Unattached radon progeny as an experimental tool for dosimetry of nanoaerosols: Proposed method and research strategy

Abstract

In this paper the authors discuss a method using 1-nm particulate radon decay products as an experimental tool in the study of local lung deposition and dosimetry for nanoaerosols. The study of aerosol exposure and dosimetry measurements, and related quantitative assessment of health effects, are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry--nanotechnology. Quantitative assessment of aerosol particle behavior in air, in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decades of study. Direct nanoparticle dose measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. The issue of the safe use of radon progeny in such measurements is discussed. One of the properties of radon progeny is that they consist partly of 1-nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols.

Influence of particle size on regional lung deposition – What evidence is there?

“…More recently, Ruzer and Apte discussed the difficulties related to available experimental techniques for assessment of local deposition of nanoparticles (i.e. particles ranging from 1 to 100 nm) in humans (Ruzer and Apte, 2010). The authors then go on to propose a potential method to be used for this purpose based on the unattached fraction of radon progeny.…”

Permeation of Nanoparticles into Pulmonary Surfactant Monolayer: In Situ X-ray Standing Wave Studies

“…NPs bypass the digestive system that allows to avoid losses in the gastrointestinal tract and therefore to reduce significantly the therapeutic dose, compared to oral administration. , High absorption rate is another well-known advantage of NP inhalation, which offers additional pharmaceutical benefits for the development of novel drug delivery methods . Despite the undoubted advantages of nanoaerosolized drugs, their practical application in medicine is limited by their biological adverse effects and dosimetry problems …”

“…7 Despite the undoubted advantages of nanoaerosolized drugs, their practical application in medicine is limited by their biological adverse effects 8 and dosimetry problems. 9 The pulmonary adsorption and biodistribution of NPs are strongly dependent on their physicochemical parameters: particle size and morphology, chemical composition of the particle core, surface reactivity, particle charge, degree of agglomeration, etc. 10 An important factor, governing translocation of NPs across the lung alveoli barrier, is the primary contact with pulmonary surfactant, that covers the inner walls of alveoli.…”

Non‐invasive monitoring of the relation between building materials and indoor radon pollution

“…The radioactivity of natural elements in the building materials makes a notable contribution to the equivalent dose related to a natural radiation background. In [16], gas radon exhalations are proposed to evaluate the concrete condition, whereas in [17], its pervasiveness in the lungs is deployed as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols.…”