A federal agency has given its approval for a powdered form of alcohol meant to be mixed with water to create an alcoholic drink.

The controversial product known as Palcohol, which comes in plain and flavored varieties, briefly received the approval of the Alcohol and Tobacco Tax and Trade Bureau last spring before it reversed itself, saying the label approvals had been granted in error.

Now those issues have been resolved and approval has been given for four varieties of Palcohol, bureau spokesman Tom Hogue said.

Despite the federal approval, states still have the right to regulate sales of any form of alcohol within their borders, he notes; the bureau's concern is whether the product accurately matches the label description of the contents.

"Potential for abuse isn't grounds for us to deny a label," Hogue said.

Palcohol would be sold in a small packet, and the freeze-dried alcohol is intended to be mixed into water to create an alcoholic cocktail. A statement on the company's website said the product could be for sale this summer.

Company founder Mark Phillips said he thought up the idea for the powdered alcohol as a way to enjoy an alcoholic drink after hiking or other outdoor activities without having to carry heavy beverage bottles.

Several U.S. states have initiated efforts to ban powdered alcohol. Colorado lawmakers are considering legislation to stop its sale out of concern that minors could abuse it or that the small packets could be easily sneaked into public events.

University of Colorado medical toxicologist Dr. Kennon Heard, who is also an ER physician, has expressed concerns over the product.

"Given the flavors it comes in, there's the potential for it to be very appealing to small children," he said in an interview last year.

In addition, because it is alcohol in an entirely novel form, people unfamiliar with its potency could inadvertently misuse it, he said.

Attorney Robert Lerhman expressed similar concerns last year when Palcohol first won the later-retracted approval.

"Nothing even close to this has been on the market in the recent past in the U.S., or ever," he said at the time.

"Underage drinking is a big concern when it comes to powderized alcohol," he said. "I do think parents and teachers -- this probably will get their attention in a big way."