How genotoxic is the indoor air environment?

Abstract

The indoor environment changes based on a variety of different factors, therefore changing the genotoxic potential of that environment. Despite the associations of exposure to outdoor air pollution and links to health impacts, enough is not currently known about the impacts to human health indoor air may have. Due to the variable nature of the indoor environment (multiple things can change this environment, including but not limited to, the use, occupants, materials within the environment, animals, the outside environment and ventilation) this can prove difficult. Indoor particulate matter (PM) of various sizes (PM2.5-PM10 for example) has been shown to induce reactive oxygen species, increase markers in oxidative stress, double strand DNA breaks, and cause 8-oxoguanine lesions in both in vitro and in vivo models (including humans). The particle type and source influence these responses, highlighting heating and cooking fuel sources that may be more genotoxic than others. A similar pattern has also been observed with volatile organic compounds (VOCs) with various mixtures of VOCs and different VOC compositions inducing DNA damage differently, with diet also being a contributing factor to genotoxic potential. A significant knowledge gap in the potential genotoxicity of indoor air pollution is the exposure of various biologicals found indoors. Moulds, other fungi, and allergens are an emerging health risk and are of significant public interest. Little is known about the inhalation toxicology and mechanisms of action of these components, and this is becoming increasing important to understand due to public deaths linked to them. There is overlap with the health effects of outdoor air pollution where there has been much more research focus. Therefore, the aim of this review is to establish what is already known, the potential limitations of the current work and where we should focus research in the future.