Steer Clear Of Serving Acidic Drinks In Copper Cups For This Reason

Copper cups and shakers are eye-catching and attractive, but be careful what you use them for — you could inadvertently create a health hazard. The Food and Drug Administration warns that "High concentrations of copper are poisonous" and notes that "copper and copper alloys such as brass may not be used in contact with a food that has a pH below 6." Why? Copper can leach out — and into your stomach — when it comes into contact with acidic foods or drinks.

Copper is an essential nutrient, but too much can cause major problems. According to WebMD, copper poisoning can cause vomiting, diarrhea, fever, abdominal pain, and jaundice. In severe cases, it can even be fatal.

While most people default to glass over copper cups, copper is the go-to for serving one particular drink: the Moscow mule, a combination of vodka, ginger beer, and lime that was first invented to introduce Americans to vodka. Since copper is standard, you might assume that the drink is safe. But the pH of a standard Moscow mule is "well below 6.0," according to the Alcoholic Beverages Division of the State of Iowa. In 2017, the state issued an advisory against serving Moscow mules in copper containers thanks to the rising popularity of the drink.

Copper poisoning is rare, but better safe than sorry

Now, don't worry — there's probably no need to dump the drink if your host hands you a copper cup at a cocktail party. Professor Marc Solioz, a leading expert in copper toxicity, told Snopes that he "​​personally wouldn't be worried about" consuming up to five cocktails from a copper cup, even spread out over a few hours. However, Solioz stressed that the risk varies from person to person.

Consuming copper is especially risky for people with Wilson's Disease, a genetic illness that causes copper buildup in the body. According to the National Institutes of Health, Wilson's Disease can cause acute liver failure, which causes nausea and vomiting, poor appetite, fatigue, and discolored eyes. It can also cause depression, changes in mood, and psychosis, as well as issues related to the nervous system, like problems with physical coordination, stiff muscles, and tremors.

Nervous? Keep consumption to a minimum and don't nurse your drinks. According to a 2022 study published in the Journal of Environmental Health, the amount of copper in a Moscow mule exceeds the limits recommended by the U.S. Environmental Protection Agency after just 27 minutes. Even so, the EPA's recommendations are conservative — most people would need to down 30 mules in a day to reach dangerous levels. To stay on the safe side, opt for a glass. But if you really love the look of copper, you can find cups lined with nickel or stainless steel.