Have you been exposed? That's a difficult question to answer. It's like asking how much sun it takes to cause sunburn. It varies from person to person. For some it takes very little exposure to cause an adverse reaction. I recently read an article about a little girl that could not be in direct sunlight. To do so would result in severe blistering. On the other hand, some people can be in the sun for long periods of time without any adverse reaction. Also, when someone is severely sunburned, he or she becomes more sensitive, in other words, it takes less exposure the next time to create the same reaction. Likewise, exposure to mold can make someone more sensitive to it. Once a person is removed from the exposure, the reactions tend to diminish. While sun is primarily a dermal exposure issue, with a potential for heat stress, adverse reactions to moldexposure can be dermal or internal due to ingestion or respiration. As a general rule, when you see mold the moisture problem needs to be resolved and the mold removed.