Q. We have an older friend who has a thing about mothballs. She uses them extensively throughout her house in every closet and around all the baseboards. When you walk in the door the smell is very strong.
Can excessive mothball exposure be toxic? She is losing weight inexplicably and we are worried.
A. Mothballs used to contain naphthalene. Because this chemical was flammable, it has been phased out in favor of 1,4-Dichlorobenzene (para-Dichlorobenzene). A mothball is a compressed ball of chemical pesticide. As it volatilizes (turns into a gas) it liberates a chemical that is highly toxic to moths.
Mothballs can be toxic in excess. If children or pets swallow mothballs, poisoning may result in serious consequences including jaundice, anemia and kidney damage due to destruction of red blood cells. Parents must keep mothballs out of reach.
Long-term exposure to fumes is harder to assess. At high concentrations, symptoms such as eye irritation, weakness, dizziness, weight loss and liver problems have been reported.
What is less clear is lower-dose, chronic exposure. The Environmental Protection Agency states that:
“The primary exposure to 1,4-dichlorobenzene is from breathing contaminated indoor air. Acute (short-term) exposure to 1,4-dichlorobenzene, via inhalation in humans, results in irritation of the skin, throat, and eyes. Chronic (long-term) 1,4-dichlorobenzene inhalation exposure in humans results in effects on the liver, skin, and central nervous system (CNS). No information is available on the reproductive, developmental, or carcinogenic effects of 1,4-dichlorobenzene in humans. A National Toxicology Program (NTP) study reported that 1,4-dichlorobenzene caused kidney tumors in male rats and liver tumors in both sexes of mice by gavage (experimentally placing the chemical in their stomachs). EPA has classified 1,4-dichlorobenzene as a Group C, possible human carcinogen.”
We suspect that if you can smell the distinctive aroma of mothballs when you enter your friend’s house, she is exposing herself to too much pesticide.

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  1. G

    I did not know that moth balls are dangerous to ones health. Yes, I used some a few days ago. I noticed that my eyes, throat, was bothering me. I checked on the web on the effects on moth balls. I quickly removed the moth balls and my breathing got better. However, my throat still feels funny. So, out to the Doctor’s office tomorrow.
    Be careful of the use of moth balls.

  2. MaK

    HaHa I didn’t know about moth balls if it is danger, then why our government can allow to use mothballs?

  3. Michelle
    United States

    I have the worst of it all. I am staying with a family friend for the next few months. I found out she keeps mothballs all over the house, including the fridge! I didn’t notice the effect it has on the food, but the first day I took my lunch to school I noticed that my food basically tasted like mothballs and definitely had the smell. Now I am worried that I am being poisoned anytime I eat. But, I don’t have another choice.

  4. Bessie S.

    My mother in law put mothballs all over the garage, most of the time the garage is closed. Since the day my husband used it, I inhale it accidentally after 2 days I got headache, I feel nauseated and my eyes got irritated, I tried to tell them that its dangerous to the health but they are not listening to me.
    My husband and mother in law are both love the smell. Recently they both having nausea and headache too, but myself is the worst, I can’t stop coughing when my throat starting to itch. do I got the poison in my system? I’m getting worried

  5. Sandra Walker

    I just put moth balls in my attic to run off squirrels. The smell is all through the house, but the squirrels are gone. My eyes are very irritated. Feel like sand in them, but that’s my only problem. Will the smell eventually go away? It’s like choosing the lesser of two evils. Lord help.

  6. lester

    I got a couch from my uncle. It was my grandma’s I picked it up. He had it in his garage. He had moth balls in his garage the odor was very strong. Since then I was the only one that ever sat in it. But I notice I’ve been feeling weird lately. My eyes are bothering me a great deal. Really bad headache, nauseous dizzy, extremely light headed. wtf. Why did he keep this in the garage of mothballs. My wife is sick now I am sick been sick since the couch came in the house. I just washed it, but right now I want it out of my house. Can’t risk my family being sick.. I can’t breathe. We all are sick.

  7. GA

    Is there a safe product that, unlike cedar, does not have an odor that permeates clothing but prevents moth destruction?

  8. jml

    Leslie, I have a 70+ lady friend and every time I have slept over at her house I have a headache, and can smell mothballs as I enter the house. This time another lady and I were both aware of the smell and had headache next day. In all my research on line since home, your note was the clearest and helped me realize that she has lost weight has major health issues and will not listen to me. So I will copy off your note… were you ever able to help your friend realize the problem?

  9. Cindy B.

    Geez – my mother did that too. Mothballs everywhere (yuck!) And my mother, though charming, was definitely mentally ill, a manic depressive stuck most of the time on the manic side. Who in their right mind would want to inhale a snootful of bug poison with every breath…

  10. CNW

    Sad, but true. My mother used mothballs with increasing vigor as her dementia progressed. The sense of smell diminishes in some cases of dementia. She had no idea that her house smelled like a chemical plant.

  11. Leslie N.

    It’s quite possible that both the mothball obsession and the weight loss are warning signs of dementia.
    The weight loss – because the awareness that it’s time to eat and the ability to choose and prepare food are often compromised early in the disease
    The mothballs – because wildly extreme concern about a minor issue – mothballs everywhere – is often a sign that judgement and cognition aren’t what they used to be.

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