Source and occurrence of particulate lead in tap water.
Lead samples were collected at the tap from homes with lead service lines (LSLs) in a full-scale utility using both random daytime (RDT) and particulate stimulation sampling (PSS) protocols. Analysis of the results revealed two sources and occurrences of particulate lead. A first source is due to corrosion of lead-bearing elements in the premise plumbing (PP) and occurs mostly at low to moderate concentrations < 3 microg/L, with some sporadic higher concentrations (4-12 microg/L). These spikes were consistently observed and considerably increased using PSS, showing that current sampling protocols may miss a significant portion of particulate lead. The second source results from the adsorption of dissolved lead onto iron deposits in LSL/PP, and is continuously present at low to moderate concentrations. Statistical analyses were validated by physical analyses of: (i) lead scales from LSLs; and (ii) lead particles from tap aerators.
Deshommes
Elise
E
NSERC Industrial Chair on Drinking Water, Ecole Polytechnique de Montréal, Civil, Geological and Mining Engineering Dept., CP 6079, Succ. Centre-ville, Montréal, Québec H3C3A7, Canada. elise.deshommes@polymtl.ca
Laroche
Laurent
L
Nour
Shokoufeh
S
Cartier
Clément
C
Prévost
Michèle
M
D007854:Lead / Q000032:analysis*; D010087:Oxides / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis*; D012044:Regression Analysis; D012995:Solubility; D013059:Spectrum Analysis, Raman; D013997:Time Factors; D014867:Water / Q000592:standards; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
D010087:Oxides; D052638:Particulate Matter; D014874:Water Pollutants, Chemical; D014867:Water; D007854:Lead