Air quality and health hazard of domestic Biomass Burning heating appliances: the experiment at the EUPHORE Chamber

Biomass burning (BB) represents a global concern due to its impact on air pollution, health and climate change, resulting in 2.3 million premature deaths yearly. BB in the residential sector is one of the main sources of primary Particulate Matter emissions. BB emits a significant amount of black and brown carbon, Polycyclic Aromatic Hydrocarbons, and contributes to secondary formation of ozone by photochemical reaction of volatile organic compounds and nitrogen oxides. On the other side, BB is a green and renewable alternative source to fossil fuels reducing carbon dioxide emissions with lower costs, whose use is even expanded due to the last energy crisis and natural gas cost, increasing its impact on both rural and urban areas.

Significantly, BB emission factors (EFs) are affected by a wide range of uncertainties, in terms of primary and secondary air pollutants contribution and in term of health impact estimates. Comprehensive chemical characterization of primary and secondary emissions, combined with the understanding of its potential health effects, requires dedicated experiments to assess a proper offset of BB.

During the MIND-BB campaign primary gaseous and particulate BB emissions from domestic heating devices were sampled and measured within the outdoor EUPHORE chamber, monitoring chemical and physical properties. EUPHORE, sited at CEAM (Valencia-ES), is highly instrumentalized and adapted to introduce fumes from domestic stoves. Given its large size and thanks to its Teflon® FEP cover and to the possibility of opening and closing its sun barrier, the facility can simulate near-real conditions, under both sunlight and night situations. EUPHORE allowed the analysis as well as the aging of the primary emissions. In parallel, we exposed A549 lung epithelial cells cultured at the air-liquid-interface (ALI) to the primary and secondary emissions to evaluate their toxicological hazard mimicking human exposure conditions. Two types of stoves, fuelled with pellet or wood-logs, were tested, and the latter with two different types of wood: Pine and Oak. Measures were performed on primary emissions and aged compounds for each type of fuel (certified pellet, pine, oak), under different conditions (daylight and night) and operation phases (flaming, smouldering). Moreover, for the first time in an outdoor simulation chamber, we performed the direct ALI exposure of human lung cells to primary and aged emissions to define their toxicological hazard providing new and unavailable data.

The results of this integrated innovative methodology will produce a trans-disciplinary improvement in understanding the impacts of BB primary vs secondary emissions on air pollution and its toxicological hazard. These findings will allow to enhance the estimates of emission inventories and scenarios, and to offset the pros and cons of using woody biomass as energy source and its effects on air quality, climate change and health.

Acknowledgments:

This work is part of a project supported by the EC under the Horizon 2020–R&I FP through the ATMO-ACCESS Integrating Activity under GA N.101008004, and by the R+D project ATMOBE (PID2022-142366OB-I00), funded by MCIN/AEI/10.13039/501100011033/ and the "ERDF A way of making Europe” and EVER project CIPROM/20200/37.

We also thank Tatiana Gómez and M.Luisa Martinez for their work on the experiments