(R*,S*)-(±)-α-[1-(methylamino)ethyl]benzyl alcohol hydrochloride

Toxicity to microorganisms

Administrative data

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:

other: Guideline study in compliance with GLP-criteria.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(R*,S*)-(±)-α-[1-(methylamino)ethyl]benzyl alcohol hydrochloride

EC Number:

205-153-9

EC Name:

(R*,S*)-(±)-α-[1-(methylamino)ethyl]benzyl alcohol hydrochloride

Cas Number:

134-71-4

Molecular formula:

C10 H15 N O .Cl H

IUPAC Name:

(1-hydroxy-1-phenylpropan-2-yl)(methyl)azanium chloride

Details on test material:

- Name of test material (as cited in study report): DL-Ephedrin-Hydrochlorid
- Physical state: solid, crystalline, white
- Homogeneity: homogeneous
- Stability under test conditions: stable
- STorage conditions: ambient (RT)

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION:
A stock solution of 2000 mg/L was prepared. The test concentrations were made by diluting the stock solution with deionized water.

Test organisms

Test organisms (species):

activated sludge

Details on inoculum:

Activated sludge from laboratory wastewater plant treating municipal sewage. The inoculum was washed, brought to a concentration of 5 g/L dry substance and aerated during the night. 50 mL were added to a total volume of 250 mL to obtain a concentration of 1 g/L dry substance in the test.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

30 min

Test conditions

Test temperature:

20 ±2 °C

pH:

5.1 -7.6

Dissolved oxygen:

- Oxygen concentration during aeration: > 2.5 mg/L
- Oxygen concentration immediately before measurement: > 6.5 mg/L

Nominal and measured concentrations:

- Nominal concentrations: 0 (control), 248, 496, 1000 mg/L.

Details on test conditions:

TEST SYSTEM:
- Test vessels: Erlenmeyer-vessel (nominal volume 250 mL)
- Test volume: 250 mL
- Synthetic medium: 8 mL/vessel, 100-fold concentrated OECD medium

TEST MEDIUM / WATER PARAMETERS
- Culture medium different from test medium: yes
- Test medium: 8 ml/vessel 100-fold concentrated OECD medium

Reference substance (positive control):

yes

Remarks:

3,5 dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

30 min

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Effect concentrations 2

Duration:

30 min

Dose descriptor:

other: EC20

Effect conc.:

ca. 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Effect concentrations 3

Duration:

30 min

Dose descriptor:

EC10

Effect conc.:

ca. 380 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

No EC10 value was reported. It was determined visually by the reviewer from the graphical presentation of data.

With an EC20 value of >100 mg/L, disturbances in the biodegradation process of activated sludge are not to be expected if the test substance is correctly introduced into wastewater treatment plants at low concentrations.

Results with reference substance (positive control):

EC20: ca. 1.5 mg/L
EC50: ca. 8.3 mg/L