Aluminum is a versatile metal used in countless applications, from constructing automotive engines to helping purify drinking water. But is water contaminated with aluminum safe to drink?
Most people are aware that heavy metal contamination can make water extremely unsafe to drink, but aluminum contamination can be a lot more complex. Here you will learn everything you need to know about aluminum in drinking water, how to test for it, and how dangerous it may be.
- The safe levels of aluminum are set at .05 – 0.2 mg/L by the EPA for municipal drinking water and at 0.2 mg/L by the FDA for bottled water.
- Ingesting elevated levels of aluminum in drinking water can lead to human health effects including kidney disease, bone disease, Alzheimer’s disease, and impaired kidney function.
- Aluminum salts are used as a coagulant during the water treatment process to remove parasitic microbes and turbidity. It can also leach into groundwater as water passes through soil, or rocks with high aluminum concentrations.
- The recommended treatment systems to remove aluminum from your water are reverse osmosis and microfiltration, depending on if the aluminum is in a dissolved state or not.
How Does Aluminum Get Into Water Supplies?
Aluminum is the third most common element in the Earth’s crust, meaning it is just about everywhere. Aluminum metal is highly reactive with other elements, and trace quantities of aluminum compounds are present in many rocks, clay, and minerals.
With aluminum metal present in so many applications, it is no wonder that residual aluminum frequently ends up in drinking water. One of these ways is through leaching, in which trace quantities of aluminum can seep into groundwater and surface water from human waste, soil, or rocks with high aluminum concentrations.
This often occurs from landfills as well as from industrial runoff, coal-fired power plants, or mining operations. However, it will occur to some degree regardless of human interaction due to the naturally present aluminum concentration in the environment.
Water Treatment Coagulation
Another way in which aluminum can make its way into drinking water is through the water treatment process. One common method for purifying water is water treatment plants using coagulation with aluminum sulfate (VI). This technique is used to eliminate small contaminants like turbidity and microorganisms that cannot be easily removed through disinfectants such as chlorine.
Coagulation in a drinking water treatment system uses aluminum sulfate to “coagulate” several smaller particles (less than 10 microns) into larger ones (greater than 10 microns) which can then be removed through filtration or settling. Though most aluminum will be recaptured, this process can leave trace amounts of residual aluminum (generally below the EPA’s 0.2 mg/L SMCL), which can end up in drinking water. That is why aluminum may be in your drinking water.
In addition, due to its properties, aluminum compounds are added to many consumer products, including food additives, antiperspirants, and cosmetics, among others. You could find aluminum all around you in your everyday life.
Due to its availability and wide range of applications, aluminum metal is widely used in construction, manufacturing, and other applications. For example, aluminum can leach into water supplies from concrete structures and pipes that frequently contain the heavy metal.
Do Aluminum Water Bottles Leach Into Water?
No, aluminum water bottles do not leach into drinking water. If the liquid contents in the bottle are not too acidic (pH range of 5.0 to 9.0), aluminum will not leach into your drinking water. This applies to highly acidic water, juices, or soda.
What Are The Effects Of Aluminium In Drinking Water?
Aluminum exposure, such as through drinking water, is generally not harmful in small quantities. However, in extremely high concentrations, aluminum toxicity can result in damage to the nervous system. Some symptoms can include:
- Memory Loss
- Speech Disturbances
- Weakened Motor Movements
In addition, some studies have found that exposure to high aluminum concentrations can lead to nervous system damage or neurodegenerative diseases such as Alzheimer’s Disease.
People may be exposed to aluminum through many means, including drinking water, food additives, medicines, cosmetics, deodorants, and more. Again, aluminum is all around you, and thus, exposure can come from everywhere.
Under normal circumstances, food consumption will account for 95% of aluminum intake and water about 1-5% of oral consumption. However, the use of antacids containing aluminum hydroxide can result in many times the amount of exposure.
What Are Safe Levels Of Aluminum In Drinking Water?
There is still a lot of debate on what constitutes a safe level of aluminum in drinking water, and currently, there are no federally enforceable limits for aluminum concentrations in drinking water. However, there are some recommendations and state-level regulations that can help provide guidelines for safety.
The Environmental Protection Agency (EPA) has provided a recommended Secondary Maximum Contaminant Level for aluminum in drinking water of 0.05 – 0.2 mg/L. These secondary drinking water standards are not enforceable, but the U.S. Food And Drug Administration (FDA) has also set a limit for aluminum in bottled water of 0.2 mg/L, which corresponds with this lower limit.
In California, the Office of Environmental Health Hazard Assessment (OEHHA) has also set a public health goal (PHG) for aluminum levels in municipal drinking water. These PHGs are created with the possible effect of exposure to a substance over the course of an individual’s life. As a result, this is a very conservative estimate intended to protect public health, and for aluminum, California’s PHG is 0.6 mg/l.
What Is A Toxic Level Of Aluminum?
Aluminum toxicity occurs from ingesting high amounts of the metal over an extended period of time. Toxicity has been shown to occur at concentrations greater than 100 mg/L but can occur at 60 mg/L or lower with kidney dialysis patients. Symptoms of toxic exposure include vomiting, diarrhea, reduced body weight, and lower hormone levels.
Note that some individuals are at greater risk for aluminum poisoning, including people with impaired kidney function and babies. Since we only get approximately 5% of our daily intake of aluminum through drinking water, it is critical to understand all of your sources of exposure (such as inhaling aluminum dust, touching, or eating aluminum hydroxide).
Observations For Aluminum In Tap Water
Like many contaminants, aluminum has no detectable odor or taste in water. At very high levels exceeding 0.2 mg/L, aluminum can sometimes create a blueish or hazy color in the water.
Since aluminum is regulated as a secondary contaminant, the EPA’s concentration level is set to prevent aesthetic changes in water quality. If you notice any health symptoms or live in an area known to have aluminate sulfate used in the water treatment, it is recommended to test your water.
We are not aware of any DIY test kits for aluminum specifically. Checking your local Water Quality Report is a good first step to identifying the potential for aluminum in your tap water. However, the only method to detect the concentration of aluminum in your drinking water with certainty is to use a certified lab.
How To Test For Aluminum In Drinking Water
In drinking water, aluminum has no discernible taste or odor, meaning it is impossible to know if it is present without testing. Unfortunately, there are no simple at-home tests you can perform to determine how much is present. This leaves one option, which is laboratory testing.
Certified Lab Test
A certified lab test provides the most accurate results to detect the exact levels of aluminum present in your drinking water.
I recommend the Freshnss Labs water test kit that scans for heavy metals including aluminum, lead, copper, and much more. The kit comes with everything needed to properly collect a water sample from your home’s faucets and send it to a certified lab.
Generally, collecting a sample will simply require taking a sample of tap water. You can do this by removing the aerator from a clean faucet, letting it run for several minutes to remove built-up contaminants, and filling the specimen collection cup with tap water to the indicated level.
You will then package the sample according to the instructions and mail it to the laboratory for testing. Within three business days, you will receive a detailed report with the amount of aluminum in your drinking water, any health or plumbing alerts, and the best treatment method based on your test results.
Treatment To Remove Aluminum In Drinking Water
If your drinking water does contain a high concentration of aluminum, it is possible to reduce it in most cases. Many water filtration methods can reduce concentrations of aluminum depending on the pH of your water.
With water that has low acidity (high pH), aluminum is more likely to be dissolved and requires a filtration system with a small micron rating like reverse osmosis.
Reverse osmosis is one of the most effective treatments to remove aluminum from drinking water. Reverse osmosis uses high pressure to force water through layers of semi-permeable membranes with pores that are .0001 microns which trap contaminants, including aluminum compounds.
Reverse osmosis filtration is extremely effective in many cases and can remove up to 99% of aluminum contamination. This can leave tap water clean and safe to drink.
If the aluminum in your water is not in a dissolved state, you can use a filtration system that has a larger pore size like ultrafiltration or microfiltration. These systems are less expensive than ROs and generate less wastewater. However, even if you have a balanced pH, the aluminum may still be dissolved due to the aluminum-based coagulants used at water treatment plants.
Frequently Asked Questions
Is it safe to drink from aluminum bottles and cans?
Yes, aluminum will not leach from cans or bottles under normal conditions because they are coated with a protective polymer. As long as the liquid contents are not highly acidic, you can safely drink from aluminum bottles or cans without risking too much exposure.
Why is aluminum added to drinking water?
Aluminum is added to drinking water treatment for its coagulation properties. In this process, smaller contaminants bond together to make it easier to remove them through filtration or settling.
How much aluminum is toxic to ingest?
There is still heavy debate on the amount of aluminum that can be harmful over an extended period. However, studies have found that aluminum toxicity occurs at blood concentrations higher than 100 micrograms per liter.