Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Due to its high adsorption and low toxicity to aquatic organisms, DTPMP was assigned to soil hazard category 3 (R.7.11.6, ECHA 2017). The aquatic studies indicate that vertebrate and invertebrate toxicity is relatively comparable (short-term E(L)C50values > 100 mg active acid/L and long-term NOECs ≥ 25 mg active acid/L), while algal studies are complicated by complexation effects. In line with the ITS in R.11.6 (ECHA 2017) a screening assessment was conducted, based on the equilibrium partitioning method (PEC * 10 / PNECscreen) and a long-term study to soil invertebrates (OECD 222) has been commissioned, to be conducted with DTPMP(5-7Na) and read across to the DTPMP(1-3Na) registration substance.


The study report is not expected to be available in time for the ECHA test proposal evaluation decision deadline of 19th February 2021, therefore a dossier update will be submitted by July 2021 and results from this study will be used in due course to derive a new PNECsoil value for the chemical safety assessment. Please refer to IUCLID Section 6.3.1 and Section 7.2.1 of the CSR for further information.

Additional information

DTPMP and their salts are highly adsorbing to soil and soil mineral substrates. The nature of the adsorption is believed to be primarily due to interaction with inorganic substrate or generalised surface interactions. High adsorption is consistent with similar behaviour seen for the analogues HMDTMP, ATMP-N-oxide and ATMP, and other common complexing agents such as EDTA. By reference to findings with other similar substances, the binding occurs very rapidly and is effectively irreversible. For environmental fate purposes in exposure assessment this is assessed as a removal process.


Please refer to Annex 4 of the CSR and IUCLID Section 13 for further information on the read-across within the DTPMP category.