The biologic degradation of 2,2-bis(4-hydroxyphenyl)propane (bisphenol A [BPA]; 1) was studied with 26 fungi. An initial BPA concentration of 40 ppm in an aqueous solution was degraded in the dark for 14 d. Among the 26 strains tested, 11 degraded BPA at 50% or more. Furthermore, four strains (F. sporotrichioides NFRI-1012, F. moniliforme 2-2, A. terreus MT-13, and E. nidulans MT-98) were more effective for degradation of BPA.

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The voltammetric reduction behavior o f ozone in an acidic solution was examined at gold, platinum, glassy carbon, and graphite reinforcement carbon (GRC) electrodes. The GRC electrode, the lead of a mechanical pencil, exhibited a well-defined ozone reduction wave at 0.8-0.9 V versus a saturated calomel electrode (SCE) on a flat base current, whereas gold and glassy carbon electrodes were insensitive or nonselective t o ozone. The platinum electrode showed no base current and, hence, made background correction difficult. The response was not degraded by long exposures o f the GRC electrode t o the ozonized solution. The reduction of ozone at the GRC electrode was controlled by a sluaish charge-transfer step and diffusion. Differential pulse voltammetric peak current showed a linear variation with ozone concentration up t o the detection limit of 6 X lo-' mol/dm3 ozone in acidic solutions. Residual ozone in tap water disinfected by chlorine was determined by the present method; a linear calibration curve was also obtained.Ozone has been used as a chemical disinfectant for water or waste water treatment. Analysis of residual ozone for the water treatment involves iodometric oxidation and ultraviolet absorbance [ 11. These methods are facile, but they are often subject t o interference from most o f oxidants and organic compounds. Because the iodometric method depends on solution conditions and requires mixing and titration processes, it is not suitable for continuous automatic monitoring. Practical analysis of ozone is expected to have selectivity, speed, and applicability to in situ measurements with continuous automatic control.Amperometric detection is promising for these requirements. Smart et al. [ Z ] good voltammetric performance a s good as that exhibited by precious metal electrodes. Because lead from a mechanical pencil (not ordinary pencils) can be used as the GRC electrode, it holds promise as a disposable electrode. In this article, the amperometric monitoring of ozone by a GRC electrode is studied with regard to its selectivity, durability, and reproducibility. EXPEULMEN7XiGold and platinum wires and a glassy carbon rod were coated with epoxy resin, and their electrode surfaces were exposed in disk form by polishing the hardened blocks. The GKC rod, Uni-HB (Mitsubishi Pencil Ltd.), 0.5 0 19% VCH Publishers. Inc

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