REAKTIV-ORANGE DYPR 1410

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:

12 October 1998 to 14 October 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

Principles of method if other than guideline:

Methodology of Commission Directive 88/302/EEC, Official Journal of the EC L 133 , Part C: Biodegrad ability: Test for inhibition of oxygen consumption (corresponds for the most part to the test method OECD 209).

GLP compliance:

yes

Analytical monitoring:

not required

Details on sampling:

Test concentrations (mg/l): 100, 1000, 10 000
Type of application: direct weighing

Vehicle:

no

Details on test solutions:

The study is carried out with nominal weights.

Test organisms (species):

activated sludge

Details on inoculum:

Test organism
Type: activated sludge (mixed population of different microorganisms)
Origin: aeration tank of a waste water plant treating predominantly domestic sewage (Wupper area water authority)
Pre-treatment: none
pH of the suspension before application: 7.0

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Post exposure observation period:

No post exposure observation period

Hardness:

No data

Test temperature:

20.2-20.4

pH:

7.9-8.1

Dissolved oxygen:

5.9-6.2-start of study

Salinity:

Not applicable.

Nominal and measured concentrations:

Test concentrations (mg/l): 100, 1000, 10 000

Details on test conditions:

Test concentrations (mg/l):100, 1000, 10 000
** Test substance concentration in physico-chemical oxygen consumption control (mg/I): 10 000
Type of application: direct weighing
Test concentration of the activated sludge: 320 mg/l
Test temperature: 20 ±2⁰C
Incubation time: 3 hours with permanent aeration

Reference substance (positive control):

yes

Remarks:

3.5-dichlorophenol

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 10 000 mg/L

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

Test concentrations are given as nominal concentrations and have not been confirmed by analytical methods.

The physico chemical oxygen consumption is determined at 10 000 mg/l test substance. No physico chemical oxygen consumption has been determined. Therefore lower concentrations of the test substance cause no physico chemical oxygen consumption (deduced values).

Results with reference substance (positive control):

Details under any other information. The reference substance performed as expected.

Reported statistics and error estimates:

No data

Measured values of test substance / control/ reference substance

	Test concentration [mg/l]	Initial concentration [mg/250ml]	O2-start   [mg O2/l]	O2-end   [mg O2/l]	Time  [min.]	Temp.   [C⁰]	pH
Test substance	100	25	6.3	3.0	6	20.4	8.1
	1000	250	6.4	2.5	7	20.3	8.1
	10 000	2500	6.2	3.0	6	20.4	7.9
Control 1			5.9	2.6	6	20.2	8.1
Control 2			6.5	2.8	7	20.2	8.1
Physio-chemical oxygen consumption control	10 000	2 500	8.9	8.9	9	20.5	7.4
Reference substance	5	2.5	6.2	2.8	7	20.0	8.0
	10	5	7.0	5.0	7	20.1	7.9
	20	10	8.7	7.6	9	20.3	8.3

 

STUDY EVALUATION-Test substance: Reaktiv-orange DYPR 1410

Test concentration     [mg/l]	Respiratory rate test substance   [mg/l . h]	Phys. chem. O2-consumption   [mg/l . h]	Respiratory rate-phys. chem. O2-consumption [mg/l . h]	Inhibition
100	33.0	0.0	33.0	0.0
1000	33.4	0.0	33.4	0.0
10 000	32.0	0.0	32.0	1.2
Control, mean	32.4
Control 1	33.0
Control 2	31.7

 

STUDY EVALUATION-Reference substance: 3.5-Dichlorophenol

Test concentration [mg/l]	Respiratory rate [mg/l . h]	Inhibition [%]
5	29.1	10.2
10	17.1	47.2
20	7.3	77.5

 

Validity criteria fulfilled:

yes

Conclusions:

Toxicity of Reaktiv-Orange DYPR 1410 to activated sludge:EC 50 > 10000 mg/1

Executive summary:

Study conducted to Commission Directive 88/302/EEC, Official Journal of the EC L 133 , Part C: Biodegradability: Test for inhibition of oxygen consumption (corresponds for the most part to the test method OECD 209). Performed in compliance with the Principles of Good Laboratory Practice (GLP).

 

A defined quantity of activated sludge is mixed with synthetic medium and the respiratory rate is measured. This rate is compared to those measured in test preparations with various con­centrations of the test substance. In order to check the sensitivity of the activated sludge used, 3.5-dichlorophenol is used as a reference substance.

 

Toxicity of Reaktiv-Orange DYPR 1410 to activated sludge:EC 50 > 10000 mg/l.

The substance is not harmful to sewage sludge organisms.

Description of key information

Toxicity of Reaktiv-Orange DYPR 1410 to activated sludge:EC 50 > 10000 mg/L. The substance is not harmful to sewage sludge organisms.

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

10 000 mg/L

Additional information

Study conducted to Commission Directive 88/302/EEC, Official Journal of the EC L 133 , Part C: Biodegradability: Test for inhibition of oxygen consumption (corresponds for the most part to the test method OECD 209). Performed in compliance with the Principles of Good Laboratory Practice (GLP).

 

Toxicity of Reaktiv-Orange DYPR 1410 to activated sludge:EC 50 > 10000 mg/L. The substance is not harmful to sewage sludge organisms.