US EPA

2648989 

Journal Article 

Exposure to forest fires, radioactivity and health risks 

Carvalho, FP; Oliveira, JM; Malta, M 

2012 

No 

PORTUGUESE SOC OCCUPATIONAL SAFETY & HYGIENE 

GUIMARAES 

126-130 

WOS:000320994300022 

It is known that vegetation fires release particles and a large number of chemical compounds into the atmosphere, including previously deposited radionuclides from the Chernobyl nuclear accident. However, the release of naturally-occurring radionuclides accumulated in vegetation was not investigated before. This work reports results of a study on natural radionuclide concentrations in vegetation including bushes and forest trees, and radionuclides in smoke from vegetation wildfires. Results show high concentrations of alpha emitting radionuclides in smoke particles, especially Po-210, and enrichment of this radionuclide in smoke particles by a factor of 10(2) - 10(3) when compared with 210 Pb. Polonium activity is higher in the smallest particles (<0.50 mu m) of smoke aerosols, while refractory radionuclides such as uranium and thorium displayed low concentrations in this aerosol fraction and higher concentrations in larger particles ( fly ash particles). Especially due to Po-210, the inhalation of smoke from vegetation fires may deliver significant radiation doses to the lung. In a person respiring smoke near a vegetation fire over 24 hours, the radiation dose may be 4000 times higher than the annual dose to a person respiring clean air. Even disregarding the effect of particles and other toxic compounds also present in smoke, the protection of the respiratory tract is needed due to these high Po-210 concentrations in smoke. 

Polonium; uranium; forest fires; radionuclide inhalation; radiation dose to man 

Melo, R; Miguel, AS; Perestrelo, GP; Arezes, P; Baptista, JS; Barroso, MP; Carneiro, P; Cordeiro, P; Costa, N; 

8th International Symposium on Occupational Safety and Hygiene (SHO) 

Guimaraes, PORTUGAL