Really?

By ANAHAD O’CONNOR
Published: January 29, 2008

THE FACTS

The claim has the ring of a myth. But environmental scientists say it is real.

The reason is that hot water dissolves contaminants more quickly than cold water, and many pipes in homes contain lead that can leach into water. And lead can damage the brain and nervous system, especially in young children.

Lead is rarely found in source water, but can enter it through corroded plumbing. The Environmental Protection Agency says that older homes are more likely to have lead pipes and fixtures, but that even newer plumbing advertised as “lead-free” can still contain as much as 8 percent lead. A study published in The Journal of Environmental Health in 2002 found that tap water represented 14 to 20 percent of total lead exposure.

Scientists emphasize that the risk is small. But to minimize it, the E.P.A. says cold tap water should always be used for preparing baby formula, cooking and drinking. It also warns that boiling water does not remove lead but can actually increase its concentration. More information is at www.epa.gov/lead or (800) 424-5323 (LEAD).

THE BOTTOM LINE

Hot water from the tap should never be used for cooking or drinking.

scitimes@nytimes.com

Source: http://www.nytimes.com/2008/01/29/health/29real.html?ex=1202360400&en=9d1c27323b1509d9&ei=5070&emc=eta1

Wow! That's an eye opener. Thanks Joe.

The older the home the greater chance of lead contamination. On new homes I have my doubts, but who knows. - Millet

I am certainly suspicious of builders and contractors or perhaps their suppliers who would sometimes substitute high quality materials with cheap stuff tainted with lead from China in building the newest homes. There are no audits.

The main source of lead in drinking water is from lead in solder used on copper pipes. The fact that most new homes are built with PVC eliminates the lead solder. Even if copper is used in new homes, the lead in solder has also been reduced (of course as you mention--anything from China that is preasembled using solder is probably suspect).

One other factor that affects the lead in drinking water is the pH of your drinking water--the lower the pH the more lead it will dissolve from your pipes.

I doubt you will find lead solder in any recent construction, but for older homes it may be something to be concerned about. Up until the 1940s lead pipe was still used for water in some areas. Lead water pipe was even used as early as the Romans as seen in the picture below (Hmm . . . now we know what caused the fall of the Roman Empire ):


In grad school I had several classes in the public health department. For one of our experiments, each student was to bring in water from various sources. Most people brought their home tap water in, but I thought I'd be funny and bring in water from the drinking fountain in in the engineering department. The joke backfired when the teacher announced to the class that if they found lead in my water that would definitely explain some things about the personality traits of engineers.

Anyway, one thing that they said that is if you are concerned about lead in the drinking water, the highest concentrations will be found when you first turn on the water in the morning after sitting in the pipes all night. They suggested letting the water run for a few seconds. I'm not sure I totally agree since you would have to let it run long enough to purge all water from the main in the street to your tap which would be more than a few seconds depending on pipe size and water pressure. The other thing you can do is invest in a reverse osmosis unit for drinking water. I put one in a few years ago (more for taste than anything else), and we use it constatantly. I even joke now that they started adding floride to our drinking water recently that I pay for them to add something that I then take out with my RO unit. Go figure . . .

Phillip

When I visited the volcano engulfed city of Pompei, Italy they had lead piping in the houses at that time. - Millet

Long ago I read about the lead problem with drinking water. One thing that stuck my mind was, as Phillip mentions, that you should let the water run some before using it to drink, or otherwise consuming it. One point of the article was that the brass faucet, and related brass fittings, contained lead, and that when the water sat in the pipe it absorbed a greater concentration of lead. It has been 20 years or more since I read this and I would guess faucets contain less, or maybe no, lead now. (but I wouldn't bet on it!) I still let the water run so that I don't drink the water that stood in the faucet (I have pvc piping), and I guess I always will.

Another facet of the lead problem is fishing sinkers. Here we catch shrimp, and some fish, with cast nets. A small rope on the bottom of the net is strung with lead "sinkers" to cause the net to sink quickly. In casting the net, most fishermen put the line in their mouths. I had never realized the danger the lead might pose, until several years ago, when I purchased a new net. It had a warning on the box telling the buyer to avoid putting the lead line (as it is called), in ones mouth. I have been throwing one this way so long that I still put the line in my mouth, but I am very careful to avoid swallowing, and I tend to spit a lot more, when casting, than I use to!

Ned

Lead sinkers are a problem in fresh water, but not in saltwater-- at least not now. In saltwater, lead carbonate controls the solubility and limits lead to about 5 ppb, but increasing CO2 in the atmosphere is changing that. As atmospheric CO2 increases, carbonate concentration in seawater is decreasing-- allowing more lead to dissolve. A change in pH of seawater by one unit could allow lead concentration in seawater to increase to near 50 ppb.

There are plenty of lead sinkers already present in saltwater to supply the lead--- I know because I lost most of them!

I cannot imagine lead fishing sinkers, nor any type of CO2 effect on lead sinkers ever having the slightest effect on the ocean. The ocean is estimated to contain 328,000,000 cubic MILES of salt water. This figure converts to 361,200,000,000,000,000,000 gallons of salt water. (3.612 X 10 to the 20th power). - Millet

The oceans, very much like some of the lakes have different stratification layers. The first 30 ft is where most of the marine ecosystems are, especially the corrals. So, literally, it is these surface layers which are severely impacted by increased carbon dioxide in the atmosphere.

That still correlates to a HUGE HUGE HUGE number, I seriously doubt any affect at all. . - Millet

The scale is the same analogy as this mathematical problem: If you wrap a string around the earth tightly, then loosen it up by one foot and form a concentric circle around the earth, by how much will it be raised from the earth's surface? What is your estimate?

The answer actually is not negligible, but measurable, and the exact value is of course 12/pi inches or approximately 3.82 inches.

The lesson here is not about mathematics, but illustrating our concepts about scales. Even though the one foot is spread the entire circumference of the earth, in fact, it can raise the string 3.82 inches off the ground. But our first instance of thought of approximate answer is almost zero or negligble, because our mind was actually computing in different scale, and we are thinking about the 3,963.2 miles average radius of the earth, and increasing 3,963.2 miles by 3.82 inches, it is negligble.

It is the same way with computations of gas concentrations dissolved in water in super massive scale. Many areas we have localized affects. Perhaps it could be just the surface layers and the interface where some important algaes are located. The difference we may not be able to sense it in our own point of view, but the slightest overall average increase equates to mass extinction of many marine species, especially in very sensitive areas wherre we have those excess fertilizers running off from farms and containers, ending up in drainage systems on to the waterways into the rivers, offloading into the ocean. See how many thousand square miles of dead zones we have in the Gulf of Mexico. You average that concentration of fertilizer pollutants it will be negligible and you are correct, but the fact is it is happening, and projected to exceed several million square miles in decades to come. Yes, in massive scales, these are negligible, but the areas affected are bigger than entire nations.