If you're working in a tense environment, you and your colleagues may be communicating stress to one another without even realizing it.

A new study published in the online journal PLoS One reveals change in brain action when people are exposed to sweat from others who have been in a tense condition. Researchers found that people may turn into more alert to probable threats when inhaling this "stress" sweat.

The results advice that we can notice others' stress just by breathing in their sweat, said Lilianne Mujica-Parodi, assistant lecturer of biomedical engineering at Stony Brook University in New York and lead author of the study, in an e-mail.

Researchers took sweat trial from 144 people who had put themselves in the somewhat stressful condition of tandem skydiving for the first time. Each participant was strapped to an specialist skydiver, and each pair jumped from 13,000 feet. Control samples were taken from public who had run on a treadmill.

In the first trial, sweat samples from the experimental and control conditions from 40 donors were known to eight males and eight females while their brains were scanned using functional magnetic resonance imaging. This procedure was repeated with 40 more contributor and a group of 16 different participants with the same gender ratio.

Imaging results point out that the amygdala, an area of the brain associated with reaction, was more energetic when exposed to the skydivers' sweat than to the runners' sweat. An additional test showed that participants could not distinguish between the sweat samples based on smell alone.