Poison Pipes?

Increasing lead levels require alternative action.

Lead is a soft, malleable metal widely used through 6000 years for decorative and utility purposes, including plumbing, jewelry, cosmetics and crystal. Lead can also be toxic. The first recorded documentation of its toxicity was in 2000 BC.

The fall of the Roman Empire has been partly attributed to mental deterioration through lead poisoning, caused by exposure to the advanced lead-based plumbing systems and wine fortified by lead acetate. Vitruvius, who was engineer to Julius Caesar during the period 49 to 44 BC, reported, “Water is much more wholesome from earthenware pipes than from lead pipes. For it seems to be made injurious by lead, because white lead paint is produced from it; and this is said to be harmful to the human body.”

Nowadays, Health Canada says that even small amounts of lead can be hazardous to human health. The US Environmental Protection Agency says that lead in drinking water can cause a variety of adverse health effects. More specifically, “In babies and children, exposure to lead in drinking water above the action level can result in delays in physical and mental development, along with slight deficits in attention span and learning abilities. In adults, it can cause increases in blood pressure.”

Despite this knowledge and public concern, 2050 years after Vitruvius’ enlightened analysis; we are finding unsafe levels of lead in our water delivery systems. This year alone, alarms have been raised about high levels of lead found in water samples from several cities across Canada.

In June 2007, 1 in 4 London homes failed provincial safety standards for lead. The Ontario Chief Drinking Water Inspector called for testing in 36, out of 445, municipalities. These tests revealed that almost half of the municipalities had some lead levels higher than the Health Ontario guidelines, even after flushing for 5 minutes. Embarrassingly, high lead levels were also found in drinking water in the Ontario legislative building.

Following the summer recess, mandatory tests on the drinking water in some Ontario schools revealed high levels of lead. For example, the Hamilton Spectator reported on September, 18, 2007 that, “The Halton District School Board is flushing water pipes daily for up to 35 minutes in five of its schools, after tests flagged high levels of lead.”

So, how does lead get into our water system? Lead does not enter the water system from source water but can be picked up en route from the treatment plants to the tap. The lead is leached from distribution pipes and household plumbing fixtures that contain lead.

Water treatment plants do treat the water with chemicals to reduce the corrosion as the water passes through the delivery system. However, newer chemicals (chloramines and ferric chloride) have been introduced into drinking water with the intention of reducing chlorine disinfectant byproducts (DBPs), some of which are carcinogenic trihalomethanes (THMs).

However, there is evidence that these newer chemicals introduced into drinking water can be causing increased corrosion and spawning new toxins. Marc Edwards, corrosion expert at Virginia Polytechnic Institute and State University, says, “The release of lead due to corrosion of solder and brass is consistent with experimental results involving chloramines. For certain brasses and solders, the corrosion can be extensive, although it is difficult to predict…The effectiveness of different corrosion inhibitors in the face of changing disinfection practices is still not resolved,” he says. Edwards goes on to state that, “We barely understand the effects of chloramines on plumbing.”

Research is indicating that these changes in disinfectant methods could be having the opposite effect to what was intended. Chloramines may produce increased concentrations of disinfection byproducts with toxicities far more potent than those currently being regulated.

A recently discovered disinfection byproduct (DBP) found in U.S. drinking water treated with chloramines is the most toxic ever found, says Michael J. Plewa, a genetic scientist at the University of Illinois at Urbana-Champaign who tested samples on mammalian cells. “This research says that when you go to alternatives, you may be opening a Pandora’s box of new DBPs, and these unregulated DBPs may be much more toxic, by orders of magnitude, than the regulated ones we are trying to avoid.”

The dangers of water treatment chemical changes are recognized in a technical guideline document, posted for review on the Health Canada website in April 2007. “Any treatment change that will have a chemical, biological or physical impact on the distributed water should be carefully monitored in the distribution system. Lead corrosion and lead levels are easily influenced by small changes in the quality of the water distributed.”

The Ontario Drinking Water Advisory Council produced a Review of Drinking Water Corrosion Control Measures at the request of the Minister of the Environment in reaction to the Health Canada proposed guidelines. The review makes recommendations for better water monitoring and changes to eliminate lead. The long-term recommendation is the replacement of lead pipes and changes to the water chemistry to make distributed water less corrosive.

Although lead pipes have not been installed for many years, older areas in municipalities across Canada still have the original lead pipes, some of which were installed 150 years ago. Toronto is spending $7 million annually to replace pipes containing lead but it will take 13 years to complete.

Elizabeth Brubaker, executive director of Environment Probe, says the estimated cost for maintaining, refurbishing, and expanding Canada’s water and wastewater infrastructure in the coming decades could be as much as $90 billion.

Ontario, like other Canadian jurisdictions, set their own regulations regarding testing and acceptable levels of contaminants in water. Although Health Canada has guidelines for permissible levels, these guidelines are only suggestions and not enforceable on the provinces and territories.

Levels of lead could be higher outside Ontario. Engineer Ian Douglas, with the city of Ottawa Drinking Water Services, says, “Across the country, there has been little in the way of water sampling. So we don’t know how big the water problem could be.”

This is emphasized in the following extract taken from a report by CBC news March 2007. “The City of Charlottetown is planning a campaign to warn residents in older neighbourhoods that their houses could be connected to the water system by lead pipes. The plan comes after one Charlottetown family found lead levels 80 times the acceptable limit in their drinking water. Starting next month, Charlottetown will be sending out information on lead in April’s utility bill. But the city says it simply can’t afford to replace all lead pipes. It recommends that if people have concerns, they should take other precautions, such as buying a water filter or running the water for a few minutes first thing in the morning before they drink it.”