A pentachlorophenol (PCP)-degrading Pseudomonas sp. strain UG30 was encapsulated in kappa-carrageenan for use in PCP degradation. Free and encapsulated cells were compared for their ability to dechlorinate and mineralize 100-800 mu g/ml sodium pentachlorophenate in broth. Dechlorination was measured with a chloride ion electrode, and mineralization was measured by (CO2)-C-14 evolution from radiolabelled [U-C-14]PCP. Free and encapsulated Pseudomonas sp. UG30 cells mineralized up to 200 mu g/ml and 600 mu g/ml PCP, respectively, after 21 days. Encapsulation of UG30 cells provided a protective effect, allowing dechlorination and mineralization of high levels of PCP to occur.