ISOCYANATES IN MEDICAL DEVICES AND PRODUCTS: A QUALITATIVE ASSESSMENT

Purpose: It is hypothesized that direct contact of newborn infants with medical devices and products that have polyurethane and polyurethane foam components will result in skin exposure to isocyanates and subsequent immune response or sensitization. This sensitization may lead to asthma later in their lives. This study was conducted to qualitatively evaluate residual isocyanate content on medical devices and products used in a neonatal intensive care unit (NICU), as the initial step to assess neonatal infants' isocyanate skin exposures. Methods: Thirty-seven commonly used medical devices and products were selected and qualitatively tested. Test items were laid on the laboratory bench. Aromatic and aliphatic isocyanate Surface SWYPE" pads were used with 5 drops of acetone on the pads to wipe the surfaces of tested items using three fingers and moderate pressure; then the pads were placed on them with close contact. After 3 minutes, 60 minutes, and 24 hours the pads and medical devices were observed for an orange to red color change that indicates the presence of a specific type of isocyanate. Result was rated as positive if a color change was observed within 24 hours and negative if no color change occurred. Results: Twenty-seven percent (10 of 37) medical devices and products tested showed a color change, either on the wipe pad or/and on the product surfaces indicating the presence of either/or both free and bound isocyanate functional groups. Most colors indicated aromatic isocyanates except for one medical device, the z-flo fluidized positioned cushion that indicated aliphatic isocyanates. Conclusions: This study demonstrated that some medical devices and products used in NICU setting contain polyurethane or polyurethane foam components. Further studies to evaluate additional devices and products qualitatively are needed. These medical devices and products that were identified as containing isocyanates have been further tested to identify and quantify isocyanate species. The results are presented in a companion abstract. The potential transfer of isocyanates onto the surfaces of neonatal infants also needs to be assessed.