Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Justification for type of information:
The study related to the screening test of biodegradation in water was not deemed necessary as a biodegradation test in seawater is available. The main use of the substance is in offshore activities, therefore seawater has been considered the most appropriate media of the study.
Cross-reference
Reason / purpose:
data waiving: supporting information
Reference
Endpoint:
biodegradation in water: simulation testing on ultimate degradation in surface water
Type of information:
experimental study
Adequacy of study:
key study
Study period:
20 days, August, 2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
Standard sea-water study required for use of chemical substances in off-shore applications.
Qualifier:
according to
Guideline:
OECD Guideline 306 (Biodegradability in Seawater)
GLP compliance:
not specified
Radiolabelling:
no
Oxygen conditions:
aerobic
Inoculum or test system:
natural water: marine
Details on source and properties of surface water:
Seawater was buffered with 1 mL per liter of pH 7.2 Phosphate Buffer Solution. Trace inorganic nutrient solutions were added in corresponding 1 mL per liter volumes. In addition, 10 mg of Hach 2533 nitrification inhibitor per liter of dilution water was added to minimize possible interference caused by the oxidation of nitrogenous compounds by potential nitrifying microorganism.
Duration of test (contact time):
28 d
Initial conc.:
2 mg/L
Reference substance:
other: sodium acetate
Key result
% Degr.:
ca. 70
Parameter:
O2 consumption
Sampling time:
20 d
Transformation products:
not measured

The chimica oxygen demand (COD) for Formaldehyde, reaction products with ethylenediamine was determined to be 0.71 mg O2 per mg substance. The maximum percent biodegradation for Formaldehyde, reaction products with ethylenediamine of 70% was observed on days 20 and 28. The sodium acetate 2 mg/L reference control achieved greater than 60% biodegradation within the 28 day test period i.e. maxium biodegradation of 103% was observed on day 13. Dissolved oxygen depletion in the seawater controls remained within the test guideline of 30%; on day 28 a maximum dissolved oxygen depletion of 6.8% occurred (control oxygen levels had decreased from 7.4 mg/L on day 0, to 6.9 mg/L on day 28).

Examination of control seawater and seawater containing 2 mg/L ofFormaldehyde, reaction products with ethylenediaminefor possible nitrite (NO2 and NO3) formation was conducted on days 27 and 28. No evidence of nitrification was evident; nitrite and nitrate levels for exposure bottles were at or below those of the seawater control at these times.

Validity criteria fulfilled:
yes
Conclusions:
The chimica oxygen demand (COD) for Formaldehyde, reaction products with ethylenediamine was determined to be 0.71 mg O2 per mg substance. The maximum percent biodegradation for Formaldehyde, reaction products with ethylenediamine of 70% was observed on days 20 and 28.
Considered biodegradable.

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion