Acute health effects from exposure to indoor ultrafine particles—A randomized controlled crossover study among young mild asthmatics

Abstract

Particulate matter is linked to adverse health effects, however, little is known about health effects of particles emitted from typical indoor sources. We examined acute health effects of short‐term exposure to emissions from cooking and candles among asthmatics. In a randomized controlled double‐blinded crossover study, 36 young non‐smoking asthmatics attended three exposure sessions lasting 5 h: (a) air mixed with emissions from cooking (fine particle mass concentration): (PM2.5: 96.1 μg/m3), (b) air mixed with emissions from candles (PM2.5: 89.8 μg/m3), and c) clean filtered air (PM2.5: 5.8 μg/m3). Health effects (spirometry, fractional exhaled Nitric Oxide [FeNO], nasal volume and self‐reported symptoms) were evaluated before exposure start, then 5 and 24 h after. During exposures volatile organic compounds (VOCs), particle size distributions, number concentrations and optical properties were measured. Generally, no statistically significant changes were observed in spirometry, FeNO, or nasal volume comparing cooking and candle exposures to clean air. In males, nasal volume and FeNO decreased after exposure to cooking and candles, respectively. Participants reported additional and more pronounced symptoms during exposure to cooking and candles compared to clean air. The results indicate that emissions from cooking and candles exert mild inflammation in asthmatic males and decrease comfort among asthmatic males and females.

Characterization of residual debris on packaged hip arthroplasty stems demonstrates the dominance of less than 10 μm sized particulate: Updated USP788 guidelines for orthopedic implants

“…It is also important to note that residual surface‐bound implant particulate is not continually released in vivo but, as a worst case, can be assumed to be a one‐time bolus dose. Further comparison of exposure level of residual implant particle criteria to everyday exposure (i.e., <1 × 10 7 particles for <1 μm sized residual particles) indicates that it is approximately equivalent to the amount of 0.1 μm sized particles inhaled in 10 average breaths of good quality outdoor air in rural conditions (i.e., 1.3 × 10 6 particles per breath: 0.1 μm particles: 2610 × 10 6 particles/m 3 in good quality rural air, at 500 mL per average breath) 36–38 …”

“…that it is approximately equivalent to the amount of 0.1 μm sized particles inhaled in 10 average breaths of good quality outdoor air in rural conditions (i.e., 1.3 Â 10 6 particles per breath: 0.1 μm particles: 2610 Â 10 6 particles/m 3 in good quality rural air, at 500 mL per average breath) [36][37][38]. …”

Health impacts of PM2.5 originating from residential wood combustion in four nordic cities

“…According to Vicente et al [ 59 ], this increase is especially high during open fireplace operation where PM 10 concentrations can rise up to twelve times as compared to background concentrations. Moreover, candles are very often used during wintertime in Denmark [ 60 ], and a high concentration of candle induced PM 2.5 has shown a mild inflammatory response among young asthmatics as a result of five hours of exposure [ 61 ]. Nevertheless, it has been discussed that addressing ambient and indoor RWC exposure as separate risk factors can lead to double counting due to their interrelated nature [ 44 ].…”

Airway and systemic biomarkers of health effects after short-term exposure to indoor ultrafine particles from cooking and candles – A randomized controlled double-blind crossover study among mild asthmatic subjects

“…In the published studies on healthy subjects in exposure chambers with candle or cooking emissions, adverse effects on lung function [ 19 ], cardiovascular outcomes including blood pressure, arterial stiffness and heart rate variability [ 20 – 22 ], and brain activity [ 23 , 24 ] have been demonstrated, though no single effect has been observed in all studies. In a previous publication from the present study, we have reported on changes in the nasal mucosa and exhaled nitric oxide (NO)-concentrations, the particle number and volume size distribution as well as the light scattering ability of the particles, and decreasing self-reported well-being following exposure to cooking and candle emissions among subjects with mild asthma [ 25 ]. In observational and intervention studies, indoor exposure to particles in the fine and ultrafine size range has been associated with systemic inflammatory biomarkers such as declining levels of endothelial progenitor cells, oxidative stress, and release of several cellular mediators, such as cytokines [ 26 – 29 ], all of above mechanisms relevant in the causal pathway to cardiovascular and pulmonary disease [ 29 – 31 ].…”

“…The PM properties are discussed in terms of estimated mass distributions and their hygroscopic properties are presented. For the convenience of the reader some description of exposure characteristics already described in [ 25 ] are summarized herein.…”