6,6-dimethoxy-2,5,5-trimethylhex-2-ene

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: Inhibition control in Ready Biodegradability test performed according to OECD 301F

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

- Name of test material (as cited in study report): METHYL PAMPLEMOUSSE
- Substance type: colourless to pale yellow liquid
- Physical state: liquid
- Lot/batch No.: 9000469522
- Expiration date of the lot/batch: May 12, 2004

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Fresh activated sludge from a biological waste water treatment plant treating predominantly domestic sewage in the city of Geneva
- Storage conditions/Preparation of inoculum for exposure: washed tree times in the mineral medium and kept aerobic being used in the same day
- Concentration of sludge: 3.970 g/L (dry weight of suspended solids); to obtain a concentration of 30 mg/L (dry weight) in a 250 mL flask, 1.89 mL of sludge is needed (inoculum).

Reference substance (positive control):

yes

Duration:

35 d

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Comparison of respiration of flasks containing test chemical + positive control and flasks containing positive control only

Details on results:

The curves obtained with the reference substance alone and with Methyl Pamplemousse + reference substance show no toxic effect of Methyl Pamplemousse to the micro-organisms at the test concentration (100 mg/l) (see illustration section).

Conclusions:

The toxicity of Methyl Pamplemousse to microorganisms was assessed in an inhibition control of a standardised ready test performed according to OECD 301F. Methyl Pamplemousse did not inhibit the degradation of the positive control, reference substance, at a test concentration of 100mg/L. This concentration can be considered the NOEC for the toxicity to STP microorganisms.

Description of key information

In a standardised ready biodegradability screening study (Givaudan 2003), no toxicity was observed in an inhibition control at a test concentration of 100 mg/L. This concentration can be considered as a NOEC for the toxicity to STP microorganisms.

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

100 mg/L