Abstract
Estimation of "permissible upper-bound concentration (PUC)" of 12 trace elements (V, Cr, Mn, Ni, inorganic As (iAs), Se, Sr, Mo, Ag, Cd, Sb and Ba) in house dust for preventing excess health risk for children was attempted. Upper-bound intakes from diet (including drinking water) and soil were estimated from the published data for each of the trace elements. They were subtracted from the corresponding tolerable daily intake (TDI) and the residual intake was divided by upper-bound house dust ingestion rate (100 mg/day) of the US EPA to find "PUC". The "PUC" could not be found for iAs, Se, Mo and Cd because their upper-bound dietary intake levels exceeded TDI. The "PUC" of the rest of the elements (unit: µg/g) were V (9.4×102), Cr (4.5×103), Mn (1.9×102), Ni (1.6×103), Sr (6.8×104), Ag (9.0×102), Sb (50), Ba (3.1×104). The reported 95 %tile concentrations of Mn (551 µg/g) in house dust exceeded the "PUC", and those of Sb and Ni had relatively small margin. Since the "PUC" was estimated as highly conservative upper-bound value, no immediate harm was expected for the exposure to these trace metals via the house dust ingestion. However, it may be warranted to pay some attention to the levels of these elements in house dust.
