Of the two million-plus calls to U.S. poison control centers in 2015, almost half concerned kids aged six and under,  according to the latest data from the American Association of Poison Control Centers (AAPCC).   

That’s no surprise, says Carl Baum, Ph.D, professor of pediatrics and emergency medicine at Yale School of Medicine. Starting at age one, toddlers can get around on their own and develop enough finger dexterity to grasp all kinds of household items.

All of which increases the risk that they'll ingest potentially harmful things around the house. “The vast majority of exposures we see are kids picking up small objects and putting them in their mouth,” Baum says.

Here are the most dangerous household poisons for youngsters under age six, and what you should do to keep little ones safe. (Older kids are at somewhat lower risk, but parents should apply these tips to them as well.)

Alcohol-Based Products

Alcoholic drinks that are left out accidentally can tempt little ones. But household products that contain ethanol, including some hand sanitizers, mouthwash, and perfumes or colognes, are a more likely source of alcohol exposure for young children.

In fact, cosmetics and other personal care products were the most common exposures reported to poison control centers for children under six in 2015.

Some surprising products, such as vanilla extract, are also alcohol-based.

The amount that will make a child sick depends on the concentration of the alcohol and the size of the child, but just 2 ounces of wine can result in a dangerous level of alcohol in the blood of a 25-pound toddler. Alcohol can cause vomiting, drowsiness, confusion, and in severe cases, respiratory arrest and death. 

Protect and prevent: Keep alcoholic beverages and any other product that contains alcohol completely out of the reach of children; you might assume that a kitchen or bathroom counter is a safe spot, but it’s not. Even very young children can use a chair to climb up on counters.

Household Cleaning Products

Household cleaning products, such as bleach, drain declogger, and glass sprays, on the whole accounted for 11 percent of poison control center calls for children under six in 2015. While it depends on the particular substance, these often cause vomiting and abdominal pain if ingested.

Protect and prevent: Store them up high and out of reach of children. Always keep cleaning products in their original bottles; a different container may not have the same safety features, such as an on/off nozzle (which won’t stop older children, but may foil younger kids).

Also, consider opting for greener products, like those that carry the Environmental Protection Agency's Safer Choice logo. EPA scientists evaluate all such products for possible health and environmental hazards. For more on labels, go to GreenerChoices.org.

Opioids and Other Dangerous Drugs

The accidental ingestion of prescription medications, including sedatives, stimulations, and most commonly, opioids such as hydrocodone (Vicodin), oxycodone (Percocet), and buprenorphine (Suboxone), sends nearly 50,000 U.S. youngsters under age 5 to ERs each year. 

Over-the-counter medications and supplements can also be hazardous for young children. Adult-strength iron supplements can cause bloody diarrhea or vomiting in under an hour. Just one high dose of acetaminophen (the amount depends on your child's height, weight, and age) can cause liver damage.

Protect and prevent: Store medications where kids can’t reach them, preferably locked away. Make sure medicine containers, including those that are child-resistant, are always completely closed after use.

Keep medications in their original containers when you travel; daily pill organizers aren’t necessarily child-resistant. Ask visitors to secure medications they bring to your home.

Get rid of unused or expired sedatives, stimulants, and opioids properly by bringing them to a pharmacy or hospital, or by mixing them with coffee grounds or cat litter in a sealed plastic bag and throwing them away. Flush unused opioids down the toilet.

Button Batteries

The swallowing of foreign objects accounted for only 6 percent of all poison control calls concerning children under 6 in 2015. But in that group of objects, tiny button batteries, which are often used in hearing aids, watches, and even some toys, are especially worrisome. According to the nonprofit Safe Kids Worldwide, more than 2,800 kids a year in the U.S. are treated in emergency rooms after swallowing these nickel-sized batteries.

“Button batteries can be deadly to anybody that swallows them,” says Ruck. They can become lodged in children’s throats, posing a choking hazard. And if the chemicals inside the batteries leak out, they can damage the esophagus, causing bleeding and other tissue injury. 

Children who have a button battery stuck in their esophagus may lose their appetites, or have vomiting, nausea, coughing, wheezing, or fever. 

Protect and prevent: Make it your business to know which household products contain button batteries. Ensure that they can only be opened with a screwdriver or are similarly secure. (Duct tape can help, but may not completely deter a curious kid.)

Store any unused batteries where kids can't access them and dispose of used batteries right away. Don’t put new batteries into a product in front of children. If your child uses a hearing aid, purchase one that has a child-resistant battery compartment.

Laundry Detergent Pods

Young children may try to eat these small, brightly-colored pods, which are filled with highly concentrated laundry detergent. “To a toddler, they look like candy,” Baum says.

The soft plastic-coated pods can cause vomiting and breathing problems if swallowed, and chemical burns if toddlers get the fluid inside the pods in their eyes.

Calls to poison centers about these pods seem to be on the decline, since more rigorous safety standards went into effect at the end of 2015. (There were 12,594 reports of young children exposed to the pods in 2015, and 11,528 exposures in 2016.)

But they remain a significant problem, say experts. By the end of February of this year, U.S. poison centers had already received 1,558 calls about children exposed.

Protect and prevent: Consumer Reports recommends that families with children younger than six avoid laundry pods altogether, and we don't include them in our list of recommended detergents. If you do use them, keep pod containers closed, and store them up high and out of reach of kids.

Electronic Cigarettes

The liquid nicotine in electronic cigarettes can cause nausea and vomiting in children who swallow it, according to AAPCC.

And the numbers of young kids getting their hands on e-cigs appears to be on the rise. A 2016 study in Pediatrics found that back in January of 2012, only 14 children below the age of six had reported e-cigarette exposures. In April 2015, that number was 223.

The biggest threat, according to Bruce Ruck, Pharm.D., managing director of the New Jersey Poison Information and Education System, are the containers of liquid nicotine used to refill e-cigs.

Parents may accidentally leave used containers—which are often not child-resistant—out where kids can access them. But they may still contain residual nicotine fluid, and in flavors like bubble gum, that appeal to kids. 

Protect and prevent: Keep electronic cigarettes and liquid nicotine locked away and out of reach of kids. Never refill e-cigs in front of children. Dispose of empty nicotine containers in a receptacle children can't access.

If Your Child Ingests a Household Poison

What should you do if you know or suspect your child has ingested one of the substances or objects listed above? "Call for help as soon as the thought crosses your mind," advises Marvin M. Lipman, M.D., Consumer Reports' chief medical adviser. "Better a false alarm than an avoidable tragedy."

If you know or suspect that a child (or adult) has consumed a possible poison, call 911 immediately if he or she has collapsed, is unconscious, cannot be woken up, or is bleeding, says Ruck.

Do the same if you think opioids or other powerful prescription drugs or button batteries are involved, even if there are no visible symptoms. (In the case of medications, grab the drug container and any remaining pills if possible, to show first responders.)

If you're unsure what your child has gotten into, and see no symptoms, call your local poison control center, at (800) 222-1222, available 24 hours a day.

Staff there can help you figure out if your situation is an emergency, and guide your through treating your child. Or, try their new online tool

Don't attempt to induce vomiting or to neutralize a poison using vinegar or another substance unless a poison control staff member instructs you to do so.