US EPA

This update includes new information on soil and dust ingestion that has become available since the Exposure Factors Handbook: 2011 Edition was released. The recommended values have also been revised, as needed, to reflect the new information. This chapter explains the concepts of soil and dust ingestion, soil pica, and geophagy; defines these terms for the purpose of this handbook’s exposure factors; and presents available data from the literature on the amount of soil and dust ingested.

Ingestion of soil and dust is a potential route of exposure to environmental chemicals for both adults and children. Children, in particular, may ingest significant quantities of soil and dust due to their tendency to play on the floor indoors and on the ground outdoors and their tendency to mouth objects or their hands. For example, children may ingest soil and dust through deliberate hand-to-mouth movements, or unintentionally by eating food or mouthing objects that have dropped on the floor. Adults may also ingest soil or dust particles that adhere to food, cigarettes, or their hands. Thus, understanding soil and dust ingestion patterns is an important part of estimating overall exposures to environmental chemicals.

This purpose of this update is to provide new information on soil and dust ingestion that has become available since the Exposure Factors Handbook: 2011 Edition was released. The recommended values have also been revised, as needed, to reflect the new information. Lastly, understanding soil and dust ingestion patterns is an important part of estimating overall exposures to environmental chemicals.

U.S. EPA. Exposure Factors Handbook Chapter 5 (Update): Soil and Dust Ingestion. U.S. EPA Office of Research and Development, Washington, DC, EPA/600/R-17/384F, 2017.