A walk in the park - identifying healthy biomes using scent snapshots

1.O_LIBiogenic volatile organic compounds (bVOCs) emitted by plants can promote stress reduction and cognitive benefits, whereas anthropogenic VOCs (aVOCs) common in urban air, such as BTEX compounds, pose health risks. We aimed to characterise and compare these airborne chemicals across urban greenspaces and develop a novel, health-oriented metric for site evaluation. C_LIO_LIAir samples were collected across six Oxford greenspaces on a single date using Tenax filters and analysed by GC-MS. Data were processed using metabolomics-style workflows, identifying 245 biologically relevant compounds. Multivariate analyses compared site profiles, and one site was monitored over 12 months to assess environmental influences. C_LIO_LIGreenspaces exhibited significantly different volatile signatures, including variation in both health-promoting bVOCs and harmful aVOCs. Temperature, humidity, wind speed, and rainfall significantly influenced the presence and abundance of beneficial compounds. C_LIO_LIThese results highlight the importance of considering airborne chemistry in urban planning and public health decision-making. Integrating VOC profiling into planning and public health strategies could support delivery of higher-quality, health-promoting urban environments and inform guidance on optimal timing for outdoor activity. C_LI Societal Impact StatementAs urbanisation accelerates globally, access to nature is increasingly recognised as vital for public health and wellbeing. We captured and analysed plant-emitted airborne "scent signatures" across Oxfords urban greenspaces to assess their potential health relevance. We found that sites differ in levels of health-promoting volatiles and harmful pollutants, and that these compounds vary with environmental conditions such as temperature and humidity. Our findings provide a novel framework for evaluating urban greenspaces, informing planning, air-quality management, and public health strategies to create greener, healthier cities.