Lead's Watery Poison: How Does Lead Pollute Water Sources?

Lead is a toxic heavy metal that is extremely harmful to human health, especially to infants, young children, and pregnant women. There is no safe level of exposure to lead, and it can enter the body through inhalation or ingestion. Lead can contaminate water supplies through old plumbing systems, pipes, and fittings, leaching into the water and causing serious and irreversible damage to the body. Lead poisoning can affect multiple organs, including the brain, liver, kidneys, and bones, and can cause long-term harm such as increased risk of high blood pressure, cardiovascular problems, and kidney damage. Young children are particularly vulnerable as they absorb more lead than adults, and the toxic effects can lead to permanent adverse health impacts on their central nervous system.

Lead in plumbing systems, pipes, and fittings

In 2014, the term "lead-free" was redefined to include only fixtures with a lead content of 0.25%. Newly installed fixtures must use "lead-free" materials, but this does not apply to older fixtures that are still in use. On September 1, 2020, the US Environmental Protection Agency (EPA) published the final regulation, "Use of Lead Free Pipes, Fittings, Fixtures, Solder, and Flux for Drinking Water." This rule requires manufacturers and/or importers to certify that their products meet the requirements using a consistent verification process within three years of the final rule publication date.

The primary route for lead poisoning in drinking water is not old or historic contamination of the aquifer but the distribution system and plumbing within the home. Lead particles can collect in the aerator of your faucet, and if they are not cleaned out, they can get into your water. The longer water sits in pipes, the more lead it may contain. This is why it is recommended to run your tap for a short time before using the water for drinking or cooking.

To determine if your home has lead pipes, you can check the service line that connects your home to the water main. Lead pipes tend to have a dull grey colour, can be scratched with a key, and a magnet will not stick to them. If you are unsure, you can contact your water utility or a licensed plumber for assistance. It is important to be aware of any nearby construction or maintenance work that could disturb the line, as this can cause more lead to be released into the water.

Sources of lead exposure

Lead in Drinking Water

Drinking water is a common source of lead exposure, especially for children, who can absorb more lead than adults. Lead can enter drinking water through plumbing systems containing lead pipes, faucets, fixtures, fittings, and solders. In homes with lead pipes, these pipes are typically the most significant source of lead in the water. Lead particles can also collect in the aerator of a faucet, which is the screen that filters the water. The longer water sits in pipes, the more lead it may contain, so it is recommended to run the tap for a short period before using the water for drinking or cooking.

Lead in Paint

Lead-based paints were historically used in homes, children's toys, and furniture. Although lead-based paint has been banned in the United States since 1978, it still remains on walls and woodwork in many older homes and apartments. Children are particularly vulnerable to lead exposure from paint, as they may ingest paint chips or put their hands in their mouths after touching contaminated surfaces.

Lead in Soil and Dust

Lead particles from sources such as leaded gasoline or paint can settle on soil and last for years, contaminating the surrounding area. This is especially common near highways and in urban settings. Lead-contaminated soil can be tracked into homes, where it contributes to household dust. Young children are at an increased risk of exposure to lead-contaminated dust and soil due to their tendency to put objects and their hands in their mouths.

Other Sources

Other sources of lead exposure include mining, smelting, manufacturing, recycling activities, and the use of lead in various products such as batteries, pigments, solder, ammunition, ceramic glazes, jewellery, and toys. Lead can also be inhaled through airborne particulates or ingested through contaminated food.

Testing for lead in water

Lead is a toxic heavy metal that can enter drinking water through plumbing systems containing lead pipes, solders, and fittings. It is harmful to human health, especially to young children, and there is no safe level for lead exposure. The degree of exposure depends on the concentration of lead, route of exposure, current medical condition, and age of the individual. Lead in drinking water can be attributed to up to 20% of the total lead exposure in children.

Identify Potential Sources of Lead

Before testing the water, it is crucial to identify potential sources of lead in your home. Check if the service line (the pipe connecting your home to the water main) is made of lead. You can do this by contacting your water utility company or a licensed plumber. Plumbing fixtures, welding solder, and pipe fittings made before 1986 may also contain lead. Additionally, lead particles can collect in your faucet's aerator, so regular cleaning is essential.

Contact Local Water Authority or Certified Laboratories

Your local water authority is the first source for testing and identifying lead contamination in your tap water. Many public water authorities have websites that provide data on water quality, including lead testing results. Alternatively, you can contact certified laboratories to test your water samples. These laboratories are equipped to analyze lead levels in water and provide accurate results.

Collect Water Samples

If you opt for laboratory testing, carefully follow the directions provided by the certified laboratory for collecting water samples. Collect the samples from faucets where you usually drink or use water for cooking. The sampling method and time of day can impact the test results, so ensure you follow the laboratory's instructions precisely.

Testing Costs and Programs

The cost of testing for lead in water can vary depending on the laboratory and your location. In some cases, testing can range from \$15 to \$100. Additionally, some states or utilities offer programs to assist with the cost of water testing and lead service line replacement for residents. Contact your state or local water company to inquire about such programs and for more information on testing procedures.

Reducing Lead Exposure

While testing is essential, it is also crucial to take proactive measures to reduce lead exposure. Always use cold water for drinking, cooking, and making baby formula, as boiling water does not remove lead. Running your water before use can help flush out any lead that may have accumulated in the pipes. If lead is detected, consider using a "point-of-use" filter certified for lead removal by an independent testing organization.

Health Consultation

If you suspect lead exposure, especially for children, consult a healthcare provider. They can determine the need for a blood lead test and recommend appropriate follow-up actions. Lead exposure can have serious health consequences, and it is essential to take proactive measures to protect yourself and your family.

Reducing lead exposure

Lead is a naturally occurring element found in the Earth's crust. It is a toxic heavy metal that is harmful to human health, especially to young children and women of child-bearing age. There is no safe level of exposure to lead, and it can cause serious and irreversible damage to the body, including the nervous system, fertility, and cognitive ability. Lead can enter drinking water through plumbing systems containing lead pipes, faucets, solder, and fittings. Older homes, built before the 1980s, are more likely to have lead plumbing.

To reduce lead exposure, it is important to identify the source of lead in your water. You can do this by contacting your local water utility or a licensed plumber to determine if your home has a lead service line. If your home does have a lead service line, you should be aware of any nearby construction or maintenance work that could disturb the line and release more lead into the water. It is recommended to have your water tested by contacting your water utility or a certified laboratory to learn about the lead levels in your drinking water.

Once you have identified the source of lead, there are several ways to reduce exposure:

• Use only cold water for drinking, cooking, and making baby formula. Warm or hot water is more likely to contain higher levels of lead.
• Run your water before use. The longer water sits in pipes, the more lead it may contain. Flush your pipes by running the tap, taking a shower, doing laundry, or doing the dishes.
• Clean your faucet's aerator regularly. Sediment, debris, and lead particles can collect in the aerator, and lead can get into your water if these particles are not removed.
• Use a certified water filter. Install a "point-of-use" filter certified by an independent testing organization, such as the Water Quality Association (WQA) or NSF International, to reduce lead in drinking water.
• Consider bottled water. Drinking or using only bottled water that has been certified by an independent testing organization can virtually eliminate lead exposure, although this may not be a cost-effective long-term solution.

Health effects of lead poisoning

Lead is a naturally occurring toxic metal found in the Earth's crust. It is heavy and soft, with a low melting point. It is harmful to human health, and there is no safe level for lead exposure. The degree of exposure depends on the concentration of lead, route of exposure (air, water, food), current medical condition, and age of the individual.

Once lead enters the body, it is distributed to organs, including the brain, kidneys, liver, and bones. It is stored in the teeth and bones, where it accumulates over time. Lead stored in bone may be released into the blood during pregnancy and expose the fetus. Malnourished children are more susceptible to lead as they absorb more if other nutrients are deficient, especially calcium or iron.

Children are at a particularly high risk of lead poisoning. They may absorb up to 4–5 times as much lead as adults from an ingested dose. Their innate curiosity and frequent hand-to-mouth behaviours increase their risk of exposure to lead-contaminated dust, soil, and paint. Children who engage in pica, the compulsive consumption of non-food items, are at an even higher risk.

In children, lead exposure can cause permanent adverse health impacts, particularly on the development of the central nervous system. It can also result in a spectrum of injuries across multiple body systems. Exposure to very high levels of lead can cause severe damage to the brain and central nervous system, causing coma, convulsions, and even death. Children who survive severe lead poisoning may be left with permanent intellectual disabilities and behavioural disorders.

In adults, lead exposure can cause long-term harm, including an increased risk of high blood pressure, cardiovascular problems, and kidney damage. Lead was attributed to more than 1.5 million deaths globally in 2021, primarily due to cardiovascular effects.

Frequently asked questions