Common day household activities release harmful toxins into our indoor environment. But indoor plants may provide a valuable weapon in the fight against rising levels of air pollution in the home. Such plants are not only decorative, but are surprisingly useful in absorbing potentially harmful gases and cleaning the air inside modern buildings. Studies generated at NASA recommend that you use 15 to 18 good-sized houseplants in 6 to 8 inch diameter containers to improve air quality in an average......