Hydrocarbons, C11-C12, isoalkanes, <2% aromatics

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Type of information:

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

Adequacy of study:

key study

Study period:

March to April 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This robust summary has a reliability rating of 1 because the study followed a standard guideline, followed GLP guidelines, and was conducted without deviations that would invalidate the study.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 306 (Biodegradability in Seawater)

Deviations:

no

GLP compliance:

yes

Radiolabelling:

no

Oxygen conditions:

aerobic

Inoculum or test system:

other: Natural seawater

Details on source and properties of surface water:

Seawater was collected from the Burnham-on-Crouch estuary at high tide. The estuary has no industrial input.

Details on inoculum:

Indigenous microorganisms contined in natural seawater.

Duration of test (contact time):

28 d

Initial conc.:

1.21 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

A surfactant (Nonidet P40) was used to emulsify the test substance. Background BOD for the surfactant was determined by evaluating the BOD of the surfactant alone in parallel test systems.

Reference substance:

acetic acid, sodium salt

% Degr.:

0

Parameter:

O2 consumption

Sampling time:

7 d

% Degr.:

5

Parameter:

O2 consumption

Sampling time:

14 d

% Degr.:

4

Parameter:

O2 consumption

Sampling time:

21 d

Key result

% Degr.:

11

Parameter:

O2 consumption

Sampling time:

28 d

Transformation products:

not measured

Evaporation of parent compound:

not measured

Volatile metabolites:

not measured

Residues:

not measured

Validity criteria fulfilled:

yes

Conclusions:

The test substance biodegraded to an extent of 11% after 28 days.

Executive summary:

The test substance biodegraded to an extent of 11% after 28 days.

Reference 2

Endpoint:

biodegradation in water: sediment simulation testing

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is readily biodegradable

Transformation products:

not measured

Description of key information

There is no data available for this substance. However, key data is available for a structural analogue, Hyd C12-C14, isoalkanes, <2% arom, and presented in the dossier. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Biodegradation in seawater:

One study on Hyd C12-C14, isoalkanes, <2% arom conducted according to OECD 306 guideline was available and it concluded to the ready biodegradability of the substance in seawater according to OECD criteria for biodegradability in seawater. Hyd C12-C14, isoalkanes, <2% arom biodegraded to an extent of 11% after 28 days in seawater. the substance was therefore concluded to be not inherently biodegradable.

Biodegradation in sediment:

This substance is considered readily biodegradable. Therefore, in accordance with REACH Annex IX column 2 exemption, the simulation testing in sediment does not need to be conducted