Hi Stovers; I was at a lecture a couple of months ago given by Dr. Paul Connett (St. Lawrence University, NY) on the environmental risks of gasification of municipal solid waste. One of the things he mentioned was the heath risks of nano particles. He said that they can be small enough to cross the blood-brain barrier and accumulate in the brain. I searched the Web of Science to see if this kind of pollution was being measured with cookstoves, and found the following:
Hosgood, HD; Lan, Q ; Vermeulen, R; Wei, H; Reiss, B; Coble, J; Wei, FS; Jun, X; Wu, GP; Rothman, N (2012) Combustion-derived nanoparticle exposure and household solid fuel use in Xuanwei and Fuyuan, China. International Journal Of Environmental Health Research 22: 571-581 DOI: 10.1080/09603123.2012.684147 Abstract: Combustion-derived nanoparticles (CDNPs) have not been readably measurable until recently. We conducted a pilot study to determine CDNP levels during solid fuel burning. The aggregate surface area of CDNP (mu m(2)/cm(3)) was monitored continuously in 15 Chinese homes using varying fuel types (i.e. bituminous coal, anthracite coal, wood) and stove types (i.e. portable stoves, stoves with chimneys, firepits). Information on fuel burning activities was collected and PM2.5 levels were measured. Substantial exposure differences were observed during solid fuel burning (mean: 228.1 mu m(2)/cm(3)) compared to times without combustion (mean: 14.0 mu m(2)/cm(3)). The observed levels during burning were reduced by about four-fold in homes with a chimney (mean: 92.1 mu m(2)/cm(3); n = 9), and effects were present for all fuel types. Each home's CDNP measurement was only moderately correlated with the respective PM2.5 measurements (r(2) = 0.43; p = 0.11). Our results indicate that household coal and wood burning contributes to indoor nanoparticle levels, which are not fully reflected in PM2.5 measurements. There is an erratum for this article that corrects the authorship H. Dean Hosgood, Roel Vermeulen, Hu Wei, Boris Reiss, Joseph Coble, Fusheng Wei, Xu Jun, Guoping Wu, Nat Rothman and Qing Lan This paper is about CDNP released from stoves, but it does briefly review research on toxicology: • there is evidence that toxicity increases with decreasing particle size • the ultrafine size fraction has been found to induce the greater levels of inflammation and oxidative damage than it’s larger counterparts. • it has been suggested that due to their small diameter, nanoparticles are capable of penetrating epithelial cells, entering the bloodstream from the lungs • animal studies have shown pro-inflammatory effects after inhalation exposure; proinflammatory gene transcription has been observed as a result of oxidative stress associated with CDNP (Shukla et al. 2000); carbon nanoparticles have been found to exacerbate airway inflammation and alter cytokine expression; CDNP induction of cellular reactive oxygen species (ROS) production and toxic oxidative stress. For TLUDs, I think we should be concerned about polynuclear aromatic hydrocarbons and dioxins in these nanoparticles. It may be that TLUD emissions are infinitely preferable to 3-stone emissions, but where possible, I would suggest that cookstoves have some sort of chimney. Regards, Julien -- Julien Winter Cobourg, ON, CANADA _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://stoves.bioenergylists.org/
