(1-hydroxyethylidene)bisphosphonic acid, potassium salt

Bioaccumulation: terrestrial

Administrative data

Endpoint:

bioaccumulation: terrestrial

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with generally accepted scientific standards and described in sufficient detail.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Materials and methods

Principles of method if other than guideline:

Physical effects and bioaccumulation (roots, stems, leaves and fruit)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Etidronic acid

EC Number:

220-552-8

EC Name:

Etidronic acid

Cas Number:

2809-21-4

Molecular formula:

C2H8O7P2

IUPAC Name:

(1-hydroxyethylidene)bisphosphonic acid

Test substrate

Details on preparation and application of test substrate:

Test plants were incubated and fed with test substance via nutrient solution at a nominal concentration of 3.0 mg/l
(measured concentrations 2.7 - 3.3 mg/l, mean 3.0 mg/l; equivalent to 1.8 mg active acid/l). Control plants were fed
nutrient solution only.

The test concentration was chosen as it is the highest recommended application rate for use in irrigation water.

Test organisms

Test organisms (species):

other: Strawberry plant - Fragaria vesca

Study design

Total exposure / uptake duration:

33 d

Test conditions

Test temperature:

24 °C (20 - 30 °C)

Moisture:

Humidity: = 60%

Results and discussion

Bioconcentration factor

Type:

BCF

Value:

13 dimensionless

Basis:

other: roots

Any other information on results incl. tables

12% of the treatment plants died during the study period.
There were no mortalities amongst control plants.

Minor morphological abnormalities were observed in control and treatment plants. These were not attributed to the treatment.

Exposure to the test substance was confirmed by analysis of roots, giving a mean measured concentration of 39 mg/kg,
equivalent to a BCF of 13, the only quantifiable value obtained. Analysis of stems, leaves and fruit showed
occasional instances of measurable amounts of ESI-50.

Concentration (mg/l) in nutrient solution was 3.0 mg/l and <0.330 mg/l in controls.

        Concentration (mg/kg)       
          Control    Test
Sand       <4.97    <4.93
Roots      <17.3     39
Stems     <16.9    <26.1
Leaves    <15.0    <13.0
Fruit      <4.25    <4.24

Applicant's summary and conclusion

Conclusions:

ESI-50 has little potential to bioaccumulate in strawberry plants.