Reaction mass of 1,3-dioxane-5,5-dimethanol and 1,3-Propanediol, 2-(hydroxymethyl)-2-[(methoxymethoxy)methyl]-

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 May - June 12 2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Remarks:

Study performed to OECD guideline, however no statement of GLP compliance has been made and study report lacks certain important details, such as information concerning the test material.

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test)

Deviations:

no

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Activated sludge taken from Klagshamn waste water plant, Sweden.
- Laboratory culture: Not reported.
- Method of cultivation: Not reported.
- Storage conditions: Not reported.
- Storage length: Not reported.
- Preparation of inoculum for exposure: Not reported.
- Pretreatment: Not reported.
- Concentration of sludge: The activated sludge contained 5.9g suspended solids/L.
- Initial cell/biomass concentration: Not reported.
- Water filtered: Not reported.
- Type and size of filter used, if any: Not reported.

Duration of test (contact time):

42 d

Initial conc.:

80 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

DOC removal

Parameter followed for biodegradation estimation:

TOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium: Refer to table below.
- Additional substrate: N/A
- Solubilizing agent (type and concentration if used): Not used.
- Test temperature: 20 - 25ºC
- pH: 7.4
- pH adjusted: yes
- CEC (meq/100 g): Not reported
- Aeration of dilution water: Media were bubbled with air for the duration of the test.
- Suspended solids concentration: Not reported.
- Continuous darkness: no - flasks incubated in a room with diffused light.


TEST SYSTEM
- Culturing apparatus: Not specified
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: Air was bubbled using an air pump through a long glass tube which ended at the bottom of the flask.
- Method used to create anaerobic conditions: Not applicable.
- Measuring equipment: Not specified.
- Test performed in closed vessels due to significant volatility of test substance: Not specified.
- Test performed in open system: Not specified.
- Details of trap for CO2 and volatile organics if used: Not reported.


SAMPLING
- Sampling frequency: TOC (total organic carbon) concentration was measured in each flask on days 0 and 28. DOC (dissolved organic carbon) concentration was measured for each period (0, 7, 14, 21, and 28 days) in each inoculated flask. The DOC concentration in the flask with sterile medium was measured only on day 0 and 28.
- Sampling method: Not specified.
- Sterility check if applicable: A flask containing sterile medium was analyzed for TOC and DOC concentration on days 0 and 28.
- Sample storage before analysis: Not specified.


CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes
- Abiotic sterile control: Yes
- Toxicity control: Not specified


STATISTICAL METHODS: Not reported.

Reference substance:

acetic acid, sodium salt

Preliminary study:

N/A

Test performance:

According to SS-EN ISO 7827:1996/OECD 301A the test is valid if the degradation of the reference compound after 14 days is more than 70%. In this case the degradation in more then 90% after 14 days.

Parameter:

% degradation (DOC removal)

Value:

ca. 23

Sampling time:

42 d

Details on results:

No removal of DOC in the flask containing the sterile medium indicates that no abiotic removal has taken place. Removal of DOC from the test flasks was observed in an additional 2 time points after the 28 day test period (35 and 42 days), however significant removal of DOC was not observed.

Results with reference substance:

The quantity of DOC that is degraded in the inhibition flask (the flask containing the sample and the reference compound, sodium acetate) corresponds to the portion originating from the reference compound. This shows that the test article was not inhibitory to the inoculum.

According to OECD guidelines for testing chemicals a test compound is regarded as easily biodegradable if the loss of DOC within 28 days is greater than 70 %. The pass value has to be reached in a 10-day window within the 28-day period of the test. The 10-day window begins when the degree of biodegradation has reached 10% DOC and must end before day 28 of the test. This criterion is not reached for the test article and therefore Polyol PX cannot be regarded as readily biodegradable.

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

Under the conditions applied during the test, Polyol PX could not be considered readily biodegradable.

Executive summary:

A study was conducted at the laboratories of AnoxKaldnes AB, Lund, Sweden on behalf of Perstorp Speciality Chemicals, Sweden, to investigate the aerobic degradability of an organic compound (Polyox PX). The study was performed according to the method SS-EN ISO 7827:1996/OECD 301 A, which monitors the fate of dissolved organic carbon (DOC) over the course of the study. The inoculum was prepared from activated sludge taken from Klagshamn waste water plant, Sweden and the activated sludge contained 5.9 g suspended solids /L. The DOC concentration was measured for each period (0, 7, 14,21 and 28 days) in each of inoculated flasks used for the test and control samples. According to OECD guidelines for testing chemicals, a test compound is regarded as easily biodegradable if the loss of DOC within 28 days is greater than 70 %. The pass value has to be reached in a 10-day window within the 28-day period of the test.

 

The 10-day window begins when the degree of biodegradation has reached 10% DOC and must end before day 28 of the test. This criterion was not reached for the test article and so Polyol PX cannot be regarded as readily biodegradable. The plateau has not been reached after 42 days, approximately 23% DOC was degraded after 42 days.

Description of key information

The substance Reaction mass of 1,3-Propanediol, 2-(hydroxymethyl)-2 [(methoxymethoxy)methyl]- and 1,3-dioxane-5,5-dimethanol can not be classified as readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater