(E)-3-methyl-5-cyclopentadecen-1-one

Toxicity to soil microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil microorganisms

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2002-06-02 to 2002-08-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Experiment conducted under GLP, and following OECD Guidelines. No deviations were observed.

Qualifier:

according to guideline

Guideline:

OECD Guideline 216 (Soil Microorganisms: Nitrogen Transformation Test)

Deviations:

no

Principles of method if other than guideline:

not applicable.

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 28 February 2000. Signed on 26 April 2000

Analytical monitoring:

no

Details on sampling:

- Concentrations: 1000 mg/Kg
- Sampling method: Based on the results of the range-finding test, a limit test was conducted at a concentration of 1000 mg/Kg to confirm that at the maximum recommended concentration given in the test guidelines no effect on nitrogen transformation was observed.
- Sample storage conditions before analysis: none.

Vehicle:

yes

Details on preparation and application of test substrate:

VEHICLE:
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone
- Concentration of vehicle in test medium (stock solution and final test solution): no data
- Evaporation of vehicle before use: no data

Test organisms (inoculum):

soil

Total exposure duration:

28 d

Remarks:

none

Test temperature:

21 +/-1°C

Moisture:

40%

Details on test conditions:

TEST SYSTEM
- Testing facility: glass beakers
- Test container (type, material, size): no data
- Amount of soil: 50 g
- No. of replicates per concentration: 6
- No. of replicates per control: 3
- No. of replicates per vehicle control: 3

SOIL INCUBATION
- Method: series of individual subsamples

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Geographical reference of sampling site (latitude, longitude): Heath farm, Leicester Lane, Warwickshire, UK
- History of site: The sampling site had not been treated with crop protection products for approximately 3 years and no organic fertiliser had been applied for approximately 5 years prior to sampling.
- Vegetation cover: no data
- Treatments with pesticides or fertilizers: no
- Accidental contamination: no data
- Other: none
- Depth of sampling: no data
- Initial microbial biomass as % of total organic C: 282 µg C/g equivalent to 2.0% of the total soil organic carbon content.

VEHICLE CONTROL PERFORMED: yes

RANGE-FINDING STUDY
- Test concentrations: 1.0, 10, 100, 1000 mg/kg
- Results used to determine the conditions for the definitive study: no effect observed.

Nominal and measured concentrations:

1000 mg/Kg

Reference substance (positive control):

no

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

>= 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

nitrate formation rate

Details on results:

See table 6.3.4/1 in "Any other information on results incl. tables".

Results with reference substance (positive control):

Not applicable.

Reported statistics and error estimates:

no data

Table 6.3.4/1: Nitrate concentrations on each sampling occasion.

Nominal concentration (mg/Kg)		Nitrate concentration (mg NO3/Kg)
		Day
		0	6	28
Control	R1	123.38	212.28	367.59
	R2	121.20	201.76	362.87
	R3	124.83	197.76	359.97
Solvent control	R1	118.66	214.09	332.03
	R2	133.90	216.63	331.66
	R3	132.08	216.27	339.65
1000	R1	140.43	199.58	341.10
	R2	141.52	201.76	344.36
	R3	142.97	205.38	355.61
	R4	143.70	203.21	344.73
	R5	139.34	206.47	378.11
	R6	140.43	204.66	379.92

Validity criteria fulfilled:

yes

Conclusions:

The test material showed no significant effect on the nitrogen transformation activity of soil microorganisms at a test concentration of 1000 mg/Kg over a 28 -day period and therefore can be considered to have no long-term effect on nitrogen transformation in soil.
NOEC >= 1000 mg/Kg.

Executive summary:

A study was performed to assess the long-term effect of the test material after a single exposure, on nitrogen transformation activity of soil microorganisms. The method followed that described in the OECD guidelines 216, EPPO 1994, under GLP.

Following a preliminary range-finding test (conducted over a range of test concentrations of 1.0, 10, 100, and 1000 mg/Kg) soil microorganisms were exposed to the test material at a single concentration of 1000 mg/Kg for 28 days at a temperature of 21 +/-1°C with the addition of powdered Lucerne-green-grass meal to act as a respiratory substrate. The inhibition effect of the test material on nitrogen transformation was assessed by the determination of nitrate concentration on the soil samples and compared to data obtained from control and solvent control soil samples.

The test material showed no significant effect on the nitrogen transformation activity of soil microorganisms at a test concentration of 1000 mg/Kg over a 28 -day period and therefore can be considered to have no long-term effect on nitrogen transformation in soil.

NOEC >= 1000 mg/Kg.

Description of key information

OECD Guideline 216, EPPO 1994, GLP, key study, validity 1:

No significant effect on the nitrogen transformation activity of soil microorganisms at a test concentration of 1000 mg/Kg over a 28 -day period.

No long-term effect on nitrogen transformation in soil.

NOEC >= 1000 mg/Kg.

Key value for chemical safety assessment

Long-term EC10 or NOEC for soil microorganisms:

1 000 mg/kg soil dw

Additional information

One key study is available to assess the long-term effect of the registered substance after a single exposure, on nitrogen transformation activity of soil microorganisms. The method followed that described in the OECD guidelines 216, EPPO 1994, under GLP.

Following a preliminary range-finding test (conducted over a range of test concentrations of 1.0, 10, 100, and 1000 mg/Kg) soil microorganisms were exposed to the test material at a single concentration of 1000 mg/Kg for 28 days at a temperature of 21 +/-1°C with the addition of powdered Lucerne-green-grass meal to act as a respiratory substrate. The inhibition effect of the test material on nitrogen transformation was assessed by the determination of nitrate concentration on the soil samples and compared to data obtained from control and solvent control soil samples.

The test material showed no significant effect on the nitrogen transformation activity of soil microorganisms at a test concentration of 1000 mg/Kg over a 28-day period and therefore can be considered to have no significant effect on long-term nitrogen transformation in soil up to the maximum concentration tested.

NOEC >= 1000 mg/Kg.