The FDA is asking hand sanitizer manufacturers to submit research backing up claims of their products’ effectiveness. Are plain soap and water better?

Hand sanitizer, the gloppy alcoholic gel that’s nearly everywhere, and is supposed to keep germs from going anywhere, is getting a second look.

The U.S. Food and Drug Administration (FDA) wants manufacturers of hand sanitizers to submit research securing the efficacy and safety of their products.

Why? Just to be on the safe side.

Specifically, the FDA wants more data on the three active ingredients in 90 percent of all hand sanitizers: ethyl alcohol (also known as ethanol), isopropyl alcohol, and benzalkonium chloride.

The FDA isn’t saying it wants these products off the shelves, but the agency wants manufacturers to submit new research on the effectiveness and safety of hand sanitizers.

Overall, the agency wants evidence to support alcohol-based hand sanitizers are “generally recognized as safe,” (GRAS), which is the FDA’s system of classifying substances as safe to use for their intended purposes.

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One major concern is how ubiquitous hand sanitizers have become.

From the restroom to the airport to the grocery store, hand sanitizers have boomed since entering the market around 2009.

“Now, consumers are using these antiseptic rubs more often at home, work, and other places where risk of infection is low,” Dr. Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research, said in a press announcement.

“These products provide a convenient alternative when hand washing with plain soap and water is unavailable, but it’s our responsibility to determine whether these products are safe and effective so that consumers can be confident when using them on themselves and their families multiple times a day,” she said. “To do that, we must fill the gaps in scientific data on certain active ingredients.”

The active ingredient in these sanitizers is typically ethyl alcohol, the same found in distilled spirits. At 60 to 65 percent alcohol, these hand sanitizers are essentially 120-proof moonshine for your hands.

Since many people use hand sanitizers multiple times a day, the FDA wants data on long-term use, particularly in pregnant women and children.

The FDA says emerging science suggests that for some active ingredients, systemic exposure — what is detectible in blood or urine — is higher than previously thought.

All told, the FDA wants more information into how this regular and repeated exposure impacts human health.

Many of the hand sanitizers advertise they kill 99.99 percent of germs, another claim the FDA would like to see more evidence to support.

While killing germs can serve an important purpose, it’s the rise of the 0.01 percent of the leftover bacteria that have infectious disease experts looking for ways to approach the issue of antibiotic resistance.

Hand sanitizers aren’t expected to contribute to antibiotic resistance because they don’t contain antibiotics.

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The U.S. Centers for Disease Control and Prevention (CDC) recommends using regular plain soap and warm water.

Hand sanitizers, the agency says, should be used when these methods aren’t available.

While hand sanitizers and antibiotic soaps have their place, using them as frequently as we currently do may not be the best long-term solution for keeping people safe from disease causing germs.

The CDC is quick to point out all the times hand sanitizers shouldn’t be used. This includes when hands are especially dirty or greasy, as bacteria can cling in the nooks and crannies.

Hand sanitizers, the CDC says, don’t remove harmful chemicals, such as pesticides or heavy metals.

Other research, however, suggests that alcohol-based hand sanitizers are ineffective at protecting people’s hands from norovirus, the most common cause of the stomach flu.

There is evidence, however, that hand sanitizers can help prevent the spread of germs from the hands of people in the same household. Other studies show it can help prevent travelers’ diarrhea during international travel.

Overall, a large-scale review of all available evidence suggests hand washing with plain soap and water continues to be the best in preventing common illnesses spread by bacteria and viruses found on common surfaces.

Under its new request, the FDA recently issued a proposed rule for the data, which is open to public comment for six months.

After that, sanitizer manufacturers have a year to submit new data and information before the FDA makes its final ruling.

In 2013 and 2015, the FDA made rulings on the use of similar over-the-counter antiseptics, including consumer antiseptic washes and healthcare antiseptics.

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