Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

One valid ready biodegradability test results is available for di (2 -hydroxypropyl)tallow amine. The biodegradation percentages reached at day 28 in Closed Bottle test is 62. All primary fatty amine propoxylates with alkyl chains ranging van 10 to 18 unsaturated/saturated are therefore anticipated to be readily biodegradable. Besides to degradation by microorganisms also degradation in other biota like fish are anticipated for primary fatty amine propoxylates. Metabolic rates in fish were measured for 1 -Hexadecanamine (n-Primary C16amine) using an in vitro method with carp hepatocytes (Bernhard et al, 2006). The Km was estimated to be 0.152 1/d assuming only arterial blood supply to the liver, whereas a rate of 1.024 L/d was estimated considering both arterial and a portal blood supplies. Even the rate of 0.152 1/d leads to a fast metabolism in fish and results in a low bioconcentration.

The Table below summarizes half-lives derived through default values and a simulation study.

 

Table Summary of degradation rate constants in various (eco) systems based the ready biodegradability of primary fatty amine propoxylates.

(Eco) system

Method

Half-life

Surface water

TGD default value

15 days half-life

Surface water sediment

Determined by read across

33.8 days half-life

Marine water

TGD default value

50 days half-life

Soils

Determined by read across

33.8 days half-lifea

Degradation in sewage treatment plants

Determined by read across

>99.97% removal primarily by biodegradation

 aHalf-life of the fraction dissolved in the water phase is expected to be in the order of a few days.