Sodium naphthalene-1-sulphonate

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge nitrification inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data is from authoritative database

Justification for type of information:

Data is from authoritative database

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

To evaluate Toxicity of test material Sodium 1-Naphthalenesulfonate on microorganism

GLP compliance:

not specified

Specific details on test material used for the study:

IUPAC: Sodium 1-Naphthalenesulfonate
Mol. formula: C10H7NaO3S
Molecular Weight:230.218
InChI:1S/C10H8O3S.Na/c11-14(12,13)10-7-3-5-8-4-1-2-6-9(8)10;/h1-7H,(H,11,12,13);/q;+1/p-1
Smiles:c12c(S(=O)(=O)[O-])cccc1cccc2.[Na+]

Details on test solutions:

water solution of test material and AS mixed before experiment and aerated for 10 min

Test organisms (species):

activated sludge

Details on inoculum:

Source: pilot activated sludge plant at Water Research Center, Swindon, UK

Test type:

static

Water media type:

freshwater

Limit test:

no

pH:

7.0 - 8.0

Nominal and measured concentrations:

50 - 200 mg/l

Details on test conditions:

-in vitro; samples of actively-nitrifying sludge mixed liquor, suspended solids, SS in concentration 2000 mg/l; standard procedure for assessment of nitrification inhibition, respiration rate of AS determined from the rate of O2 depletion measured by oxygen electrode

Reference substance (positive control):

not specified

Dose descriptor:

IC50

Effect conc.:

926 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of nitrification rate

Remarks on result:

other: slightly inhibited nitrification

Dose descriptor:

other: IC20

Effect conc.:

195 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of nitrification rate

Remarks on result:

other: no other details available

Validity criteria fulfilled:

not specified

Conclusions:

The inhibition concentration (IC50) for the nitrifying bacteria was observed to be 926 mg/l

Executive summary:

Toxicity of microorganism was evaluated for the test material Sodium 1-Naphthalenesulfonate . Water solution of test material and AS mixed before experiment and aerated for 10 min. Activated sludge having nitrifying bacteria were used obtained from a pilot activated sludge plant at Water Research Center, Swindon. In vitro; samples of actively-nitrifying sludge mixed liquor, suspended solids, SS in concentration 2000 mg/l; standard procedure for assessment of nitrification inhibition,  respiration rate of AS determined from the rate of O2 depletion measured by oxygen electrode. The nominal concentrations tested were 50 - 200 mg/l. The inhibition concentration (IC50) for the nitrifying bacteria was observed to be 926 mg/l , the (IC20) was observed to be 195 mg/l. Slightly inhibited nitrification was observed.

Description of key information

Toxicity to microorganism:

Toxicity of microorganism was evaluated for the test material Sodium 1-Naphthalenesulfonate . Water solution of test material and AS mixed before experiment and aerated for 10 min. Activated sludge having nitrifying bacteria were used obtained from a pilot activated sludge plant at Water Research Center, Swindon. In vitro; samples of actively-nitrifying sludge mixed liquor, suspended solids, SS in concentration 2000 mg/l; standard procedure for assessment of nitrification inhibition,  respiration rate of AS determined from the rate of O2 depletion measured by oxygen electrode. The nominal concentrations tested were 50 - 200 mg/l. The inhibition concentration (IC50) for the nitrifying bacteria was observed to be 926 mg/l , the (IC20) was observed to be 195 mg/l. Slightly inhibited nitrification was observed.

Key value for chemical safety assessment

EC50 for microorganisms:

926 mg/L

Additional information

Toxicity to microorganism:

Toxicity of microorganism was evaluated for the test material Sodium 1-Naphthalenesulfonate . Water solution of test material and AS mixed before experiment and aerated for 10 min. Activated sludge having nitrifying bacteria were used obtained from a pilot activated sludge plant at Water Research Center, Swindon. In vitro; samples of actively-nitrifying sludge mixed liquor, suspended solids, SS in concentration 2000 mg/l; standard procedure for assessment of nitrification inhibition,  respiration rate of AS determined from the rate of O2 depletion measured by oxygen electrode. The nominal concentrations tested were 50 - 200 mg/l. The inhibition concentration (IC50) for the nitrifying bacteria was observed to be 926 mg/l , the (IC20) was observed to be 195 mg/l. Slightly inhibited nitrification was observed.