Table 1 Summary of the main findings

Overall ecosystem surveys are possible through air sampling and are not limited by preselection of specific domains of life.

Rapid extraction, shotgun sequencing and cloud-based analysis of air eDNA are feasible with current technologies.

Spatiotemporal diversity changes can be observed from shotgun eDNA, consistent with expectations.

Air eDNA had even higher proportions of eukaryotic and metazoan DNA than water or sediment samples, indicating that shotgun airborne DNA is particularly suited to analysis of animal species.

Simultaneous pathogen, invasive species, endangered species, pest species, disease-vector species, narcotic (biological) and allergen surveillance are possible from air eDNA shotgun sequencing, with agricultural, biodiversity, wildlife conservation, health and economic applications.

Identifying the population of origin of a species is possible from air eDNA alone. Population genetics could be performed even from air in wild complex community settings. This can be achieved either by long-read sequencing (for example, air capture of intact full-length mitochondrial reads) or by short-read sequencing.

The results obtained by either ONT long-read or Illumina short-read shotgun sequencing of air eDNA showed generally good alignment, indicating that either method captures the underlying diversity within a sample.

Shotgun sequencing of eDNA (air, water and sediment) can be used to screen for AMR genes. Similarly, other genetic variants could be screened for within eDNA shotgun sequencing data, such as insecticide or pesticide resistance markers.

Reads that passed quality filters but that did not align to any known database entries (not analysed here), are probably rich in novel previously unrecorded genetic diversity, possibly including reads from species not previously sequenced. De novo assembly approaches could reveal the hidden diversity within them.

Hybridization-based enrichment of air eDNA from complex settings is effective, enabling more cost-effective and targeted eDNA analyses, for example, for variants of concern, population genetics, targeted species, resistance markers and so on.

The human-related shotgun sequencing, human exome enrichment and human qPCR from airborne DNA capture suggest the feasibility of advanced air eDNA forensics applications.