Lead in Drinking Water

Lead in Drinking Water – A Discussion

We saw the news items recently that indicated that the Government of Ontario is concerned that the levels of lead in municipal water supplies are higher than the Provincial standards, and they have requested that about thirty municipalities across the province test the water in peoples’ homes.

There have been several articles in the Recorder and Times and numerous other papers regarding this, and I thought it would be appropriate to take a more detailed look at the issue and understand some of the background of the issue.

Lead has been around for a very long time, and has a history of use to man for millennia. In the twentieth century physicians began to realise that extensive exposure to lead caused neurological impairment (brain damage) to young children and was particularly dangerous to pregnant women. Human exposures through handling metallic lead such as fishing weights or working with stained glass are of no great concern. Our concerns are areas in which lead can be readily ingested, and this occurs in inhaling or breathing lead-containing dust, children chewing on lead-based paints, and of course, through food and drinking water. Since the elimination of lead additives to gasoline nearly twenty years ago, and the discontinuing of lead-based pigments in consumer paints, the first two are not significant contributors for most Canadians. This brings us to food and drinking water.

Lead levels in food are very strictly controlled and are generally at or below the limits of detection by modern analytical techniques. The levels in drinking water are set by the Ontario Government at 10 micrograms per litre. To put this in perspective, this represents about one-half of a BB pellet dissolved in a typical backyard swimming pool. The water entering the St. Lawrence is monitored at Wolfe Island, near Kingston, and the typical level seen there is 0.016 micrograms per litre, or about one five-hundredth of the allowable amount.

So if lead is so low coming into the Brockville water supply, where does it come from? Up until the early 1950s, lead pipes were in common use for water supply lines. They were easy to install, join, repair, bend, and the lead did not give a taste to the water. However, as the toxic effects of lead were understood, its use in drinking water pipes was discontinued and indeed Brockville has reviewed its use of lead and has determined that lead was not used for water distribution. However, there may be some homes primarily south of the railroad tracks where the line from the supply main to the house is still lead.

Now we get to the chemistry part… the inside of water supply lines typically becomes coated with scale, deposits of calcium and magnesium, and these deposits lessen the amount of lead which can dissolve in the water. Lead is less soluble in cold water than hot, so use cold for your cooking and drinking. As well, lead has a pH point (pH is a measure of acidity we will discuss in a future column) where it is minimally soluble in water, which is pH 7.6, and it happens that Brockville City water is pH 7.6 So what this all means is that we are lucky that the water chemistry works in our favour and we are not at great risk here.

Having said that, there are a couple of additional points to consider. Most homes built in the past fifty years or so used copper plumbing that was soldered together. Lead was a component of solder until the late 1980s. The amount of lead that dissolves from solder into water is thought to be very small, because of the low area exposed to the water, and we already learned that the chemistry is on our side.

If you live south of the tracks, and if you suspect that you have a lead connection, the recommended practice is to flush the toilet or run the shower before taking water that had been sitting overnight from the tap; this is something most of us would do anyway. Tests have been carried out in twenty houses in Brockville; all were within the Provincial standards and all but one were below 3 micrograms per litre.

The issue of lead in well water in Leeds-Grenville is more complicated, as our area includes limestone, Canadian Shield granite, and sedimentary soil, and each has its unique chemistry. The best information seems to be that there is very little lead in groundwater in Eastern Ontario. Go to the Health Unit website, www.healthunit.org/water/infosheet/aquainted.htm and www.healthunit.org/water/test/lead.htm to find out more about maintaining your well in good condition, and about lead testing and availability.


If you travel to Central and South America and bring back a highly-coloured piece of glazed pottery, use it for decoration only. Coloured glazes are often made from lead, cadmium and chromium, which make wonderful colours but are all very toxic. Many of our favourite beverages, such as fruit juices and wines, are very acidic (they have a low pH) and will extract the toxic metal from the glaze.

So use caution in your exposure to lead, run your taps, use cold water for cooking and drinking, and if you are really concerned, ask for a test.

Hydrogen as Automotive Fuel

Many of us have been told, and have figured out that about the only fuel that doesn’t give off carbon dioxide as it burns is hydrogen. So it would make a great fuel for a motor vehicle, right? Well, as with everything, it is a good news/bad news story.

Hydrogen does indeed burn nicely, giving off water vapour and heat. Most current internal combustion engines can burn hydrogen with relatively minor modifications to the carburetor, and there would be no need for a catalytic converter. However, there are two big issues about hydrogen: how do you make it, and how do you store it?

Almost all industrial-scale hydrogen is currently made from natural gas, or methane. This process generates carbon dioxide as well as hydrogen. If we are thinking about hydrogen as a motor fuel, we will need more methane than is currently available, and we will generate a lot of carbon dioxide. So… how else can you make hydrogen? You can pass electricity through water, and you get hydrogen and oxygen, lots of both. But you had better have your own generating plant, because you will need a lot of really cheap electricity. You don’t really want to burn anything to make your electricity, such as coal, oil, or natural gas, as you will make more carbon dioxide, so you are stuck with hydro and nuclear, our current favourites, or perhaps wind, solar, or tidal electricity, none of which gives enough power, at current generation efficiencies, to do the job. Fusion power is several years in the future at least. Seeing as we have dammed most of the rivers that are suitable, we are looking at nuclear – generated electricity as the most practical option. I know nuclear – generated electricity is like a red flag to a bull to many members of our community, but let cool heads prevail and let’s discuss it in reasonable terms (in another column).

After you have made your hydrogen you need to be able to carry enough in your vehicle to give about 400 – 500 km. driving. The current methods include a large high pressure (200 to 350 atmospheres, an atmosphere is about 15 psi) tank, weighing up to hundreds of kilograms, or a lower pressure tank (10 to 100 atmospheres) containing metal hydrides, which store hydrogen like a sponge, and give it up with gentle heating. GM, Toyota and Honda are all researching various promising hydride technologies. Both of these storage systems are going to fill the trunk of a standard car or mini-van. Another method of hydrogen storage is as a cryogenic (very very cold) liquid. This gives a greater energy density, but at the expense of having to cool and compress the hydrogen to begin with, then having to insulate the tank, which would be at about -250°C. Another issue would be filling your tank, not simply a matter of sticking a nozzle in a trapdoor in your rear fender as we are accustomed to doing. As technologies emerge, the infrastructure will need to be put in place to make hydrogen motor fuel available in the right form, requiring huge investments by supplying companies. Governor Schwarzenegger of California and Premier Campbell of British Columbia have just committed to a “hydrogen highway” from Los Angeles to Vancouver, with hydrogen fuel available along the Pacific Coast. There is also the huge psychological obstacle I’ll call the Hindenburg Factor – remember the German dirigible which crashed and burned spectacularly in 1937 (or the movie of the same name in 1975) and many people will say “No way!”. Having said that, the hydrogen industry as it exists today has an excellent safety record.

Despite these rather daunting technical challenges, several automobile manufacturers are going ahead with hydrogen-fuelled vehicles. BMW plans to introduce the Hydrogen 7, which will incorporate an internal combustion engine capable of running on gasoline for 500 km., or hydrogen for 200 km. Ford is marketing the “Edge”, a crossover SUV that is powered by plug-in hybrid fuel cell system that runs on hydrogen in a high pressure tank and goes 325 km between fill-ups. Not sure where they will fill it up in Brockville for a while yet.

One of the more promising areas where hydrogen-fuelled vehicles will be the right choice is urban transit. Buses work in a clearly-defined radius, they return to a central location where specialised fuelling can be set up, they work in cities where air quality can be a serious issue, and they are large enough to have room for special storage tanks.

So where does all this leave us? It is easy to say that hydrogen is the fuel of the future, and is pollution-free, and indeed it looks great on the surface. But as we can see, there are many issues and technological hurdles to be overcome before we can bid the gasoline and diesel internal combustion engines goodbye.