Indoor Plants improve the quality of air within your home. Indoor Plants remove Carbon Dioxide from the air, and the plants produce fresh clean oxygen. According to a 1989 NASA study, plants also remove cancer-causing pollutants like formaldehyde and benzene from the air. Items around your house that produce pollutants in the air include; paint, varnishes, cleaning products, mold and mildew. The larger the plant and leaves, the greater the impact on air quality. Plants also have a positive psychological effect on home owners.