A novel passive sampler for long-term monitoring of isocyanates in air

Isocyanates are known as widespread hazardous environmental pollutants emitted from various combustion products in our lives because they cause health effects to the nervous system and respiratory systems through sensitization. In this study, to obtain data on the concentration and composition of isocyanates in indoor and outdoor air, we developed a novel passive sampler (PSG-DBA) for monitoring gaseous and particulate isocyanates; e.g. isocyanic acid (ICA), methyl isocyanate (MIC), ethyl isocyanate (EIC), and propyl isocyanate (PIC), and acquired basic data of isocyanates on the behavior in general households. This proposed method allows for continuous sampling over a week, making it possible to calculate not only intermittent data but also low concentrations and average concentrations of isocyanate in our daily lives. In addition, from the results of this monitoring, in particular, ICA and MIC were frequently detected in ambient air. In summer, indoor concentrations were typically higher than those outdoors in most houses, e.g., mean concentrations; ICA; 0.21 ppb (summer), 011 ppb (winter); MIC; 0.0052 ppb (summer), 0.0038 ppb (winter). These were also affected by temperature fluctuations due to climate change during summer. PSG-DBA can monitor a wide range of environments to further investigate the environmental dynamics of isocyanates in the future.