hydronium;iron(3+);hexahydroxide;disulfate

Toxicity to soil macroorganisms except arthropods

Description of key information

No relevant effects

Additional information

This endpoint is covered by the category approach for dissociating, inorganic and non-toxic iron compounds (please see the section on physical and chemical properties for the category justification/report format).

Testing for this endpoint has been waived in accordance with column 2 and Annex XI, part 3, restrictions.

There are no standard terrestrial toxicity tests reported in the literature, but results from several studies investigating effects of soluble iron salts applied directly to the soils are known from the literature. Such direct exposure of soil macroorganisms to iron salts can be excluded in the supported uses and is therefore not in contradiction to the assessed absence of environmental toxicity of the submission item. Thus these experiments are not relevant as this exposure path is irrelevant for effects of the submission item to the environmental life.

A 75 day study of the effects iron trichloride (ferric chloride) on the earthworm (Octalasion complanatum) was conducted by Totaro et al (1992) in an indoor laboratory site with worms collected from a natural population. The results, expressed as measured Fe concentrations in the soil, showed that individual weight was reduced by exposure to a concentration of 27-42 g Fe/kg soil dw. Juvenile abundance was unaffected at a concentration of 27-42 g Fe/kg soil dw. The total biomass of the population was reduced by exposure to a concentration of 27-35 g/kg soil dw.

The effects on growth and the bioaccumulation of five elements (cadmium, copper, iron, lead and zinc) in earthworms (Lumbricus terrestris) from unfortified soils was investigated by Rida (1996). Elevated trace element concentrations reduced earthworm growth, but no quantified endpoints were reported.

A 75 day study with iron trichloride was conducted in an indoor laboratory site with the Brown gardensnail (Helix aspersa). Snails were exposed to the test substance in soil for 75 days and the numbers of adults and juveniles determined on day 25, 50 and 75 (termination) of the test. Biomass (individuals and total) was determined only on day 75. Individual weight was reduced by exposure to a measured concentration of 27-42 g Fe/kg but was unaffected by exposure to 27-30 g Fe/kg soil dw. Juvenile abundance was unaffected at either concentration (Totaro et al 1992).

• Rida AM (1996). Growth and trace element concentration in the earthworm and plants in non-contaminated soils and soil contaminated with cadmium, copper, iron, lead, and tin: Soil-earthworm interactions. Soil Biol. Biochem. 28(8):1029-35
• Totaro E A, Lucadamo L, Coppa T, Turano C, Gervasi R (1992). Effects of Iron Pollution on Macroinvertebrates Promoting Organic Matter Transformation in Soils of Presila Cosentina (Italy). DOI 10.1007/BF00395456 Biol Fertil Soils 14(4):223-9.