Copper mugs have become increasingly popular for serving cocktails like the Moscow Mule, but concerns about the safety of drinking from copper vessels have also surfaced. This is because putting an acidic drink in a copper cup can cause a reaction that could erode its lining, raising the copper level and eventually poisoning the drink.
However, copper mugs are safe for food and beverages if lined with a non-reactive metal such as nickel or stainless steel. Just keep your drink from sitting for too long, no more than 2 hours maximum, or you run the risk of copper poisoning.
To end the controversy about whether copper mugs are safe, we have compiled all the relevant information in this article.
What’s with Moscow Mule Copper Mugs?
The famous Moscow Mule is traditionally served in a copper mug, which has become as iconic with the cocktail as a stemmed glass with a martini or a thin flute with champagne. Simply put, a Moscow Mule is not a Moscow Mule if it is not in a metal cup. This detail makes this drink unique and has helped make it famous.
But the drinkware’s main purpose is not its looks. Copper maintains the drink’s cold and war temperatures longer than regular glasses. Some people say copper also gives the drink a unique metallic flavor, but this is just their opinion.
History of Copper in Health Care
Image by COPPER H20
Since ancient times, copper has been valued for its antibacterial properties. The ancient Egyptians associated the metal with eternal life. They also used copper extensively to make pots, mirrors, jewelry, and weapons. While copper has many uses, one of the most important is to make safe water storage vessels.
As a result of this discovery, some cultures, such as the Hindus, used copper in their medicine. Ayurvedic medicine took it one step further and recognized that copper was an important metal for the health of the human body.
FDA Warning Against the Use of Copper Mugs
The growing popularity of Moscow Mules has raised concerns about the safety of copper mugs with this beverage.
Many states, including Iowa, have adopted the federal Food and Drug Administration’s Model Food Code, which forbids copper from coming into direct contact with foods with pH levels lower than 6.0. Vinegar, apple juice, and wine have pH levels lower than 6.0.
A classic Moscow Mule has a pH of less than 6.0. This means that copper mugs with a copper interior are not permitted to be used with this beverage. Copper mugs coated on the inside with another metal, such as nickel or stainless steel, are allowed and frequently available.
The statement says that high levels of copper are poisonous and have caused illnesses that spread through food. Copper can get into acidic foods when copper and copper alloys come in contact with them.
When water and carbon dioxide are mixed, they make an acid. This acid leaches copper from the plumbing parts, and the leachate then gets into drinks and causes copper poisoning.
What’s the Truth About Copper Mug Poisoning?
Copper mugs can be safely used to serve Moscow mules. Most mugs used for this purpose are made of a different material that eliminates any risk of copper exposure or toxicity.
Copper mug poisoning is only possible with unlined copper mugs if the body is exposed to a large amount of copper.
The US National Research Council (US) Committee conducted a study in which they found that symptoms of copper toxicity appeared after consuming 30 milligrams of copper per liter and sitting in an unlined pure copper mug for hours.
To get copper poisoning from a Moscow mule, a guest would have to drink a liter of the cocktail from an unlined copper mug sitting in the freezer for several hours. This is unlikely to happen, but it cannot be ruled out.
As a result, some bar owners may choose to stock up on lined copper mugs for ease of maintenance and fewer health issues. Many Moscow Mule mugs sold today are lined or copper-plated on stainless steel, nickel, or tin.
Symptoms of Copper Mug Poisoning
Copper is naturally found in many plant and animal foods. Still, the human body only stores about 50–120 milligrams (mg) of it. A doctor can determine how much copper is in a person’s body through blood tests.
The National Institutes of Health (NIH) recommends that adults not consume more than 10 milligrams of copper daily. Copper poisoning can cause many different symptoms, including:
- Stomach pain
- Nausea and vomiting
- Blue, green, or dark stool with blood
- Extreme thirst
- Tachycardia or abnormally fast heart rate
- Fever or chills
- Sore muscles
- Changes in taste, loss of appetite, or anorexia
Copper poisoning can also cause the following neurological and mental symptoms, as well as other serious health problems:
- Changes in mood
- Symptoms of depression or anxiety
- Difficulty focusing
- Kidney and heart failure
- Loss of red blood cells
- Liver disease
- Brain damage
When is It Risky to Drink from Copper Vessels
Like with everything else, there are some risks associated with copper mugs. It all depends on how you use them and what you store in them. Here are some things to watch out for when using a copper vessel or mugs:
Storing Acidic Liquids or Foods
If the copper vessel is not lined, the copper that touches the acidic substance may react and release a lot of copper salts, such as blue vitriol (bluestone), copper sulfate, and verdigris. This can be dangerous because it can cause copper toxicity and other health problems, some of which can be fatal.
Some of these are pickled foods, honey, milk, other dairy products, and anything citrusy, like lemon, lime, or orange juice.
Exposure to Heat
When copper is heated, it becomes more reactive and is more likely to give off more copper ions when it comes in contact with another substance. This is also why it rusts more quickly, so you should not put copper dishes in the dishwasher.
Remember not to put hot liquid into it when storing liquids in copper vessels or mugs. This is why Copper pots and pans are lined with copper because it helps heat spread out more evenly–but if the lining is damaged, you should never use the pot or pan again.
Improper or Irregular Cleaning
Copper tarnishes over time. Tarnish is not dangerous by itself and can make copper less reactive when coming in contact with water. However, it can pose a threat when the copper surface has started to rust and form a green patina (the result of corrosion). Regular cleaning is important to get the most out of storing water in copper and as a safety measure.
When cleaning your copper items, you should avoid using harsh chemicals. Copper does not react well with harsh chemicals or the dishwasher. Check out this guide to learn more about how to clean copper mugs.
What Not to Drink in Copper Mugs?
Copper cups are not FDA-approved for citrus and acidic drinks. Avoid drinking the following in copper mugs:
- Beer (excluding ginger beer)
- Lime juice
- Lemon juice
- Tomato juice
- Gatorade and Powerade or other sports drinks
- Unmixed hard liquor like Gin, whiskey, vodka, and brandy
If you want to serve any of these beverages at your bar, restaurant, wedding, or birthday celebration, use glass cups.
Safety Tips When Using Copper Mugs
It is difficult to determine whether a drink is healthy and safe to ingest after being stored in a copper vessel for extended periods. Here are some tips to help you serve cocktails in copper mugs safely:
- Serve highly acidic drinks, like vodka, in a copper vessel with a food-grade inner coating, as all Advanced Mixology copper mugs have.
- When serving a cocktail in a copper mug, the inner part should be nickel or stainless steel. The inside silver lining may appear cheap, yet it protects the contents from contamination.
- Make certain that the Moscow mule copper mug’s interior is not made of pure copper.
- Leave your drink in a copper mug for a short time, at most 2 hours.
- Drink your alcoholic beverages in a glass container if possible.
Are Copper Mugs Safe FAQ
Is drinking from a copper cup healthy?
UPMC experts say drinking from a copper cup provides no meaningful health benefits, yet using these cups is not inherently bad. “Drinking from a copper cup probably has no meaningful health benefit or risk,” stated Michael Lynch, MD, medical director of the Pittsburgh Poison Center.
Is it safe to drink hot coffee in a copper mug?
A copper mug for your morning brew is acceptable, but only if you use it with iced coffee. Also note that the mug’s interior must be plated with a safe metal for consumption–such as stainless steel, tin, or nickel.
Can you put Coke in a copper mug?
No. The Model Food Code of the Food and Drug Administration “prohibits copper from coming into direct contact with foods that have a pH below 6.0.” Juices, alcohol, soda, coffee, and tea are a few examples.
Does milk react with copper?
It is dangerous to store curd or milk product other than water in a copper vessel or mugs. Copper is likely to react with the minerals and vitamins in milk, which can cause food poisoning. Not only that, but the reaction might also cause nausea and anxiousness.
What are the side effects of drinking from the copper vessel?
Suppose you have been drinking water held in a copper bottle or vessel for a long period. In that case, you are in danger of copper toxicity. It has the possibility of causing severe nausea, dizziness, and abdominal discomfort, as well as liver and kidney failure.
In short, it’s unlikely that you’ll get sick from using a copper mug. The only danger is that your drink will become contaminated if you let it sit for too long. Fortunately, most copper mugs today come with tin or stainless steel lining when purchased as a set to eliminate that concern.