Reaction products of sulphuric acid, rock phosphate and humic acids, potassium salts

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Well documented scientific publication, but method not validated The rationale to use data from individual constituents and components of the complex is explained in chapter 1 of the CSR and in the adjacent "read-across document

Data source

Reference

Reference Type:

publication

Title:

Lead and zinc bioavailability to Eisenia fetida after phosphorus amendment to repository soils

Author:

Ownby, D.R., Galvan, K.A., Lydy, M.J.

Year:

2005

Bibliographic source:

Environ. Pollut. 136, 315-321.

Materials and methods

Principles of method if other than guideline:

Phosphorus fertiliser was added to two contaminated soils and bioavailability of heavy metasl as well as toxicity to earthworm Eisenia fetida was examined.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Triple Superphosphate (TSP)

IUPAC Name:

Triple Superphosphate (TSP)

Constituent 2

Reference substance name:

Superphosphates, concd.

EC Number:

266-030-3

EC Name:

Superphosphates, concd.

Cas Number:

65996-95-4

Molecular formula:

not applicable (a generic molecular formula cannot be provided for this specific multi-constituent substance)

IUPAC Name:

Superphosphates, concd.

Details on test material:

TSP was bought from Voluntary Purchasing Group, Bonham TX, USA. In addition, rock phosphate was tested (IMC Feed Ingredients, Lake Forest, IL, USA).

Sampling and analysis

Analytical monitoring:

no

Test substrate

Vehicle:

no

Details on preparation and application of test substrate:

Test soils were from two different heavy metal-contaminated sites in the USA, with similar carbon content and pH. Soils were homogenised and sieved through a 2mm sieve.

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Study design

Study type:

semi-field study

Substrate type:

natural soil

Limit test:

no

Total exposure duration:

96 h

Test conditions

Test temperature:

20 °C

pH:

pH was variied between 5.4 and 6.5 to examine the influence of pH ontoxicity and on bioavailability of Pb and Zn.

Moisture:

approx. 20%, soils were kept moist by adding deionised water

Details on test conditions:

continuous light

Nominal and measured concentrations:

nominal concentrations: TSP and rock phosphate tested at concentrations of 5000 and 15000 mg P/kg soil.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

5 000 mg/kg soil ww

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

phosphorous

Basis for effect:

mortality

Remarks on result:

other: at pH 6.4

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

15 000 mg/kg soil ww

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

phosphorous

Basis for effect:

mortality

Remarks on result:

other: at pH 6.5

Details on results:

Higher mortality after lowering of pH by phosphoric acid, but unclear whether P from phosphoric acid was included in concentrations given

Any other information on results incl. tables

TSP amendment (5000 mg P/kg soil) resulted in a significant reduction of bioaccumulation of Pb and Zn. Rock phosphate (5000 mg P/kg soil)

reduced significantly the uptake of Zn in earthworms:

Bioaccumulation factors in steady state (after 96h) (Cearthworm/Csoil) for 1 soil type (similar results for second soil):

Pb

control: 0.27+-0.03

TSP: 0.02+-0.01

rock phosphate: 0.32+-0.01

Zn:

Control: 0.21+-0.03

TSP: 0.09+-0.04

rock phosphate: 0.12+-0.01

Applicant's summary and conclusion

Conclusions:

Amendment of contaminated soils with TSP reduced availability of Pb and Zn to earthworms. Increased mortality of earthworms was observed after 96h at concentrations >5000 mg P/kg soil. Similar results were obtained with rock phosphates, although rock phosphate only reduced availability of Pb and not that of Zn.

Executive summary:

Amendment of contaminated soils with TSP reduced availability of Pb and Zn to earthworms. Increased mortality of earthworms was observed after 96h at concentrations >5000 mg P/kg soil. Similar results were obtained with rock phosphates, although rock phosphate only reduced availability of Pb and not that of Zn.