Registration Dossier

Diss Factsheets

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
no hazard identified

Marine water

Hazard assessment conclusion:
no hazard identified

STP

Hazard assessment conclusion:
no hazard identified

Sediment (freshwater)

Hazard assessment conclusion:
no hazard identified

Sediment (marine water)

Hazard assessment conclusion:
no hazard identified

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
no hazard identified

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

Conclusion on classification

KEY PARAMETERS FOR CLASSIFICATION


The registered substance 3-(triethoxysilyl)-N-[3-(triethoxysilyl)propyl]-1-propanamine (CAS 13497-18-2) hydrolyses rapidly in contact with water (DT50 = 11.9 h at pH 7 and 20 °C, OECD 111) to 3-(trihydroxysilyl)-N-[3-(hydroxysilyl)propyl]-1-propanamine and ethanol. REACH guidance R.16 states that “for substances where hydrolytic DT50 is less than 12 h, environmental effects are likely to be attributed to the hydrolysis product rather than to the parent itself” (ECHA, 2016). The environmental hazard and risk assessment is therefore based on the silanol hydrolysis product, i.e. 3-(trihydroxysilyl)-N-[3-(hydroxysilyl)propyl]-1-propanamine. The other, alcohol hydrolysis product, ethanol, is not expected to affect the environmental hazard profile of the parent substance (OECD SIDS, 2004). However, since the hydrolysis half-life of the registered compound is close to the cut-off value of 12 hours and for the sake of completeness, the environmental hazard and risk assessment in this dossier also considers the parent compound.


 


Abiotic degradation - Hydrolysis


DT50 = 11.9 h at pH 7 and 20 °C (OECD 111)


 


Biodegradation in water


Parent: Not readily biodegradable (62 - 64.5% in 28 d, OECD 301 C and OECD 306)


Silanol HP: Not readily biodegradable (62 - 64.5% in 28 d, OECD 301 C and OECD 306)


 


Bioaccumulation


log Kow (parent) = 3.1 (20 °C, QSAR)


log Kow (silanol hydrolysis product) = -4.0 (20°C, QSAR)


BCF (silanol hydrolysis product) < 4.2 (RA CAS No. 82985 -35 -1)


 


Aquatic acute toxicity


Fish


LC50 (96 h) > 200 mg/L (nominal, Scophthalmus maximus, OECD 203)


Aquatic invertebrates


EC50 (48 h) > 151.9 mg/L (meas. init., Acartia tonsa, ISO 14669)


Aquatic algae


ErC50 (72 h) = 125 mg/L (nominal, marine alga Phaeodactylum tricornutum, ISO 10235)


 


Aquatic chronic toxicity


Aquatic algae


ErC10 (72 h) = 68 mg/L (nominal, marine alga Phaeodactylum tricornutum, ISO 10235)


 


Classification according to CLP


3-(triethoxysilyl)-N-[3-(triethoxysilyl)propyl]-1-propanamine (CAS 13497-18-2) hydrolyses rapidly under environmental conditions (DT50 = 11.9 h at pH 7 and 20 °C) to form the silanol hydrolysis product 3-(trihydroxysilyl)-N-[3-(hydroxysilyl)propyl]-1-propanamine


and ethanol. The registered compound and its silanol hydrolysis product are not considered to be readily biodegradable, while the alcohol hydrolysis product ethanol is considered to be readily biodegradable (OECD SIDS, 2004). Acute toxicity data are available for all three trophic levels (fish, aquatic invertebrates, algae) on the registered compound. The L(E)C50 effect values are >100 mg/L in all three trophic levels. Due to the rapid hydrolysis of the parent compound and the duration of the acute aquatic toxicity tests (48 to 96 h), the organisms can be expected to be predominantly exposed to the hydrolysis products of the registered compound. Because the alcohol hydrolysis product ethanol is known for its low environmental hazard with effect values well above the herein tested concentrations (OECD SIDS, 2004), ethanol can be disregarded in the overall environmental hazard assessment. Therefore, 3-(triethoxysilyl)-N-[3-(triethoxysilyl)propyl]-1-propanamine (CAS No. 13497-18-2) and its silanol hydrolysis product 3-(trihydroxysilyl)-N-[3-(hydroxysilyl)propyl]-1-propanamine do not need to be classified and labeled according to the consolidated version of Regulation (EC) No 1272/2008 and further amendments (ATPs).