C14-16 (even numbered) and C16 (branched) saturated and unsaturated aliphatic hydrocarbons

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non GLP, guideline study minor restrictions in design and/or reporting but otherwise considered adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD 301D

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

C14-16 (even numbered) and C16 (branched) saturated and unsaturated aliphatic hydrocarbons

EC Number:

700-762-0

Molecular formula:

All molecules present in the mixture have the general molecular formula CnH2n for olefins or CnH2n+2 for the paraffin’s with n being an even number

IUPAC Name:

C14-16 (even numbered) and C16 (branched) saturated and unsaturated aliphatic hydrocarbons

Test material form:

liquid: viscous

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

Sampled on days 5,15, and 28

Test solutions

Vehicle:

yes

Details on test solutions:

Test substance added to test medium from stock solution containing 2.4 g/l olefins PQ11 emulsified in Dobane P/T sulphonate. Final test concentration was 2 mg/l olefins 103 PQ 11

Test organisms

Test organisms (species):

activated sludge

Details on inoculum:

micro organisms obtained from Sittingbourne Sewage Works

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

28 d

Post exposure observation period:

none

Test conditions

Hardness:

data not reported

Test temperature:

21 + 1 degrees C

pH:

data not reported

Dissolved oxygen:

measured as endpoint

Salinity:

not applicable

Nominal and measured concentrations:

Final test concentration was 2 mg/l olefins 103 PQ 11.

Details on test conditions:

Controls with no microbial inoculum (control) and with medium plus microbial inoculum only (blank) were included. Bottles incubated at 21 + 1 degrees C and the extent of biodegradation determined by measuring the oxygen concentration in the bottles at 5,15 and 28 days.

Reference substance (positive control):

yes

Remarks:

sodium benzoate

Results and discussion

Effect concentrations

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: inhibition of biodegradation of reference substance

Details on results:

64% ThOD had occured by day 5 in the test bottles with both test substance and reference substance present.

Results with reference substance (positive control):

validity criteria met

Reported statistics and error estimates:

data not reported

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

No inhibition of microbial activity under test conditions. More than 25% ThOD was observed within 14 days indicating that the test substance did not inhibit the degradation of sodium benzoate.

Executive summary:

This study was conducted to standard guidelines. The validity criteria of the test guideline were met. The inhibitory effect of olefins C10 -14 was investigated as part of the ready biodegradability screening test, and microbial respiration was not found to be significantly inhibited at the concentration tested.