david strauss is a professor of microbiology and immunology at texas tech university. >> i spent about a half an hour in the house and i was talking with bill, mr. holder. and i said to him, turned to him and said, "bill, i don't feel very good." i said, "i got to get out of here." and just literally walked out the front door and pretty much collapsed. i lost any ability to stand without aid. >> the samples were processed at texas tech health sciences center. technicians there sterilized the slides, then examined them under a high-powered microscope. the cotton swab samples were transferred to petri dishes, then put in an incubator for five to seven days. if there were spores present, they would grow mold which could be examined under the microscope. most household molds are harmless. but dr. strauss found one type of mold in the home that was not harmless. it was a toxic, deadly mold known as stachybotrys. experts believed stachybotrys spores exist on many building materials. as long as those materials stay dry, the spores don't present a problem. but when the spores get wet, from a l