Registration Dossier
Registration Dossier
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EC number: 203-157-5 | CAS number: 103-90-2
Phototransformation in air
Administrative data
Link to relevant study record(s)
Description of key information
The atmospheric oxidation half-life of Paracetamol was estimated using the AOPWIN model. It was estimated that the substance is not persistent in air medium as the half-life period of Paracetamol in air is only 0.92 days (22.08 hrs.) which is not exceeding the criteria of >2 days. The photo transformation rate is 1.8 x 10-11 cm3/molecule/sec. This indicates that Paracetamol will react at a moderate rate (22.08 hrs.) with hydroxyl radicals. The fraction of the chemical that is sorbed to organic particles in the air may be resistant to atmospheric oxidation.
Key value for chemical safety assessment
- Half-life in air:
- 0.92 d
- Degradation rate constant with OH radicals:
- 0 cm³ molecule-1 s-1
Additional information
The atmospheric oxidation half-life of Paracetamol was estimated using the AOPWIN model. It was estimated that the substance is not persistent in air medium as the half-life period of Paracetamol in air is only 0.92 days (22.08 hrs.) which is not exceeding the criteria of >2 days. The photo transformation rate is 1.8 x 10-11 cm3/molecule/sec. This indicates that Paracetamol will react at a moderate rate (22.08 hrs.) with hydroxyl radicals. The fraction of the chemical that is sorbed to organic particles in the air may be resistant to atmospheric oxidation.
OVERALL OH Rate Constant = 1.8E-11 cm3/molecule-sec.
Media |
Half-Life |
Percent in |
Air |
0.92 days |
0 % |
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