The model applies standard residential exposure assumptions. Inhalation intakes were calculated based on this McKone and Knezovich model. The hazard quotient, an index reflective of relative risk from a given pathway, is calculated to be 0.005 for acute exposure and 0.023 for chronic inhalational exposure. Since the risk is found to be less than one, it is considered minimal. As stated previously, Andelman, et.
Drinking water is the other main residential use.
Therefore, the remaining domestic uses such as cooking, laundry, and dishwashers all combined contribute much less than one third of total water usage and are individually insignificant factors in exposure. Ingestion is not a potential pathway of exposure since trailer park residents are being provided bottled drinking water. No animal or human studies were available in the toxicological profiles with known systemic toxic effects from specific dermal doses. Therefore, no reference dose exists. The same subpopulations are subjected to both dermal and inhalation exposure, and thus the combined exposure must also be considered.