DETERMINATION OF PENTAMIDINE ISETHIONATE IN AIR

A concern currently exists regarding the potential for exposure of hea lth care workers to pentamidine isethionate, a drug used for preventio n and treatment of Pneumocystis carinii pneumonia in immunocompromised patients, including those with human immunodeficiency virus infection . In order to evaluate worker exposures, a sampling and analytical met hod for pentamidine isethionate in air has been developed. This method involves sampling with a 37-mm PVC membrane filter at 1 to 2 L/min, r ecovery with 3 mL of 50:50 ethanol:water with 0.085% phosphoric acid a nd 0.04% tetramethylammonium chloride in an ultrasonic bath for 10 min , and analysis by high performance liquid chromatography with fluoresc ence detection. The limit of detection is about 18 ng per sample, and the lower limit of quantitation is 50 ng per sample. Recoveries of pen tamidine isethionate from PVC filters were 0.76 to 0.91 at 50 to 8820- ng levels of fortification. Samples were stable on PVC filters during 27 days of storage at room temperature. Because patients who are treat ed with pentamidine isethionate are at increased risk of contracting t uberculosis (TB), safety precautions for handling samples contaminated with TB were included in the sampling and analytical method.