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Is Black Mold Dangerous? What the CDC and EPA Say

AirQualitySource Editorial Team · Published September 14, 2026 · Updated September 14, 2026 · 3 min readResearched and written with AI assistance, reviewed by our editorial team against primary sources. Every quote links to its source. Editorial standards

This article reports what public health agencies say about black mold, quoted and linked. It is not medical advice. If you have health symptoms, talk to a doctor.

The short answer from the agencies: "black mold" usually refers to Stachybotrys chartarum. The CDC says there is no test that proves a link between it and particular health symptoms, and that you do not need to know whether you have it — because the advice is the same for every mold. In the CDC's words: "All molds should be treated the same with respect to potential health risks and removal."1

What is "black mold"?

The mold people usually mean is Stachybotrys chartarum. The CDC describes it as "a greenish-black mold."2 It grows on materials high in cellulose, "such as fiberboard, gypsum board, and paper,"3 and "constant moisture is required for its growth."4

Color alone does not tell you what kind of mold you have, and the agencies say you don't need to find out (more on that below).

What is and isn't proven

The "toxic mold" question

Molds can produce more than one kind of substance. The EPA says molds produce "allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins)."5

The CDC's fact sheet addresses one specific concern — whether black mold causes bleeding in the lungs of infants. Its answer: "a possible association between acute idiopathic pulmonary hemorrhage among infants and Stachybotrys chartarum has not been proven."6

More broadly, the CDC says: "At present, no test exists that proves an association between Stachybotrys chartarum and particular health symptoms."7 It adds that black mold "and other molds may cause health symptoms that are nonspecific."8

Health effects the agencies do describe

The agencies describe health effects of mold in general, not black mold specifically:

  • Effects vary. The CDC: exposure to damp and moldy environments "may cause a variety of health effects, or none at all."9
  • Common symptoms. "For some people, mold can cause a stuffy nose, sore throat, coughing or wheezing, burning eyes, or skin rash."10
  • Allergies. The EPA describes allergic responses including "hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis)."11
  • Irritation. Mold exposure "can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people."12
  • People at higher risk. "People with asthma or who are allergic to mold may have severe reactions."13 And "immune-compromised people and people with chronic lung disease may get infections in their lungs from mold."14
  • What else is reported. The EPA: "Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold."15

The CDC also points to a 2004 review by the Institute of Medicine, which "found there was sufficient evidence to link indoor exposure to mold with upper respiratory tract symptoms, cough, and wheeze in otherwise healthy people; with asthma symptoms in people with asthma; and with hypersensitivity pneumonitis in individuals susceptible to that immune-mediated condition."16

Where the agencies agree: remove it, whatever it is

On what to do, the advice is consistent:

  • The CDC: "if Stachybotrys chartarum or other molds are found in a building they should be removed."17
  • The CDC: "It is not necessary to determine what type of mold you may have growing in your home or other building."18
  • Texas's mold licensing agency says the same, noting that "it is not necessary to identify the species of mold growing in a residence, and the Centers for Disease Control (CDC) does not recommend routine sampling for molds."19

Can a test tell me if my mold is dangerous?

Not according to the CDC: "The health effects of mold are different for different people so you cannot rely on sampling and culturing to know whether someone might become sick."20 There is also no federal limit to compare a result against — the EPA notes that "no EPA or other federal limits have been set for mold or mold spores."21

For the situations where testing can help, see Do you need a mold test?

If you have symptoms

The CDC says: "Individuals with persistent symptoms should see their physician."22 The EPA's guidance likewise says that "for more detailed information consult a health professional."23

What to do about the mold

The next steps are the same for black mold as for any other: stop the moisture, then clean it up or get help. See Found mold in your house? What to do first and Can you remove mold yourself?

Sources reviewed for this article

Each number in the article points to the exact passage below. We read every page on the date shown and checked that each quote appears on it word for word.

  1. 1.“All molds should be treated the same with respect to potential health risks and removal.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  2. 2.“Stachybotrys chartarum is a greenish-black mold.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  3. 3.“It can grow on material with a high cellulose content, such as fiberboard, gypsum board, and paper.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  4. 4.“Constant moisture is required for its growth.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  5. 5.“Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins).”US Environmental Protection Agency, A Brief Guide to Mold, Moisture and Your Home. Accessed September 14, 2026.
  6. 6.“To date, a possible association between acute idiopathic pulmonary hemorrhage among infants and Stachybotrys chartarum has not been proven.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  7. 7.“At present, no test exists that proves an association between Stachybotrys chartarum and particular health symptoms.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  8. 8.“Stachybotrys chartarum and other molds may cause health symptoms that are nonspecific.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  9. 9.“Exposure to damp and moldy environments may cause a variety of health effects, or none at all.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  10. 10.“For some people, mold can cause a stuffy nose, sore throat, coughing or wheezing, burning eyes, or skin rash.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  11. 11.“Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis).”US Environmental Protection Agency, A Brief Guide to Mold, Moisture and Your Home. Accessed September 14, 2026.
  12. 12.“In addition, mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people.”US Environmental Protection Agency, A Brief Guide to Mold, Moisture and Your Home. Accessed September 14, 2026.
  13. 13.“People with asthma or who are allergic to mold may have severe reactions.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  14. 14.“Immune-compromised people and people with chronic lung disease may get infections in their lungs from mold.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  15. 15.“Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold.”US Environmental Protection Agency, A Brief Guide to Mold, Moisture and Your Home. Accessed September 14, 2026.
  16. 16.“In 2004 the Institute of Medicine (IOM) found there was sufficient evidence to link indoor exposure to mold with upper respiratory tract symptoms, cough, and wheeze in otherwise healthy people; with asthma symptoms in people with asthma; and with hypersensitivity pneumonitis in individuals susceptible to that immune-mediated condition.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  17. 17.“However, if Stachybotrys chartarum or other molds are found in a building they should be removed.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  18. 18.“It is not necessary to determine what type of mold you may have growing in your home or other building.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  19. 19.“Generally, it is not necessary to identify the species of mold growing in a residence, and the Centers for Disease Control (CDC) does not recommend routine sampling for molds.”Texas Department of Licensing and Regulation, Mold Assessors and Remediators FAQs. Accessed September 14, 2026.
  20. 20.“The health effects of mold are different for different people so you cannot rely on sampling and culturing to know whether someone might become sick.”Centers for Disease Control and Prevention, Mold. Accessed September 14, 2026.
  21. 21.“Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards.”US Environmental Protection Agency, Mold Testing or Sampling. Accessed September 14, 2026.
  22. 22.“Individuals with persistent symptoms should see their physician.”Centers for Disease Control and Prevention, Facts About Stachybotrys chartarum. Accessed September 14, 2026.
  23. 23.“For more detailed information consult a health professional.”US Environmental Protection Agency, A Brief Guide to Mold, Moisture and Your Home. Accessed September 14, 2026.

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