For compounds for which the critical effect is believed to have a threshold of exposure, two key factors are considered in the setting of soil guidelines in Canada. Secondly, a multimedia approach to guideline development has been used to reflect the multimedia nature of exposure. However, in the case of the commercial land use, a different exposure scenario is used to account for the expected differences in use patterns in this setting versus residential ones. For the industrial setting, an adult is used as the receptor.
Ingestion is the principle and primary route of exposure in all settings.