Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Version / remarks:

from 1992

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

EC Number:

605-460-1

Cas Number:

167004-78-6

Molecular formula:

C11 H20 N O4 P

IUPAC Name:

Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

Details on test material:

Molecular weight: 261 g/mol
Molecular formular: C11H2ONO4P

Study design

Oxygen conditions:

not specified

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: WWTP Franfurt a.M., Sindlingen; filtered Outflow
- Preparation of inoculum for exposure: aerated for 7 d before exposure
- Concentration of sludge: 0.5 ml/L

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

2.32 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

1.52 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: composition as described in the guideline EU Method C4, mineral medium
- Test temperature: 22 °C +/- 1°C
- pH: 7.3
- pH adjusted: yes

TEST SYSTEM
- Culturing apparatus: thermostated incubator
- Measuring equipment: BOD Flasks
- Test performed in closed vessels: yes

SAMPLING
- Sampling frequency: every 7 days
- Sampling method: one replicate was sacrificed each, dissolved oxygen was determined in three test vessels

CONTROL AND BLANK SYSTEM
- Inoculum blank: medium + inoculum
- Toxicity control: with reference substance

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

4

Sampling time:

7 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

12

Sampling time:

14 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

14

Sampling time:

21 d

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

12

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

Degradation of the reference substance leads to O2 consumption of >60 % theoret. O2 consumption within 14 days.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

In an experimental study according to OECD guideline 301D and GLP, the test item was found to be not readily biodegradable.

Executive summary:

An experimental study according to OECD 301D and GLP regulations was conducted to assess the readily biodegradability of the test item. The inoculum consisting of acitvated sludge from a domestic sewage plant was eposed to a concentration of 1,52 mg/L and 2,32 mg/L test item for a test period of 28 d.

The consumed O2 was measured electrometric in BOD bottles every 7 days. After 28 d 12 % were degraded. Therfore the substance is not readily biodegradble according to OECD criteria.