Risk of Second-Hand Exposure to Aerosol Pentamidine

The objective of this study was to assess the dispersion of pentamidine from a busy aerosol pentamidine (AP) clinic providing 38 AP treatments per day to various locations in an ambulatory medical facility. Patients self-administered 60 mg of AP using Fisoneb (ultrasonic nebulizer) in treatment rooms with doors closed. All treatment rooms had high volume air filtration units equipped with high efficiency particle air (HEPA) filters installed. Exhaust air from the AP clinic and especially the treatment rooms were directed by special ventducts away from the general recirculation system of the building. Ambient air samples were collected from multiple sites of the building to assess the extent of AP spillover. Pentamidine levels were measured by high pressure liquid chromatography (HPLC). The highest level of pentamidine was found in the treatment room at 0.01645 mg/m³. A lower level was detected in the waiting room area of the clinic at 0.01282 mg/m³. Only fractions of those levels were found at the other sites. Based on these ambient levels, the health risk implications of long-term exposure to low dose AP was estimated to be negligible.