Characterization of the exposure to particles emitted from biomass burning systems in indoor environments

The paper deals with the evaluation of the exposure to particles emitted from wood‐burning systems used in homes for heating purposes. In fact, the combustion phenomena involved in such devices are recognized to emit several pollutants both in gas and particle phases. Even though the outdoor emissions of residential heating are regulated in most of the developed countries, no attention was paid to the emission in the indoor environments where people are exposed to long‐lasting high concentrations. Amongst the pollutants emitted during the wood combustion, airborne particles represent a main issue due to both their high emission factors and the high fraction of Benzo[a]pyrene they carries. In fact, B[a]p and airborne particles are considered as carcinogenic compound Group 1 by the IARC, therefore, the cancer risk of people exposed to such aerosols may be tremendously high. In the present research, several homes sited in the Central Italy ﴾Cassino, FR﴿ were tested in terms of indoor airborne particle and B[a]p concentrations during the heating period in order to quantify the contribution of indoor wood‐burning system emissions to the overall particle daily dose received by people. To this end, particle number and mass distributions and total concentrations were measured continuously for several days in each home under investigation. Outdoor particle number and mass concentrations were also measured in order to calculate the possible contribution of particles infiltrating from outdoor. B[a]p concentrations were simultaneously measured. Moreover, questionnaires were filled out by the owners to take note of possible stove/fireplace door openings. Typical daily particle exposures and doses were evaluated for people living in such homes. Moreover, the lung cancer risk of airborne particles was evaluated using an ad‐hoc model able to take into account the contribution of the sub‐ micrometric particles too.