(2R)-4-hydroxybutan-2-aminium (2S)-hydroxy(phenyl)acetate

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

26-05-2002 to 27-05-2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study (OECD), validity criteria fulfilled

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

L-2-hydroxy-2-phenylacetic acid

EC Number:

210-276-6

EC Name:

L-2-hydroxy-2-phenylacetic acid

Cas Number:

611-71-2

IUPAC Name:

hydroxy(phenyl)acetic acid

Details on test material:

ChiPros (R)-Mandelsäure: (R)-mandelic acid (purity: 100 %; impurities: 0.1 % mandelic acid amide)

Sampling and analysis

Analytical monitoring:

no

Test organisms

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- preparation of inoculum: washed, conc. of dry matter: 5 g/l, aerated during the night

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

30 min

Test conditions

Dissolved oxygen:

- oxygen concentration during aeration: > 2.5 mg/l
- oxygen concentration immediatley before measurement: > 6.5 mg/l
- duration of measurement of oxygen consumption: 8-10 min

Details on test conditions:

- test vessel: Erlenmeyer flask (250 ml)
- test volume: 250 ml

- test assays: blank control (3x), reference substance (3x) and test substance (1000 mg/l)
- synthetic medium: 8 ml (100-fold concentrated OECD medium)
- inoculum: 50 ml (final conc. of dry matter: 1 g/l)
- dilution water: deionised water

Results and discussion

Effect concentrations

Duration:

30 min

Dose descriptor:

other: EC20

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

- reference substance: 3,5-dichlorophenol; EC50 is in the range of 5-30 mg/l

Any other information on results incl. tables

effect value (30 min, mg/l)
EC20:  > 1000 mg/l

parameter            BC (average)   TS      RS1   RS2   RS3
oxygen concentration (mg/l)
   start             6.8-7.8        6.9     6.9   8.1   8.6
   6 min             5.0-6.5        5.0     5.0   7.1   8.3

oxygen consumption rate
(mg O2/l/h)          18             19      19    10     3

specific oxygen consumption rate
(mg O2/l/h)          18             19      19    10     3

change in oxygen consumption rate compared to BC
(%)                   -             -6      -6    44    83

pH
before addition of inoculum (corrected)
                     7.1             7.6    7.2   7.3  7.0
after test end (30 min)
                     -               7.8    -     -    -
BC = blank control
RS = reference substance (reference substance conc.: RS1: 1 mg/l; RS2: 10  mg/l; RS3: 100 mg/l)
TS = test substance

effect values for reference substance (30 min, mg/l):
EC20   ca.  3.3
EC50   ca. 15
EC80   ca. 85