Impact of Environmental Microparticles on Insect Olfaction

Terrestrial insects underpin key ecosystem services, including pollination, herbivory regulation, decomposition, nutrient cycling, and disease control. These functions depend on chemical communication that guides insects to food, mates, hosts, shelters, and oviposition sites while helping them avoid threats. Environmental microparticles, such as micro- and nanoplastics, tyre wear particles, soot, mineral dust, and agricultural residues, are now widespread across air, soil, vegetation, and indoor environments, exposing insects through contact, deposition, and ingestion. Growing evidence shows that these particles disrupt insect olfaction by adsorbing volatile compounds, blocking antennal sensilla, and interfering with receptor and neuronal processes. These disruptions impair foraging, mating, oviposition, and host seeking, leading to reduced individual performance and declines in population density. As a result, insect-mediated services such as pollination, biological control, seed dispersal, and nutrient cycling are weakened, with consequences for plant community composition, biodiversity, food web stability, and crop yields. Despite these advances, the mechanisms linking microparticles to olfactory disruption remain poorly resolved, and no synthesis has integrated evidence across the full pathway from signal emission to neural processing. This review brings together chemical, physiological, and ecological evidence to map how microparticles interfere with insect olfaction across this pathway, identify key knowledge gaps, and propose a multi-level research framework to guide future work from molecular mechanisms to ecological consequences.