(1-hydroxyethylidene)bisphosphonic acid, potassium salt

Phototransformation in water

Administrative data

Endpoint:

phototransformation in water

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Data source

Reference

Reference Type:

publication

Title:

Properties of Hydroxyethane Diphosphonate affecting its Environmental Fate: Degradability, Sludge Adsorption, Mobility in Soils, and Bioconcentration

Author:

Steber, J. and Wierich, P.

Year:

1986

Bibliographic source:

Chemosphere 15:7 (1986), 929-945

Materials and methods

Study type:

other: direct photolysis plus biotic degradation

Principles of method if other than guideline:

Exposure of 14C-labelled HEDP in closed flasks; 14CO2 formed was subsequently trapped in ethanolamine by flushing the flasks with nitrogen (4 h; 1 l/h).  Thereafter, test solutions were inoculated and incubated in the dark "post-incubation"). 14C-biomass was determined at the end of incubation as the difference of radioactivity in test suspension and centrifuged solution.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Disodium dihydrogen (1-hydroxyethylidene)bisphosphonate

EC Number:

231-025-7

EC Name:

Disodium dihydrogen (1-hydroxyethylidene)bisphosphonate

Cas Number:

7414-83-7

Molecular formula:

C2H8O7P2.2Na

IUPAC Name:

disodium dihydrogen (1-hydroxyethane-1,1-diyl)bis(phosphonate)

Test material form:

not specified

Study design

Radiolabelling:

yes

Light source:

Xenon lamp

Remarks:

Suntest (Hanau Heraeus GmbH, Germany); light intensity 5000 lux

Duration of test at given test condition

Initial conc. measured:

0.2 mg/L

Results and discussion

% Degradation

% Degradation 1

Test condition:

Direct photolysis

% Degradation 2

Test condition:

Indirect photolysis

Any other information on results incl. tables

14CO2-evolution from 14C-HEDP after photodegradation and subsequent biodegradation of the 14C-product formed (i.e. acetate)

Testconcentration: 0.2 mg/l (nominal initial concentration)

14CO2-evolution (% of initial radioactivity)

MEDIUM   % DURING EXPOSURE    % AFTER POST-INCUBATION
-----------------------------------------------------------
AAP, 3 days       4                   26
AAP, 7 days      17                   67

AAP:
mineral salts medium according to US EPA; Algal Assay
Procedure: Bottle Test. National Environmental Research
Center, Corvallis, Oregon, 1971