With the increase of air pollutants in our environment, sometimes we tend to just stay in the comfort of our homes, but a new study shows that the air we breathe inside our houses is oftentimes more polluted than the air outside.

"When we think of the term 'air pollution,' we tend to think of car exhausts or factory fumes expelling grey smoke. However, there are actually various sources of pollution that have a negative effect on air quality, many of which are found inside our homes and offices," said study author Dr. Prashant Kumar of the University of Surrey in a statement.

According to the study published in the journal Science of the Total Environment, household air pollution is 9th in the rank of Global Burden of Disease Risk. Nearly 4.3 million deaths worldwide in 2012 are associated with indoor pollution, significantly higher than the 3.7 million deaths linked with outside pollution.

Researchers said people who live in urban areas tend to spend 90 percent of their time indoors and this has been associated with "Sick Building Syndrome." Sick Building Syndrome, according to a past study published in the Indian Journal of Occupational and Environmental Medicine, is the situation where people who lives or work in a building experience acute health- or comfort-related that seems to be directly linked to the duration of their stay in the building.

Centers for Disease Control and Prevention reported that indoor air pollution can cause eye, nose and throat irritation. In some case it may also lead to chronic heart and lung problems and cancer. These indoor air pollutants include but are not limited to wood smoke, tobacco smoke, gas-burning furnaces, gas-burning appliances, radon gas, mold and allergens.

With dangers of indoor air pollution, researchers advice people to use preventive measures to ensure that the air we breathe in our homes are safe. Buying and installing air quality monitoring devices can be helpful in tracking and maintaining indoor air pollution. Simple solutions such as opening a window can also help reduce indoor air pollution if done at the right times.