EPA-Expo-Box (A Toolbox for Exposure Assessors)
Soil and Dust
- Fate & Transport
- Calculation Tools
Sources and Releases
Soil can become contaminated as a result of direct or indirect discharges from industrial, commercial, or residential sites; deposition of contaminants from the atmosphere to soil; erosion of soil and runoff flow; and other processes. Sources of contaminants to indoor dust can include use of consumer products or emissions from building materials or furnishings. Contaminants in outdoor soil could also be tracked indoors, contributing to the level of contaminants in household dust.
What is Household Dust Made Of?
Household dust is made of dirt, pollen, human skin and hair follicles, pet dander, insect parts, cooking and heating residues, and various pollutants. These pollutants can include flame retardants (used in upholstery coatings), toxic byproducts of cigarette smoke, pesticides in household chemicals, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals such as lead.
Contamination of soil and dust can occur from anthropogenic sources or natural sources.
- Anthropogenic sources of soil contamination might include the rupture of underground storage tanks, application of fertilizers and pesticides, oil and fuel dumping, leaching of wastes from landfills, and direct discharge of industrial wastes to the soil.
- Natural sources that could impact soil systems include volcanic activity, hurricanes, forest fires, or earthquakes. These natural disasters can cause dramatic changes to the landscape and have devastating impacts to agriculture and can leave behind significant amounts of contaminated dust and debris.