Pyridinium, 3-[(diethylamino)carbonyl]-1-(3-sulfopropyl)-, inner salt

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18.08.2014 to 17.09.2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

(1992)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Version / remarks:

(2008)

GLP compliance:

yes (incl. QA statement)

Remarks:

LAUS GmbH, Auf der Schafweide 20, D-67489 Kirrweiler (Germany)

Test material

Test material information

Constituent 1

Reference substance name:

3-(diethylcarbamoyl)-1-(3-sulfonatopropyl)pyridin-1-ium

EC Number:

807-112-6

Cas Number:

1393708-17-2

Molecular formula:

C13H20N2O4S

IUPAC Name:

3-(diethylcarbamoyl)-1-(3-sulfonatopropyl)pyridin-1-ium

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Pyridiniumsulfonate
- Physical state: solid (powder)
- Analytical purity: 99.8% (HPLC)
- Impurities (identity and concentrations): N,N-Diethyl-nicotinamid <0.02%
- Purity test date: 2014-02-19
- Lot/batch No.: CHZT000001
- Expiration date of the lot/batch: 2016-02
- Storage condition of test material: room temperature (-5 - + 40°C), in a closed container and dry in the dark

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Activated sludge from a biologic sewage treatment plant (NW-Lachen-Speyerdorf, Germany) was used as inoculum. The sewage treatment plant is treating mostly domestic sewage
- Laboratory culture: no
- Preparation of inoculum for exposure: The sludge was filtered, washed with tap water twice, then washed with and re-suspended in test medium. The activated sludge was then aerated until use.
- Pretreatment: no
- Concentration of sludge:25 mg dry matter/L
- Initial cell/biomass concentration: 4220 mg suspended solids/L
- Water filtered: no

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

38 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: according to guideline
- Additional substrate: no
- Solubilising agent (type and concentration if used): no
- Test temperature: 21.6-23.5°C
- pH: at test start not reported; pH at the end of the test and before addition of HCl: 7.5 in the test vessel with test item
- pH adjusted: no
- Aeration of dilution water: The culture flasks were filled with medium and inoculum and aerated for 72 h with purified, CO2-free, moistened air to purge the system of CO2
- Suspended solids concentration: 25 mg dry matter/L
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: culture flasks
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: The culture flasks were filled with medium and inoculum and aerated for 72 h with purified, CO2-free, moistened air to purge the system of CO2
- Measuring equipment: Carbon Analyser TOC multi N/C 2100S, Analytik Jena
- Test performed in closed vessels: yes
- Details of trap for CO2: The emitted CO2 was trapped in 0.25 m NaOH. Two scrubber flasks containing 100 mL each were connected in series to the test vessels. The initial inorganic carbon value of the 0.25 m NaOH was separately determined in each flask

SAMPLING
- Sampling frequency: sampling was performed on days 0, 2, 4, 7, 9, 11, 14, 18, 23 and 29. On day 28, 5 mL HCl were added to each test flask to drive off dissolved CO2.
- Sampling method: During the test, 10 samples (1 mL each) from each front scrubber flask were taken to determine CO2 evolution.
- Sample storage before analysis: no

CONTROL AND BLANK SYSTEM
- Inoculum blank: performed
- Abiotic sterile control: performed
- Toxicity control: performed
- Other: aniline was used as readily biodegradable positive control

Reference substance

Reference substance:

aniline

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

1

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

The reference substance aniline reached the pass level of >60% degradation within 7 d.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

Pyridiniumsulfonate proved to be not readily biodegradable (1% biodegradation after 28 d) in a study conducted according to OECD Guideline 301 B and EU Method C.4-C.

Executive summary:

The ready biodegradation of the pyridiniumsulfonate was investigated in a study conducted according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test; 1992) and EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test; 2008) over a period of 28 days and using non-adapted activated sludge as inoculum. The biodegradation rate was determined by measurement of CO2 evolution. Inoculum blank, procedural/functional control with reference substance aniline, and toxicity control using 39.5 mg/L test item and 25.2 mg/L reference compound (ca. 20 mg organic carbon/L each) were performed.

This study is regarded as reliable without restriction and satisfies the guideline requirements for ready biodegradation.

The test item proved to be not readily biodegradable under the test conditions employed (1% biodegradation after 28 d). The functional control reached the pass level > 60% after 14 d. In the toxicity control containing both test and reference item 30.6% biodegradation occurred within 14 d thus indicating that the test item was not inhibitory at the concentration tested.