Bacteria can travel thousands of kilometers in dust: study

Bacteria that can affect humans and animals can cross oceans and continents via airborne dust, according to a new Israeli study.

In a study published last month in the Journal of Geophysical Research: Biogeosciences, authors Daniella Gat, Ralf Zimmermann, and Yinon Rudich analyzed airborne dust collected in Rehovot, Israel. They used DNA sequencing to learn about the bacteria found in the dust and used trajectory modeling to determine that the dust came from places such as North Africa, Saudi Arabia and Syria.

What they found was that when the wind lifted the dust off the ground, the attached bacteria moved with it. When the dust settles again in a new location, the attached bacteria can alter the environmental chemistry and affect human and animal health.

“Changing climates are expected to increase the intensity and frequency of dust storms, expanding the geographic range of airborne bacteria,” the authors write. So is the ocean. ”

Researchers still don’t know exactly how these bacteria affect the environments they land on, but the study says they can look for clues to the origins of the bacteria. , bacteria in airborne dust can come from soil, water bodies, plants, landfills, livestock farms, and other sources.

“Different bacterial functions are relevant to these different environments,” the study said.

“Thus, by examining the functional genes of airborne bacteria and comparing them to the surrounding environment, we can gain knowledge about possible sources of airborne bacteria and their potential function during deposition. .”

By better understanding the genes of these bacteria, scientists may be able to find other clues about the impact these bacteria have on the environment.

For example, when the authors examined the genes of dust-carrying bacteria, they found that some bacteria were more likely to be antibiotic-resistant than those found in seawater, plant surfaces, or in soil. rice field.

The spread of antibiotic-resistant bacteria can have potential health implications for humans, livestock, plants, and ecosystems, the authors write, but if the bacteria are still alive and reach their final destination, the authors write. It depends on whether they can reproduce when they reach .

“Since there is still little knowledge about the role of the aerobiome in Earth’s ecosystems, it is difficult to estimate how changes in its composition affect environmental function,” the authors write.

“It is therefore essential to continue efforts to describe, record and analyze aerobiome composition, functional profiles, survival rates and activity.”