How to Address Lead Contamination in Water

How to Address Lead Contamination in Water

Lead contamination in drinking water poses serious health risks. Its initial symptoms are often mild or imperceptible, making it easy to overlook. However, the long-term consequences are severe and irreversible.

Recall Global News' investigative report revealing widespread lead contamination in tap water across Canada—from homes to schools—sparking public alarm that continues to this day.

This critical finding emerged from a year-long investigation by over 120 journalists from nine universities and ten media organizations, including Global News and Concordia University's Institute for Investigative Journalism. Typically, water leaving municipal treatment plants is lead-free, indicating that the primary source of contamination is lead-containing pipes and solder in the distribution network. Most Canadian cities acknowledge that some of the hundreds of thousands of underground pipes may not be replaced for decades. Additionally, these municipalities report that coordinating replacements is challenging because homeowners would bear the cost for their own pipes—a burden many are unwilling to shoulder. Journalists compiled lead content test results from 11 cities. Since 2014, one-third (33%) of 12,000 tests conducted across these cities exceeded the national safety standard of 5 parts per million (ppm).

The latest international consensus holds that lead toxicity has no safe threshold—it should never be present in drinking water or food. Even low concentrations of lead can cause serious health damage. Risks for adults include hypertension, kidney damage, and gout.

Numerous international studies support this. For example, Danish scholar Moller tracked blood lead levels in 1,052 Copenhagen adults. After adjusting for various confounding factors, he found that blood lead levels could predict mortality. Higher blood lead levels correlated with increased mortality rates. Blood lead levels are linked to hypertension, coronary artery disease, and cardiovascular disease. Children exposed to even low levels of lead face risks of low birth weight, growth retardation, and impaired IQ and cognitive abilities.

Lead is ubiquitous in the environment, with tap water being a significant source. Critically, lead in water is more readily absorbed by the body. In Ontario, publicly available government data reveals 919 instances of lead exceeding standards over the past two years—exceeding one-fifth of federal requirements for lead testing in tap water. In some cities, the exceedance rate reached 50%. In London, half of 36 tests conducted last year exceeded standards. Windsor recorded the highest number of tests at 289, accounting for a quarter of all tests over the past two years. In the town of Thresher Bay on the north shore of Lake Superior, the probability of test results exceeding national standards approached 21%. Before a comprehensive replacement of lead pipes, how can you protect the drinking water in your home?

I. Primary Sources of Lead in Drinking Water

The first source stems from industrial pollutants and unregulated wastewater discharge (primarily from smelting, mining, chemical, and textile industries) alongside widespread agricultural pesticide use, causing severe water contamination.

The second and primary source is lead leaching from corroded municipal water distribution pipes—the main cause of lead-related health hazards in drinking water.

Additionally, lead can leach from welded joints in all piping systems, as well as from household plumbing fixtures made of chrome-plated or brass materials. Consequently, even if tap water meets national standards when leaving the treatment plant, its lead content may exceed these standards by the time it reaches household faucets after traveling through extensive distribution networks.

II. The Hidden Threat to Children

Modern medicine confirms that lead primarily damages the nervous system, posing the greatest risk to children under six years old, whose blood, nerves, and brain tissue are most vulnerable to toxicity.

The World Health Organization identifies lead as one of thirteen factors harmful to children's health. Lead is a neurotoxic heavy metal with no physiological function in the human body, yet it is ubiquitous in the environment. Due to their metabolic and developmental characteristics, children are particularly sensitive to lead toxicity.

III. Four Recommendations:

1. When tap water has been unused for over six hours, always flush the faucet for two to three minutes before use. Lead levels in stagnant water within pipes can be extremely high. Poor-quality faucets may also leach heavy metals into the water. Opt for stainless steel, lead-free faucets to mitigate this risk. Additionally, hot water flowing through pipes can release more heavy metals, so avoid drinking water from hot water lines. Drain 1-2 Minutes of Stagnant Water in the Morning The water flowing in the morning is water that has been sitting in the pipes overnight. Therefore, any lead or other heavy metals dissolved from the pipes are present in this water, making it the worst water quality of the day.

Experts recommend letting the tap run for 1-2 minutes after waking up. Save this water for laundry or mopping, but do not drink it.

2. While many households now have hot water supply, it is best not to use it for drinking or cooking. The lead content in hot water is significantly higher than in cold water.

3. Households with the means should consider installing a home water purifier (using reverse osmosis technology). Its multi-stage filtration effectively removes lead, ensuring safe drinking water. When evaluating a purifier's performance, prioritize the quality of its filter cartridges. These cartridges act as the “guardians” of tap water, determining which substances pass through and which are blocked.

1. Activated Carbon Like a building manager, activated carbon filters restrict certain suspicious “visitors”—pesticides, trihalomethanes, odors—but show limited effectiveness against nitrates, hardness, and heavy metals.

2. Reverse Osmosis (RO) Water Purifiers Like royal guards with multiple layers of defense, RO systems feature 3 to 5 filtration stages, offering the most comprehensive contaminant removal among water purifiers. Consequently, reverse osmosis systems are cost-effective and relatively low-maintenance (typically lasting 4-5 years). Their membranes feature finer pore sizes, filtering out more impurities and effectively removing heavy metals like lead, copper, and cadmium. Note: Treated softened water must not be connected to other plumbing lines, as it may leach heavy metals again.

4. After boiling, simmer for 3 minutes

After bringing tap water to a boil, uncover the pot and simmer on low heat for about 3 minutes. This allows trihalomethanes to evaporate. Ensure the exhaust fan is running to prevent volatilized pollutants from spreading throughout the kitchen. Water dispensers achieve similar results to boiling.

In summary, while lead in drinking water exists in trace amounts, long-term consumption allows lead to accumulate in the body. This accumulated lead is difficult to expel and poses serious health risks. For the sake of children's health, please pay attention to lead contamination in drinking water.

First Step: Replace the Faucet

To drink a glass of good water, we all share the responsibility.