Tris[2-[2-(2-methoxyethoxy)ethoxy]ethyl] orthoborate

Endpoint summary

Additional information

In accordance with column 2 of REACH Annex IX (section 9.4) and Annex X (section 9.4), tests for the effects on terrestrial organisms "do not need to be conducted if direct and indirect exposure of the soil compartment is unlikely". The Guidance on information requirements and chemical safety assessment, Chapter R.7C: Endpoint specific guidance, sections R.7.11.2.1c and R.7.11.2.1d, pages 109 and 110, respectively, specifies that "in the case of ready biodegradable substances which are not directly applied to the soil it is generally assumed that they will not enter the terrestrial environment and as such there is no need for testing of soil organisms".

B-TEGME will not be applied to soil, is readily biodegradable, hydrolyses quickly and has a low potential for bioaccumulation, i. e., the log Pow is << 3 and the soil organic carbon partition coefficient Koc is 0.008. Therefore, it is very unlikely that B-TEGME will enter the terrestrial compartment directly or indirectly from sewage treatment plants. Furthermore, it is likely that the hazard from B-TEGME for terrestrial orgnanisms is low since B-TEGME is not toxic to aquatic (freshwater) organisms. A PNEC soil of 0.0283 mg B-TEGME/kg soil dw was calculated using the aquatic PNEC and equilibrium partitioning method. Based on these characteristics, B-TEGME is not expected to cause adverse effects on organisms of the terrestrial habitat.

Further arguments for waiving the terrestrial toxicity studies comes from the criteria for "no hazard" which are specified in the draft guidance for Chapter B8 (Guidance on information requirements and chemical safety assessment, Part B: Hazard Assessment , Draft new chapter B.8 Scope of Exposure Assessment, draft version 23 February 2010, page 12).

"Absence of significant ecotoxicological effects (and thus "no hazard") may be concluded if all of the following criteria are met:

o The intrinsic properties of the substance are well below the criteria for classification as dangerous (hazardous) in accordance with Directive 67/548/EEC (or Regulation (EC) No 1272/2008), using all available data. i.e.:

- the substance has a very low potential to bioaccumulate in aquatic species (e.g. fish) i.e. experimentally determined BCF < 10. For organic substances an alternative criterion, log Kow < 2.0 can be applied

- the substance is readily biodegradable (this criterion does not apply to inorganic substances)

- the aquatic toxicity has to fulfil both of the following criteria:

- acute, short-term E(L)C50 > 1000 mg/l or> water solubility,or no significant adverse effects recorded at 100 mg/l in acute, short-term aquatic toxicity tests and validated QSAR data showing acute effects (E(L)C50) > 1000 mg/l

- chronic long-term NOEC (or equivalent ECx; e.g. EC10) > 10 mg/L

o The substance shall not have adverse effects on terrestrial organisms, meaning that no adverse effects are reported in any of the tests required under Annex IX of REACH at the maximum test concentrations prescribed by the respective OECD guidelines.

It might be the case that no studies on terrestrial organisms are available based on considerations that direct and indirect exposure of the soil compartment is unlikely. If a registrant has adapted the standard information requirements, this has to be well documented and justified in the registration dossier. Thus, the justification given for waiving the tests should either refer either to exposure considerations or it should be based on relevant substance properties, such as partitioning behaviour.

o The substance shall not be identified as having or be suspected to have endocrine activity from in vivo or in vitro tests, nor from the application of relevant (Q)SAR models or other structural alerts which may give rise any concern for endocrine-disrupting properties (DG Environment, ENV.D4./ETU/2005/0028r; http:/ec.europa.eu/ environment/endocrine/documents/final_report_2007.pdf)."

These requirements are addressed for B-TEGME as follows:

o Intrinsic properties:

- B-TEGME has a log Kow of -4.37 and hence a very low risk for bioaccumulation

- B-TEGME is readily biodegradable  

-  The EC50 values obtained in the acute, short term aquatic tests were > 100 mg B-TEGME/L

- QSAR calculations with ECOSAR (v1.00) as implemented in EPIwin 4.0 support the tests as they indicate that the EC50 values for fish daphnids and algae are >>1000 mg B-TEGME/L (see page 3 of the printout attached to this waiver)

- The long-term NOEC from algae is >> 10 mg B-TEGME/L

o B-TEGME is not expected to have adverse effects on terrestrial organisms (see above)

o B-TEGME is not identified as having or be suspected to have endocrine activity from in vivo or in vitro tests

These arguments support that there is no ecotoxicological hazard arising from B-TEGME and that the hazard is already appropriately described with the available studies. This supports the above argumentation that terrestrial toxicity tests are not needed for B-TEGME.