The Dangerous Myth Of Mothballs

When you think of mothballs do you associate them with pesticides or more of a harmless home remedy that gets rid of just about any unwanted creature you could imagine? I’m thinking most of you feel this pearly white marble or flaked product must be as harmless as dishwashing soap because I see it used in some of the craziest ways. From whole boxes dumped into fireplaces to keep the chimney pest free, to hundreds of little white marbles encircling a house to stop unwanted snakes. What duct tape is to the husband who insists on fixing any household item on his own, mothballs are to that same DIY who has ANY kind of pest control issue.

Mothballs are a pesticide no ifs, ands or buts! Naphthalene is an active ingredient that is commonly used in mothballs and paradichlorobenzene is the other. Both are used in high concentrations in the making of mothball products. Let’s take a minute and see what these chemicals are;

Naphthalene was first registered as a pesticide in 1948. It is a solid that turns into a gas and it indeed kills insects and repels some animals. It is made from coal or crude oil but can also be produced when things burn. Cigarettes, exhaust from cars and forest fires all produce naphthalene. The main routes of exposure to naphthalene are inhalation and skin contact. Once inside your body this chemical breaks down and effects the liver, lungs and kidneys. Common symptoms of exposure are dizziness, headache and nausea. Children that may eat the mothball may have diarrhea, abdominal pain and painful and discolored urination. If someone breathes in enough of the vapor or eats a mothball containing naphthalene, they might develop hemolytic anemia. This is when red blood cells break apart, and no longer carry oxygen the way they should.

Paradichlorobenzene was first registered as a fumigant for moths in 1942. It too, goes from a solid to a vapor and poses many of the same risks as its cousin naphthalene. Irritation of the eyes and nose, nausea, dizziness and vomiting are signs of over exposure but paradichlorobenzene seems less likely to stay in the body as up to 50% can be excreted in one hours time with urination.

So Why Mothballs

Most mothball labels are pretty explicit about not breathing in vapors and avoiding skin contact. They also require that they be used in sealed containers where the gas cannot escape. I’ve not read any directions where it allows for using them in gardens, open areas or attics yet I see this way to often. Whenever you smell the strong odor of mothballs you are breathing in pesticides which in todays society I would think is strictly taboo. The little white marbles are pretty tempting to children as well- they pick them up out of curiosity and even eat them thinking they are some sort of candy.

Still the lure of a wonder product that has the reputation of chasing away pests and is not some sort of toxic spray must be comforting to some people. So many are absolutely convinced that mothballs are the answer to almost every pest control situation and are even less concerned about any hazards. I see it used for mice, squirrels, rats, snakes, roaches, unwanted dogs or cats, flies, fleas, ants and oh yes, even for moths. People with second homes such as snowbirds often sprinkle whole boxes around their home as they lock the door and head north for the summer. I have a few customers whose home wreaks so strongly of mothballs that we wear masks when we go in to perform service while they’re away. I’m guessing that most folks don’t even know that mothballs are pesticides and if they do, they are convinced they are fairly harmless. Besides, the ease of just throwing a 1/2 box out in the garage or up in the attic and letting the smell chase away their troubles is so much more simple than breaking out the spray.

Is there a myth associated with mothballs? Sure there is and I’ll bet you thought I was gonna shoot down everything that they are NOT good for- I might just do that but not today. The myth I’m exposing is one you’ve probably never thought of consciously or passed off with little concern. The myth that mothballs are safe little white marbles and Ok to walk over and around everyday-the myth that mothballs are not pesticides. That is the dangerous myth I want you to be aware of and the one I wish you’d avoid.

About The Bug Doctor

Jerry Schappert is a certified pest control operator and Associate Certified Entomologist with over two and a half decades of experience from birds to termites and everything in between. He started as a route technician and worked his way up to commercial/national accounts representative. Always learning in his craft he is familiar with rural pest services and big city control techniques. Jerry has owned and operated a successful pest control company since 1993 in Ocala,Florida. While his knowledge and practical application has benefitted his community Jerry wanted to impart his wisdom on a broader scale to help many more. was born from that idea in 2007 and has been well received. It is the goal of this site to inform you with his keen insights and safely guide you through your pest control treatment needs.
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  • jeffrey

    Is it OK to throw a bag of moth balls under a mobile home I have like 14 or more black widows at my place out after dark all the way around the trailer so I tossed one bag containing a lot of moth balls under the front only plus there is cats inside and one that goes in and out I barley done this I want to know if there there is any dangers having live pilot lights for furnace and water heater and plus the cats are starting to get sick throwing up is this not good I only want to rid the spiders

  • den

    My wife and I were storing a bunch of things for a few years. We put mothballs in any storage containers that had cloth – sheets, clothes, etc. Unfortunately some kitchen items were also mixed in some of the containers, and now all of them smell like mothballs pretty bad. We’re trying to clean all of it out – using vinegar and other methods – but I’m wondering if it’s even worth it. Will the kitchen items be toxic forever? How would I go about cleaning out an appliance – say, a coffee maker – that didn’t have actual mothballs in it but smells like it did?

  • tara

    Mu husband put about 10 or less moth balls in our crawlspace to try to help get rid of a skunk that is inhabiting it. Now I am concerned that he should remove them. How can he safely remove them & should we be concerned from breathing them for less than 24 hrs?

  • I don’t know the size of your crawl space but I don’t know if 10 is gonna be a big problem. – nor is 10 (or any amount) gonna dissuade a skunk from taking up residence. A trapper would be your best bet.

  • Not real sure to be honest. That smell permeates and is tough to get rid of. As far as the pesticide still being active– it may be but its a vapor that dissipates rapidly without the source.. The smell is what lingers–sometimes for a very long time as you no doubt have found out.

  • Klaudia

    Our apt. is attached to the garage. There is a door in between the garage and in our living place. I am 4 months pregnant and I always felt something but I was not sure what was it. I asked the owner to go to the garage and investigate the cause of the smell and he found a box of moth flakes. Now he throw it out, but the whole garage is smells from that stuff and the sad thing is the smell came into our apt. Now we sealed the door, but I am so scared I harmed my baby. I felt the smell the whole time. What should I do? I am so scared. Any suggestion, please? Thank you.

  • Kristi Stargazer-Lily De Seve

    i had something scratching at the wall in the bathroom behind the toilet and my brother said “put moth balls in the hole that is behind the toilet (pipes) and seal with steel wool.” normally, i google information when trying to “fix” a problem, but i didn’t come across anything that said “danger”, “toxic fumes” and “smells forever”. what have i done!!??? i dropped 3 napthalene balls in the wall (i heard them drop down deep, so i can’t get to them) and it STINKS! please tell me how long 3 balls will STINK(!!) and if that amount is anything other than a really unpleasant odor. p.s. why do the stores still sell this stuff???

  • Kristi Stargazer-Lily De Seve

    hi – just wanted to let you know we were able to vacuum the balls out of the wall using a piece of garden hose attached with duct tape to the vacuum hose, but the smell is still terrible and has changed overnight to a poop smell. i’ve ruined my vacuum cleaner, but those nasty things are gone and i didn’t have to cut a huge hole in the wall to get them out. hopefully, the smell will go away with the use of kitty litter and charcoal briquettes if needed. i’ve made sure that i can get these things out once i’ve put them inside!! 🙂

  • I’m glad you got them out… odor neutralizing sprays such as for pet odors may help for poo smell… available at your big box stores.

  • kathy

    hello i just read how dangerous moth balls were i got all but three balls from my trailer they fell down a hole where my pipes go down into the floor. will these three balls be harmful to my dogs, cats and even me and daughter

  • Can you seal up the hole at all? I doubt 3 will pose a problem but it couldn’t hurt

  • kathy

    could calk seal the hole?

  • If it’s not a big hole that would work well.

  • miky way kid

    I saw a mouse in my kitchen a few weeks ago. I went on line and read that mothballs are a good repellent for mice so I decided to purchase some mothballs. I have thrown about 10 all around the kitchen. I threw all but 2 behind the kitchen units. In other words, I can not remove these out of my kitchen because they are in hard to reach places. I have just been on line and came across an article on how mothballs are toxic and how they can cause serious health problems if inhaled .Anyhow, the smell of the mothballs is very strong around the kitchen. Its only been a few hours the mothballs were used. I now feel nauseous and sick. I have 2 children and a partner in the house. I am worried for my children, my partner and myself. I do not know what to do. Help

  • Sorry to hear…. It’s hard to say if your symptoms will persist or how long the smell and vapors will be unbearable. You just need to do what you can to remove them… Perhaps hire a handy man to help.. I don’t know of any ‘remedy’ to neutrilize the odor and depending on how many you placed, it may not be great to just let them ‘wear out.;

  • stinkyrugs

    My movers stored my rugs with mothballs rolled up inside them for 2 months. Now that the rugs are back and mothballs gone, the smell is lingering. Will it take a long while for the smell to go away or should I have my rugs cleaned? I am frustrated as I was never made aware that they would be storing my stuff with a pesticide!! Would the cleaning even help or will it just take time? My house smells terribly!! Thank you much!

  • Gotta try something– I would think cleaning and some odor absorbing product is worth a shot

  • Need to get them out— air the house out as much as you can as well

  • darkshakespear

    you know what mothballs are a pesticide. most who use them should know this. They do get rid of a ton of unwanted pests and work very well. its seems like a wonderful way of removing pests without having to spend 300 dollars for some idiot to come and spray more dangerous toxins around your home.

  • mfh

    What about putting one in each corner of your root cellar? Will the do anything to the food stored there?

  • One per corner doesn’t sound like much. But the directions say more of an enclosed place like a cabinet or closet. A better product might be the No Pest Strips – sold at Lowes ?? They are labeled (I believe) please check…. For food pantries etc. no smell- lasts 3 months and one should cover your entire area.

  • Lily

    We had a maintenance guy come for our mice problem and he put moth balls in the wall. Some were in my daughters room and I’m pregnant as well. It smells so strong. I was at work when this happened and fiancé didn’t tell me u till after it was done. Is it safe or does he need to take them out.


  • Barb

    I’m trying everything to keep the neighbor from walking his dog up to my shrubs & urinating on them. If I put moth balls down, will this stop the dog from doing his business there. Also, will it harm the squirrels or birds next to my feeders???

  • The Bug Doctor

    Moth balls are an “insecticide” not an animal repellant.

  • Moth balls were originally made for moths…. true they can and do kill/repel other insects because the are an INSECTicide…They won’t do a thing for detering dogs or other mammals.

  • islandives

    I want to know what happens when moth ball is dropped in still water? will it stop mosquitoes from laying eggs? thanks

  • Gee. Not sure– what can possibly go wrong with putting pesticides in water?? It’s not labeled for it.. It’s not safe… It’s not even in the spirit of what’s written here in my article which I’m pretty sure you didn’t take the time to read. Don’t do it!!

  • Betty

    Hi, we bought a house half a year ago and the upper level smells very bad like mothballs. It is worse when the temperature goes up. Now I found out that the previous owner threw mothballs between the roof and the insulation. We are not able to remove them, because we would have to remove the roof. How long are the mothballs dangerous? Shouldn’t they last only 3 months? I am very concerned about my child and us, because our bedrooms are all upstairs and we are inhaling that smell every day.

  • Heather Lawson

    We have an open barn loft in our backyard where we keep the hay for our 2 horses… By open I mean there is an open doorway and opposite of that is an open window. We get the driller bees and wasps really bad up there swarming around and I don’t want to spray when we have hay in there! I spray before we put the hay up there… And I do have the sticky tape bug catchers up there… That helps a little… Would like your thoughts on if you think it’s safe having a moth balls enclosed properly up there to deter the bugs… If you think it even would! Or is that a waste of time and do you have any other suggestions? I’m really just trying to keep them from wanting to hang out up there…as it makes it hard on us at times to want to get the hay!😁

  • Jiminy Kricketts

    hey, my main question would be this: are they effective at repelling insects of any and all kinds? my parents’ house wreaks. i was there last night. it scares me. but it’s a 35 minute drive from my house and the effects of my exhaust leak had probably started kicking in already, so any symptoms of moth ball poisoning probably were masked.

  • I’d get that leak fixed for sure.. As to your question–they are called “Moth” balls. There are instructions on the box but apparently not read very often

  • Being open like that lessens any type insecticidal vapors… too open and it just dissipates before doing what it’s suppose to. What type of wasps? Mud Daubers or the like should be of little concern– driller bees I take to mean carpenter bees? Also little concern as far as being attacked. You may want to call a pro in though if their really bad and there are nests of any kind.

  • The smell is still that bad? If you can smell it- it’s still time to take action. Not sure exactly how by what you described…I’d call out a pest company and look at remediation