Silver is a sought-after metal that’s most well-known for its use in jewelry. Many of us wear silver on a daily basis – and some of us may also drink trace levels of silver in our water.
Silver is held indefinitely in the body’s tissues, making it one of the most harmful drinking water contaminants if consumed in excess. In this glossary, we’ve answered your most common questions about silver in water, including how it gets there, its health effects, and how to protect your family from this impurity.
Table of Contents
- ❔ What is Silver?
- 🩺 What are the Potential Health Effects of Silver?
- 🚰 How Does Silver Get Into Drinking Water?
- 📉 Do Water Treatment Facilities Monitor Levels of Silver in Drinking Water?
- 🔎 How Can I Tell if Silver is in My Drinking Water?
- 👩🏽⚕️ How Can I Protect My Family from Silver in Drinking Water?
- ⚠️ How Else Can I Be Exposed to Silver?
- 📝 Where Can I Get More Information?
❔ What is Silver?
Silver is a chemical element with the highest reflectivity, thermal conductivity, and electrical conductivity of any metal.
Silver is most valued for its decorative beauty, and is often used to make rings, necklaces, and other jewelry and tableware items. Silvers’ light-reflecting properties make it a popular material in mirrors, although silver is known to tarnish over time. Some batteries, electrical contacts, dental alloys, and brazing and solder alloys also contain silver.
💡 Additionally, silver is used as a water bacteriostat (preventing the growth of bacteria) in carbon-based filters.
Silver is not an essential mineral for humans and doesn’t have a purpose in the body.
|In Water As||AgO|
|Sources||Silver-laced activated carbon filter
Tailings and landfill sites
|Maximum Contaminant Levels (MCLs)||US EPA: 0.1 mg/L
WHO Guideline: 0.1 mg/L
|Potential Health Risks||Discoloration of the skin, eyes, nails, & internal organs
Seizures and organ damage
🩺 What are the Potential Health Effects of Silver?
The biggest risk of ingesting silver in water is that even low silver concentrations are known to build up in the body over time. While some ingested silver is removed by the body, most is absorbed and held indefinitely in the body’s tissues – particularly in the eyes, skin, and mucus membranes. This results in a condition called argyria, which is usually permanent.
According to Mayo Clinic, some of the long-term health effects of oral intake of silver are:
- Blue-gray discoloration of the skin, eyes, gums, nails, and internal organs
- Organ damage
Silver may also interact with certain prescription medications, including antibiotics and penicillamine.
The exact health effects of silver depend on how much silver is consumed and over what length of time.
🚰 How Does Silver Get Into Drinking Water?
Silver occurs naturally in the environment in various forms, including silver sulfide, silver oxide, silver nitrate, and silver salt. Water flowing through or over rocks and soils containing silver particles may pick up this metal and carry it to reservoirs, rivers, and aquifers that are used for public drinking water supplies.
The public water treatment process has used silver for disinfection purposes since the 1950s thanks to silver’s antibacterial properties.
Silver ions may also leach into water through the use of a silver-laced activated carbon filter. Some carbon-containing water filters contain silver to prevent the growth of bacteria on the filter media. The low levels of silver found in carbon filters shouldn’t pose a health risk in humans.
Finally, silver is released into the environment in industrial pollution, and almost three-quarters of all silver in the environment comes from tailings and landfill sites. Silver particles in the air are carried to surface water supplies in rain and snowfall.
📉 Do Water Treatment Facilities Monitor Levels of Silver in Drinking Water?
Yes, water treatment facilities monitor levels of silver in water, and prevent a toxic concentration of silver from contaminating water supplies.
There are a number of national guidelines and regulations that public water suppliers should use as guidance when treating water to reduce silver:
- Environmental Protection Agency (EPA) Secondary Maximum Contaminant Level: 0.1 mg/L
- World Health Organization (WHO) Guideline: 0.1 mg/L
Because silver is rarely found in dangerous concentrations in water, and because silver’s health effects are generally considered cosmetic (such as skin discoloration), the EPA doesn’t stringently monitor public water systems for silver removal.
There is no official primary MCL for silver in water, and while the EPA recommends that water facilities comply with the SMCL, facilities aren’t legally required to reduce their silver levels to below 0.1 mg/L. However, some states and local authorities may set their own legally enforceable standards.
According to the Environmental Working Group Tap Water Database, several facilities in Florida, California, and New Jersey are known to have the highest silver levels in their drinking water supplies.
🔎 How Can I Tell if Silver is in My Drinking Water?
You can’t tell by taste, sight, or smell whether or not your water contains silver. Silver is an invisible contaminant regardless of its concentration in water.
Testing a sample of your water is the only way to know for certain whether it contains silver. A laboratory test is the most thorough testing option for silver.
Laboratory tests provide a detailed report documenting exactly how much silver your water contains. You can choose to test for silver concentrations alone, or buy a test package that detects multiple contaminants – including silver – that commonly occur together.
Once you get your test results, you can determine a suitable silver removal solution for your water supply, if necessary.
👩🏽⚕️ How Can I Protect My Family from Silver in Drinking Water?
The best way to protect your family from silver in tap water is by installing a water filtration system or a water purifier.
Some of the best filters for silver removal are:
- Reverse osmosis – These filters remove almost 100% of total dissolved solids (for example, chemicals, lead and other heavy metals), as well as up to 90% of ionic silver. RO sends water through a sediment filter, a carbon filter, and a semi-permeable membrane, removing contaminants that affect the taste, odor, appearance, and quality of water. Most reverse osmosis systems are under-sink or countertop units.
- Distillation – This involves boiling water to form a vapor, which condenses in a separate container. The majority of impurities in water are unable to evaporate at the same temperature as water particles and are left behind in the boiling chamber. Distillation removes up to 98% of silver present in drinking water, but the process isn’t fast – it takes around five hours to distill just 1 gallon of water.
- Cation exchange – Strong acid cation exchange can also be used to remove silver from drinking water. Sodium is used in ion exchange systems to remove magnesium and calcium hardness minerals, as well as trace amounts of other contaminants, like silver. This method is typically used to remove silver from industrial wastewater.
If your water contains a lot of silver, it’s wise to avoid using carbon filters that are laced with silver, to prevent additional silver from contaminating your water.
⚠️ How Else Can I Be Exposed to Silver?
Aside from drinking silver ions in your water, you may also be exposed to silver from the following sources:
- Taking silver supplements. Some people take colloidal silver supplements due to silver’s supposed health benefits, including its immune-supportive properties. However, these supplements aren’t considered safe or effective, and silver has no known purpose in the body.
- Certain hobbies and occupations, such as jewelry-making, photography, and soldering, which involve the use of silver.
- Eating foods and drinking beverages that contain trace amounts of silver, such as mushrooms, whole grains, milk, and fish.
- Living in a region with heavy industrial activity, where silver is released into the atmosphere.
Silver isn’t thought to be absorbed by the skin, so touching silver or wearing silver jewelry isn’t considered dangerous. Ingestion of silver in food and water poses the biggest risk of toxicity.
📝 Where Can I Get More Information?
Follow the links below to learn more about silver in drinking water, including the potential health effects of drinking silver.
- WQA: Silver In Drinking Water
- World Health Organization: Silver In Drinking Water