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Environmental fate & pathways

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2,4,6-tribromophenol was shown to be hydrolytically stable and to photodegrade in air with a half life of 4.6 hours and the half-life for photolysis in water was 11.5 hours.

Studies show that enriched cultures of bacteria from wastewater and in water/sediment systems are capable of biodegrading 2,4,6-tribromophenol through reductive debromination, with transformation to 4-bromophenol. Degradation rates depend in part on temperature and whether these were other food sources present for the bacteria. Rapid (36 hours) degradation of 2,4,6-tribromophenol was observed enriched cultures of bacteria isolated from a marine sediment. It can be reasonably concluded that the test material is inherently biodegradable in both freshwater and marine conditions.

2,4,6-tribromophenol is also rapidly biodegraded in soil under aerobic conditions, with a geometric mean half life of 7 days at 20°C (DT50 5 - 10 days, 3 soils), indicating non-persistence. Mineralisation to carbon dioxide and the formation of bound residues were demonstrated. No single degradation product was greater than 10%.

The values used for the CSA are as follows:

Hydrolysis: hydrolytically stable

Photodegradation half-life: 4.6 h

Photolysis half-life:11 hr

DT50 in soil: 7 d at 20°C

Biodegradability: Inherently biodegradable