You are your own threat to your air quality. (Well, one of the threats, anyway.)

Science Daily reports on the discovery that human skin oils react with ozone in the atmosphere inside your office or house to create “the Pig-Pen Effect” – a cloud of pollutant chemicals unique to each individual person:

“When the ozone is depleted through human skin, we become the generator of the primary products, which can cause sensory irritations,” said Donghyun Rim, assistant professor of architectural engineering and an Institute for CyberScience associate, Penn State. “Some people call this higher concentration of pollutants around the human body the personal cloud, or we call it the ‘Pig-Pen Effect.'”

The substances that are produced by the reaction include organic compounds, such as carbonyls, that can irritate the skin and lungs, said Rim. People with asthma may be particularly vulnerable to ozone and ozone reaction products, he said.

According to the researchers, who reported their findings in a recent issue of Nature’s Communications Chemistry, skin oils contain substances, such as squalene, fatty acids and wax esters. If a person wears the same clothes too long — for example, more than a day — without washing, there is a chance that the clothes become more saturated with the oils, leading to a higher chance of reaction with ozone, which is an unstable gas.

For example, a single soiled t-shirt helps keep ozone out of the breathing zone by removing about 30 to 70 percent of the ozone circulating near a person.

“If you have clean clothes, that means you might be breathing in more of this ozone, which isn’t good for you either,” said Rim.

Rim said that the research is one part of a larger project to better understand the indoor environment where people spend most of their time.

“The bottom line is that we, humans, spend more than 90 percent of our time in buildings, or indoor environments, but, as far as actual research goes, there are still a lot of unknowns about what’s going on and what types of gases and particles we’re exposed to in indoor environments,” said Rim. “The things that we inhale, that we touch, that we interact with, many of those things are contributing to the chemical accumulations in our body and our health.”