Based on epidemiological studies, exposure to indoor air pollutants such as volatile organic compounds (VOCs) during fetal and early postnatal life may be associated with health problems including abnormal development, decreased lung growth, increased rate of respiratory tract infections, childhood asthma, behavioral problems, and neuro-cognitive detriments. Plastic materials are a major contributor to VOCs found indoors. Incubators used to house premature infants in the neonatal intensive care unit (NICU) are made of plastic. Recently, VOC emissions inside of neonatal incubators were found to increase when temperature and humidity were increased to simulate clinically relevant settings. Many pieces of medical equipment commonly used in the care of preterm neonates that are derived from plastic as well as synthetic or laundered bedding materials capable of contributing VOCs to the incubator environment. Therefore, the purpose of this study was to determine whether routinely used plastic medical equipment and bedding produce VOCs not previously identified and/or higher levels of previously identified VOCs.
· All air samples were collected using 6-liter laboratory-evacuated electro-polished stainless steel air sampling canisters (Restek, Bellefonte, PA, USA).
· Four timed air samples were collected from each of four Ohio Care Plus incubators with and without the plastic medical equipment/bedding at during different operational settings. (Table 1)
· Ambient air samples were collected at four collection times.
- Samples and analysis were based on EPA TO-15 “Determination of Volatile Organic Compounds in Air Collected in specialty prepared Canisters and analyzed by Gas Chromatography/Mass Spectrometry (GS/MS)”.
Table 1: Incubator Air Sampling Schedule
Sample Collection #
Incubator State: Operational Settings & Equipment/Bedding Present
28° / Mattress only
28° / Mattress / Additional Medical Equipment*
37° / Mattress / Additional Medical Equipment*
37° / 50% Humidity / Mattress / Additional Medical Equipment*
*IV tubing, NG tube, Blanket, CPAP prongs , O2 tubing, B/P cuff, Diaper, Pacifier, Sheepskin, Cardio-pulmonary leads w/adhesive backing
- Analyses of the incubator air samples collected identified the presence of several VOCs.
- Cyclohexanone was common to all incubator air samples following the addition of plastic medical equipment/bedding and was not identified in the ambient air samples.
- The concentration of cyclohexanone increased with the higher temperature and humidity (see Figure 1).
- This study identified and quantitated the presence of cyclohexanone in all incubator air samples containing plastic medical equipment and bedding items.
- The concentration of this VOC increased when incubators were exposed to increased temperature and humidity.
- Studies have reported uptake, metabolism and excretion of inhaled cyclohexanone in humans.
- Cyclohexanone inhalation toxicity results in sensory irritation and acute neurotoxicity in adults.
- More studies are needed to evaluate the effects of cyclohexanone exposure during the neonatal period.