Fig. 1.

Dissipation of seven phytotoxins in microcosms using sand filter material from Regnemark waterworks over a period of 14 days (at 10 °C). Mean concentration and standard deviation (error bars) are given as percentage of the initial concentration (C₀, 300 µg L^-1) in biologically active microcosms (duplicates) and abiotic control (single microcosm). Jacobine and senecionine concentrations are given as percentage of the initial concentration of jacobine N-oxide and senecionine N oxide. ‘Biotic’ refers to microcosms with biologically active filter sand and ‘abiotic’ to microcosms with autoclaved filter sand.