LEAD IN DRINKING WATER FACT SHEET
What is Lead?
Lead is a toxic metal found in natural deposits. It can be found in air, soil, dust, food, and water. Lead was commonly used in household plumbing materials and water service lines until 1986. The National Plumbing Code allowed lead as an acceptable material for pipes until 1975 and in solder until 1986. All provinces and territories use the National Plumbing Code as a basis for their own regulations. Regulations regarding lead used in plumbing materials were phased in across the country. Therefore, the timing of when lead service lines and other lead-based plumbing materials stopped being used may differ depending on where you live.
The Dangers of Lead in Drinking Water
Children ages six and under are at the greatest risk. Pregnant women and nursing mothers should avoid exposure to lead to protect their children. Lead can cross the placenta during pregnancy to affect the unborn child, and can be released into breast milk. Potential effects include premature births, smaller babies, decreased mental ability in the infant, learning difficulties, and reduced growth in young children. Lead exposure is most serious for young children because they absorb lead more easily than adults and are more susceptible to its harmful effects. Even low level exposure may harm the intellectual development, behaviour, size, and hearing of infants.
In babies and children, exposure to lead in drinking water above 0.015 mg/L (the Guideline for Canadian Drinking Water Quality maximum acceptable concentration for lead is 0.01 mg/L) 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. Adults who drink this water over many years could develop kidney problems, anemia, reduced sperm count and fertility problems, and high blood pressure. There is a future risk of osteoporosis in exposed children. Symptoms of adverse effects to the nervous system, the primary target organ for lead, include forgetfulness, tiredness, headaches, changes in mood and behaviour, lower IQ, decreased hand dexterity and weakness of arms, legs, wrists, fingers or ankles.
In addition to these health effects, people who are exposed to moderate levels of lead for an extended period of time may be at a greater risk of experiencing changes in hearing ability, digestive issues (abdominal pain, cramps, nausea, vomiting, etc.), altered immune systems and changes in levels of certain hormones.
Exposure to lead over a lifetime may also increase the risk of developing cancer. The International Agency for Research on Cancer (IARC) has recently re-classified lead as probably carcinogenic to humans (Group 2A), based on sufficient evidence of carcinogenicity in experimental animals and some limited evidence of carcinogenicity in human studies.
Lead is rarely found in source water, but enters tap water through corrosion of plumbing materials. Homes built before 1986 are more likely to have lead pipes, fixtures and solder. The most common problem is with brass or chrome-plated brass faucets and fixtures which can leach significant amounts of lead into the water, especially hot water.
What Should You Do?
Boiling your water will not get rid of lead. If you suspect that your water contains high lead levels you should have your water tested. Some municipalities have an established sampling program while others may do it upon request. In some cases, you may have to arrange for your own sampling and analysis by an accredited laboratory. You should be particularly suspicious if your home has lead pipes (lead is a dull gray metal that is soft enough to be easily scratched with a house key) or if you see signs of corrosion (frequent leaks, rust-coloured water). Lead-based pipes and other plumbing materials are more likely to corrode if the water has a low pH (is very acidic) or if the alkalinity (the ability of the water to stabilize the pH) is too low. Testing is the only way to confirm if lead is present or absent. Most water systems test for lead as a regular part of water monitoring. Testing is especially important in high-rise buildings where flushing might not work. These tests give a system-wide picture and do not reflect conditions at a specific drinking water outlet. Your water supplier may have useful information, including whether the service connector used in your home or area is made of lead. In most communities, the municipality or water utility is only responsible for the service line up to the curb. The portion of the service line from the curb to the house falls under the responsibility of the homeowner, but the municipality may be able to tell you whether it is made of lead. If your water comes from a household well, check with your health department or local water systems that use ground water for information on contaminants of concern in your area.
Children at risk of exposure to lead should be tested. Your doctor can perform a simple blood test to determine your child’s blood-lead level. If your child has a blood lead level at or above 10 ug/dl, you should take preventive measures.
The following are some tips to reduce your family’s exposure to lead:
1. Use cold water for drinking or cooking. Never cook or mix infant formula using hot water from the tap.
2. Make it a practice to run the water at each tap before use.
3. Do not consume water that has sat in your home’s plumbing for more than six hours. First, make sure to run the water until you feel the temperature change before cooking, drinking, or brushing your teeth, unless otherwise instructed by your utility. This could take as little as five to thirty seconds if there has been recent heavy water use such as showering or toilet flushing. Otherwise, it could take two minutes or longer. Your water utility will inform you if longer flushing times are needed to respond to local conditions.
4. Some faucet and pitcher filters can remove lead from drinking water. If you use a filter, be sure you get one that is certified to remove lead by NSF International. There are also reverse osmosis and distillation treatment devices which can be purchased. For best results, these filters and devices should be installed at the tap that is most commonly used for drinking water, in most cases the kitchen tap.
To permanently address any lead issues with your drinking water, you can remove some of the sources of lead that are entering your water. The municipality is responsible for the main service lines; the homeowner is responsible for the service lines from the curbs to their homes. Therefore, if the portion of the lead service line from the curb to your house is lead-based, you would be responsible for its replacement. Some municipalities that are replacing the main service lines have also established programs where residents can replace their portion of the service line at the same time for a reduced cost. Contact your municipality to find out whether such a program exists in your community. In some cities it is now required that both the main service line and the residents’ portion of the service line be replaced at the same time. For example, in the past when the City of Saskatoon was replacing its portion of the water line, the homeowner had the option to replace their portion of the water connection at a shared cost. An advisory was issued by the American Water Works Association in February 2010, indicating that disturbing and replacing the street portion of a service connection can cause lead levels in the waterline to substantially increase for a period of time. It also advised that if the remainder of the lead connection from the property line to the house is left intact, lead levels can continue to be elevated longer. Due to these health and safety concerns, if a lead water line is being replaced, the City of Saskatoon requires that the entire line be replaced from the water main to the water meter inside a home. The City of Saskatoon will cost share the line replacement with the homeowner, with the homeowner’s share being added to their property tax bill. The homeowner is also responsible for the piping costs within the house from the house footing to the water meter. If you live in a city where it is possible for only a portion of the lead service line to be replaced, there may still be a lead issue in the future. In addition, some lead particles may detach from the remaining lead pipe for two to three months due to disruption from the change. As a result, it is important to monitor the lead levels during this time, or to use a treatment device for that same period. You can also have any pipes, fittings or faucets in your home containing lead replaced with the appropriate materials certified for contact with drinking water. To avoid any future problems, avoid the use of lead solder and only use plumbing materials, such as piping, certified specifically for use in contact with drinking water for your household plumbing system.
Environmental Health Perspectives. May 2010. Reaction to the Solution: Lead Exposure Following Partial Service Line Replacement.
Health Canada. 2007. Minimizing Exposure to Lead from Drinking Water Distribution Systems.
United States Environmental Protection Agency. June 3, 2013. Drinking Water Contaminants.