Dioxin is a very potent carcinogen and endocrine disrupter. Scientists say it is exceeded in toxicity only by radioactive waste ( US East Coast Ash for radioactive wood ash). Dioxin is one of the deadly dozen air pollutants. It is a repeat offender and keeps getting recycled in the environment for years. It lasts in the human body for seven years. For example go see pictures of Victor Yushchenko who was recently poisoned by dioxin. His face is now ravaged.
Wood burning is the third largest source of dioxin in the United States.
Slide Show (20 slides) by Dr. Bruce D. Rodan, National Center for Environmental Assessment, Office of Research and Development, US EPA, Washington DC. Polychlorinated Dioxins and Furans: Sources, Emissions, and Levels. Nov. 1997
In the San Francisco Bay Area residential wood burning is the second largest source, and accounts for as much dioxin as 100 factories and industrial sites, including landfills, incinerators, foundries, cement kilns, coke ovens and hazardous waste furnaces. San Francisco wood burning is estimated to produce 0.424 grams of dioxin per year and is the second largest source (Meltzer, Lawrence Livermore national Lab 2001 Report). Compare to nonspecific source fires at 0.097 grams of dioxin per year, or hazardous waste incineration at Shell and Chevron of 0.063 grams of dioxin (California Air Resources Board, 1999).
Dioxins, byproducts of combustion processes rise high into the atmosphere as smoke particles, fall to the earth in rain, lodge in the soil and water, and coat water and land plants. The plants are eaten by animals and by humans. Humans eat food such as milk and meat, which comes from animals, which eat contaminated plants and water. Dioxins are deadly and are recycled over and over again in the environment. They are reported to contaminate virtually our entire food supply.
"Burning 1 kilogram of wood produced as much as 160
micrograms of total dioxins. This result was obtained when various
specimens of wood were burned in different stoves. Soot was collected
and analyzed by well-designed and documented procedures. Tetrachlorinated,
hexachlorinated, heptachlorinated, octachlorinated dioxins were
present. The isomers of the dioxins were separated and quantified.
The highly chlorinated dioxins were the major components. In the
soot from a series of experiments, their total content ranged
from 10 to 167 mg/kg of fuel. The total yields of tetrachlorinated
dioxins (TCDDs) ranged from 0.1 to 7.8 mg/kg of fuel."
[Science, Vol. 266 Oct. 21, 1994,T.J. Nestrick and L.L. Lamparski, Anal. Chem. 54, 2292 (1982)].
Dioxin Handout a 1 page handout.
PCBs (polychlorinated biphenyls) Emissions from residential fireplace and woodstove appliances burning fuels available from the San Francisco Bay area were sampled for polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HxCBz), particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs, and the monosaccharide levoglucosan. A total of 32 PAH compounds, ranging in concentration from 0.06 to 7 mg/kg, amounted to between 0.12 and 0.38% of the PM mass, depending on the wood and facility type.[Gullett, B. K.; Touati, A.; Hays, M. D., PCDD/F, PCB, HxCBz, PAH, and PM Emission Factors for Fireplace and Woodstove Combustion in the San Francisco Bay Region, Environ. Sci. Technol.; (Article); 2003; 37(9); 1758-1765.]