Toluene-2-sulphonamide

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The concentration of the test substance in the test solution was measured at the beginning and the end of exposure. No further details.

Vehicle:

not specified

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: algae
- Strain: ATCC 22662

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

23 ± 2ºC

Nominal and measured concentrations:

- Nominal: 0 (control); 3.2, 10, 32, 100 and 320 mg/L
- Measured (0 h): 0, 2.4, 7.4, 27, 78 and 260 mg 1 L

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: Shake culture (100 rpm), 100 mL (OECD medium)
- Initial cells density: 1×10^4cells/mL
- No. of vessels per concentration (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: continuous lighting
- Light intensity and quality: 4000 to 5000 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : growth inhibition, area under the curve

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

170 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

7.4 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

57 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

other: AUC

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

7.4 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

other: AUC

Details on results:

- Growth rate values: calculated from original data because 0-72 hr toxicity value of Alga growth rate was not reported on the report before 2003.

Validity criteria fulfilled:

not specified

Conclusions:

Based on the growth rate, the 72h-EC50 of the test item in algae is 170 mg/L and the 72h-NOEC is 7.4 mg/L.

Executive summary:

An algae growth inhibition test was conducted with the test item in Pseudokirchneriella subcapitata / Selenastratum capricornutum (ATCC 22662), according to the OECD guideline 201, under GLP conditions. Algae were exposed to the test item at concentrations of 0 (control), 3.2, 10, 32, 100 and 320 mg/L for 72 hours at 23 ± 2ºC. The test item concentration was measured by GC-MS at the beginning and at the end of the exposure time and, since the measured concentrations were outside the range ± 20 % of the nominal, all results were given as measured values. Based on the growth rate, the 72h-EC50 of the test item in algae was determined to be 170 mg/L and the 72h-NOEC was 7.4 mg/L (average value of the measured concentration).

Description of key information

Key study. Method according to the OECD guideline 201, GLP study. Based on the growth rate, the 72h-EC50 of the test item in algae was determined to be 170 mg/L and the NOEC was 7.4 mg/L (average value of the measured concentration).

Key value for chemical safety assessment

EC50 for freshwater algae:

170 mg/L

EC10 or NOEC for freshwater algae:

7.4 mg/L