Copper, [[[[3-[(5-chloro-2,6-difluoro-4-pyrimidinyl)amino]phenyl]amino]sulfonyl]-29H,31H-phthalocyaninato(2-)-N29,N30,N31,N32]-, aminosulfonyl sulfo derivs., sodium salts

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From September 24th to October 02nd, 1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Version / remarks:

4 April 1984

GLP compliance:

yes

Details on test solutions:

The test solutions were prepared by adding the test material directly to the test water.

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Source: ARA Rhein, Pratteln, Switzerland.
- Treatment: the sludge is centrifuged and washed three times with drinking water, then suspended in water with a solids content of 4 g/l and after the
addition of 20 ml synthetic sewage per litre sludge suspension aerated overnight at 20 °C.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test temperature:

20 ± 2 °C

Nominal and measured concentrations:

18, 32, 56, 100, 180, 560, 1000 and 1800 mg/l, nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: 1000 ml glass beaker with 500 ml test solution.
- Aeration: air flow 0.5 to 1 l/min.
- No. of vessels per control: 2 replicates (one at the beginning and one at the end of the test).
- Sludge concentration: 1.6 g/l

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: drinking water with a total hardness of about 180 mg CaCO3/l and pH 7.6 to 8.0.

MEASURING APPARATUS
500 ml flat bottomed flask, totally filled with test solution.

EFFECT PARAMETERS MEASURED
The percentage inhibition of the respiration was plotted against concentration on logarithmic probability paper. The EC50, EC20 and EC80 were calculated with normal statistical procedures (Regression line).

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

3 854.7 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Details on results:

EC20 (3h): 122.8 mg/l

Results with reference substance (positive control):

EC50 (3h): 5 - 5.8 mg/l

Rate of respiration inhibition

Concentration (mg/l)	Inhibition (%)	Mean value from
18	11.7	1 test
32	15.1	1 test
56	10.3	1 test
100	21.9	2 tests
180	14.1	1 test
560	34.4	2 tests
1000	39.9	3 tests
1800	45.1	2 tests

The oxygen rates of the controls in the four test serie were between 0.74 and 1.5 mg O₂/l/min.

Calculation of the regression line

Y (inhibition %)	Probits	X (conc in mg/l)	log X
11.7	3.8099	18	1.2552
15.1	3.9678	32	1.5051
10.3	3.7354	56	1.7482
21.9	4.2244	100	2
14.1	3.9242	180	2.2552
34.4	4.5984	560	2.7482
39.9	4.7233	1000	3
45.1	4.8769	1800	3.2552

Conclusions:

EC50 (3h): 3854.7 mg/l (graphically determined, based on nominal conc).

Executive summary:

The bacterial toxicity potential of the substance was investigated in respiration inhibition test. The test was conducted in accordance with the OECD Guideline for Testing of Chemicals, No. 209 (Activated Sludge, Respination Inhibition Test). Activated sludge of a predominantly domestic sewage were used. The percentage inhibition of the respiration was plotted against concentration on logarithmic probability paper. The EC50, EC20 and EC80 were calculated with normal statistical procedures (Regression line).

After the exposure period of 3 hours, the EC20 was estimated to be 122.8 mg/l, while the EC50 was estimated to be 3854.7 mg/l.

Conclusion

EC50 (3h): 3854.7 mg/l (graphically determined, based on nominal conc).

Description of key information

EC50 (3h): 3854.7 mg/l (graphically determined, based on nominal conc).

Key value for chemical safety assessment

EC50 for microorganisms:

3 854.7 mg/L

Additional information

The bacterial toxicity potential of the substance was investigated in respiration inhibition test, in accordance with the OECD Guideline 209. Activated sludge of a predominantly domestic sewage were used. The percentage inhibition of the respiration was plotted against concentration on logarithmic probability paper. The EC50, EC20 and EC80 were calculated with normal statistical procedures (Regression line).

After the exposure period of 3 hours, the EC20 was estimated to be 122.8 mg/l, while the EC50 was estimated to be 3854.7 mg/l.