Soil ingestion by children and adults reconsidered using the results of recent tracer studies

Estimates of human exposure to soil are often needed to investigate potential risks to public health from toxicants released into the environment. Using the results of two recent tracer studies, estimates of average daily soil ingestion in young children and over a lifetime were ascertained. After establishing the distribution of the recoveries of the tracers in adults, the most reliable tracers were identified using an analysis of variance and Tukey's multiple comparison procedure. The identified reliable tracers were then employed to derive estimates of mean daily soil ingestion in young children. Ingestion rates were first adjusted to address the age differences of the children enrolled in the studies. A mean daily intake and variance were then determined. Estimates of soil ingestion over a lifetime were established based on levels determined in children.