Reaction mass of Amines, N-tallow alkyltrimethylenedi-, mono(2-ethylhexanoates), Amines, N-tallow alkyltrimethylenedi-, acetates and n-tallow-1,3-diaminopropane ditallate

Phototransformation in air

Link to relevant study record(s)

Reference

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Half-life in air estimated using the EPIsuite QSAR

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Guideline:

other:

Principles of method if other than guideline:

The Atmospheric Oxidation Program for Microsoft Windows (AOPWIN) estimates the rate constant for the atmospheric, gas-phase reaction between photochemically produced hydroxyl radicals and organic chemicals. It also estimates the rate constant for the gas-phase reaction between ozone and olefinic/acetylenic compounds. The rate constants estimated by the program are then used to calculate atmospheric half-lives for organic compounds based upon average atmospheric concentrations of hydroxyl radicals and ozone.

GLP compliance:

no

Reaction with:

ozone

Rate constant:

cm³ molecule-1 s-1

Reaction with:

OH radicals

Rate constant:

cm³ molecule-1 s-1

Conclusions:

In the atmosphere alkyl-1,3-diaminopropanes are likely to be degraded by reaction with hydroxyl radicals. The half-life in air is calculated using the EPIsuite QSAR using the advised 500000 OH-radicals/cm3

Executive summary:

In the atmosphere alkyl-1,3-diaminopropanes are likely to be degraded by reaction with hydroxyl radicals. Degradation rates for some components were calculated with the Atmospheric Oxidation Programme based on structure activity relationships developed by Atkinson (1987). With a concentration of 500,000 OH-radicals/cm3, degradation half-lives of 2.9 h for dodedecyl-1,3-diaminopropane, 2.8 h for octadecyl-1,3-diaminopropane (overall OH rate constant: 139.977e-12 cm3/molucule sec), and 2.0 and 1.9 h for the cis- and trans-isomer of oleyl-1,3-diaminopropane, respectively, were calculated. For the exposure calculations, a mean value for the saturated amines of 2.8 h is used. Because there are no important releases into the atmosphere and volatilisation is expected to be negligible, this removal mechanism is thought to be of low relevance.

Description of key information

The substance under evaluation (R814M) is the salt from tallow-1 ,3 -diaminopropane and a mixture of acetate, 2 -ethylhexanoate and tallate. The vapour pressure of salts is in general extremely low and there will therefore not be present as salt in air. The salt will however under environmental conditions mainly be dissociated and the environmental fate and effects will therefore be similar to that of tallow-1,3 -diaminopropane.

Degradation rate constants and half-lifes have been calculated with AOP for various alkyl-1,3-diaminopropanes. The averaged  values calculated for the octadecyl and tetradecyl-1,3-diaminopropanes have been used as key value.  

Key value for chemical safety assessment

Half-life in air:

2.8 h

Degradation rate constant with OH radicals:

0 cm³ molecule-1 s-1

Additional information

In the atmosphere alkyl-1,3-diaminopropanes are likely to be degraded by reaction with hydroxyl radicals. Degradation rates for some components were calculated with the Atmospheric Oxidation Programme based on structure activity relationships developed by Atkinson (1987). With a concentration of 500,000 OH-radicals/cm3, degradation half-lives of 2.9 h for tetradecyl-1,3-diaminopropane, 2.8 h for octadecyl-1,3-diaminopropane, and 2.0 and 1.9 h for the cis- and trans-isomer of oleyl-1,3-diaminopropane, respectively, were calculated. For the exposure calculations, a mean value for the saturated amines of 2.8 h is used. Because there are no important releases into the atmosphere and volatilisation is expected to be negligible, this removal mechanism is thought to be of low relevance.

Direct photolysis of alkyl-1,3-diaminopropanes in air will not occur, because it does not absorb UV radiation above 290 nm .Photo transformation in air is therefore assumed to be negligible.