Environmentally persistent free radicals in indoor particulate matter, dust, and on surfaces

Abstract

Environmentally persistent free radicals (EPFR) are an emerging class of constituents in particulate matter (PM). They are relatively stable with lifetimes of days to years in the condensed phase, influence...

Partitioning of reactive oxygen species from indoor surfaces to indoor aerosols

“…The inhalation rate, IR, is taken to be 16 m 3 day −1 ; 31 the time spent outdoors (per day), t out , is taken to be 0.07 days; 32 the remaining time is assumed to be spent indoors, t in , is 0.93 days; the body mass, BM, is 70 kg (ref. 31) and n is the number of partition coefficient bins chosen for the simulation (100 in this case). While not explicitly calculated here, inhaled dose of gas-phase OPX can be determined by replacing C p,i in eqn (9) by C g,i .…”

“…Like Khurshid, they found that the indoor and outdoor ROS concentrations in PM2 were nearly identical even though the indoor concentration of outdoor-sourced PM (referenced to aerosol sulfate) was significantly lower than outdoors. Using a magnetic spin-resonance method, Fillipi et al 31 measured environmentally persistent free radicals (EPFR) in total suspended particulate matter in an apartment and at an outdoor monitoring station in Mainz, Germany over a 2 months period (September–November, 2019). The authors observed that their indoor and outdoor values were similar on most days, but not strongly correlated.…”

Chemical Fate of Oils on Indoor Surfaces: Ozonolysis and Peroxidation

“…24,34,78,94 In particular, the persistent organic radicals within the aged film complicate the environmental impacts, because this "reservoir" of indoor reactivity is capable of triggering further oxidation. 86 Similar lipid photooxidation has been reported in human skin lipids after UVA radiation, inducing oxidative stress 95 that contributes to skin diseases. 96,97 The initiation could also be triggered by indoor artificial lighting with emission wavelengths below 400 nm.…”

“…The derived hyperfine splitting parameters agree with those reported in the literature. − Both radical species may originate from the intermediates in the peroxidation mechanism (Figure b) or secondary hydroperoxide decomposition (mechanisms in Figures S8 and S9). Overall, our results are consistent with the recent work by Filippi et al that indicates indoor surfaces are a large source of environmentally persistent free radicals (EPFR) . Such species could significantly impact indoor environments due to their high reactivity.…”

“…Overall, our results are consistent with the recent work by Filippi et al that indicates indoor surfaces are a large source of environmentally persistent free radicals (EPFR). 86 Such species could significantly impact indoor environments due to their high reactivity.…”