Triethoxy(3-thiocyanatopropyl)silane

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

experimental study planned

Study period:

After approval by ECHA

Qualifier:

according to guideline

Guideline:

OECD Guideline 222 (Earthworm Reproduction Test (Eisenia fetida/Eisenia andrei))

Principles of method if other than guideline:

The study is to be conducted with the hydrolysis product of the registered substance, in view of its hydrolysis rate - see IUCLID Section 6.3 for further details of the risk assessment approach. A tiered testing approach is proposed with the OECD 222, 216 and 211 studies to be conducted first in order to establish whether an OECD TG 208 plant test is required, based on the results of the screening approach.

Description of key information

OECD TG 222 Test Proposal

Additional information

In the context of the Integrated Testing Strategy for the terrestrial compartment (ECHA guidance Chapter R.7c, terrestrial hazard classification scheme, Table R.7.11—2) (ECHA 2017) the substance is assigned to the soil Hazard Category 3 (see IUCLID Section 6.3 and CSR Section 7.2 for further details).

In this situation, a screening approach is applied, where the equilibrium partitioning risk assessment approach with an extra factor of ten, in addition to a confirmatory long-term terrestrial test, are to be conducted:

PEC/PNECscreen:

The PEC × 10 / PNECscreen based on the equilibrium partitioning method indicates the substance will have a risk characterisation ratio (RCR) >1. The highest terrestrial RCR is 8.48 in agricultural soil.

Confirmatory long-term test:

An OECD 222 study with earthworms is proposed with the hydrolsis product of the registered substance.

In addition, ECHA guidance Chapter R.7c, Table R.7.11—2 states the following: "If PEC/PNECscreen > 1 or indication of risk from confirmatory long-term soil toxicity test: Conduct long-term toxicity tests according to the standard information requirements Annex IX or X (invertebrates and plants), choose lowest value for derivation of PNECsoil". The PEC/PNECscreen is >1, which indicates that standard information requirements according to Annex IX or X should be conducted. However, a long-term aquatic toxicity study with invertebrates OECD 211 is proposed, which is likely to affect the PEC/PNECscreen. Therefore, it is proposed to review the results of the screening assessment once the OECD 211 and 222 study results are available, before concluding on the need to conduct the OECD 208 plant study.