On Tue, 03 Jun 2008 10:28:16 +0100, Frank Erskine
wrote:

It would be interesting to see actual statistics (not mere opinions)
of how many people have suffered from lead poisoning due to the use of
lead pipes and lead/tin solder.

There have certainly been a number of recorded cases from the early
1900's, but all in areas where there was soft water plus extensive
lead piping and stagnation water which had been in pipes overnight was
used to make infant feed. I think some cases came from Liverpool.
Most cases though came from Publicans and their families where the
first draw of beer (or worse - cider) through the then lead pipes was
drunk by the family (rather than being thrown away).

With copper pipes/lead solder the exposure is highest immediately
after installation and drops over the next 5 years to a stable level.

Australia has few lead pipe installations installation so studies
there tend to be of copper/lead solder. Two are "Metals in Drinking
Water from New Housing Estates in the Sydney Area
Rajaratnam, Winder and An"

"Metals in drinking water were measured in 95 new houses less than 18
months old in the Sydney metropolitan area. Three samples
(first-flush, post-first-flush, and fully flushed water) were
collected from each house, and “control” samples from the five Sydney
Water points that supplied the houses, a total of 326 samples. They
were analyzed for Pb, Cu, Mn, Zn, Cd, and Al. At the supply points,
the levels of all metals were at or below Australian Drinking Water
Guidelines (ADWG). In the houses, metal levels varied. Of the
first-flush samples, Pb was above ADWG in 60% and above US EPA
Guidelines in 81%, Cu was above ADWG in 12%, and Cd was above ADWG in
4%. Of the post-first-flush samples, Pb was above ADWG in 24%, Cu was
above ADWG in 18%, Cd was above ADWG in 1%, and Zn was above ADWG in
1%. The other metal contaminants (Mn and Al) were within ADWG. In
fully flushed water, the levels of all metals were well below ADWG."

and

"Effect of plumbing systems on lead content of drinking water and
contribution to lead body burden."
Gulson BL, Law AJ, Korsch MJ, Mizon KJ

"Stable lead isotopes and lead contents in drinking water from a
number of Australian cities have been measured to determine the
contribution of drinking water to body burden. Lead contents are
generally 2 micrograms/l and thus contribute an insignificant amount
to the lead budget in humans in Australia. First-flush and running
water samples taken at intervals of up to 10 min show that equilibrium
is reached within 1 min or approximately 10 l by volume. There is,
however, large variability in both lead content and isotopic
composition within the first minute which brings into question the
reliability of the recommended sampling time of 30 s. Extremely large
isotopic differences between individual dwellings within the one city
and between dwellings and the storage tanks for the water supply are
attributed to differences in lead residing in the plumbing within the
dwellings, usually from lead solder in brass fittings. Isotopic
analysis of solder and water from two dwellings confirm this
relationship."

Leaving the cold tap running for 1 minute after it hasn't been used
for some time (eg overnight) seems to be effective in eliminating any
problem but lead in drinking water remains a relatively small source
for lead in humans.