Glycollic acid

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water and sediment: simulation testing, other

Type of information:

other: Publication

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Principles of method if other than guideline:

Seawater samples were collected from several locations, including bay and river estuary sites, in order to examine the capability of bacteria to metabolise glycolic acid. Chemical assays and measurements of heterotrophic uptake and mineralisation were evaluated. Various methods and their results are described.

Radiolabelling:

yes

Inoculum or test system:

natural water

% Degr.:

66 - 90

Parameter:

radiochem. meas.

Remarks on result:

other: The study qualitatively demonstrates that marine heterotrophic bacteria can metabolise glycolic acid and use it as a source of energy. This indicates that glycolic acid will not persist in estuarine and marine habitats.

Conclusions:

The study qualitatively demonstrates that marine heterotrophic bacteria can metabolise glycolic acid and use it as a source of energy. This indicates that glycolic acid will not persist in estuarine and marine habitats.

Executive summary:

The study reports on measurements of glycolic acid and of heterotrophic activity on glycolic acid in coastal seawater using various methods and¹⁴C-labelled glycolic acid. The paper reports that 2/3 of the colonies of bacteria cultured from seawater on marine agar were capable of taking up and respiring glycolic acid. Mineralisation is reported in ranges from 66 to 90%.

Reference 2

Endpoint:

biodegradation in water and sediment: simulation testing, other

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 306 (Biodegradability in Seawater)

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

other: Sea Water

Duration of test (contact time):

43 d

Initial conc.:

4.08 mg/L

% Degr.:

10

Parameter:

other: Theoretical O2 Demand or measured COD

Sampling time:

1 d

% Degr.:

50

Parameter:

other: Theoretical O2 Demand or measured COD

Sampling time:

2 d

% Degr.:

96

Parameter:

other: Theoretical O2 Demand or measured COD

Sampling time:

28 d

Conclusions:

Biodegradation after 28 days under the stated test conditions was 96%.

Executive summary:

A Biodegradability in Seawater test (OECD 306) was performed on the test substance. The following results were obtained: 1) 1 day to 10% biodegradation (lag phase), 2) 2 days to 50% biodegradation after lag time, and 3) 96% biodegradation after 28 days.

Reference 3

Endpoint:

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

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

Reference 4

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

Description of key information

In accordance with Column 2 adaptation statement of REACH Annex X, Section 9.2, no further investigation of the degradation of the substance and its transformation/degradation products is needed given the chemical safety assessment per Annex I indicates that the substance is not a PBT, is not classified as dangerous, and has low ecological and mammalian toxicity. The primary compartments for environmental exposure are soil and water based on the physical chemical properties and the level III fugacity modelling. The substance is readily biodegradable, which suggests that under intended conditions of use, biodegradation of the test substance and subsequent degradation products will be completely degraded to CO2. The test for biodegradability is considered a stringent test for assessing the biodegradation potential of substances. For these reasons, further biodegradation of this test substance and is transformation/degradation products is not needed.

Additional information

Although not required given the substance is ready biodegradable, the biodegradation in seawater study was included to demonstrate that heterotrophic bacteria contained in natural seawater are capable of taking up and mineralising glycolic acid. Therefore, glycolic acid is not anticipated to persist in the marine environment.