Ethyldimethyl[2-[(2-methyl-1-oxoallyl)oxy]ethyl]ammonium ethyl sulphate

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22/08/1991-25/08/1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented report of a guideline study conducted to GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

Deviations:

yes

Remarks:

The growth characteristics of the bacteria were not measured by turbidimetr by using a microbiological method with Petri dish cultures according to Bringmann and Kühn, 1977.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material: Adame-Quat
- Physical state: liquid
- CAS number: 44992-01-0
- Manufacturing code: B4846
- Composition of test material, percentage of components: 80 % aqueous solution
- Lot/batch No.: 40034237
- pH-value: 6.56
- Storage condition of test material: at 4°C in the dark

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

yes

Details on test solutions:

Demineralised water

Test organisms

Test organisms (species):

Pseudomonas putida

Details on inoculum:

- Laboratory culture: master cultures DSM N° 50026 supplied from "Deutsche Sammlung für Mikroorganismen, Göttinger, FRG
- Method of cultivation: Columbia agar (Api Bio Merieux, No 43041)
- Preparation of inoculum for exposure: Master cultures were incubated 1 day at 30°C 1 day at approximately 30°C and then stored in refrigerator at 4°C
- Initial biomass concentration: For the test the preliminary culture was diluted with sterile sodium chloride solution (0.9 %) to an extinction of 0.1 (at 436 nm) to gain the bacteria suspension.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Post exposure observation period:

After one day of incubation, the growth of bacteria colonies on the petri dishes was evaluated macroscopically.

Test conditions

Hardness:

No data

Test temperature:

30°C

pH:

6.56

Dissolved oxygen:

No data

Salinity:

No data

Nominal and measured concentrations:

The nominal concentrations tested were 3, 6, 12, 24, 49, 98, 195, 391, 781, 1563, 3125, 6250, 12500, 25000, 50000, 100000, 200000, 400000 mg/L.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, fill volume: 8.5cm Petri dishes
EFFECT PARAMETERS MEASURED: growth of bacteria colonies on the Petri dishes was evaluated macroscopically
TEST CONCENTRATIONS
- Spacing factor for test concentrations: dilution factor: 2
STATISTICS
The EC50-value was calculated as follows: The two concentrations which showed semi-maximal growth were added and then divided by two. The minimal inhibition concentration was calculated as the mean value between the concentration where no growth was observed and the concentration where minimal growth was observed.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

195 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Effect concentrations 2

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

586 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Effect concentrations 3

Duration:

24 h

Dose descriptor:

IC100

Effect conc.:

2 344 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Any other information on results incl. tables

The growth of the bacterial colonies on the Petri Dishes was evaluated macroscopically. The results are given in the following table:

		Growth at dilution of 10^-2
Concentration mg/l	Dilution factor	Incubation A	Incubation B
control	control	+++	+++
400,000	1:2	–	–
200,000	1:4	–	–
100,000	1:8	–	–
50,000	1:16	–	–
25,000	1:32	–	–
12,500	1:64	–	–
6,250	1:128	–	–
3,125	1:256	–	–
1,563	1:512	+	+
781	1:1024	++	++
391	1:2048	++	++
195	1:4096	+++	+++
98	1:8192	+++	+++
49	1:16392	+++	+++
24	1:32784	+++	+++
12	1:65568	+++	+++
6	1:131136	+++	+++
3	1:262772	+++	+++

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The results of this study indicate that the test substance Adame-Quat completely reduces bacteria growth at concentrations between 3125 and 400000 mg/L. No effect in comparison to the control was seen at a concentration of 195 mg/L which is considered to be the NOEC. The EC50 is 586 mg per litre and the MIC (EC100) is 2344 mg/L. Based on the results obtained in this test system, the test substance is considered to be slightly toxic to bacteria.