Everything You Need to Know About Hand Sanitizers

The most common form of hand sanitizer, a gel-based formula, is thought to have been invented by a student nurse named Lupe Hernandez in Bakersfield, California, as an accessible alternative to washing. In 1988, a company called GOJO created Purell and perfected the formula that we typically use today.

The primary component of hand sanitizer is ethyl alcohol or isopropyl alcohol. Some sanitizers contain benzalkonium chloride. Other ingredients include antiseptics, sporicides that can kill bacteria spores on hands, and gelling agents that counteract the alcohol and keep your hands from drying out. Sometimes fragrances or colorants are added as well.

Alcohol is bactericidal, not bacteriostatic, meaning it kills bacteria. It does this by altering proteins vital to the cell's survival, rendering it incapacitated and killing it in seconds. A bactericidal agent prevents the growth of further bacteria. Both ethyl alcohol and ispropyl alcohol can take out viruses such as the hepatitis B, influenza, and herpes. Ethyl alcohol can inactivate HIV and the rotavirus, among others. Among the bacteria alcohol can kill are staph aureus, E. coli, and salmonella typhosa as well as funguses and the bacteria that cause tuberculosis.

The concentration of alcohol in hand sanitizer is a vital component in its effectiveness. A range of 60% to 90% ethyl alcohol concentration is most effective, with most solutions falling between 60% and 80%. Lower concentrations, such as sanitizers with a 40% alcohol base, take longer to eliminate microorganisms and are too weak to truly be useful.

Hand sanitizer is widely considered a less effective alternative to washing your hands with warm, soapy water. Soap and water reduce the number of all germs, kill numerous harmful organisms, and also remove dirt and other debris. However, when hand washing is not available, or in countries lacking adequate water supplies, hand sanitizers may prove to be a viable personal hygiene option.

Hypothetically, hand sanitizer could disinfect surfaces, but its components and consistency make it more suitable for skin. On hard surfaces, it may leave a slightly sticky residue. Other alcohol-based cleaners, like disinfectant wipes and sprays, are better for cleaning surfaces like door handles and countertops. Rubbing alcohol can also be used to clean small items and spaces, like phone cases.

Do-it-yourself hand sanitizers may or may not be effective against bacteria, mainly because the percentage of alcohol is difficult to get right. Remember, the largest component needs to be alcohol and it has to be of a certain concentration to be effective. Factories follow a specific formula, and you may not have the right one at home. Hand washing remains a better option than DIY hand sanitizers, and if you need a bottled option, it's best to opt for store-bought.

Hand sanitizers can help prevent infectious diseases, and some research suggests they can prevent the spread of infection when used correctly. A trial conducted at an acute care facility found a significant decrease in infection rates when patients and caregivers increased the amount of hand sanitizer they used over 10 months.

If your hands are visibly dirty, you have just used the bathroom, or you have come in contact with a sick person, hand sanitizers are not the most effective way to remove all bacteria and other germs and debris. If you're coming into contact with an immunocompromised person, washing your hands will reduce the transmission of any harmful organisms you might be harboring.

The alcohol in alcoholic beverages is usually the same as the type in hand sanitizer: ethyl alcohol or ethanol. Some hand sanitizers are made from isopropyl alcohol, but this less common. Other harmful ingredients in hand sanitizer, of course, make it unsafe for human consumption. Some people make their own hand sanitizer with vodka, but most vodkas do not have a high enough alcohol percentage to serve as a sufficient disinfectant.