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.

中文翻译：

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苯甲酸的环境光降解。

药品和个人护理产品是新兴的环境污染物。对于许多这类化合物，包括常见的非甾体类抗炎药甲芬那酸，在地表水中，光解预计将是主要的损失过程。观察到的甲芬那酸的直接光解太阳量子产率为1.5 +/- 0.3x10（-4）。在Suwanee河黄腐酸和密西西比河水以及模型中的光敏化合物3'-甲氧基苯乙酮，2-乙酰基萘酮和吗啉萘酮中均观察到了显着的光敏性。淬火，鼓泡和滤光实验表明，甲芬那酸与受激三重态溶解有机物的直接反应是主要的光敏过程。模型光敏剂的持久性表明，通过三重态能量转移或电子转移，接着敏化剂的快速再生，发生了皮萘醌的光敏作用。由于其量子产率低，预计日光照射的天然水中甲芬那酸的损失取决于直接和间接的光降解过程。