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Administrative data

Link to relevant study record(s)

Description of key information

Short description of key information on bioaccumulation potential result: 
A toxicokinetic statement was drawn up.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential
Absorption rate - oral (%):
100
Absorption rate - dermal (%):
10
Absorption rate - inhalation (%):
100

Additional information

The excerpt from the toxicokinetic statement is:

The concentration of L-alanine in blood is relatively constant. For risk assessment purposes oral absorption

of L-alanine is set at 100%.

L-alanine is of low volatility due to a very low vapour pressure (0.00000283 Pa). From this and from the

particle size it is not expected that L-alanine reaches the nasopharyncheal region or subsequently the

tracheobronchial or pulmonary region in significant amounts.

However, being a very hydrophilic substance with a molecular mass of only 89.09, any L-alanine reaching

the lungs might be absorbed through aqueous pores. For risk assessment purposes, although it is unlikely

that L-alanine will be available to a high extent after inhalation via the lungs due to the low vapour pressure

and high MMAD (Mass median aerodynamic diameter), the inhalation absorption of L-alanine is set at 100%.

L-alanine with high water solubility (166.5 g/L) and the log P value below 0 (-2.74) may be too hydrophilic to

cross the lipid rich environment of the stratum corneum. Therefore, 10% dermal absorption of L-alanine is

proposed for risk assessment purposes.