Lead contamination is widespread and difficult to diagnose, posing serious health risks that can affect both children and adults.
In this guide, we'll delve into the reasons behind lead contamination, explore its health implications, and most importantly, provide you with effective solutions to ensure your water is safe.
Whether you're a concerned parent, a homeowner, or simply someone who values health, this guide is your go-to resource for making informed decisions about water quality.
How Does Lead Enter the Water Supply?
Lead can enter the water supply through various pathways, each posing its own set of risks and challenges for mitigation.
One of the primary sources of lead contamination in drinking water is aging infrastructure, particularly lead pipes, fittings, and solder used in plumbing systems.
Pre-2014, plumbing fixtures could contain as much as 8% lead and still be labelled as "lead-free". These days "lead-free" fixtures can now, "only contain 0.25% lead and this is "a weighted average of 0.25 percent of the wetted surfaces of pipes, fittings, and fixtures" (source).
When water flows through these components, the corrosive elements in the water can cause lead to leach into the supply. This is especially true in areas with acidic or soft water, which can accelerate the corrosion process (U.S. Environmental Protection Agency).
This poses a real problem as water can be contaminated with lead once it has left the water treatment plant. If the neighborhood water pipes are old, they could be a source of contamination, and if your household plumbing is old, it could be a risk too.
Therefore, Consumer Confidence Reports (CCR) that detail the quality of your local municipal water may not be reliable when it comes to the presence of lead in your household water.
This means it's really important that you test your water at the point of use i.e. your faucet. I'll explain how to do this shortly.
Another significant source of lead contamination is from industrial activities, such as mining, smelting, and manufacturing, where lead is used or produced.
Waste and runoff from these activities can contaminate local water bodies and, eventually, drinking water sources. The risk is higher in regions with lax environmental regulations or inadequate waste management systems (World Health Organization).
In some cases, natural geological formations containing lead can be a source of contamination. Areas with natural deposits of lead can experience leaching into groundwater, particularly in regions with acidic soils (Agency for Toxic Substances and Disease Registry).
How Do I Know If There's Lead in My Drinking Water?
Determining the presence of lead in your drinking water is a critical concern, especially if you live in an older home or in an area with known lead contamination issues.
While lead is not visible to the naked eye in water, there are several methods to assess its presence. Some are more reliable than others.
Certified Laboratory Testing - Essential Step
The only truly reliable way to determine if there's lead in your water is through professional laboratory testing.
This tests the water at the point of use (your faucet) so it incorporates the effect of your household plumbing system.
Many labs provide kits that allow you to collect a water sample from your home. You then send the sample back to the lab for analysis. The results will not only confirm the presence of lead but also quantify its concentration, providing a comprehensive understanding of the safety of your water supply. This method is highly recommended for its accuracy and is often considered the gold standard for water testing.
The EPA lists certified local laboratories that can do this for you here.
You can also use dedicated online services such as Tap Score which use EPA-approved laboratory tests.
These services can be expensive but they have quick turnarounds and the online reporting is very easy to understand, which is not always the case with lab reports.
They do 3 tests that identify the presence and concentration of lead in water:
CCR Report - Not Definitive
I mentioned CCR reports and the problem with them when it comes to lead earlier.
Basically, their testing is done at the water treatment plant and doesn't take into consideration any lead contamination that may occur as your water travels through water pipes and fixtures on its way to your faucet.
Therefore, if they report no presence of lead, that is no guarantee that the same can be said for the water in your home. However, if they do report that lead is present then that's a problem for you too.
Your local water utility's annual Consumer Confidence Report is mandated by the Environmental Protection Agency in the United States and provides information on the quality of your community's drinking water, including lead levels.
You can read yours here.
Assess Your Plumbing - Not Definitive
Since the primary cause of lead contamination of drinking water is leaching from water pipes and plumbing fixtures, it makes sense to do an inspection.
One of the initial steps you can take is to visually inspect your water and plumbing. If you notice signs of corrosion, such as rust coloration or reduced water pressure, it could be an indicator of potential lead contamination.
Water that is more corrosive than normal is usually the culprit for this. Water may become more corrosive due to a low pH (it's too acidic) or if it's too soft (it lacks minerals like calcium and magnesium).
If water corrodes pipes that contain lead then the lead will leach into the water.
However, water does not need to have higher than normal corrosivity for leaching to occur. When any water touches a surface then some of that material may dissolve in the water. If there's lead in the pipes, then you have a problem and it might not be visible.
This resource is useful for identifying plumbing fixtures.
It's important to note that visual inspection alone is not a definitive method for detecting lead.
A better option is to hire a licensed plumber who can inspect your home's plumbing system to identify any lead pipes, fixtures, or solder. They can provide expert recommendations on mitigating the risks associated with these components.
Local health departments often offer resources and sometimes even free or low-cost testing services for lead in drinking water. They can guide you through the testing process and help you interpret the results.
Investigate Your Local Service Line - Not Definitive
A service line is the public water system that supplies water to your property. The mains lines typically run under the street and then service lines run off to each individual property on the street.
Millions of properties are still thought to be supplied by lead service lines, so it's important to find out for yourself.
Finding out to how identify lead in your service line is beyond the scope of this article and deserves a guide on its own. Thankfully, this guide is a great resource for finding out exactly how to do that.
The only way to definitively know if there is lead in your water is to test it using the services of a certified laboratory.
Following a positive test, the investigative work begins. How did lead enter your water supply?
Assess your plumbing pipes and fixtures, check your service line, and read your local CCR.
How Much Lead is Safe in Drinking Water?
The question of how much lead is "safe" in drinking water is a matter of ongoing debate among scientists, public health experts, and regulatory agencies.
The U.S. Environmental Protection Agency (EPA) has set an action level for lead in drinking water at 15 parts per billion (ppb). This means that if lead concentrations exceed this level in more than 10% of customer taps sampled, the water system must undertake additional actions to control corrosion (U.S. Environmental Protection Agency).
However, it's important to note that the EPA and the Centers for Disease Control and Prevention (CDC) agree that there is no known safe level of lead exposure.
Even low levels of lead exposure have been linked to cognitive impairment, developmental delays, and other adverse health effects, particularly in children (Centers for Disease Control and Prevention).
Internationally, the World Health Organization (WHO) has set a provisional guideline value of 10 ppb for lead in drinking water. This guideline is based on the achievability of this level using current treatment technology and the associated health risks ( World Health Organization).
The EU and the UK both have their actionable threshold set at 10 ppb too. The EU will reduce this to 5 ppb by 2025.
Canada has recently lowered their lead action level from 10 ppb to 5 ppb.
Some states and local jurisdictions in the U.S. have adopted more stringent standards for lead in drinking water.
For example, Michigan revised its Lead and Copper Rule in 2018 to lower the action level for lead to 12 ppb, effective from 2025 (Michigan Department of Environment, Great Lakes, and Energy). In California, their Public Health Goal is just 0.2 ppb of lead.
Governments have various action levels that decide how much lead is too much in our water supply. However, they all agree that any amount of lead in water is probably too much.
Their action levels take into consideration factors like the degree of difficulty and cost of removing contaminants. They're not based solely on health risks like you'd think.
Health Risks Associated with Lead in Drinking Water
Lead exposure through drinking water poses a significant public health concern, affecting various physiological systems in the human body.
The neurological impact of lead exposure is particularly concerning. Children exposed to lead are at risk of developing behavioral issues, lower IQs, and learning disabilities.
Pregnant women are another vulnerable group, as lead exposure can result in premature birth and reduced birth weight. The cardiovascular system is also not spared; adults exposed to lead have a higher risk of developing heart disease and kidney problems.
The World Health Organization (WHO) emphasizes that lead is a priority chemical hazard that should be included in national drinking-water quality standards and monitored as part of drinking-water quality surveillance (WHO Source).
Health Canada's guideline technical document on lead in drinking water reviews and assesses all identified health risks associated with lead exposure.
It states that the maximum acceptable concentration (MAC) for total lead in drinking water is 0.005 mg/L, based on a sample of water taken at the tap.
The document also notes that current science cannot identify a level under which lead is no longer associated with adverse health effects, suggesting that lead concentrations in drinking water should be kept as low as reasonably achievable (Health Canada Source).
How to Remove Lead from Your Drinking Water
So you've identified lead in your drinking water, what next?
The first step should be to perform an audit of your household plumbing fixtures.
"Lead-free" fixtures (containing less than 0.25% lead) can be identified by the NSF/ANSI Standard 372 and NSF/ANSI Standard 61, Annex G.
This reduction in the amount of lead in plumbing fixtures (from 8% to a weighted average of 0.25%) went into effect in January 2014. Therefore, any plumbing work done before then should be inspected.
A certified plumber will be able to tell you more about your household plumbing than you or I can.
But, even after replacing problematic fixtures the issue still remains that your household water may be supplied by a lead service line.
Your next step should then be to install an effective form of water filtration. I'll go through this process in detail in the next section.
Home water treatment is really the last resort. Ideally, with a contaminated water source you want to put a stop to the cause of pollution or find an alternative water source.
However, this is often very difficult or impossible.
Home water treatment then becomes an accessible alternative. But, this is just putting a band-aid on the problem.
How to Choose an Effective Lead Water Filter
There are a variety of different methods of water filtration that target lead.
The two most effective devices available at home are distillers and reverse osmosis water filters.
I'll discuss each method in more detail below, as well as outline how to choose the best water filter for your specific water problem.
Water Distillation - NSF/ANSI 62
Water distillation is a really effective method of removing lead from water. It can remove up to 99.5% of impurities from water when operated properly. It uses evaporation to separate the water into its constituent compounds.
The pure water evaporates with the steam escaping and then cooling and condensing to form filtered water. The heavy metals like lead as well as other inorganic compounds do not evaporate and are left behind.
Distillation is therefore a very effective process for targeting lead specifically. It's also effective at removing other contaminants that have boiling points that are higher than water, such as some pesticides.
However, the limitation with distillation is that any contaminants that boil at a lower temperature than water will evaporate too and vaporize with the water. This means they will be included with your distilled water unless the distiller uses another form of filtration (good water distillers use carbon filtration as well).
A couple of other drawbacks with distillers that you should consider are their reliance on electricity and their relatively slow rate of operation.
A household with more than a couple of people would probably need a more industrial-sized device that can provide more than a couple of gallons of clean water per day. This would likely cost upwards of $1,000. These are large units that require floor space.
Large Countertop Distiller - approx 5 gallons per day - link
Industrial Distiller approx - 10 gallons per day - link
Reverse Osmosis - NSF/ANSI 58
Reverse osmosis is the most effective form of home water filtration. The reverse osmosis membrane alone can remove hundreds of contaminants with a success rate of up to 99%.
Combine this with other forms of water filtration (like carbon) which are usually included in these household systems, then rejection rates of 99.9% for certain contaminants can be achieved.
You'll find certified RO systems that remove more than 99% of lead for example. Here's one of them.
These systems are usually installed under the sink and consist of multiple stages of filtration. The filtered water is stored in a tank (standard size is 4 gallons) ready to be dispensed. The alternative is a tankless countertop system.
The big drawback here is the waste water that is produced during the filtration process. Even with the most efficient models the waste water to clean water ratio is around 1:1, which is very wasteful.
This is the price you have to pay for what is the most thorough home water filter system available.
Cost-wise, you're talking around $150 - $400 dollars depending on the level of filtration and the capacity.
For reverse osmosis water filter systems that are certified to remove lead look for the NSF/ANSI 58 badge. You'll also see 'lead' listed as one of the certified contaminants.
Other certifications exist but this one is certainly the most recognizable.
Other Water Filters - NSF/ANSI 53
When it comes to lead removal, distillation and reverse omosis are certainly the big hitters but they're not the only options open to you.
NSF/ANSI 53 is the certification that concerns the reduction of contaminants like lead and under this banner, you'll find a whole host of water filtration methods.
It's important to note that lead is not the only contaminant listed under NSF/ANSI 53 and when you see this certification you'll also find a list of contaminants that the specific water filter is proven to remove.
You can find a list of NSF/ANSI 53 certified water filters for lead removal here.
The methods of water filtration include:
Water filter pitchers - like a Brita (but not a Brita because they're not very good). Filtered pitchers are inexpensive and portable.
Refrigerator water filters - for filtering the water dispensed by a refrigerator.
Faucet mounted - attaches directly onto your faucet. Inexpensive but not recommended if you have any type of fancy faucet.
Countertop models - usually connects to your existing faucet but some use their own.
Undersink models - installs under the sink and usually uses a special faucet.
How Else Can You Reduce Your Lead Exposure?
Use an alternative source of water - this isn't easy, but a fallback can always be to use bottled water. It's not great for the environment but it's better than drinking unsafe water.
Flush your plumbing - run your faucet for a minute before use. This will help to flush out water that has been sitting in the pipes and possibly corroding them. However, all this does is lower the concentration of lead, it does not remove it.
Never drink from the hot water faucet - hot water is likely to corrode pipes more easily and could contain high concentrations of lead.
Boiling water does not help! - boiling water can help remove viruses and bacteria but it doesn't remove the lead. If anything it probably makes the water more concentrated with lead as some of it is lost as it evaporates but the lead remains. Distillation separates these particles while boiling does not.