Ethanol

Biodegradation in water and sediment: simulation tests

Administrative data

Endpoint:

biodegradation in water: sediment simulation testing

Type of information:

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

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Acceptable study, meets basic scientific principles Hypothesis and analogue approach for read-across: This substance (S-Ethanol, composition 2) has degree of ethanol purity between 76 - 82%. Methanol is the main impurity of the target substance (conc. 13-14 %), and considered the major driver for adverse effects based on its properties and relative quantity in the substance. Therefore, testing of the substance itself was considered unnecessary. Instead the available REACH registration data of ethanol and methanol is used in order to update the chemical safety assessment of this substance. Other impurities of this substance are taken into account for self-classification, but there is no need to consider their properties in hazard assessment because of low concentrations (see IUCLID section 1.2; composition 2).

Data source

Reference

Reference Type:

publication

Title:

Methane production and simultaneous sulphate reduction in anoxic, salt marsh sediments

Author:

Oremland, R.S. et al.

Year:

1982

Bibliographic source:

Nature 296: 143-145

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Degradation test with methanol in anaerobic sediments from a salt marsh

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Methanol

EC Number:

200-659-6

EC Name:

Methanol

Cas Number:

67-56-1

Molecular formula:

CH4O

IUPAC Name:

methanol

Details on test material:

- Name of test material (as cited in study report): Methanol
- Analytical purity: no data

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
no data

Radiolabelling:

yes

Study design

Oxygen conditions:

anaerobic

Inoculum or test system:

natural water / sediment

Details on source and properties of surface water:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): San Francisco Bay Water
- salinity: ca. 2%
- sulphate: ca. 18mM

Details on source and properties of sediment:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): upper 15 cm of a salt marsh, San Francisco Bay at Palo Alto, California, USA
- sediment: black, highly reduced, containing methane (ca. 8 mL/L wet sediment), strong smell of hydrogen sulphide. Sediment also contained abundant plant material (such as roots, rhizomes, stems and leaves) of Spartina foliosa
- Storage length: < 1h
- sampling: glass jars were filled completely with sediment to exclude air, sealed and transported back to the laboratory

Details on inoculum:

- Preparation of inoculum for exposure: Sediments were homogenized anaerobically with San Francisco Bay water. Homogenate was dispensed into Erlenmeyer flasks and sealed. The homogenate was further diluted with bay water to yield a slurry

Duration of test (contact time):

5 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

310 other: µmol / 110 mL in flask

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

340 other: µmol / 110 mL in flask

Based on:

test mat.

Initial test substance concentration 3

Initial conc.:

500 other: µmol / 110 mL in flask

Based on:

test mat.

Parameter followed for biodegradation estimation:

other: conversion of methanol to methane

Details on study design:

TEST CONDITIONS
- Test temperature: 19°C
- Continuous darkness: yes

TEST SYSTEM
- Method used to create anaerobic conditions: acc. to Oremland (1981)
- Number of culture flasks/concentration: 8 (4 with and without BES)

Reference substance

Reference substance:

not specified

Results and discussion

Test performance:

no details available

% Degradation

% Degr.:

83 - 91

Parameter:

other: conversion to methane

Sampling time:

3 d

Transformation products:

yes

Identity of transformation products

Identity of transformation products 1

No.:

#1

Reference

Reference substance name:

Unnamed

IUPAC name:

methane

Inventory number:

InventoryMultipleMappingImpl [inventoryEntryValue=EC 200-812-7]

CAS number:

74-82-8

Identity of transformation products 2

No.:

#2

Reference

Reference substance name:

Unnamed

IUPAC name:

dioxomethane

Inventory number:

InventoryMultipleMappingImpl [inventoryEntryValue=EC 204-696-9]

CAS number:

124-38-9

Identity of transformation products 3

No.:

#3

Reference

Reference substance name:

Unnamed

IUPAC name:

Oxidane

Inventory number:

InventoryMultipleMappingImpl [inventoryEntryValue=EC 231-791-2]

CAS number:

7732-18-5

Identity:

Water

Identifier:

IUPAC name

Identity:

Water

Identifier:

IUPAC name

Identity:

water

Identifier:

other: InChl

Identity:

InChI=1/H2O/h1H2

Molecular formula:

H2O

Molecular weight:

18.015

SMILES notation:

O

InChl:

InChI=1S/H2O/h1H2

Details on transformation products:

no further details

Evaporation of parent compound:

not specified

Volatile metabolites:

not specified

Residues:

not specified

Details on results:

no further details

Results with reference substance:

no data

Any other information on results incl. tables

In the experiments with dilute slurries, methanol-amended flasks produced methane and production levelled off after 5 days incubation. After 3 days incubation, 83-91% conversion of the methanol had occurred.

Methanol stimulates methanogenesis but not sulphur reduction.