From plumbing lead piping

Lead in Drinking Water. The naturally soft, slightly acidic, plumbosolvent water of the Loch Katrine water supply for the Glasgow area was recognized many years ago to release lead from the lead pipes and tanks in the domestic plumbing of the Victorian and subsequent (even post-World War II) eras. ... 

Lead levels ranging between 10 and 30 pg/L can be found in drinking water from households, schools, and office buildings as a result of plumbing corrosion and subsequent leaching of lead. The combination of corrosive water and lead pipes or lead-soldered joints in either the distribution system or individual houses can create localized zones of high lead concentrations that exceed 500 pg/L (EPA 1989f). 

ORIGIN OF NAME The name "lead" is the old Anglo-Saxon word for this well-known element, and the symbol for lead (Pb) is derived from the Latin word plumbum, which is also the root word for "plumber," related to the use of lead pipes in ancient Roman plumbing systems. Some of these lead pipes can still be seen in parts of modern-day Rome. 

A plumb bob, a heavy weight attached to a string and used by carpenters and surveyors to establish a straight vertical line, gets it name from the lead (plumbum, Pb) that is still sometimes used as the weight. Plumbers got their name because they once worked with lead pipes. 

The grounding of household electrical systems to the plumbing can increase corrosion rates and the subsequent leaching of lead from the lead solder used for copper pipes. Areas where the pH of the water is less than 8.0 may have higher lead drinking water levels as well. 

Together with the aqueducts, the Romans also advanced the technology of water distribution from the aqueducts to multiple sites—baths, residences, fountains, etc. Plumbing is derived from the Latin word plumbum which means lead. Piping used in Roman times included lead pipes, masonry channels as well as earthenware pipes. The water was delivered to baths and some public homes at a constant rate. The cost of the water was charged based on the pipe cross-sectional area, which served as a restriction orifice (Chanson, 2002,2008). 

As illustrated in Figure 7.1, tap water itself is a solution containing many things. It has some dissolved oxygen and carbon dioxide in it. It almost certainly has some dissolved calcium compounds, making it hard. There may be a small amount of iron present, which causes the water to stain clothing. It contains some chlorine, added to kiU bacteria. In unfavorable cases, it may even contain some toxic lead and cadmium dissolved from plumbing and the solder used to connect copper pipes. Thus, it is clear that many of the liquids that people come in contact with are actually solutions. 

Water can eat away at and release lead from plumbing systems. The characteristics of the water, such as its pH and hardness, affect how corrosive it is, and therefore how much of the lead it carries away. Lead pipes have not been used for decades, but many homes are still connected to municipal services containing old lead pipes. Although lead solder has been outlawed for use in residential plumbing systems since 1986, it nonetheless joins together the copper pipes in many homes. Brass faucets can still contain up to 8% lead. These lead sources can be present in our water distribution systems or in our homes themselves. 

The main source of lead in drinking water is from lead service pipes and the lead pipes inside dwellings and in the older districts of some Cities and Towns, up to 90% houses may have a lead pipe. Problems can also be caused by lead leaching from devices, pipes and plumbing components made of brass, and from lead-containing solder. 

It is important to note that large numbers of water systems in the U.S., having no lead service lines or interior lead piping, required some form of enhanced corrosion control as a result of the Lead and Copper Rule, due to a combination (not differentiable from the monitoring data) of leaded brasses and soldered joints in copper plumbing. Therefore, the significant lead release observed in the AWWARF study represented lead contamination from waters already adjusted for some corrosion control, and would not represent nearly a worst-case scenario as may be present elsewhere in North America or Europe. 

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