1,1''-isopropylidenediferrocene

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June to July 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Read across data is presented from the structurally related substance, 1,1'-Bis(ferrocenyl)octane, CAS Number 501410-94-2, EC Number 479-710-1. This substance bears a close similarity to 1,1''-isopropylidenediferrocene, CAS Number 12609-95-9, EC Number 235-719-0, the distinction being that the alkyl bridging functionality between the two ferrocene moieties is an octyl derivative as opposed to an isopropyl derivative.

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

Identity and concentration of auxiliary solvent for dispersal: Aceton 100 mg/L

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Details on test organisms:

The algae were supplied by the "Laboratory of Hidrobiology, Szazhalombatta", H-2441 Szazhalombatta, Hungary.

The stock cultures are small algal cultures that are planted on agar regularly. These are transferred to fresh medium at least once every two months under standardised conditions according to the test guidelines.

The pre-culture is intended to give an amount of algae suitable for the inoculation of test cultures. The pre-culture was prepared with Algal Mineral Salts Culture Medium, incubated under the conditions of the test and used when still exponentially growing, normally after an incubation period of about three days.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

23 +/- 2 degrees C

pH:

8.86 to 8.9 at the start of the test and 9.45 to 9.51 at the end of the test.

Reference substance (positive control):

yes

Remarks:

Potassium Dichromate

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.36 mg/L

Basis for effect:

biomass

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.36 mg/L

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 0.36 mg/L

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 0.36 mg/L

Basis for effect:

biomass

Conclusions:

In an OECD 201, 1,1'-Bis(ferrocenyl)octan, has an 72hour EC50 of > 0.36mg/L (measured) to Algae. The NOEC was 0.36mg/L. The nominal value added to the water of 0.5mg/L is 10x the water solubility of the molecule.

Executive summary:

The short-term toxicity to aquatic algae of 1,1'-Bis(ferrocenyl)octane, CAS Number 501410-94-2, EC Number 479-710-1was investigated in accordance with the standardised guideline OECD 201.

An OECD 201 study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results was performed on 1,1'-Bis(ferrocenyl)octane, CAS Number 501410-94-2, EC Number 479-710-1.

The study was assigned a reliability score of 1 in accordance with the criteria for assessing data quality set forth by Klimisch et al. (1997).

This substance is considered to be sufficiently close in structural integrity to 1,1''-isopropylidenediferrocene, CAS Number 12609-95-9, EC Number 235-719-0 so as to justify valid read across.

Under the conditions of the study 1,1'-Bis(ferrocenyl)octan, has an 72hour EC50 of > 0.36mg/L (measured) to Algae. The NOEC was 0.36mg/L. The nominal value added to the water of 0.5mg/L is 10x the water solubility of the molecule.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

no

Specific details on test material used for the study:

Read across data is presented from the structurally related substance, iron(2+) dicyclopenta-2,4-dienide (ferrocene), CAS Number 102-54-5, EC Number 203-039-3. This substance bears a close similarity to 1,1''-isopropylidenediferrocene, CAS Number 12609-95-9, EC Number 235-719-0. Therefore, it is considered that read-across is valid.

Vehicle:

yes

Remarks:

Acetone

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.14 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Remarks on result:

other: Diluted in Acetone

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

1.03 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Remarks on result:

other: Diluted in Acetone

Conclusions:

In a Study performed equivalent or similar to OECD Guideline 201, ferrocene produced an EC50 (72hr) = 1.03 mg/l and an EC10 (72hr) = 0.14 mg/l. The values ​​of the algal growth inhibition are in accordance with the data in and of the same magnitude as the values ​​ for daphnia acute toxicity. The samples were diluted in acetone to enable solubilisation.

Executive summary:

The short-term toxicity to aquatic algae of iron(2+) dicyclopenta-2,4-dienide (ferrocene), CAS Number 102-54-5, EC Number 203-039-3 was investigated in a study which was equivalent or similar to guideline OECD 201.

The study was assigned a reliability score of 2 in accordance with the criteria for assessing data quality set forth by Klimisch et al. (1997).

This substance is considered to be sufficiently close in structural integrity to 1,1''-isopropylidenediferrocene, CAS Number 12609-95-9, EC Number 235-719-0 so as to justify valid read across.

In this study, ferrocene produced an EC50 (72hr) = 1.03 mg/l and an EC10 (72hr) = 0.14 mg/l. The values ​​of the algal growth inhibition are in accordance with the data in and of the same magnitude as the values ​​ for daphnia acute toxicity. The samples were diluted in acetone to enable solubilisation.

Description of key information

Two studies are presented on structurally related substances as valid read across candidates: 1,1'-Bis(ferrocenyl)octane, CAS Number 501410-94-2, EC Number 479-710-1 (OECD 202) and Iron(2+) dicyclopenta-2,4-dienide (Ferrocene), CAS Number 102-54-5, EC Number 203-039-3 (equivalent or similar to OECD 202).

In an OECD 201, 1,1'-Bis(ferrocenyl)octan, has an 72hour EC50 of > 0.36mg/L (measured) to Algae. The NOEC was 0.36mg/L. The nominal value added to the water of 0.5mg/L is 10x the water solubility of the molecule.

In the case of iron (2 +) dicyclopenta-2,4 -dienide (ferrocene), CAS Number 102 -54 -5, EC Number 203 -039 -3, a study performed that was equivalent or similar to OECD Guideline 201 an EC50 (72hr) = 1.03 mg/l and an EC10 (72hr) = 0.14 mg/l were observed.

Key value for chemical safety assessment

EC50 for freshwater algae:

0.36 mg/L