Are We Ever Really Alone?

We each have our own personal “bubble” that follows us with particles in every step we take.  Yasemin Saplakoglu, a staff writer with Live Science explains exactly what this means.

There are microbes, chemicals, fungi, microscopic animals and other biological pieces that constantly move around us and form what is called an exposome.  This is actually everything we are exposed to in the moment.  A personal bubble census was conducted using a small air-monitoring device.  The finding was that one person’s exposome could be very different from another’s, even if they are living close to each other.  Their findings were reported online in the journal Cell.

Two things influence our human health and they are our DNA and the environment.  According to Michael Snyder, professor and chair of genetics at Stanford University, people have measured things like air pollution on a broad scale, however no one has measured biological and chemical exposures at a personal level.  It is unknown how vast the human exposome is or what kinds of things are in there.

They recruited 15 participants to wear a small device that was strapped to their arm.  It was worn by some for a month, some a week and Snyder himself wore it for two years.  This device acted like a vacuum and trapped particles directly from a person’s surrounding.  As they all traveled around, the device captured data from over 66 different locations.

The DNA and RNA from the captured particles were analyzed and chemical profiling completed to identify what sorts of microbial and fungal guests they had been hosting.  A data base of over 40,000 species was created to cover the environmental exposures found.  They captured moments that the participants spent with pets, around household chemicals and walking near flowers.

Over 2,500 different species were found surrounding the participants.  Four of the participants wore the device for a month with each person living in different regions of the San Francisco Bay area.  High levels of sludge bacteria was recorded by one participant which is typically found in wastewater or sewage treatment.  Another had final particles which they suspected could be due to the use of an environmentally friendly paint in the house.  This lacks a certain substance that combats fungi.

Snyder had the most data among the participants as he wore the device for two years and recorded traces of his pet exposures and of eucalyptus trees, as examples.

They did find sometimes our personal bubbles are occupied by similar particles, such as traces of DEET, an insect repellant and some carcinogens, such as diethylene glycol.

Even though the device picked up disease causing microbes, it is difficult to differentiate between the dangerous ones and similar ones that aren’t harmful.  The device measures individual instances of exposure for carcinogens, but not absolute levels that they have been exposed through across their lifetime.

Snyder wants to understand how all these little invisible particles can influence our health and hopes to simplify the device so everyone can be out there measuring their own personal exposures.  Perhaps something like an exposome-detecting smartwatch!


Dr Fredda Branyon