Impact of Microplastics on Plant Biogenic Volatile Organic Compounds Emission: A Preliminary Study

Abstract

Plants produce biogenic volatile organic compounds (BVOCs) that are essential for communicating their physiological status and interacting with the environment. As emerging pollutants, microplastics (MPs) may influence BVOCs emissions, yet their effects remain poorly underexplored. This study employed headspace solid phase microextraction coupled with gas chromatography – mass spectrum to investigate the impact of MPs on the BVOC emission profiles of lettuce (Lactuca sativa). Our results demonstrated that polystyrene (PS) MPs, even at environmental concentrations (0.5 – 2 mg/L), significantly altered BVOC profiles, with higher MPs concentrations leading to greater deviations from the control group. These changes were linked to oxidative stress pathways, evidenced by reduced superoxide dismutase (SOD) activity and shifts in root microbial communities. The key discriminating BVOCs identified suggest that the presence of MPs impact plant survival and adaptability. These emissions likely originated from various metabolic pathways, including phenylpropanoid, lipoxygenase, and terpenoid synthesis pathways. Furthermore, variations in type, size, and aging treatment of MPs influenced BVOCs emission patterns. Our findings underscore the significance of BVOCs as indicators of exposure risks associated with MPs and highlight the ecological threats posed by these pollutants.

Keywords: Biogenic volatile organic (BVOCs), HS-SPME, Microplastic leachate, Lettuce (Lactuca sativa), Metabolic pathways, Antioxidant System. Microbial community