Pulmonary and cardiovascular responses of rats to inhalation of a commercial antimicrobial spray containing titanium dioxide nanoparticles

Abstract

Our laboratory has previously demonstrated that application of an antimicrobial spray product containing titanium dioxide (TiO 2 ) generates an aerosol of titanium dioxide in the breathing zone of the applicator. The present report describes the design of an automated spray system and the characterization of the aerosol delivered to a whole body inhalation chamber. This system produced stable airborne levels of TiO 2 particles with a median count size diameter of 110 nm. Rats were exposed to 314 mg/m 3 min (low dose), 826 mg/m 3 min (medium dose), and 3638 mg/m 3 min (high dose) of TiO 2 under the following conditions: 2.62 mg/m 3 for 2 h, 1.72 mg/m 3 4 h/day for 2 days, and 3.79 mg/m 3 4 h/day for 4 days, respectively. Pulmonary (breathing rate, specific airway resistance, inflammation, and lung damage) and cardiovascular (the responsiveness of the tail artery to constrictor or dilatory agents) endpoints were monitored 24 h post-exposure. No significant pulmonary or cardiovascular changes were noted at low and middle dose levels. However, the high dose caused significant increases in breathing rate, pulmonary inflammation, and lung cell injury. Results suggest that occasional consumer use of this antimicrobial spray product should not be a hazard. However, extended exposure of workers routinely applying this product to surfaces should be avoided. During application, care should be taken to minimize exposure by working under well ventilated conditions and by employing respiratory protection as needed. It would be prudent to avoid exposure to children or those with pre-existing respiratory disease.

Effect of titanium dioxide nanoparticles on the cardiovascular system after oral administration

“…Kan et al (2014) demonstrated that pulmonary inhalation of ultrafine titanium dioxide (UF TiO 2 ) significantly increased heart rate and elevated mean and diastolic blood pressure in response to norepinephrine (Kan et al, 2014). McKinney et al (2012) also found rats inhaled a commercial antimicrobial spray containing TiO 2 NPs could induce significant pulmonary and cardiovascular responses. Our previous study showed that tracheal instillation of TiO 2 NPs induced considerable systemic inflammation, endothelial dysfunction and lipid metabolism dysfunction, contributing to the progression of atherosclerosis in ApoE knockout mice .…”

Comparative modeling of exposure to airborne nanoparticles released by consumer spray products

“…In the highest dose, exposure resulted in increased respiratory rate, pneumonia and lung cell damage. However, exposures in this dose range are not expected for consumers (McKinney et al, 2012). Other studies found varying contents of NPs in sprays.…”

“…In the aerosol, liquid droplets in the nanometer range and NPs were found. The investigated spray was also tested on rats in a subsequent study of the same group (McKinney et al, 2012). In the highest dose, exposure resulted in increased respiratory rate, pneumonia and lung cell damage.…”

Zinc oxide nanoparticle-induced atherosclerotic alterations in vitro and in vivo

“…3,4 Inhalation of NPs is associated with pulmonary and cardiovascular responses. 5,6 Inhaled nanoparticles can readily deposit in lung tissue and induce inflammatory response in lung alveoli. 7,8 Translocation of inhaled nanoparticles into the systemic circulation has been detected and might be related to adverse cardiovascular effects.…”