Drexel University, Philadelphia, PA, USA.
University of California, Irvine, CA, USA.
Environ Sci Process Impacts. 2024 Feb 21;26(2):305-322. doi: 10.1039/d3em00399j.
Indoor surfaces are coated with organic films that modulate thermodynamic interactions between the surfaces and room air. Recently published models can simulate film formation and growth gas-surface partitioning, but none have statistically investigated film composition. The Indoor Model of Aerosols, Gases, Emissions, and Surfaces (IMAGES) was used here to simulate ten years of nonreactive film growth upon impervious indoor surfaces within a Monte Carlo procedure representing a sub-set of North American residential buildings. Film composition was resolved into categories reflecting indoor aerosol (gas + particle phases) factors from three sources: outdoor-originating, indoor-emitted, and indoor-generated secondary organic material. In addition to gas-to-film partitioning, particle deposition was modeled as a vector for organics to enter films, and it was responsible for a majority of the film mass after ∼1000 days of growth for the median simulation and is likely the main source of LVOCs within films. Therefore, the organic aerosol factor possessing the most SVOCs contributes most strongly to the composition of early films, but as the film ages, films become more dominated by the factor with the highest particle concentration. Indoor-emitted organics ( from cooking) often constituted at least a plurality of the simulated mass in developed films, but indoor environments are diverse enough that any major organic material source could be the majority contributor to film mass, depending on building characteristics and indoor activities. A sensitivity analysis suggests that rapid film growth is most likely in both newer, more air-tight homes and older homes near primary pollution sources.
室内表面涂有有机膜，这些有机膜调节着表面与室内空气之间的热力学相互作用。最近发表的模型可以模拟膜的形成和生长以及气体-表面分配，但没有一个模型对膜的成分进行了统计学调查。这里使用气溶胶、气体、排放物和表面的室内模型（IMAGES），通过模拟代表北美住宅建筑子集的蒙特卡罗程序，模拟了 10 年内不透气室内表面上无反应性膜的生长。膜成分被分解为三个来源的室内气溶胶（气体+颗粒相）因素的类别：室外起源、室内排放和室内生成的次生有机物质。除了气体到膜的分配外，颗粒沉积被建模为有机物进入膜的载体，并且在模拟的中位数中，它在约 1000 天的生长后负责膜质量的大部分，并且很可能是膜内低挥发性有机化合物的主要来源。因此，具有最多半挥发性有机化合物的有机气溶胶因素对早期膜的组成影响最大，但随着膜的老化，膜越来越受到颗粒浓度最高的因素的主导。室内排放的有机物（来自烹饪）在发育中的膜中通常至少占模拟质量的多数，但室内环境足够多样化，任何主要的有机物质来源都可能是膜质量的主要贡献者，这取决于建筑特征和室内活动。敏感性分析表明，在更新、更密封的房屋和靠近主要污染源的旧房屋中，膜的快速生长最有可能。
