Lead isotope ratios, determined by inductively coupled plasma quadropole mass spectrometry (ICPMS), have been used to assess environmental impacts from uranium and lead mining in northern Australia. The lead isotope composition of most environmental samples contained evidence of mixing of two or more end-member components; their characteristic lead isotope ratios allowed lead sources to be unambiguously identified. The isotopic characteristics and sources identified include highly radiogenic lead (low 207Pb/206Pb and 208Pb/206Pb ratios) in sediments from the Finniss River derived from the former Rum Jungle uranium mine; relatively non-radiogenic lead (high 207Pb/206Pb and 208Pb/206Pb ratios) in the livers of magpie geese from the Finniss River floodplains, originating from lead ores via ingested lead shot; and relatively non-radiogenic lead in seagrass leaves and oyster soft tissue from the Gulf of Carpentaria resulting from dispersion of small amounts of lead–zinc concentrate from a coastal loading facility.

The combined measurement of lead concentration and isotope ratios in organisms used as bio-monitors may provide a sensitive and cost-effective monitoring tool allowing an unambiguous assessment of the source of lead in environmental samples. Data presented here shows that dispersion of trace amounts of orederived Pb produced distinctive Pb isotope ratio changes in seagrass and oysters acting as sentinel accumulators.

Studies were made of the mobilization of metals from the water-distribution systems within several types of buildings, many of which are serviced by old leadpipe mains, in Halifax, Nova Scotia. The study examined 36 single-family houses, three apaftments in a high-rise building, and one school. ln many homes, water that stood in pipes overnight developed relatively large concentrations of copper, lead, and zinc. In total,TQ'h of the standing water from single-family homes had lead concentrations exceeding the 0.01 mg/L criterion for lead in drinking water.The 30 single{amily homes serviced by municipal mains made of lead did not have significantly larger lead concentrations than the six homes serviced by other types of piping. This suggests that the source of lead in drinking water is metal dissolving from the water-distribution systems within the homes, rather than from the lead service lines. R6sum6Une 6tude a 6t6 faite sur la mobilisation des m6taux d partir des systdmes de distribution d'eau, dans divers types d'6difices d Halifax en Nouvelle-Ecosse, oit de nombreaux 6difices sont desservis par d'anciennes conduites d'eau en plomb.Cette 6tude a examin6 36 maisons unifamiliales, trois appartements dans un immeuble, et deux 6coles. Dans de nombreuses maisons, l'eau stagnants dans les tuyaux pendant la nuit a acquis des concentrations relativement importantes en cuivre, plomb et zinc. Au total, dans 7O"/" des maisons unifamiliales, ces eaux stagnantes avaient des concentrations en plomb exc6dant le critdre pour les eaux potables (0,01 mg/L). Les 30 maisons unifamiliales desservies par des conduites municipales en plomb n'ont pas mont16 de concentration en plomb significativement plus 6lev66 que les 6 autres maisons desservies par d'autres types de conduites. Ceci suggdre que le plomb d6cel6 dans l'eau potable provient du m6tal se dissolvant apartir des tuyaux d'eau dans la maison elle-m6me plut6t qu'd paftir de la conduite municipale.