- Alicia Hernandez por_puesto
- BBC News World
The fact that people release chemical compounds – when breathing or sweating, for example – has been well known. The fact that we can transform other substances, and thus “clean up” our environment, was not.
This is exactly what a team of scientists from the Mac Planck Institute of Chemistry (Germany) and researchers from the United States and Denmark have discovered: we have an “oxidation domain” that changes the chemistry that surrounds us.
Whether outdoors, in our homes, on transportation, or at work, we are exposed to many chemicals and pollutants. Whether it’s paints, emissions, or even what we produce through activities like cooking or cleaning.
Outside, these chemicals usually disappear naturally, but how? Thanks to the infallible formula: UV rays from the sun, water vapor and ozone.
When these three components come into contact, they produce hydroxyl radicals (OH), which are highly reactive molecules largely responsible for the “chemical cleaning” of the environment. That is why they are often called “cleaners” of the atmosphere.
However, indoors it is difficult to have a high concentration of hydroxide radicals, and it is the ozone filtration from the outside that causes the oxidation of the chemicals in the air.
At least that’s what we thought so far.
New study
Professor Jonathan Williams, an expert in atmospheric chemistry at the Max Planck Institute who led the new study, told BBC Mundo: “We’ve always sought to understand how the atmosphere cleans up, and it’s an amazing mechanism that we understand very well.”
So far, research into confined spaces has focused on components emitted from furniture, paints, and curtains. Until they realize that the one thing all living quarters have in common are humans.
“So we thought about how their presence would affect the interior atmosphere.
All knowledge, measurements, and instrumentation that has been traditionally used in these external atmospheric studies have been applied in a closed environment.
“We conducted our experiment in an ideal, controlled environment, because we wanted to determine what only came from humans. This is the first time this has been done,” explains BBC Mundo Nora Zanoni, doctor in chemistry and member of the Institute of Atmospheric and Climate Sciences in Bologna. (Italy) and first author of this study published in the journal Science.
To do this, they used a room made entirely of stainless steel, a “climate control room” in which only the subjects, two women and two men, were involved in the experiment.
“I must say it looks very dreary, because it has no furniture, no carpeting, nothing. We even made sure to wash the clothes the participants were wearing with fragrance-free detergent to make sure they didn’t come off anything, they were given special toothpaste. Check everything carefully,” says Williams.
They conducted tests at different temperatures and humidity, changing the participants’ clothes to show more or less skin, as well as the levels of ozone entering the metal chamber.
The more exposed the skin, the greater the oxidation
After exposing the participants to different amounts of ozone, they found that hydroxyl radicals (OH) were generated. “We were surprised because it generated a lot of things, it was a really big focus.
They discovered that ozone interacts with human skin.
“There is an oil that our skin naturally produces and that’s what keeps it looking fresh, so ozone interacts with one of its main ingredients,” William explains.
At this point, a chain reaction occurs. The ozone reacts with the oil in the skin, which results in other gaseous molecules being emitted into the air which in turn react again with the ozone. This is when OH radicals are produced.
The more exposure the skin has, the more hydroxide radicals, the more detergents are generated in the atmosphere.
“Aura” around us
To better understand and see what this field of OH radicals looks like around us over time, they created a kinetic chemical model at the University of California (Irvine, USA) with a fluid dynamics model from Penn State University (USA).
With the two models, they saw how the oxidation field produced by the subjects varied with different ventilation and ozone conditions.
“From the results, it is clear that OH roots were present in abundance and formed strong spatial gradients,” the study says.
The graphic model imagining the oxidation field looks like a kind of flame of different colors spreading out from our bodies.
Looking at the images reminds us of what in some spiritual beliefs is called an “aura,” a colorful field of energy that surrounds us.
A somewhat esoteric view of the topic that Williams does not share.
“It’s a good visualization of what the terrain actually looks like,” he says. “But it has nothing to do with these unscientific things.”
“The gradients – the different values and therefore the different colors – that we observe are consistent with the empirical evidence of the chemistry we are measuring. So we had the confidence to show that this appeared around humans,” notes Mr. Williams.
Implications for the future
though gentlemen. This is the first step, Williams and Zanoni tell us, and they stress the future significance this discovery could hold in many areas of our lives.
“In real environments, we have many sources, and the chemistry is more complete, but we already have a baseline that can help, for example, mitigate the buildup and concentration of toxic indoor products and improve air quality,” explains Nora Zanioni.
She added that although the study focuses on chemistry, “another area is to see its effects on people’s health, and while we still need more studies, this really does represent a way forward.”
“In terms of health impacts, it’s important, especially after the pandemic, when we know we’ve all had to stay home for a long time,” says Zannoni.
To study the materials, paints, furniture, and toxic substances they contain, can also mean a change.
“So far, the sofa has only been tested for toxics by testing the sofa itself. Now you can test it with someone on it, because the emissions from the sofa will reach you and rust on your rust, and they will feel doubly shifted somehow,” says Williams.
Dr. Znouni points out that although this is not the field they study, they have considered that the oxidative field around us can affect relationships between people.
“We often talk about the fact that part of our communication is a chemical, and there is a chemical connection in personal exchanges. So if everyone has this oxidation domain, depending on how it develops, it may affect the domain of others,” Zannoni says.
It concludes, “It could affect each other’s sensitive functions in some way.”