Leaching behavior and the estrogenic activity of phthalate monoesters

市售的牙科软聚合物含有各种类型的邻苯二甲酸酯作为增塑剂。据报道，邻苯二甲酸酯具有雌激素活性。本研究的目的是研究牙科软质聚合物中邻苯二甲酸酯在不同浸泡介质中的浸出行为。邻苯二甲酸酯的连续浸泡时间为14天。浸泡在乙醇溶液中的软聚合物的邻苯二甲酸酯浸出量大于浸泡在蒸馏水中的邻苯二甲酸酯。实验中的软聚合物(基于三种类型的邻苯二甲酸酯)也观察到了类似的浸出行为。另外，对实验的软聚合物在浸泡在人唾液中的情况下进行了额外的实验，以考察口腔内条件下的淋洗行为。浸泡在人唾液中的邻苯二甲酸酯与浸泡在蒸馏水中的邻苯二甲酸酯的淋洗模式不同。实验中的软聚合物在浸泡在人类唾液中时，比浸入水中的聚合物渗出更少的邻苯二甲酸酯。这一发现可能是由于人类唾液中的各种酶对邻苯二甲酸酯的水解。

The commercially-available dental soft polymers contain various types of phthalate esters as plasticizer. Phthalate esters reportedly have estrogenic activity. The purpose of this study was to investigate the leaching behavior of phthalate esters from dental soft polymers under various immersing mediums. The phthalate esters showed continuous leaching for 14-days immersion. The amount of leached phthalate esters from the soft polymers immersed in ethanol solution was greater than that immersed in distilled water. The similar leaching behavior was observed for the experimental soft polymers (based on three types of phthalate esters). Additional experiment was carried out for the experimental soft polymers under immersed in human saliva to examine the leaching behavior under intra-oral conditions. The leaching of phthalate esters immersed in human saliva showed a different pattern from immersed in distilled water. The experimental soft polymers leached less amount phthalate esters when immersed in human saliva than those immersed in water. This findings would be due to the hydrolysis of phthalate esters by various enzymes in human saliva.