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Molds are a type of fungi, which can flourish both indoors and outside. There are millions of mold species.

Mold is important for the planet’s ecosystem, because it helps break down waste products and organic matter, such as leaves, dead trees, and garbage.

Some people get sick from exposure to mold. Others have no symptoms and don’t experience ill effects of any kind.

In this article, we’ll talk about the potential dangers of mold exposure, identify who’s most vulnerable, and provide solutions for keeping your environment mold-proof.

Mold needs organic matter to feed upon and moisture in order to grow. When growing conditions are right, mold releases spores and volatile organic compounds (VOCs) into the air, which may make some people feel sick.

Mold spores may be breathed in or absorbed through skin. Mold can also grow on food and may be hazardous if ingested.

Mold exposure outdoors

When you’re outside, you may come into contact with moldy surfaces in:

  • forests
  • beaches
  • backyards
  • playgrounds
  • sidewalks

Piles of wet leaves, damp wood, and rotted tree bark are all sources of mold. So are standing, stagnant water sources, such as wading pools and puddles.

Mold exposure indoors

Mold spores enter our homes, schools, and workplaces through a wide range of channels. They may attach themselves to clothing and shoes as well as to your pet’s coat. Spores can float in through open doors and windows and through air conditioning or heating vents.

Some of the most common varieties of indoor mold are Aspergillus, Cladosporium, and Stachybotrys atra, which is also known as black mold. Despite its negative reputation, black mold hasn’t been definitively linked to severe health issues.

Mold needs moisture to grow. Damp, humid environments are particularly prone to mold growth. Poorly ventilated areas also pose a mold risk.

Indoor areas that commonly become moldy include:

  • damp bathrooms or kitchens that have drippy faucets or leaking pipes
  • damp basements
  • damp carpet
  • wet paper
  • fireplace wood
  • damp ceiling tiles or drywall
  • potted plants
  • condensation on window sills
  • washing machines and dishwashers

Personal items, such as sponges, lunchboxes, thermoses, and sippy cups, can also harbor mold.

Mold on food

Certain mold species thrive on foodstuffs such as cereal, bread, nuts, and dried fruits. Some of these may contain toxic substances called mycotoxins.

According to the World Health Organization (WHO), mycotoxins can cause severe, adverse health effects, such as:

  • acute poisoning
  • immune deficiencies
  • cancer

People with certain health conditions may be more likely to experience symptoms, including infections and respiratory distress. These conditions include:

People with a mold allergy

If you’re allergic to mold, you may have more severe allergic reactions, plus secondary conditions, such as:

Infants, toddlers, and children

Infants, toddlers, and children may be particularly at risk. One 2011 study found that children who grew up in mold-infested homes had lower cognitive scores than their peers.

Another study indicated that early mold exposure increased the risk of acquiring asthma later on in life.

This finding has been substantiated in other research, including a National Institute of Health (NIH)-funded study, run by a team at the University of Cincinnati. This study found that the amount of mold in the home, as well as the type of mold, had an impact.

Researchers used the Environmental Relative Moldiness Index (ERMI) to measure how moldy each house was. This test analyzes dust to identify mold strains and quantity.

According to the study, the three species of mold most commonly associated with childhood asthma are Aspergillus ochraceus, Aspergillus unguis, and Penicillium variabile.

The children who lived in homes with high ERMIs during infancy had the highest rates of asthma by age 7.

Mold in the workplace

Some workplaces, such as poorly ventilated factories, greenhouses, and vineyards, may house large amounts of mold.

Any workplace that contains lots of old paper products, such as used book stores, may be a source of mold. Paper contains cellulose, an organic food source that certain mold species thrive upon. Old books that’ve been housed in humid conditions may be filled with millions of mold spores.

Farms and stables may also harbor large amounts of moldy hay. Mold toxins often develop in hay after a delayed harvest. Hay that contains mold is dangerous for humans to breathe in and for horses to eat.

Mold allergies are progressive. The more contact you have, the more likely you are to experience severe symptoms.

In some instances, no symptoms or only vague symptoms of mold exposure may occur. These can go unnoticed, especially in babies.

Even without immediate, noticeable symptoms, long-term health effects, such as asthma, have been associated with mold. It’s not currently known whether this is a direct cause of mold or merely an association.

Mold may cause:

  • skin irritation
  • sporotrichosis, a skin infection that starts out as a small pink, red, or purple bump on the skin
  • itchy, red eyes
  • runny or stuffy nose
  • postnasal drip
  • headache
  • dizziness
  • asthmatic symptoms, such as coughing, wheezing, shortness of breath, and tightness in the chest

If you or your child display symptoms of mold exposure, see your doctor.

Allergic reactions to mold may clear up with over-the-counter medications, such as antihistamines. If your allergies persist, you should also see your doctor.

Asthmatic symptoms require immediate medical attention.

Here are some tips for how to remove mold from your home and prevent exposure:

  • Check your home for places where mold might lurk, such as under sinks and in basement walls. Things to look for include visible mold growth, water leaks, and water seepage.
  • Promptly fix any leaks you find, including leaky roofs and pipes.
  • Dry damp surfaces, such as shower stalls, immediately after use.
  • Control your home’s humidity level with a dehumidifier.
  • Keep kitchens, bathrooms, and laundry rooms well ventilated.
  • If flooding occurs, clean and dry the flooded area as quickly as possible.

Since mold can grow under carpets and behind walls, moldy homes don’t always have obvious mold patches.

Mold smell is unmistakable but doesn’t always accompany mold. If you suspect that your home is harboring mold but can’t find the source, a home inspection will help.

Mold may cause health problems in some people but not affect others.

Mold exposure symptoms include allergic reactions and respiratory distress. Children and people with compromised immune systems may be particularly vulnerable to mold.

If you suspect that your home has mold, eliminating leaks, dampness, and humidity may help.