A new advisory says that the summertime favorite, the Moscow Mule could poison you. And it has to do with the Instagram-worthy copper mug.

The trendy, Instagram favorite drink, the Moscow Mule, has been growing in popularity over the years. The cocktail is simple: vodka, ginger beer, lime, ice and garnished with a lime and sometimes mint. But the most important part about the drink is the copper mug that the drink comes in. And that may be the thing that can make you sick.

new advisory bulletin was sent out by the Iowa Alcoholic Beverages Division to "advise licensees and permittees selling and serving alcoholic beverages in copper mugs of the applicable federal guidance and state regulations regarding the use of copper and copper alloys in contact with food and beverages."

According to the Food and Drug Administration guidelines, copper shouldn't come into contact with acidic foods with a pH below 6. This would include fruit juice, wine, vinegar and the Moscow Mule cocktail. The bulletin states that a Moscow Mule is "well below" a pH of 6.0.

When the copper comes into contact with acidic foods the copper can be leached into the food and cause copper poisoning. But don't throw out that copper mug just yet- check to see if the mug is lined with something other than copper. The interior of the copper mugs can be lined with other metals like nickel or stainless steel. The advisory says that these mugs can be used and are available on the market.

So next time you head to the bar and order yourself a tasty Moscow Mule, take a look at the inside of your to check if the mug is lined.