Ferrocene

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

The Bringmann growth inhibition test could not be used to determine the bacterial toxicity of ferrocene (iron biscyclopentadienyl) since ferrocene concentrations above the solubility in water had to be used in order to achieve saturation of the culture solution. As the Bringmann-Kuhn test is evaluated photometrically (cytochrome measurement), the undissolved solids interfered with the measurement of bacterial density.

We therefore chose an oxygen consumption test developed by HUls AG. This test method also uses the experimental organism Pseudomonas putida. The test runs for about six hours to allow cells to proliferate. This also allows recording of chronic effects.

Ferrocene was tested in concentrations (8.9; 17.5; 44.3; 87.6 mg/l) that are above the water solubility. An emulsifier (nonylphenol + 10 mol ethylene glycol + 5 mol propylene glycol; 1.5 mol/l) was also added.

GLP compliance:

not specified

Vehicle:

yes

Test organisms (species):

Pseudomonas putida

Test type:

static

Water media type:

freshwater

Total exposure duration:

6 h

Nominal and measured concentrations:

8.9, 17.5, 44.3, 87.6mg/L Nominal

Key result

Duration:

6 h

Dose descriptor:

NOEC

Effect conc.:

> 87.6 mg/L

Nominal / measured:

nominal

Basis for effect:

other: O2 consumption

The data listed in the protocol show that in none of the selected concentration levels was an inhibition of oxygen consumption measurable. From this it can be concluded that no inhibition occurs in the saturation range.

Validity criteria fulfilled:

yes

Conclusions:

Ferrocene was tested in a study designed to assess the effect it has on the toxicity to microorganisms (activated sludge). It was found to have a NOEC (6 hr) > 87.6mg/l (respiration rate)

Description of key information

Ferrocene was tested in a study designed to assess the effect it has on the toxicity to microorganisms (activated sludge). It was found to have a NOEC (6 hr) > 87.6mg/l (respiration rate)

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

87.6 mg/L

Additional information

Ferrocene was tested in a study designed to assess the effect it has on the toxicity to microorganisms (activated sludge). It was found to have a NOEC (6 hr) > 87.6mg/l (respiration rate)