Chloro(1-methylethyl)magnesium

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-01-24 to 2013-01-24

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Version / remarks:

, adopted 4 April 1984

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: "The Guidelines for the Testing of Chemicals" State Environmental Protection Administration (SEPA) of China, 2004, No.209, 'Activated Sludge, Respiration Inhibition Test'

Deviations:

no

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Chloro(1-methylethyl)magnesium

EC Number:

213-947-1

EC Name:

Chloro(1-methylethyl)magnesium

Cas Number:

1068-55-9

Molecular formula:

C3H7ClMg

IUPAC Name:

chloro(1-methylethyl)magnesium

Constituent 2

Reference substance name:

Isopropylmagnesium chloride

IUPAC Name:

Isopropylmagnesium chloride

Test material form:

other: liquid: 20% in Tetrahydrofuran

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

16 mL of synthetic sewage feed and specific weight of test item were made up to 300 mL with Tap water (aerating for 24 hours). 200 mL of microbial inoculation liquid was added and the total mixture (500 mL) poured in to the vessel

Test organisms

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- 4 g/L activated sludge (pH = 7.49) was prepared as microbial inocluation liquid when it was used
- activated sludge streamd from Guizhou estate water Co., LTD

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test conditions

Test temperature:

Temperature range 19.5 °C - 19.7°C

pH:

pH range 7.59 - 7.72

Dissolved oxygen:

Dissolved oxygen range 3.28 - 6.50

Nominal and measured concentrations:

Nominal concentrations:
25,0 mg/L, 50.0 mg/L, 100 mg/L, 200 mg/L, 400 mg/L

Details on test conditions:

Observed testconcentrations were made up in 15-min intervalls to give a series of vessels containing different concnetrations of test substance. The contact time in vessels was three hours. Subsequently the respiration rate of 10 minutes was meassured in each vessel.

- Temperature 19.2 °C
- Relative humidity 43%

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorphenol

Results and discussion

Effect concentrations

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 400 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):

LC50 (3h) = 10.6 mg/L
This is in accordance with the accepted 5 - 30 mg/L range, which satisfied the test requirement. The results of reference substance are valid.

Reported statistics and error estimates:

The respiration rate was calculated from the recorder trace as mg O2/L. In order to calculate the inhibitory effet of a test substance the repration rate was expressed as a percentage of the mean of the two control respiration rates.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the performed Activated Sludge Respiration Inhibition Test, the EC50 value of test item was determined as higher than 400 mg/L.

Executive summary:

The acitvated sludge respiration inhibition test of isopropyl magnesium chloride was conducted. Therefore test item was given to activated sludge for 3 hours. Subsequently the respiration rate of 10 minutes was measured. The respiration rate was calculated from the recorder trace as mg O2/L. In order to calculate the inhibitory effet of a test substance the respiration rate was expressed as a percentage of the mean of the two control respiration rates. Corresponding to the observed concentrations (25, 50, 100, 200 and 400 mg/L isopropyl magnesium chloride) the respiration depression were 5.0%, 12.6%, 15.4%, 19.5% and 24.2%. The result showed that EC50 was greater than 400 mg/L. 3,5 -Dichlorphenol was used as positive control. The calculated EC50 (3 hours) = 10.6 mg/L and was in the accepted range from 5 to 30 mg/L.