Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Photodegradation was estimated using version 1.92 of the Atmospheric Oxidation Program for Microsoft Windows (AOPWIN) that estimates the rate constant for the atmospheric, gas-phase reaction between photochemically produced hydroxyl radicals and organic chemicals. The half-life (22.19 hours) indicates that after evaporation or exposure to the atmosphere, the substance will be rapidly degraded by photochemical processes.

Based on a hydrolysis study in buffered solutions, hydrolysis will only contribute to degradation in alkaline waters at pH 8 and above (Dow Chemical Company, 1997). Hydrolysis is not the predominant degradation process since the test substance is readily biodegradable. Therefore, hydrolysis will not contribute significantly to the degradation of HPA under environmental conditions.