Mothball Madness: The Hidden Dangers of Traditional Chemical Mothballs

This in-depth article reveals the extensive health dangers, environmental impacts, contamination risks, and safer non-toxic alternatives.

February 8, 2024
min read
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For over a century, traditional mothballs infused with nasty chemicals have been the go-to solution for keeping moths and other fabric pests out of clothing, textiles, and valuables. The strong fumes emitted by these pesticide-laden products do effectively deter moths and larvae initially. However, the toxins in traditional mothballs also put your health, home, and environment at serious risk.

In this in-depth exposé, we will uncover the extensive dangers posed by old school chemical mothballs. We’ll examine the hazardous active ingredients found in traditional mothballs, the toxicity and environmental impact, and safer natural alternatives you can turn to instead. Let’s dig into the mothball madness and learn why it’s time to ditch these risky relics once and for all!

A Brief History of Toxic Mothballs

Before examining the dangers, let’s first take a quick look at the origins of chemical mothballs:

1800s - The mothball concept originated in the late 1800s as people sought ways to protect clothing from insect damage. Early moth preventatives included herbs like mint leaves or sachets of strong spices.

1867 - The first processed mothball products emerged, often a mix of herbs and chemicals like creosote or naphthalene. They had limited effectiveness but introduced the distinctive mothball scent.

1900s - Manufacturing advanced, allowing mothballs to be mass produced using more potent synthesized chemicals. This increased effectiveness but also toxicity.

1930s - Paradichlorobenzene (PDB) became a popular chemical additive to mothballs due to its strong vapours. Naphthalene mothballs also proliferated.

1940-50s - Chemical mothballs soared in popularity for domestic and military uses. Aggressive marketing hyped their effectiveness while downplaying risks.

1970s - Growing awareness of environmental and health concerns caused some regions to restrict certain chemicals in mothballs like PDB.

Present - Many households still perceive chemical mothballs as a necessary evil against fabric pests. But safer alternatives are now widely available.

Now that we’ve seen a quick history of how toxic mothballs came to be commonplace, let’s examine exactly what worrisome substances traditional mothballs contain.

The Nasty Chemicals in Traditional Mothballs

There are two primary chemicals used in the majority of traditional mothballs sold today:

Paradichlorobenzene (PDB)

Paradichlorobenzene, also known as PDCB, is a chlorinated aromatic hydrocarbon commonly used in mothballs. It is a white crystalline solid that emits a strong, pungent odour as it sublimates from solid to gas.

PDB mothballs are now banned in several countries and U.S. states due to toxicity concerns, but still widely available elsewhere. Ironically, the same fumes that repel moths also endanger human health.


Naphthalene is another crystalline solid used as an active ingredient in mothballs and other fumigants. It is derived from coal tar or crude oil refining. Raw naphthalene has a strong, unpleasant smell that mothballs release as the chemical volatilizes.

While naphthalene and PDB work well to repel moths, both chemicals are also categorized as suspected carcinogens and broad-spectrum pesticides. Let’s look closely at why these substances are so problematic for your home and health.

Toxic Effects of PDB Exposure

First, paradichlorobenzene, the chronic chemical fumes emitted by PDB mothballs present a wide range of risks:

Headaches & Lightheadedness

Headaches are commonly reported after inhaling PDB vapours, even at low concentrations. The chemical causes changes in blood pressure and reduces oxygen to the brain. Dizziness, fatigue, and overall discomfort result.

Nausea & Vomiting

Stomach issues like nausea and vomiting are also frequent complaints after mothball exposure. Inhalation can cause gastrointestinal irritation, inflammation, and sensitivity reactions.

Liver & Kidney Damage

Long-term exposure is linked to impaired liver function and reduced kidney perfusion in research studies. The kidneys work overtime to filter out mothball chemicals.

Respiratory Irritation

PDB particles and gas can be inhaled deep into the lungs. This causes inflammation and irritation of the bronchial tubes and airways. Coughing fits and breathing difficulty can result.

Eye & Skin Irritation

Contact exposure with solid PDB mothballs and vapours produces redness, swelling, itching, and burns on the eyes and skin. PDB is absorbed rapidly through the corneas and epidermis.

Reproductive System Toxicity

High level mothball exposure may have toxic effects on the reproductive system. Studies on rats found reduced fertility, sperm abnormalities, and smaller litter sizes.

Neurological Impacts

Research indicates PDB mothballs may contribute to decreased cognitive function, impaired motor skills, and reduced nerve conductivity from inhalation exposure.

Carcinogenic Effects

While not definitively proven in humans yet, PDB is classified as a suspected carcinogen by the EPA. Mothball exposure has been linked to higher cancer rates in rodent studies.

As you can see, PDB is some seriously nasty stuff. And remember - these toxic effects are from normal exposure to PDB in mothballs that people use routinely in their homes! Now let’s examine the dangers of the other chemical mothball variety.

The Health Hazards of Naphthalene Exposure

Naphthalene, the other go-to chemical for mothballs and repellents, may be even more concerning than PDB due to additional risks:


One of the most common side effects of naphthalene exposure is hemolytic anaemia. This is due to the chemical damaging red blood cells resulting in inflammation and abnormal breakdown. Symptoms include jaundice, fever, weakness, and fatigue.

Neurological Symptoms

Headaches, lack of coordination, confusion, and convulsions have occurred in those exposed to high levels of naphthalene. Permanent neurological damage is possible.

Bladder & Kidney Issues

The kidneys work hard to remove naphthalene from the body, which can lead to bladder irritation, kidney inflammation, and increased urine production. Colic and kidney stones are also possible risks.

Nausea & Diarrhea

Much like PDB, naphthalene ingestion causes stomach and intestinal problems, resulting in cramping, abdominal pain, nausea, vomiting, and diarrhea.

Liver Damage

The liver bears the brunt of naphthalene detoxification. Prolonged exposure can lead to jaundice and impaired liver function. Studies found liver lesions in animals exposed to naphthalene.

Respiratory Distress

Inhaling naphthalene vapours causes immediate injury to airway cells along with fluid buildup and inflammation in the lungs. Wheezing, chest tightness, and labored breathing can result.

Cancer Risks

While the EPA lists naphthalene as “possibly carcinogenic” there is reasonable evidence it can cause nasal and lung tumors, especially at high doses.

As you can see, both PDB and naphthalene mothballs present concerning toxicity issues that should make people think twice about using them. And those are just the health effects on humans...these chemicals also wreak havoc on the environment.

The Environmental Impact of Chemical Mothballs

In additional to harming your family’s health, traditional chemical mothballs also persistently contaminate the surrounding environment:

Air Pollution

The fumes from mothball chemicals linger in the air, spreading far beyond just the areas they are placed. This contributes to poorer overall outdoor and indoor air quality.

Soil Contamination

PDB and naphthalene residues accumulate in the soil surrounding homes where they are used. They can persist in soil for years before finally degrading or being leached deeper.

Water Pollution

Chemical mothball compounds frequently leach into ground and surface waters. They have been detected in samples from wells, lakes, and streams near urban areas.

Harmful to Wildlife

The non-targeted toxicity of mothball pesticides can harm birds, fish, beneficial insects, and other wildlife around the home. The chemicals spread through the food chain.

Kills Non-Target Insects

In addition to moths, mothballs are highly toxic to numerous beneficial species like honey bees, lady bugs, butterflies and more. Local ecosystems suffer.

Indoor Air Contamination

PDB and naphthalene vapours become trapped and concentrated inside enclosed spaces. This leads to prolonged indoor air pollution and greater risk for inhabitants.

Difficult Removal

Remediating mothball-contaminated soil or water is challenging. The chemicals are not biodegradable and require special processing for safe removal.

The takeaway is that the toxic substances in traditional mothballs don’t just conveniently disappear after use. They persistently infiltrate and pollute the local environment with consequences for both wildlife and humans.

Added Dangers of Mothball Misuse

Using mothballs incorrectly can make them even more hazardous. Some risky practices to avoid include:

  • Using too many mothballs for the space
  • Placing mothballs on surfaces or out in the open
  • Storing them in occupied rooms or porous containers
  • Putting mothballs near flames, stoves, or heat sources
  • Allowing children access to mothballs
  • Grinding up or cutting open mothballs
  • Mixing mothball chemicals together

All of these situations concentrate or expose people and pets to higher doses of the toxic chemicals. For example, cutting or grinding mothballs releases higher levels of concentrated fumes. Excess heat can also accelerate release of the hazardous vapours. Misuse raises both acute and long-term risks.

Symptoms of Mothball Poisoning

Hopefully the multitude of dangers associated with chemical mothballs is becoming clear. But what should you watch for if you suspect exposure to mothball toxicity? Here are common signs of mothball poisoning:

  • Headaches, dizziness, lightheadedness
  • Nausea, vomiting, diarrhea
  • Cough, sore throat, eye irritation
  • Difficulty breathing, fluid in the lungs
  • Fatigue, weakness, anaemia
  • Impaired cognition or coordination
  • Red skin rashes or burns
  • Abdominal pain or jaundice

If mothball poisoning is caught early, removal from exposure can allow recovery with no permanent effects. But chronic exposure raises the specter of lasting neurological, respiratory, liver and kidney damage. Seek immediate medical help if poisoning is suspected.

So just how dangerous are different mothball formulations? Let’s compare the acute toxicity next.

Comparing the Acute Toxicity of Naphthalene & PDB

While both chemicals are hazardous, naphthalene is generally more acutely toxic compared to PDB in animal studies:

Oral LD50

Naphthalene - 490 mg/kg body weight

PDB - 4,000 mg/kg

Dermal LD50

Naphthalene - 2 g/kg body weight

PDB - 10 g/kg

Inhalation LC50

Naphthalene - 170 ppm over 4 hrs

PDB - 200 ppm over 2 hrs

These LD50 and LC50 numbers represent the doses required to kill 50% of a sample population. The lower the value, the more toxic the chemical.

As you can see, naphthalene is significantly more dangerous than PDB via ingestion or skin contact. The vapours are also more acutely toxic when inhaled in high concentrations. However, chronic low doses of either chemical accumulate over time with damaging effects.

Legal Restrictions Around Chemical Mothballs

Given the extensive risks, certain regions have taken legal steps to restrict PDB, naphthalene, and other hazardous mothball formulas:

  • USA – Banned in California and Rhode Island. Other states restrict mothball usage.
  • Canada – Banned throughout Canada under the Pest Control Products Act.
  • Australia – Both naphthalene and PDB mothballs are completely banned.
  • EU – PDB is banned, mothballs with naphthalene still allowed in some countries.

So while still available in many areas, the most hazardous mothball formulations face regulatory pressure due to their health and environmental impacts. But even where legal, why gamble with your family’s safety when natural alternatives exist?

Safer Moth Prevention Alternatives

The good news is there are safer, non-toxic ways to effectively ward off moths without resorting to hazardous chemicals like naphthalene and PDB. Some great options include:

Cedarwood – Natural cedar repels moths with pleasant cedar oil instead of synthetics. Use cedar blocks, chips, or in closets.

Essential Oils – Oils like lavender, eucalyptus, and mint deter moths naturally. Use in sachets or diffusers.

Storage Containers – Seal clothing and textiles in airtight plastic or glass containers to exclude moths.

Inert Dusts – Mineral dusts like diatomaceous earth kill larvae but are harmless to people.

Freezing – Storing fabrics sealed in bags in below 0°F freezers for a few days can eliminate larvae and eggs.

Cleaning – Vacuuming and washing fabrics regularly removes larval infestations before they spread.

Traps – Pheromone or sticky traps draw in and catch moths without toxins.

Simple solutions like maintaining cleanliness, using natural aromatics, and keeping fabrics sealed can protect clothes without risky chemicals. You can moth-proof your home safely.


After reviewing all the hazards posed by traditional chemical mothballs, one thing is clear – these toxic relics have no place around your family or home. The temporary moth deterrence is nowhere near worth the risks of long-term health issues, environmental damage, and contamination of your living space. There are far safer, non-toxic ways to protect your valuables from fabric pests.

Rather than inhaling hazardous fumes, try cedar blocks, essential oils, freezing, traps, and other methods to send moths packing without harming yourself or the planet. Take control over moth infestations using smart prevention and natural solutions. With a little diligence, you can finally say goodbye to toxic mothball chemicals for good!

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Our mission is to empower you with the knowledge to curate a wardrobe that not only reflects your personal style but also aligns with environmentally friendly practices. From exploring the wonders of natural mothballs and sustainable garment storage to diving deep into DIY solutions and green living, we're here to guide you on a journey towards a more eco-conscious, stylish, and intentional lifestyle.

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