Aureobasidium
Aureobasidium is a common mold on damp painted surfaces, caulk and window frames. It is best known as a skin and respiratory allergen.
At a glance
- Appearance
- Pink/cream, darkening to brown-black
- Loves
- Damp window frames, caulk, painted surfaces
- Mycotoxins
- Not a notable mycotoxin producer
- Key action
- Reduce condensation; clean and dry surfaces
The short answer
Aureobasidium is a mold that starts pink or cream and darkens to brown-black, growing on damp window frames, caulk, grout and painted surfaces. It is a common allergen that can irritate skin, eyes and airways, but is not a notable mycotoxin producer. Reducing condensation and keeping surfaces dry controls it.
What is Aureobasidium?
A common mold of damp painted and caulked surfaces; recognized mainly as a skin and respiratory allergen.
Quick summary
- Common on damp window frames, caulk and paint.
- A skin and respiratory allergen.
- Not a notable mycotoxin producer.
- Condensation control keeps it away.
This information is educational and does not diagnose or treat any condition. It is not for emergencies. If you have trouble breathing, chest pain, fainting or other severe symptoms, call your local emergency number right away.
Where it grows
Aureobasidium often begins pink or cream-colored and darkens to brown or black with age. It favors damp window frames, silicone caulk, grout and painted walls where condensation collects.
Health context
It is a recognized allergen that can cause skin, eye and respiratory irritation in sensitized people. It is not considered an important mycotoxin producer, so its significance is allergic.
Controlling it
Wipe down and dry damp window frames and bathroom surfaces, improve ventilation, reduce condensation, and keep humidity in the 30–50% range. Replace deteriorated caulk where growth is embedded.
Key takeaways
- Aureobasidium favors damp painted and caulked surfaces.
- It is mainly a skin and respiratory allergen.
- Condensation control prevents it.
Frequently asked questions
What is the pink then black mold on my window caulk?
It is often Aureobasidium, which starts pale or pink and darkens with age. Reducing condensation, drying the area, and replacing embedded caulk usually resolves it.
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This article is for general education only and does not diagnose, treat or replace care from your own licensed clinician. MoldDetox.ai provides physician-supervised, educational health services. It does not provide emergency care. Testing and recommendations support — but do not replace — evaluation by your own licensed clinician.