Abstract
House dust originates from both internal and external sources and has been identified as one of the primary sources of lead exposure for children (
http://www.epa.gov/lead). House dust is also a repository for pesticides, flame retardants, and other chemicals used indoors and tracked in the house from outdoors. Organic contaminants in house dust originate from external and internal sources and adsorb or partition to indoor particulate matter that later settles as dust. Pesticides become associated with house dust primarily through interior use of pest control formulations, intrusion of vapors from foundation and crawl space treatments, and track-in of lawn and garden chemicals. Polycyclic aromatic hydrocarbons (PAHs) derive from indoor sources such as combustion, cooking, and smoking, as well as track-in of contaminated yard soil or residues from garage floors. Flame retardants, such as polybrominated diphenyl ethers, are commonly applied to many products found within homes (e.g., TVs, computers, furniture, and carpets). Once indoors where they are protected from environmental degradation, pollutants associated with dust persist for long periods, particularly if the dust is embedded in carpets. Thus, indoor dust is collected and analyzed in some studies as an indicator of human exposure in the interior environment.