Is bug repellent bad for you?

Dealing with pesky insects is a fact of life when you spend time outside in warmer weather. But keeping ticks and mosquitos at bay is about more than avoiding itchy bites. Both ticks(Link is external) (Link opens in new window) and mosquitos(Link is external) (Link opens in new window) can transmit multiple diseases and potentially cause serious health issues.

But before you go dousing yourself and your children in bug spray, you may want to investigate what you’re using and how you’re using it. Skin-applied tick and insect repellents are pesticides — substances meant to prevent, destroy or repel pests. While many are effective and safe to use in certain doses, it’s important to know what you’re putting on your body and make sure you’re using it safely.

Here’s what you need to know:

How do insect repellents work?

Insect repellents deter mosquitos, ticks, biting flies and other insects by interfering with their ability to find a host. Mosquitos and ticks use heat, movement and visual cues to zero in on a possible host. But ultimately, they are attracted by skin odors and the carbon dioxide we exhale.

When you apply repellent, the active ingredients affect a tick or mosquito’s senses, such as smell and taste. Repellent can make it hard for them to find you, identify you as a host or even land on you.

What’s in bug spray?

How long and how well a bug repellent offers protection varies based on its active ingredients, which may be chemical or natural (plant-based). To guide consumers, the Environmental Protection Agency (EPA) evaluates the active ingredients used to repel insects to see how safe they are and how well they work.

The EPA provides a registry of approved skin-applied repellents that are both safe and effective when used as directed. The most common active ingredients in EPA-registered insect repellents include:

• DEET: More than 500 EPA-registered products contain DEET and include lotions, sprays, liquids and wrist bands. While the concentration of DEET in a product can range from 4% to 100%, the Centers for Disease Control and Prevention (CDC) reports that concentrations greater than 50% provide no added protection.
• Picaridin: Also known as KBR 3023, picaridin is a synthetic version of an ingredient found in pepper plants and the active ingredient in more than 40 EPA-registered products. It’s non-toxic but may cause eye irritation and hasn’t been studied as well as DEET.
• Oil of lemon eucalyptus (EOC): Different from lemon eucalyptus essential oil (which is not an EPA-approved repellent), EOC comes from the leaf extract of lemon eucalyptus trees. It’s then processed to increase its ability to repel bugs.
• IR3535: More than 40 products on the EPA’s list of registered repellents contain IR3535. This synthetic amino acid is odorless and is effective against disease-carrying mosquitos and ticks.

The EPA has evaluated some natural bug repellents including citronella, geranium and peppermint and found them to be safe. But they have not been approved for effectiveness.

How much bug repellent is safe?

The concentration of active ingredients in insect repellents can vary, so understanding the safe range to use is important. While a higher concentration may provide longer protection, it can also potentially increase the risk of side effects.

Safe and effective concentrations of common repellents are:

• DEET: 20% to 50%
• Picaridin: 5% to 20%
• Oil of lemon eucalyptus: 10% to 30%
• IR3535: 10% to 30%

While there’s no recommended amount of bug spray to use, experts recommend using enough to create a thin layer of protection on your clothes and exposed skin. But do not use any more than necessary.

Using bug spray for babies and kids

There are different guidelines for using insect repellent on infants(Link is external) (Link opens in new window) and children. According to the American Academy of Pediatrics, no insect repellents should be used on children younger than 2 months. The CDC also recommends avoiding products containing oil of lemon eucalyptus with children under age 3.

Children under the age of 10 should not handle insect repellent — it’s likely to end up in their nose, mouth and eyes. Instead, put the repellent on your hands and rub it onto your child.

Take these steps if you suspect your child is having an adverse reaction to repellent:

• For localized reactions, such as redness, burning or rash, wash the treated skin, remove treated clothing and call your primary care physician or your local poison control center.
• Mild stomach irritation, nausea or vomiting is often associated with swallowing small amounts of repellent. Call your local poison control center or primary care physician.
• Symptoms related to the nervous system such as disorientation, seizure, low blood pressure or very slow heartbeat can happen if large amounts of repellent are ingested. Call 9-1-1 or bring your child to the emergency department.

How to find the right bug repellent (and apply it correctly)

To register with the EPA, skin-applied bug repellent is evaluated and approved for human safety and effectiveness. The EPA’s insect repellent search tool allows you to search its list of registered repellents by protection time, active ingredient and other product-specific information.

When applying any bug repellent, follow these guidelines to stay protected and safe:

• Apply bug repellent after sunscreen and avoid combination products, which may overexpose you to repellent chemicals during sunscreen reapplication.
• Follow the product label, applying repellent to exposed skin or clothing but not beneath clothing.
• Use just enough to cover — more is not better and can increase risks.
• Avoid applying to cuts and irritated skin.
• Don’t apply it directly to your face, but instead spray it on your hands and rub it onto your face without going near your eyes, nose, mouth or ears.
• Wash your hands after application and before eating and drinking.
• Wash the repellant off your skin and wash treated clothing separately if you won’t be exposed to insects anymore that day.

Bug spray alternatives

Insect repellent isn’t the only way to protect yourself and your family from mosquitos and ticks. Instead, you may want to consider:

• Clip-on products that disperse repellent near your body
• Clothing that covers your arms and legs
• Clothing treated with permethrin, an insecticide sold specifically to treat clothing
• Mosquito netting for baby strollers and carriers
• Spatial repellents that disperse repellent in an outdoor area (lantern, torches, candles)

To learn more about protecting yourself and your family from ticks and mosquitos, reach out to your primary care physician.