The identity, diversity, and abundance of distinct types of bioaerosol particles, as well as their temporal and spatial variability, are not well characterized. Bioaerosols play a key role in the dispersal of reproductive units from plants and microbes (pollen, spores, etc.), for which the atmosphere enables transport over geographic barriers and long distances (Fröhlich-Nowoisky et al. 2016). The dispersal of plant, animal, and human pathogens and allergens has major implications for agriculture and public health.
Our research determined that airborne microbes can reach the upper atmosphere (above the boundary layer, ~2 km altitude) and deliver disease into downwind destinations. We partnered with NASA Ames to utilize a unique set of bioaerosol samples from NASA atmospheric aircraft observatories in the upper troposphere and lower stratosphere to study the microbial diversity, abundance, and viability of bioaerosols reaching California during the spring season, when the jet stream delivers the largest amount of Asian transpacific aerosols to North America. We analyzed the aerosol samples using microbiological techniques, shotgun metagenomic sequencing, and advanced bioinformatic tools to identify the viable and total microbial species detected. A number of bacterial and fungal species were identified. This study provided a deeper understanding of the microbial species that can survive in the upper atmospheric conditions. We also assessed the bioaerosol transport and potential impact to humans using meteorological and atmospheric dispersion computer models and demonstrated that exposure extends throughout North America. We created a foundation for future studies to better understand the potential impact of airborne microbes on disease transmission affecting human, animal, or crop health.
This research aligns with Lawrence Livermore National Laboratory's biosecurity and atmospheric science mission areas and enriches the Laboratory's core competency in biosciences and bioengineering. The project advances the Laboratory's productive relationship with NASA Ames and supports NASA's aerobiology and astrobiology research priorities. Research outcomes benefit mission areas, such as aerosol transport and disease transmission, espoused by the Department of Health Services, Department of Defense, and the National Institutes of Health.
Fröhlich-Nowoisky, J., et al. 2016. "Bioaerosols in the Earth system: Climate, health, and ecosystem interactions." Atmospheric Research 182 (Supplement C):346–376. doi: 10.1016/j.atmosres.2016.07.018.
Smith, D., et al. 2018. "Airborne Bacteria in Earth's Lower Stratosphere Resemble Taxa Detected in the Troposphere: Results From a New NASA Aircraft Bioaerosol Collector (ABC)." Frontiers in Microbiology 9 (1752). doi: 10.3389/fmicb.2018.01752. LLNL-JRNL-756269.
Urbaniak, C., et al. 2018. "Detection of Antimicrobial Resistance Genes Associated with the International Space Station Environmental Surfaces." Scientific Reports 8. doi: 10.1038/s41598-017-18506-4. LLNL-JRNL-736498.
Lawrence Livermore National Laboratory • 7000 East Avenue • Livermore, CA 94550
Operated by Lawrence Livermore National Security, LLC, for the Department of Energy's National Nuclear Security Administration.