Aluminum in Drinking Water—Everything You Need to Know

Aluminum in drinking water is more common than you think. A lightweight and versatile metal, aluminum is even used in some water purification systems. But is water with trace levels of aluminum safe to drink? 

In our ultimate contaminant guide below, you’ll learn all about aluminum’s uses and potential toxicity. You’ll also learn how to test your water for aluminum and how to treat it.

Table of Contents:

• How Does Aluminum Get Into Water Sources? 
• Is Aluminum in Drinking Water Harmful?
• How Much Aluminum is Safe in Drinking Water?
• Are There Any Regulations for Aluminum in Drinking Water?
• How Can You Tell if Aluminum Is in Drinking Water?
• Do Water Filters Remove Aluminum?
• How Do You Test For Aluminum in Drinking Water?
• What's the Takeaway?

How Does Aluminum Get Into Water Sources?

Aluminum typically enters water sources two ways: through treatment at the purification plant or through leaching from industrial runoff, consumer products, rainwater, soil, and rock. 

Treatment

Some municipal water treatment operators that source their water from lakes or reservoirs commonly use a process called coagulation to remove turbidity and contaminants that are resistant to most types of disinfection, including chlorination.[1] These contaminants include parasitic microbes such as Giardia and Cryptosporidium.

Coagulation relies on aluminum sulfate, or alum, to bunch smaller particles (0.001 to 10 microns) together into larger particles (>10 microns) which can then be removed by settling or filtration. 

Coagulation is an important step in effective water treatment and—when done properly—should leave a negligible amount of residual aluminum.

Leaching

Aluminum can also make its way into water through leaching, or seeping, into groundwaters and surface waters.  

• Aluminum-rich waste from coal-fired power plants and incinerators can contaminate groundwater with high levels of aluminum. 

• Aluminum is a common ingredient in many consumer goods, including cosmetics, food additives, and cookware. Left to degrade in the environment or in landfills, this waste can leach aluminum into groundwater supplies.

• Aluminum can also leach into groundwater supplies naturally, from soil and rock, from rainwater, or from aluminum dust that settles on surface water. 

Do Aluminum Water Bottles Leach Into Your Water?

No, aluminum bottles won’t leach into your drinking water. As long as you keep your liquid contents within a pH range of 4.0 to 10.0, leaching of aluminum into your drinking water should not occur. Here are a few things to avoid:

• Acidic juices and colas, which can promote leaching

• Dishwashers, which typically use very alkaline (high pH) detergents and could promote leaching.

• Epoxy/Bisphenol-A (BPA)-lined aluminum water bottles, which can leach BPA, a chemical known to be harmful to human health

Is Aluminum in Drinking Water Harmful?

According to current research, aluminum at low levels is unlikely to be harmful to your health. Nevertheless, studies link high levels of aluminum in areas of the human brain and nervous system with neurodegenerative diseases such as:

• Parkinson’s disease
• Lou Gehrig’s disease (ALS)
• Alzheimer’s disease

What Do We Know?

The exact relationship between aluminum and our bodies is not fully understood. Regardless, aluminum is technically a non-essential metal (NEM), which means it poses a potential risk to human health. 

Studies have not confirmed whether or not the presence of aluminum itself causes the diseases listed above, or if these diseases accelerate the presence of aluminum in patients’ bodies.[2] 

The World Health Organization (WHO)’s guidelines state that aluminum has no immediate toxic effects at low levels, but that the relationship between elevated levels of aluminum in drinking water and Alzheimer’s disease should not be dismissed. The WHO also notes, however, that these studies are missing information on other factors that might be affecting their results (including sources of aluminum intake).[3]

Read more about aluminum and Alzheimer’s disease.

When Does Aluminum Become Toxic?

Acute exposure to high levels of aluminum has been known to cause nausea, vomiting, diarrhea, and mouth ulcers among other undesirable effects.

Aluminum toxicity occurs far more commonly through breathing it in (from aluminum dust or fumes in industrial settings) or eating it (from overconsumption of antacids containing aluminum hydroxide, among other aluminum-containing food products).

It is estimated that drinking water makes up only ~4% of our aluminum intake.[3] 

What About Cancer? Bioaccumulation?

Whether or not long-term effects follow acute overexposure in humans is still unknown. But studies have not shown any conclusive evidence linking aluminum and cancer in humans. 

Furthermore, aluminum is not known to bioaccumulate in humans. Aluminum is processed through the kidneys and excreted through urine. So for those with impaired kidney function (or on dialysis), aluminum exposure can pose an increased risk.

Note: An individual’s reaction to chemicals depends on a variety of factors including health, heredity, previous exposure, and personal habits (like tobacco and alcohol consumption).

How Much Aluminum is Safe in Drinking Water?

There is no clear answer to the question of how much aluminum is safe in drinking water.

There are no federal regulations in the U.S. that limit aluminum concentrations based on health effects in municipal drinking water. Federal regulations based on health impacts can give us an idea of how much of a contaminant is safe in drinking water, although those regulations are often a bit higher than pure health-based limits.

California Environmental Protection Agency's Office of Environmental Health Hazard Assessment (OEHHA) calculates health-based guidelines for various contaminants called public health goals (PHGs). PHGs are very conservative and are typically calculated based on levels that prevent potential health impacts over a lifetime of consumption. The PHG for aluminum is 0.6 PPM (parts per million).[4]

However, the chemistry of aluminum in your body is complex and different aluminum compounds are absorbed to different degrees. The PHG was calculated using a dissolved aluminum compound and is very conservative by default.

Are There Any Regulations for Aluminum in Drinking Water?

All in all, it’s difficult to determine a “safe” level of aluminum in drinking water and there are many factors that impact how aluminum can impact your health.

The U.S. Environmental Protection Agency (EPA) has set a Secondary Maximum Contaminant Level (SMCL) of 0.05-0.2 PPM for aluminum in drinking water. 

The EPA’s National Secondary Drinking Water Regulations (NSDWRs) are non-mandatory water quality guidelines meant to prevent off-putting cosmetic or aesthetic effects, like unpleasant tastes, odors, or colors.[5]

The Food and Drug Administration (FDA) has set a regulatory limit for aluminum in bottled water of 0.2 PPM, following the EPA’s SMCL. This limit is also protective against cosmetic and aesthetic effects, it is not a health-based guideline.[6]

Aluminum Limits:

• FDA — 0.2 PPM for bottled water
• EPA’s SMCL — 0.05 - 0.2 PPM for municipal drinking water (non-mandatory)

Secondary versus Primary Drinking Water Regulations

How Can You Tell if Aluminum Is in Drinking Water?

Aluminum has no noticeable taste or odor in water. 

However, at levels above 0.2 PPM aluminum can sometimes make water hazy or turn a bluish color. 

Aluminum’s SMCL is set to prevent any color change in water. There are no at-home/do-it-yourself test kits that can test for aluminum specifically. The only way to know the precise amount of aluminum in your drinking water is by lab testing it. 

Do Water Filters Remove Aluminum?

Yes, but the type of filter depends on your water quality.

At acidic (low) and alkaline (high) pHs, aluminum is more likely to be dissolved than solid. It may also be dissolved at neutral pH if certain conditions aren’t optimized when aluminum-based coagulants are used at the treatment plant.

If aluminum is dissolved, reverse osmosis (RO) may be effective in reducing aluminum concentrations in your water. However it would be important to speak with a filtration expert to make sure RO would work with your specific water quality.

RO is a very popular treatment method that removes a wide range of contaminants—including certain heavy metals, chemicals, and pathogens—by squeezing water through an extremely fine (<0.001 micron), semi-permeable membrane. 

It’s worth noting that RO systems are expensive to install, costly to maintain and create a lot of wastewater. In addition, RO removes many desirable elements, like calcium and magnesium, and typically reduces the pH of your water so it requires post-treatment.. 

At a neutral pH, aluminum is more likely to be solid and, in that case, could be removed by membrane filters with pores larger than those of reverse osmosis membranes, like treatment systems using microfiltration or ultrafiltration. These systems are less expensive and use less water than RO units. Again, though, it is possible for aluminum to be dissolved at neutral pH so it’s not necessarily a simple fix.

Aluminum chemistry is complex so it’s very important to know and understand your water’s unique chemistry and contaminant profile before installing a treatment system. And for aluminum, it may also be necessary to discuss your specific water source and water quality results with a professional before making a treatment decision.

The first step is knowing if aluminum is present in your water!

Testing your water gives you the power to make informed decisions about how to treat your water. 

How Do You Test For Aluminum In Drinking Water?

Certified laboratory testing is the best way to test for aluminum in your drinking water. DIY kits aren’t a good choice if you’re looking for contaminant range or accuracy. They are limited by design in what they can accurately detect.

Lab tests are designed to present the most accurate picture of your water’s contaminant profile, along with insights into a whole range of related matters.

Tap Score Testing Options for Aluminum

What's the Takeaway?

• There is no clear answer to the question of how much aluminum is safe in drinking water and there are no federal regulations to limit aluminum concentrations based on health effects in municipal drinking water. According to current research, aluminum at low levels is unlikely to harm your health.
• Aluminum has no noticeable taste or odor in water. However, at levels above 0.2 PPM aluminum can sometimes make water hazy or turn a bluish color. 
• Testing your water gives you the power to make informed decisions about how to treat your water and certified lab testing is the best way to test your drinking water for aluminum