Indoor Air Pollution by Methylsiloxane in Household and Automobile Settings

Abstract

This study examines characteristics of atmospheric methylsiloxane pollution in indoor settings where interior renovation/redecoration is being undertaken, in addition to ordinary family homes and inside family cars. Concentrations of atmospheric methylsiloxane in these locations were approximately one order of magnitude higher than that in outdoor areas. The average indoor concentration of methylsiloxane where renovation was being undertaken was 9.4 μg/m3, which is slightly higher than that in an ordinary family home (7.88 μg/m3), while samples from family cars showed lower concentration (3.10 μg/m3). The indoor atmospheric concentration during renovation/redecoration work was significantly positively correlated with the duration of the work. The structure of atmospheric methylsiloxane pollution is basically the same in these three venues. The concentration of annulus siloxane was much higher than that of linear compounds (85% of the total methylsiloxane concentrations). Household dust in average family homes showed total methylsiloxane concentration of 9.5 μg/m3 (average); the structure mainly consisted of linear siloxane (approximately 98% of total concentration), thereby differing from that of atmospheric methylsiloxane pollution. The comparatively high concentration of methylsiloxane in these three venues indicates that interior renovation and decoration work, and even travelling in cars, can involve exposure to more serious siloxane contamination during everyday activities.

Silica: ubiquitous poison of metal oxide interfaces

“…Volatile organic silicon compounds (VOSCs) are widely used in consumer goods such as electronics, furniture, healthcare, pharmaceuticals, cosmetics, and cookware, 93 leading to significantly higher concentrations indoors than outdoors. [94][95][96] Over the last decades, a great deal of effort has been invested in identifying Si-impurity sources and developing means for avoiding contamination. For example, van Berkel et al prevented Si-poisoning in oxygen permeation membrane measurements by avoiding VOSC containing grease in the manual valves of the experimental setup.…”

Study of Indoor Ventilation Based on Large-Scale DNS by a Domain Decomposition Method

“…The Heating, Ventilation and Air Conditioning (HVAC) system has become the primary mechanism for maintaining the acceptable indoor air quality in modern buildings. Thus, the proper design of HVAC systems is strongly connected to physical health [1][2][3][4][5]. However, one problem associated with HVAC systems is that, in a typical working environment involving the emission of gases or dust, it is necessary to select a high enough ventilation flow rate to remove the generated air contaminants such as PM 2.5 [6][7][8].…”

“…An indoor ventilation model. The reconstructed room model comes from the study of J. D. Posner, C. R. Buchanan, D. Dunn-Rankin*[3], the model has a floor area of 91.4cm×45.7cm with a height of 30.5cm and a 15.25cm high partition is built in the middle of the room to separate the two Zones. The horizontal cross-section area of ventilation inlet and ventilation outlet are both 10cm×10cm, and the height of both inlet and outlet ventilation ducts are 0.020m.…”

MIL-101(Cr) MOF as an Effective Siloxane Sensor

“…The degradation mechanism breaks the polymer into smaller chains, producing linear (L) or cyclic (D) volatile methylsiloxane (VMS) byproducts such as hexamethyldisiloxane (L2) or octamethylcyclotetrasiloxane (D4) . Depending on the contamination source and environmental conditions, the resulting airborne siloxane concentration is highly variable, ranging from several ng m –3 (<1 ppb) in the case of outdoor sources to multiple mg m –3 (100 s of ppm) for contaminated enclosed spaces. ,− In terms of environmental impact, although they are generally regarded as nontoxic and inert, VMSs are classified as substances of high concern by the European Union REACH Regulation due to their persistent and bioaccumulative nature . More importantly, VMSs at levels of μg m –3 (0.01–10 ppm) cause serious concerns for nearby sensitive apparatus in enclosed environments.…”