Are all molds harmful?

There are over 100,000 known species of mold, and the effects they have on humans is poorly understood. We do know that there are certain species that have been linked to adverse health effects in healthy humans. Molds can be allergenic, toxigenic, and carcinogenic in certain individuals. Most people tolerate exposure to normal mold levels without any adverse health effects, while others may have severe allergic reactions to the slightest amounts. While the research is limited, it has become apparent that individuals with suppressed or compromised immune systems may be at the greatest risk of developing a mold related illness.