Mechanisms of lung toxicity induced by biomass burning aerosols

Abstract

Background: Carbonaceous aerosols emitted from indoor and outdoor biomass burning are major risk factors contributing to the global burden of disease. Wood tar aerosols, namely, tar ball particles, compose a substantial fraction of carbonaceous emissions, especially from biomass smoldering. However, their health-related impacts and toxicity are still not well known. This study investigated the toxicity of the water-soluble fraction of pyrolyzed wood tar aerosols in exposed mice and lung epithelial cells.Results: Mice exposed to water-soluble wood tar aerosols showed increased inflammatory and oxidative stress responses. Bronchial epithelial cells exposed to the same water-soluble wood tar aerosols showed increased cell death with apoptotic characteristics. Alterations in oxidative status, including changes in reactive oxygen species (ROS) levels and reductions in the expression of antioxidant genes related to the transcription factor Nrf2, were observed and were confirmed by increased levels of MDA, a lipid peroxidation adduct. Damage to mitochondria was observed as an early event responsible for the aforementioned changes. Conclusions:The toxicity and health effect-related mechanisms of water-soluble wood tar were investigated for the first time in the context of biomass burning. Wood tar particles may account for major responses such as cell death, oxidative stress, supression of protection mechnaisms and mitochondrial damaged cause by expsoure to biomass burning aerosols.

Toxicity of Water- and Organic-Soluble Wood Tar Fractions from Biomass Burning in Lung Epithelial Cells

“…Wood tar was generated and characterized as previously described. 12 , 15 , 16 , 19 Briefly, pinewood pellets (Hallingdal Trepellets; water content 6.55 wt %; length 2–3 cm, diameter 0.2–0.3 cm) were pyrolyzed at 550 °C, and the distilled tar materials were collected using a water-cooled trap. The water-soluble fraction of the tar materials was extracted with Milli-Q water (18.2 MΩ, sterilized by UVC irradiation) and filtered using 0.45 and 0.2 μm syringe filters in sequence (polytetrafluoroethylene [PTFE] membrane, Pall Corporation, MA, US) to remove impurities and particulates.…”

“… 1 , 4 , 5 , 9 The observed adverse health effects were often associated with respiratory symptoms (such as asthma and chronic obstructive pulmonary disease, COPD), cardiovascular disease, 4 , 17 cancer, 17 and mortality. 4 The mechanisms by which biomass burning aerosols cause adverse health effects involve oxidative stress, inflammation, 18 , 19 and genotoxic and epigenetic changes. 20 , 21 The adverse health effects of aerosols from biomass burning are associated with physicochemical properties such as size, surface area, and chemical composition 6 , 8 , 17 and may vary with different combustion conditions and the distance from the fire source.…”

Polar semivolatile organic compounds in biomass-burning emissions and their chemical transformations during aging in an oxidation flow reactor

“…Biomass burning (BB), including both wildfires and prescribed burns, is a major source of carbonaceous aerosols in the atmosphere (Penner et al, 1991) and can contribute up to 75 % of total atmospheric aerosol mass loading (Andreae and Merlet, 2001;Park et al, 2007). These carbonaceous aerosols have a significant impact on both regional and global radiative forcing (Ramanathan and Carmichael, 2008).…”

“…These carbonaceous aerosols have a significant impact on both regional and global radiative forcing (Ramanathan and Carmichael, 2008). BB emissions also can cause adverse health effects (Arbex et al, 2007;Regalado et al, 2006) because of the toxicological properties of particle-bound organic compounds (Chen et al, 2017;Pardo et al, 2020;Pavagadhi et al, 2013;Sigsgaard et al, 2015;Yang et al, 2010). Therefore, the comprehensive, molecular-level characterization of BB emissions is essential for understanding health effects.…”

Application of Natural Carbon Isotopes for Emission Source Apportionment of Carbonaceous Particulate Matter in Urban Atmosphere: A Case Study from Krakow, Southern Poland

“…This is due to growing public awareness of the impact of air quality on human health. There are a number of studies presenting the negative impact of air pollution on human health [1][2][3]. Krakow is one of the Polish cities affected by poor air quality, and at the same time, it is a pioneering city in Poland undertaking diverse actions to improve it.…”