Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

toxicity to microorganisms, other
toxicity control from ready biodegradability study
Type of information:
experimental study
Adequacy of study:
key study
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Data based on the inhibition control of a ready biodegradability guideline study. This approach is in accordance with the Guidance on information requirements and chemical safety assessment (Chapter R.7b: Endpoint specific guidance, ECHA 2017).
Reason / purpose for cross-reference:
reference to same study
according to guideline
other: OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
Version / remarks:
July 1992
GLP compliance:
yes (incl. QA statement)
Landesamt für Umwelt Baden-Württemberg, Germany
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 164 mL of the test item stock solution with 48.1 mg/L and a pH of 7.5 and 21.0 mg of the reference substance were added into the toxicity control vessel (corresponding to a concentration of 200 mg/L* COD).
Test organisms (species):
activated sludge of a predominantly domestic sewage
Details on inoculum:
- Source of inoculum/activated sludge: municipal wastewater treatment plant AZV Breisgauer Bucht (predominantly domestic wastewater), sampling date of activated sludge: 26 July 2022,
- Preparation of inoculum for exposure: The activated sludge was washed twice with tap water by settling the sludge, decanting the supernatant and re-suspending the sludge. The sludge was aerated at ambient temperature until use.
- Concentration of sludge: 30 mg d.s./L
- Dry solids concentration: 4.27 g/L (drying at 105°C for 5 hours)
- Water filtered: no
Test type:
Water media type:
Limit test:
Total exposure duration:
14 d
Remarks on exposure duration:
Overall exposure was 28 d but the inhibition effect is evaluated after 14 d.
Test temperature:
21.3 – 21.5°C
Details on test conditions:
- Composition of medium: according to the guideline 301 F
- Solubilising agent: none
- Test temperature: 21.3 – 21.5°C throughout the whole study and therefore within the required range of 22 ± 2°C
- pH: 7.5 (at the beginning and termination of test)
- pH adjusted: The pH of the mineral medium was 7.7 and was therefore adjusted to 7.5 with HCl. After preparation of test solutions, no pH adjustment was needed (pH: 7.5)
- Aeration of dilution water: yes, at least half an hour
- Susspended solids concentration: 30 mg d.s./L

- Culturing apparatus: OxiTop® (WTW / Xylem)
- Method used to create aerobic conditions: inoculum was aerated until use (see details on inoculum and medium/test solutions were prepared under oxic conditions)
- Measuring equipment: Sensomat (AQUALYTIC®)
- Test performed in closed vessels: yes
- Test performed in open system: no
- Details of trap for CO2 if used: bottles were equiped with rubber quiver inserts for NaOH pellets, which absorb the carbon dioxide produced.

- Sampling frequency and method: Every 112 minutes, the current pressure was measured and stored by each measuring head.
- Sterility check if applicable: not applicable
- Sample storage before analysis: no

- Inoculum blank: 3 replicates (only inoculum)
- Reference substance: 3 replicates (concentration corresponding to 99.8 mg COD/L)
- Toxicity control: 1 replicate (48.1 mg/L test item and 21 mg reference substance corresponding to a concentration of 200 mg/L COD)
Reference substance (positive control):
acetic acid, sodium salt
14 d
Dose descriptor:
Effect conc.:
>= 48.1 mg/L
Nominal / measured:
Conc. based on:
test mat.
Basis for effect:
other: BOD measurements and subsequent calculation of chemical oxygen demand
Remarks on result:
other: Result of toxicity control from ready biodegradability test
Details on results:
The degradation of the toxicity control after 14 days was >25%. Therefore, the test item had no inhibitory effect on the inoculum according to the criterion of the guideline OECD 301 F.
Results with reference substance (positive control):
The reference compound sodium acetate reached the pass level of 60% COD within 5 days.

Since more than 25% degradation occurred in the toxicity control after 14 d (48.9 on Day 4 and >80% on Day 12), the substance is with high probability not toxic to aquatic microorganisms. The test item concentration in the toxicity control of 48.1 mg/L can be used as NOEC value for the toxicity to aquatic microorganisms.

Description of key information

NOEC (14 d) ≥ 48.1 mg/L (nominal, toxicity control of OECD 301 F)

Key value for chemical safety assessment

Additional information

Since no studies on the toxicity to aquatic microorganisms are available a ready biodegradability study is used to derive a NOEC for the toxicity to aquatic microorganisms. If a compound degrades well in a ready biodegradability test or does not inhibit the degradation of a positive control at a certain concentration, this concentration can be used as a NOEC value. This approach is in accordance with the Guidance on information requirements and chemical safety assessment (Chapter R.7b: Endpoint specific guidance, ECHA 2017).


A substance can be assumed to be not inhibitory to aquatic microorganisms, if in the toxicity control of a ready biodegradation test, more than 25% degradation based on oxygen demand (BOD/ThOD) occurred within 14 days (OECD guideline 301). For Octanoic acid, monoester with glycerol (CAS 26402-26-6) a biodegradation test according to the OECD guideline 301 F is available (and GLP). The test includes a toxicity control, which contains 48.1 mg/L of Octanoic acid, monoester with glycerol and 21 mg/L of the reference material acetic acid, sodium salt (corresponding to 199 mg/L COD). The toxicity control attained 48.9% biodegradation on Day 4 and >80% on Day 12 of incubation. Hence, the substance is not considered toxic to aquatic microorganisms in the toxicity control and the test item concentration of 48.1 mg/L (nominal) can be used as NOEC.