[Electronic Shiazo waterpipes: a new source of indoor air pollutants]. / Elektrische Shiazo-Wasserpfeifen: eine neue Quelle für Innenraumluftschadstoffe.

BACKGROUND: For some time, a new form of waterpipe smoking has been advertised, where steam stones moistened with aroma fluids (Shiazo) are heated electronically. Since there is no combustion of tobacco, it is often assumed that the produced vapor is not harmful to health. To clarify this issue, we performed a comprehensive inner and outer exposure assessment during the use of an electronic Shiazo waterpipe. METHODS: Three volunteers smoked an electronic waterpipe operated with nicotine-free Shiazo stones in a thoroughly ventilated room for 2 h. In three smoking sessions, three fluids with different flavorings were vaporized. In parallel, emissions of particles, volatile organic compounds, polycyclic aromatic hydrocarbons (PAH), and metals were measured in indoor air. Within a biomonitoring study, urinary metabolite profiles of air pollutants were checked. For comparison, the components of the Shiazo fluids were also analyzed. RESULTS: During the smoking sessions, concentrations of formaldehyde, acetaldehyde, glycerine, and propylene glycol rose significantly in the indoor environment. The content of putative carcinogenic PAH in indoor air increased by 42% to 174 ng/m3. Particle number concentrations ranged from 39,968 to 65,610 particles/cm3 (median), with peaks at diameters from 25 to 31 nm. 3­HPMA, the mercapturic acid metabolite of the pyrolysis product acrolein, was strongly elevated in urine samples of the smokers. All fluids contained high amounts of contact allergens. CONCLUSIONS: Electronic Shiazo waterpipes release various harmful substances that considerably impact indoor air quality. Compared to conventional waterpipes, the release of pollutants is lower. Nevertheless, smoking with Shiazo waterpipes is a source of health risks for both users and bystanders.

Towards the Nanosheet-Based Photonic Nose: Vapor Recognition and Trace Water Sensing with Antimony Phosphate Thin Film Devices.

A 2D nanosheet-based photonic nose for vapor identification is presented. A HSbP2 O8 nanosheet thin-film sensor with resistive readout is developed for the tracking of trace amounts of water, and a photonic HSbP2 O8 /TiO2 multilayer structure is effective at optically distinguishing between chemically similar solvent vapors through analyte-specific host-guest interactions.

Touchless Optical Finger Motion Tracking Based on 2D Nanosheets with Giant Moisture Responsiveness.

A new optical touchless positioning interface based on ultrasensitive humidity responsive 1D photonic crystals utilizing the giant moisture dependent swelling capacity of 2D phosphatoantimonate nanosheets is presented. The spatially confined, full spectral color change combined with reversible transparency switching induced by the humidity sheath of a human finger allows for real time, true color lateral finger motion tracking under touchless conditions.

Use of electronic cigarettes (e-cigarettes) impairs indoor air quality and increases FeNO levels of e-cigarette consumers.

Despite the recent popularity of e-cigarettes, to date only limited data is available on their safety for both users and secondhand smokers. The present study reports a comprehensive inner and outer exposure assessment of e-cigarette emissions in terms of particulate matter (PM), particle number concentrations (PNC), volatile organic compounds (VOC), polycyclic aromatic hydrocarbons (PAH), carbonyls, and metals. In six vaping sessions nine volunteers consumed e-cigarettes with and without nicotine in a thoroughly ventilated room for two hours. We analyzed the levels of e-cigarette pollutants in indoor air and monitored effects on FeNO release and urinary metabolite profile of the subjects. For comparison, the components of the e-cigarette solutions (liquids) were additionally analyzed. During the vaping sessions substantial amounts of 1,2-propanediol, glycerine and nicotine were found in the gas-phase, as well as high concentrations of PM2.5 (mean 197 µg/m(3)). The concentration of putative carcinogenic PAH in indoor air increased by 20% to 147 ng/m(3), and aluminum showed a 2.4-fold increase. PNC ranged from 48,620 to 88,386 particles/cm(3) (median), with peaks at diameters 24-36 nm. FeNO increased in 7 of 9 individuals. The nicotine content of the liquids varied and was 1.2-fold higher than claimed by the manufacturer. Our data confirm that e-cigarettes are not emission-free and their pollutants could be of health concern for users and secondhand smokers. In particular, ultrafine particles formed from supersaturated 1,2-propanediol vapor can be deposited in the lung, and aerosolized nicotine seems capable of increasing the release of the inflammatory signaling molecule NO upon inhalation. In view of consumer safety, e-cigarettes and nicotine liquids should be officially regulated and labeled with appropriate warnings of potential health effects, particularly of toxicity risk in children.