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A bench-scale study of the degradation of four selected pharmaceuticals and personalcare products (PPCPs) was carried out using ultraviolet (UV) and UV/Hsub2/subOsub2/sub treatment employing lowpressure (LP) and medium pressure (MP) lamps. The target substances included thepharmaceutical compounds ibuprofen, naproxen, and gemfibrozil, along with thebactericide triclosan. The main objectives for the portion of the study reported in thispaper were: to compare removals in ultra-pure water to results using partially treatedwater from a drinking water treatment plant; to determine the influence of water qualityparameters on treatment efficacy; and, to estimate the kinetic parameters associated withthe degradation of the selected compounds.Target compounds were spiked together into ultra-pure and pretreated water at levels(500-1000 ng/L) fairly close to the ones reported in the aquatic environment. The resultsfor the LP lamp showed minimal, if any, removals with 40 mJ/cmsup2/sup irradiation. At thesame fluence, the addition of 10 mg/L Hsub2/subOsub2/sub resulted in removals as high as 66%. Lowerremovals observed with one of the partially-treated waters may be attributed to higheralkalinity, although further investigation is required.In contrast, the MP lamp led to measurable degradation of all four compounds even at alow fluence of 40 mJ/cmsup2/sup. The highest removals observed were for triclosan, which hasbeen shown to be susceptible to photolysis. The benefits of adding Hsub2/subOsub2/sub whenemploying a MP lamp were not seen until the highest fluence (300 mJ/cmsup2/sup) was applied,at which point removals were especially enhanced for ibuprofen and gemfibrozil whencompared to UV alone. It is possible that the lower fluences were insufficient to producea sufficient concentration of hydroxyl radicals to have an effect, under the matrixconditions. Overall, the removals in partially-treated water were lower than in ultra-purewater. Includes 18 references, figures.

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Edition: Vol. - No. Published: 11/01/2006 Number of Pages: 12File Size: 1 file , 400 KB