Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Hydrolysis

No test on hydrolysis is available. However, p-cresol is classified as readily biodegradable. Therefore no test is required according to REACH Regulation, Annex VIII, column 2. With regard to its chemical structure hydrolysis is not expected to be a relevant fate process.

Indirect photolysis in the atmosphere

In the atmosphere, p-cresol will react with photochemically produced hydroxyl-radicals. In his critical review Atkinson recommended values for the reaction constant kOH at room temperature of 4.7 x 10-11 cm³ x molecule-per second. Based on a tropospheric OH radical concentration of 5 x 105molecules per cm³ a corresponding half-life of 8.0 h can be calculated.

In an experiment the temperature dependency of the reaction constants in a smog chamber was determined. The calculated half-life is 3.8 h for p-cresol at 23°C.

Indirect photolysis in the hydrosphere

In the hydrosphere the cresols are expected to undergo photolytical degradation because of the presence of the aromatic ring which acts as a chromophore. By irradiation of solutions of p-cresol in a merry-go-round reactor, with rose bengal as a sensitizer, a half-life of 21 d in surface water under noon summer sunlight and the latitude of Switzerland was estimated.