Typically, mold is not harmful, but exposure to high levels can cause symptoms that mimic a common cold. Mold can also trigger allergies or asthma symptoms in some people.
Molds are microscopic fungi that grow everywhere, both outdoors and indoors. They’re a natural part of our environment and thrive in areas with moisture.
Molds spread by releasing spores. We’re exposed to mold when we inhale these spores.
If you’re concerned about the health effects of mold, you might wonder how long it takes to get sick from mold exposure.
There isn’t a one-size-fits all answer, however. The time it takes for symptoms to start depends on many factors, including your environment and overall health.
Let’s discuss these factors, as well as the health effects related to mold.
The short answer: It depends. A reaction to one-time mold exposure can be immediate or delayed. Some people develop no symptoms at all.
Many factors determine the time it takes for mold to affect your health. To get a better idea of timing, consider the following factors:
Allergies and sensitivities
Everyone reacts to mold differently. Your personal sensitivity to mold will influence how quickly you develop symptoms.
If you have a mold allergy, your immune system thinks certain mold spores are invaders, or allergens. So, when you inhale spores, your body reacts by triggering sneezing or nasal congestion. This can happen immediately or after exposure, depending on your body.
If you don’t have a mold allergy, a one-time exposure may cause no symptoms. But sometimes, it can cause symptoms even if you’re not allergic. Again, it’s different for each person.
Amount of mold
The amount of mold also determines how long it takes for symptoms to start.
Generally, large amounts of mold are more likely to cause negative health effects. Therefore, the more mold is present, the more likely you are to develop symptoms quickly.
However, this also depends on your body. For some people, a one-time exposure to a small amount of mold isn’t enough to cause symptoms. But for people who are sensitive to mold, even a small amount can quickly trigger symptoms.
Duration of exposure
Similarly, the duration of the one-time mold exposure matters. After all, the longer you’re exposed to mold, the more spores you will inhale. This increases your overall exposure.
If exposure only lasts a few seconds or minutes, you may not have symptoms. But if you’re exposed to mold for a long time, your symptoms might develop rapidly. Again, it comes down to your level of sensitivity.
Proximity to mold
It also depends on how close you are to the mold. That’s because proximity affects how much mold you’re exposed to.
For example, you’re more likely to develop symptoms quickly if you directly handle mold. This can happen during activities like cleaning or touching moldy items.
If you’re allergic or sensitive to mold, it’s important to avoid direct contact with mold as much as possible.
The side effects of short-term mold exposure are different for each person. You’re more likely to have severe symptoms if you’re allergic or sensitive to mold.
In general, symptoms include:
- sinus and nasal congestion
- nasal irritation
- itchy, watery eyes
- red eyes
- blurry vision
- trouble breathing
- sore throat
- skin irritation, like rashes or hives
- asthma attacks (if you have asthma)
Who’s most at risk for developing symptoms from mold exposure?
Some people are more likely to get sick from mold exposure. This includes:
- pregnant people
- people with chronic respiratory conditions, like asthma
- people with allergies
- older people
- people with conditions that weaken the immune system, like HIV or cancer
Over time, repeated mold exposure can cause more severe effects. This may include:
- increased risk of upper and lower respiratory symptoms
- chronic sinusitis
- organ damage
- Legionnaire’s disease
- development of mold allergy
- development of asthma (in children)
Black mold, or Stachybotrys atra, has a reputation for being fatal. This is due to reports that black mold was related to infant deaths in the 1990s. It’s also been linked to the idea of “sick building syndrome” and is often called “toxic black mold.”
But there’s no solid evidence proving that black mold is toxic. Black mold, and mold in general, is not deadly.
Still, black mold can cause unwanted side effects, especially those in people who are sensitive to mold. This includes people who are young, old, or have compromised immune systems.
Visit a doctor if you have:
- persistent sinus and nasal congestion
- frequent headaches
- chronic coughing or sneezing
- difficulty breathing
- frequent nosebleeds
- unexplained skin irritation
- more frequent asthma attacks
Sometimes, it can be difficult to know if mold is causing your symptoms. Many side effects of mold exposure are similar to other conditions, like seasonal allergies. Some symptoms also take time to appear.
Your best bet is to see a doctor, even if you’re unsure your symptoms are related to mold. They can help you find relief.
The best way to treat mold exposure symptoms is to reduce exposure. Follow these tips:
- Avoid contact with moldy items or surfaces.
- Avoid damp rooms, like basements.
- Remove mold from the home by cleaning surfaces and drying damp areas.
- Increase ventilation by using a fan or opening windows.
- Reduce indoor humidity with a dehumidifier.
The length of time it takes for mold to leave your body will depend on your level of previous exposure.
In addition to reducing mold exposure, your doctor might recommend over-the-counter (OTC) allergy medicine.
If your symptoms are mild, you might be able to take the medication whenever your symptoms are bothersome. But if you have moderate or severe symptoms, you might need to take them daily. Your doctor might also suggest prescription allergy medicine.
The following are tell-tale signs of a mold problem in the home:
- a musty, earthy odor
- black, green, gray, or white splotches
- spots that get bigger
- discolored grout between tiles
If you find a moldy area that’s smaller than 3 square feet, it’s possible to clean it yourself. But if it’s any bigger, the Environmental Protection Agency recommends getting help from a professional.
A water damage restoration service can provide professional mold cleaning. You can find a local company by searching for “water damage restoration service near me” online.
The length of time it takes for mold to cause symptoms varies greatly. The side effects can be immediate, delayed, or nonexistent. It depends on your environment and level of mold sensitivity.
Other factors to consider include the duration of exposure and the amount of mold. Direct contact with mold can also cause more severe symptoms.
The best way to minimize mold symptoms is to reduce your exposure. If your symptoms persist, see a doctor.