Formaldehyde is naturally occuring and man-made.  It is a gas or chemical used in many products.  It can be harmful and/or fatal depending on its levels.  It is typically found in pressed woods, cleaners/disinfectants, permanent-press fabrics, nail polish and hair care products, cigarette smoke, in morturaries as a preservative and many other products. 

 Other names of formaldehyde include: Quaternium-15; 2-bromo-2nitropropane-1,3-diol; imidazolidinyl urea; diazolidinyl urea; formalin; methanal; methyl aldehyde; methylene oxide; morbicid acid and oxymethyline.  It is a known human carcinogen.  In small doses it is not harmful, but with several products in the same area, like your home, it can be very harmful.  It can cause cancer and leukemia if a person is subjected to continual exposure.  Everyone reacts to different levels of formaldehyde, check out OSHA's website for further details regarding toxicity levels.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10078

Be safe - know what's in your environment.  If you would like other health topics reviewed, please contact me at BeWell@integra.net