Werner Jeffrey J, McNeill Kristopher, Arnold William A
Water Resources Science Program, University of Minnesota, 1985 Buford Avenue, St. Paul, MN 55108, USA.
Chemosphere. 2005 Mar;58(10):1339-46. doi: 10.1016/j.chemosphere.2004.10.004.
Pharmaceuticals and personal care products are an emerging class of environmental pollutants. Photolysis is expected to be a major loss process for many of these compounds in surface waters, including the common non-steroidal anti-inflammatory drug mefenamic acid. The direct photolysis solar quantum yield of mefenamic acid was observed to be 1.5+/-0.3x10(-4). Significant photosensitization was observed in solutions of Suwanee River fulvic acid and Mississippi River water, as well as for the model photosensitization compounds 3'-methoxyacetophenone, 2-acetonaphthone and perinaphthenone. Quenching, sparging and light-filtering experiments suggested a direct reaction of mefenamic acid with excited triplet-state dissolved organic matter as the major photosensitization process. The persistence of the model photosensitizer suggests that the photosensitization by perinaphthenone occurs either by triplet-energy transfer or an electron transfer followed by rapid regeneration of the sensitizer. Due to its low quantum yield, the loss of mefenamic acid in sunlit natural waters is expected to depend on both direct and indirect photodegradation processes.
药品和个人护理产品是一类新出现的环境污染物。光解作用预计是地表水中许多此类化合物的主要损失过程，包括常见的非甾体抗炎药甲芬那酸。观察到甲芬那酸的直接光解太阳量子产率为1.5±0.3×10⁻⁴。在萨凡纳河富里酸和密西西比河水溶液中，以及对于模型光敏化化合物3'-甲氧基苯乙酮、2-乙酰萘和苊醌，均观察到显著的光敏化现象。猝灭、鼓泡和滤光实验表明，甲芬那酸与激发三重态溶解有机物的直接反应是主要的光敏化过程。模型光敏剂的持久性表明，苊醌的光敏化作用要么通过三重态能量转移发生，要么通过电子转移随后敏化剂快速再生发生。由于其量子产率较低，预计在阳光照射的天然水中甲芬那酸的损失将取决于直接和间接光降解过程。
