Health effects of residential wood smoke particles: the importance of combustion conditions and physicochemical particle properties

Abstract

Background: Residential wood combustion is now recognized as a major particle source in many developed countries, and the number of studies investigating the negative health effects associated with wood smoke exposure is currently increasing. The combustion appliances in use today provide highly variable combustion conditions resulting in large variations in the physicochemical characteristics of the emitted particles. These differences in physicochemical properties are likely to influence the biological effects induced by the wood smoke particles.

Organic compounds in PM2.5 emitted from fireplace and woodstove combustion of typical Portuguese wood species

“…It should be noted, however, that the dilution ratio used in our study is comparable to the majority of values reported in the literature for biomass burning experiments (Lipsky and Robinson, 2005). The PM 2.5 emission factors for the fireplace and the woodstove are in the range of values reported for identical household combustion appliances in Scandinavia (Bølling et al, 2009; and references therein). However, particle emissions from the woodstove are much higher than those obtained in the "chimney type" stove and in other modern combustion devices (Bølling et al, 2009).…”

“…The PM 2.5 emission factors for the fireplace and the woodstove are in the range of values reported for identical household combustion appliances in Scandinavia (Bølling et al, 2009; and references therein). However, particle emissions from the woodstove are much higher than those obtained in the "chimney type" stove and in other modern combustion devices (Bølling et al, 2009). Thus, it seems that the major differences in emission factors are due to large variations in combustion appliance types.…”

“…Gonçalves et al (2010) reported ratios ranging from 0.9 for maritime pine PM 10 emissions to 4.4 for the smoke of cork oak emitted from the combustion in a "chimney type" stove. Higher OC/EC ratios have been reported for lowtemperature combustion in conventional fireplaces and stoves, confirming that particulate matter from these appliances are dominated by OC (Bølling et al, 2009), while higher EC mass fractions in smoke particles from the combustion of woody biomass in more efficient modern small scale units (modern logwood stoves with secondary air and automated air supply, and pellet stoves) contributed to lower OC/EC ratios, sometimes comparable to those from vehicular emissions. Ratios <1 have been determined at tunnel and roadside sites, where vehicle exhausts were the dominant sources of aerosols (Cheng et al, 2010).…”

“…Burning wood of poor quality (e.g. high moisture content), overloading the firebox or insufficient air supply, are examples of conditions that can lead to incomplete combustion, characterised by low temperature (Bølling et al, 2009). Lipsky and Robinson (2005) tested the effects of dilution on fine particle mass concluding that too little dilution can potentially overestimate the fine particle mass emissions, and too much dilution can underestimate them.…”

Research on the Electrical Capacitance and Electrical Conductivity of Char Resulting From Natural and Treated Wood

“…Hemicellulose decomposes at 200-325 ºC, cellulose -at 220-375 ºC, lignin at 250-500 ºC (Bolling et al 2009;Mahltig et al 2009;Goodrich et al 2010;taghiyari 2011). the results of thermographic research carried out by other authors suggest that, within the decomposition of materials, combustion is affected by both substance (tree) species (Bednarek et al 2009) and the rate of a rise in temperature (Hagen et al 2009;Fulianga et al 2012;Blijderveen et al 2013) as well as by the environment (oxidizing, reducing gas) in which the substance is studied (Jiang et al 2010;Fu et al 2011).…”