An interdisciplinary approach for air quality assessment: biomonitoring using Tillandsia bergeri and risk perceptions in the environmentally sacrificed province of Chacabuco, Chile.

Awareness of air pollution and the associated environmental and health risks is growing worldwide. In order to answer the socio-environmental challenges posed by climate change, natural resource degradation and industrialization, scientists are advocating more holistic research linking environmental quality and public health. However, few studies have managed to integrate local communities' concerns and knowledge with easy-to-use biomonitoring systems to produce science that contextualises their environment risk. This case study was carried out in an "environmental sacrifice zone" located in the Chacabuco province (Chile), where there have been no prior air quality studies or monitoring despite local populations suspecting metallic contamination. An interdisciplinary approach was proposed to create an innovative air quality assessment, combining both social and geographical data for risk perception and biomonitoring experiments with epiphyte plants (T. bergeri) in strategic sites. The cross-analysis of inhabitant interviews and cognitive maps shows that air pollution is perceived to be of greater risk in the northern and central part of the province. Microscopic and spectroscopic techniques highlight different origins of metal(loid)s in the air. Epiphyte plants reveal a site-dependent accumulation of pollutants (As, Cu, Cr, Mn, Pb, Ni, Zn). The collection of dust in Owen gauges and subsequent health risk assessment do not show evidence of hazard quotient or cancer risk. But enrichment factors and pollution indexes highlight that three sites can be classified as impacted, suggesting that more attention should be paid to chronic exposure and long-term environmental effects in this area. The social perception of air pollution appears to be correlated to the geochemical identification of some existing sources of metal(loid)s.