Estimation of dust ingestion rates in units of surface area per day using a mechanistic hand-to-mouth model

ABSTRACT

In order to provide dust ingestion rates that can aid the interpretation of indoor dust measurements as surface loadings (i.e., units of µg/m²), dust ingestion rates have been developed for various age groups on a surface area basis. The approach incorporates a hand-to-mouth mechanistic model that was previously developed to estimate dust ingestion rates in units of mg/day. The analysis resulted in estimated mean dust intakes that range from 0.0032 m²/d (for teenagers) to 0.061 m²/d (for toddlers) at residential settings assumed to be comprised of 50% hard surfaces and 50% soft surfaces. Intake rates assuming 100% hard surfaces and 100% soft surfaces are also presented. The values provided are intended to assist the interpretation of indoor dust investigations where substance content in dust is presented as surface loadings rather than bulk dust concentrations.

KEYWORDS:

• dust ingestion
• Canadian population
• risk assessment
• hand-to-mouth

Funding

This project was internally funded by the authors, but was based largely on a previous study funded by the Contaminated Sites Division of Health Canada.