2-(2-butoxyethoxy)ethyl methacrylate

Phototransformation in air

Link to relevant study record(s)

Reference

Endpoint:

phototransformation in air

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Principles of method if other than guideline:

calculated using EpiSuite 4.1 (US EPA, 2008)

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
OH
- Concentration of OH radicals: 500000 molecules/cm³
- OH rate constant: 53.3323E-12 cm³/molecule*sec
Ozone
- Concentration of ozone: 7E11 mol/cm³
- Ozone rate constant: 1.1375E-17 cm³/molecule*sec

- Computer program: SRC AOP v1.92
- Other: assuming a 24-hour day

Details on test conditions:

Sensitiser (for indirect photolysis): OH, ozone

DT50:

7.22 h

Test condition:

reaction with hydroxyl radicals assuming a 24 h day at 0.5E6 OH/cm³

DT50:

24.179 h

Test condition:

reaction with ozone assuming a 24 h day at 7E11 mol/cm³

AOP Program (v1.92) Results:

===========================

SMILES : CCCCOCCOCCOC(=O)C(C)=C

CHEM  :

MOL FOR: C12 H22 O4

MOL WT : 230.31

------------------- SUMMARY (AOP v1.92): HYDROXYL RADICALS (25 deg C) --------

Hydrogen Abstraction      = 35.3423 E-12 cm3/molecule-sec

Reaction with N, S and -OH =  0.0000 E-12 cm3/molecule-sec

Addition to Triple Bonds  =  0.0000 E-12 cm3/molecule-sec

Addition to Olefinic Bonds = 17.9900 E-12 cm3/molecule-sec

Addition to Aromatic Rings =  0.0000 E-12 cm3/molecule-sec

Addition to Fused Rings   =  0.0000 E-12 cm3/molecule-sec

 

  OVERALL OH Rate Constant = 53.3323 E-12 cm3/molecule-sec

  HALF-LIFE =    0.301 Days (24-hr day; 0.5E6 OH/cm3)

  HALF-LIFE =    7.220 Hrs

------------------- SUMMARY (AOP v1.91): OZONE REACTION (25 deg C) -----------

  OVERALL OZONE Rate Constant =    1.137500 E-17 cm3/molecule-sec

  HALF-LIFE =     1.007 Days (at 7E11 mol/cm3)

  HALF-LIFE =    24.179 Hrs

 

Experimental Database: NO Structure Matches

Fraction sorbed to airborne particulates (phi):

 0.000544 (Junge-Pankow, Mackay avg)

 0.00733 (Koa method)

    Note: the sorbed fraction may be resistant to atmospheric oxidation 

Conclusions:

Using a valid estimation model the calculated atmospheric half-life (AOP v. 1.92) was approx. 7.2 hour(s). Butyldiglycol methacrylate may
volatilize to air but, due to high reactivity, residual levels of Butyldiglycol methacrylate are expected to be very low.

Executive summary:

Using a valid estimation model the calculated atmospheric half-life (AOP v. 1.92) was approx. 7.2 hour(s) (reaction with hydroxyl radicals assuming a 24 h day at 0.5E6 OH/cm³) and 24.2 hours (reaction with ozone assuming at 7E11 mol/cm³) respectively.

Butyldiglycol methacrylate may volatilize to air but, due to high reactivity, residual levels of Butyldiglycol methacrylate are expected to be very low.

Description of key information

After evaporation or exposure to the air, the substances will be rapidly degraded by photochemical processes.

Key value for chemical safety assessment

Half-life in air:

7.2 h

Degradation rate constant with OH radicals:

0 cm³ molecule-1 s-1

Additional information

The half-life for the reaction of OH radicals with the test substance Butyldiglycol methacrylate is calculated as 7.2 hours assuming a 24h-day (0.5E6 OH/cm³). For the reaction with ozone a half-life of 24.179 h (1.007 d) is calculated (7E11 mol/cm³).

Thus, after evaporation or exposure to the air, the substance will be rapidly degraded by photochemical processes.