11 Things You Should Never, Ever Flush Down the Toilet

Some things you should never flush down the toilet may surprise you.

Thinking about flushing that tampon down the toilet? You may want to think twice about that one. “People flushing things that should not be flushed is a problem all over the country,” says Cynthia Finley, PhD, director of regulatory affairs for the National Association of Clean Water Agencies (NACWA).

Those rogue items can cause direct problems for you when they get lodged in the pipes leading from your home to the sewer, but they can also create larger systemic problems when they build up in the sewer system on the way to the wastewater treatment plant.

Unless it’s one of three specific items, put it in the garbage can instead.

“It’s the three Ps: toilet paper, pee, and poop, essentially,” says Cory Schultz, an environmental specialist with the Minnesota Pollution Control Agency. “Those are the things that toilets were designed to handle.”

Toilet paper is designed to break down very quickly once it’s flushed, so it doesn’t clog your pipes or build up in various places along the way to the wastewater treatment plant, like other items can (and do).

But just in case you were wondering, here are some commonly flushed items that you should definitely not flush:

What Not To Flush Down the Toilet

Tissues

If you’ve always assumed that tissue was pretty much interchangeable with toilet paper, this one might surprise you. “They are treated so they don’t fall apart when you hold them in your hand to blow your nose,” says Finley. “That means they also don’t break apart very quickly in water, once they’re flushed.”

Wipes

Baby wipes, hand wipes, cleaning wipes—whatever kind of wipes you have—it’s better to throw them away in the trash can. According to Finley, most wipes are not designed to be flushed. Why? “When you use them, you don’t want those wipes to break, so they are made to be strong, which is good for their purpose,” she explains. “But if they’re flushed, they just don’t break apart.”

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Menstrual supplies

Pads and tampons don’t break down when flushed. So you should wrap them in toilet paper and dispose of them via the trash can, instead of flushing them down the toilet. If you flush them, they can lead to clogged pipes that would have to be cleaned out, either in your home or further down the system.

Related: From Period Underwear to Menstrual Cups, Here Are 11 Great Tampon Alternatives

Paper towels

Paper towel commercials always hype the strength of their product. But if that paper towel is strong enough to tackle big messes, that also means it’s not going to break down when flushed, says Schultz.

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Cooking oil or grease

Think about what happens to that hot cooking oil or grease when it cools down. It congeals. Now, imagine what could happen if you—and lots of other cooks—flush it down your toilet.

“I’ve seen what they call fatbergs, these big grease balls in collection systems,” says Schultz. “If they’re not able to be mechanically moved, someone has to get in there and remove them with whatever tools they have.”

Hair

If you clean out your hairbrush or your shower drain, you should dispose of the hair in, you guessed it, the trash can, not down the toilet.

Related: From Period Underwear to Menstrual Cups, Here Are 11 Great Tampon Alternatives

Dental floss

Another nope here. “It’s so strong,” says Finley. “The floss itself, the kind you wrap around your fingers, will wrap itself around treatment equipment and it has to be cut off with a razor blade, and we don’t want our sewer workers to have to do that.” Don’t flush those little plastic flossers, either, since they won’t break down and would have to be physically removed and taken to a landfill.

Diapers

You probably (or hopefully) won’t get a diaper to successfully go down the toilet, but that doesn’t mean that some people haven’t tried. And some have even succeeded, but this is a definite no-no. Flushed diapers can create big clogs.

Pills and medications

According to the Minnesota Pollution Control Agency, pharmaceuticals that get flushed can pollute the water supply and unintentionally expose people (and animals) to the chemicals in those drugs. But don’t just toss those unwanted medications in your trash can, either. Check with your local pharmacy, police department or hospital to learn about drug take-back programs in your community.

Kitty litter

“Do not flush cat litter,” says Finley. “It will clog up the pipes. It can also contain parasites that are not healthy to be putting into the wastewater treatment system.” So don’t scoop and flush, either, she adds.

Other assorted detritus

People try to flush all sorts of other items that have no business going down the pipes, including:

• Condoms

• Cotton pads

• Cotton swabs

• Cigarette butts

• Chewing gum

• Contact lenses

All of that stuff can wind up building up or getting tangled up in the wastewater treatment equipment, causing major headaches and necessitating removal, which requires time and money. “I’ve seen everything from money, glasses, toys, towels, even golf balls,” says Schultz. Just find another way to dispose of those items without resorting to flushing.

Next Up: Experts Reveal the Best Way to Dispose of Tampons

Sources:

• Cynthia Finley, PhD, director of regulatory affairs for the National Association of Clean Water Agencies (NACWA)

• Minnesota Pollution Control Agency. Don’t flush medicines down the drain.

• Cory Schultz, an environmental specialist with the Minnesota Pollution Control Agency

• Take Back Your Meds. Medicine Disposal Myths and Facts.