Indoor plants are air purifiers and this results in reducing the risk of headaches and catching the common cold. They also improve sleep and decrease allergies and blood pressure. Many household products and building materials contain toxic substances. Formaldehyde is found in glue, pressed wood and fire retardants and is said to cause cancer and allergic reactions. Benzene is inhaled and is found in glue, paint and detergents. It is associated with many health problems including cancer. Trichloroethylene is found in building materials, solvents and glue. It causes damage to the central nervous system causing fatigue and blurred vision. It is also said to cause cancer and birth defects. Zylene and Toulene is found in lacquer, glue and nail polish and is irritating to the gastrointestinal system, the kidneys and the nervous system. Ammonia is found in household cleaners and excessive exposure causes headaches and nausea. Those with asthma and allergies are particularly affected. After all this doom and gloom, do pot up some plants for your home and don't forget the drip trays. Ferns will do particularly well in the bathroom and shower.It is interesting to know that some research is being done regarding trees which are planted on road verges as they are thought to neutralize the toxic effect of exhaust's carbon monoxide. 'Mother Nature' cures are to be admired.