We evaluated the relationship of lead (Pb) using high precision Pb isotopes from ambient air particulates and dust fall accumulation in 59 residences in Sydney New South Wales Australia by the Petri Dish Dust method (PDD) to determine if the dust is a reliable indicator of exposure in cases where air Pb data may not be available. Over the period 1993-2002, Pb values in air samples were higher in winter whereas the Pb loadings for PDD values were slightly higher in spring and summer. These differences are probably the result of differences in sampling times of the air particulates (24-h) and PDD (~3 months). There was no seasonal or suburb effect for the isotopic ratios. Both air and PDD samples showed a strong increase in 206Pb/204Pb over time. PDD data were predicted by the air data (p<0.001) and provide a useful adjunct in monitoring exposures.