2009 patent publication date. When the chlorine dioxide concentration was 0.07 ppm, there was about 60% reduction (45/71) in the enzyme activity"

2017. ****!!!!**** Chlorine Dioxide in Air tested on rats, with no significant damage. Personal air disinfectant of chlorine dioxide (gel?) had high virucidal activity against influenza virus; when CD was used at low, low-toxic concentrations, the virus titer in the air samples was reduced by 90% at 1–3 min, by 97% at 3–5 min, and by 99% at 10–12 min. Device was effective at least 30 days. The inhalation toxicity of CD was investigated in the experiments using the rats that were kept in an atmosphere of CD for a certain time. Then the structure of the trachea and lungs examined; the degree of oxidative stress was estimated from the tissue level of malonic aldehyde and the changes in the gene expression of all classes of antioxidant enzymes (a total of 15). The structure of the tracheal and lung epithelium was ascertained to be completely preserved; there were no increases in apoptotic cell death in both tissues or in lipid peroxidation in lung tissue. The enhanced protection of tracheal and lung epithelial cells against the highly toxic reactive oxygen species generated in the tissues is associated with the activation of gene expression of antioxidant enzymes in the epithelium, which is observed within the first hours after action of CDFull text (partially translated) at https://medi.ru/info/13658/

***Mentions use of Chlorine Dioxide in Air in Occupied Areas to combat respiratory infections.

2010. This study aims to monitor bioaerosol levels of a local campus of a student health center in Taiwan and then to perform disinfection by applying chlorine dioxide. First, air samples were taken and evaluated in the six areas of the center. The average background bioaerosol levels were 714 +/- 1706 CF …

******!!!!****!!!!****!!!*** 2012. {Note: Click "Download full text" and wait. Full text file will download to your computer} "More than half of the ClO2 gas decomposed indoors." Gaseous ClO2 is chemically dissociated by light with wavelengths between 350 nm and 475 nm. They reported that the dominant (96%) dissociation products were ClO and O (atomic oxygen). It is important to take into account whether these dissociation products are toxic to humans. Judging from the short lifetime of O (39 ns), the toxic effect of this chemical, if ever present, would be negligible... High air temperatures and light irradiation accelerated the decrease of ClO2 gas concentration; the latter had the greatest influence. A quicker decay of concentration and greater value of the reaction rate constant of ClO2 were found under irradiated conditions, especially when a UV lamp was used... ClO2 gas concentration was significantly reduced when an evaporative humidifier was employed due to adsorption and a chemical reaction between the gas and the filter in the humidifier. The results obtained from these experiments can be used to predict the indoor concentration of ClO2 gas" "it was concluded that indoor humidity does not affect the reaction of the ClO2 gas" "an aquarium... filled with 10 L(2.64 gal) water was set in the room" "indoor ClO2 gas levels were lower in the room where water was present because the gas dissolved in water" "Ogata and Shibata (2008) reported that ****!! ClO2 gas concentration in virus aerosols is theoretically 0.12 µM when the aerosols are in equilibrium with 0.03 ppm ClO2 gas !!****, based on their revealed Henry’s equilibrium gas constant k = 3.9 × 10−5 mol 1−1 Pa−1. The present experiment showed higher concentrations of ClO2 in the water"

****!!!!!***** Using a methodology that can maintain low chlorine dioxide concentration in air even under high humidity, examined the effect of humidity on airborne influenza virus inactivation at a very low gas concentration. It was shown that chlorine dioxide at less than 0.02-0.03 ppm has an ability to inactivate airborne influenza virus under 50% and 70% RH conditions. However, from a viewpoint of infection control, these researchers believed it is a minor effect which is merely additional to the major effect by the humidity itself, when considering the actual load of viruses released from an influenza patient in a room space and still active after certain time. Low concentrations of chlorine dioxide also make much less difference under 30% relative humidity levels common in winter." Original paper https://www.semanticscholar.org/paper/Inactivation-of-Airborne-Influenza-Virus-Using-Low-Nishimura-Hayashi/3cc74aad740dc6e036e76a3e4fdaee02a159a309 https://pdfs.semanticscholar.org/3cc7/4aad740dc6e036e76a3e4fdaee02a159a309.pdf

****2020. China. Therefore, the safe disinfection based on chlorine dioxide is eligible to become the core means of active disinfection and epidemic prevention system for schools and kindergartens.

** Air concentrations for odor control. Restoration-chemicals.com (China?) {Solid chlorine dioxide for long-term use in HVAC ventilation. Air pump to expedite vapor treatments.}