Yes. Certain types of molds can produce toxins called mycotoxins. Mycotoxins are toxic chemical substances and can induce liver cancer and kidney failure, as well as affect the brain or nervous system.

Mycotoxins are not always produced. This depends on what the mold is growing on, temperature, pH, humidity, and other unknown factors. When mycotoxins are present, they occur in both living and dead mold spores and can be found in materials that have become contaminated with molds.