ,3-dichloropropene under these conditions was found to be 279 mg/l.