N4,N4'-hexane-1,6-diylbis[N-butyl-6-chloro-N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)-1,3,5-triazine-2,4-diamine]

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test (Carbon and Ammonium Oxidation))

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material:
190701
- Expiration date of the lot/batch:
24 July 2021
- Purity:
>90%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
Room Temperature
- Stability under storage conditions:
Stable

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Preparation of the Medium (synthetic sewage feed) Constituents Supplier Conc.(g/L)
Peptone MERCK 16.00
Meat extract MERCK 11.00
Urea SIGMA 3.00
Sodium chloride SIGMA 0.70
Calcium chloride dihydrate SIGMA 0.40
Magnesium sulphate heptahydrate SIGMA 0.20
Anhydrous potassium monohydrogen phosphate SIGMA 2.80
Deionised water MILLIPORE To 1000 mL

Test organisms (species):

activated sludge

Details on inoculum:

the preparation of the inoculum a sample of aerobic mud was selected by the mixed treatment plant of urban (about 66%) and industrial (about 34%) liquid sewage situated in San Rocco near Monza (MB). The plant of treatment is managed by “BRIANZACQUE SRL (Monza- Italia)”.
Activated sludge was collected and used on day of collection.
No coarse particles were present so settling was not necessary. Then the mud samples, before their use, were washed and analyzed to prepare the inoculum. The sludge was continuously aerated at the test temperature.
The suspended solids in the mud solution was 3 g/L to havein the final mixture a concentration of 1.5g/L.

Test type:

static

Water media type:

other: deionized water

Limit test:

no

Total exposure duration:

3 h

Test temperature:

20 ± 2℃

pH:

7.37-7.46

Nominal and measured concentrations:

Due to the low solubility in water of the test item the solution were prepared directly in the bottles to facilitate the solubility in water of the soluble components of the test item. Test were performed at 3 different nominal concentrations of the test item (1000 mg/L, 100 mg/L and 10 mg/L).

Details on test conditions:

TEST SYSTEM
- Test vessel: bottles
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3
- No. of vessels per abiotic control (replicates): 3
- Sludge concentration (weight of dry solids per volume): The suspendedsolids in the mud solution was 3 g/L to havein the final mixture a concentration of 1.5 g/L.


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: All dilutions were done using deionized water.

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Details on results:

The obtained results, in compliance with assay validity criteria, interpreted in accordance to OECD 209: 2010, show that the ECsvalue of the test item “N4,N4’-HEXANE-1,6-DIYLBIS[N-BUTYL-6-CHLORON, N°-BIS(2,2,6,6-TETRAMETHYLPIPERIDIN-4-YL)- 1,3,5-TRIAZINE-2,4-DIAMINE]” after 3 hours results greater than 1000 mg/L.

Mean percent inhibition total respiration rate of the test item “N4,N4’-HEXANE-1,6-DIYLBIS[N-BUTYL-6-CHLORO-N,N’-BIS(2,2,6,6-TETRAMETHYLPIPERIDIN-4-YL)- 1,3,5-TRIAZINE-2,4-DIAMINE]” is detailed in the following table:
Concentration %of inhibition total respiration rate Test item 10 mg/L 7.84
10 mg/L 7.84
100 mg/L 9.23
1000 mg/L 12.69

Results with reference substance (positive control):

Mean percent inhibition total respiration rate of the reference substance is detailed in the following table:
Concentration % of inhibition total respiration rate Reference substance “3,5 - Dichlorophenol”
1 mg/l 15.11
10 mg/L 61.82
50 mg/L 84.66
EC50 of 3,5-Dichlorophenol: 6.479 mg/Lfor total respiration

Validity criteria fulfilled:

yes

Executive summary:

The respiration rates of activated sludge both in control, reference and treatment groups have been measured in an enclosed cell containing an oxygen electrode after a contact time of 3 hours at 20°C+2 ℃.

The obtained results, in compliance with assay validity criteria, interpreted in accordance to OECD 209: 2010, show that the EC50 value of the test item “N4,N4’-HEXANE-1,6-DIYLBIS[N-BUTYL-6-CHLORON,N’-BIS(2,2,6,6-TETRAMETHYLPIPERIDIN-4-YL)- 1,3,5-TRIAZINE-2,4-DIAMINE]” after 3 hours results greater than 1000 mg/L.

Description of key information

The obtained results, in compliance with assayvalidity criteria, interpreted in accordance to OECD 209: 2010, show that the EC50 value of the test item “N4,N4’-HEXANE-1,6-DIYLBIS[N-BUTYL-6-CHLORON,N’-BIS(2,2,6,6-TETRAMETHYLPIPERIDIN-4-YL)- 1,3,5-TRIAZINE-2,4-DIAMINE]” after 3 hours results greater than 1000 mg/L.

Key value for chemical safety assessment

EC50 for microorganisms:

1 000 mg/L