Abstract by Peter Van Katwyk
Peter Van Katwyk
Hawaiian clays that house Mycobacterium
The purpose of the research is to identify the minerals found in soils from the Hawaiian Islands in order to predict which soils contain minerals that can house Mycobacterium. This genus can cause several respiratory illnesses. Testing these samples allows us to identify which of two clay minerals (halloysite or kaolinite) is more likely to be associated with Mycobacterium. Using X-ray diffraction, we characterized the clays in 46 soil samples. The tests were run with and without formamide, which expands the structure of halloysite, but not kaolinite, allowing us to measure the clay proportions in each soil. From the 46 samples, 41 samples were 100% kaolinite. Five samples, all of which came from Oahu, contained halloysite. Of these 5 samples, 2 contained more than 70% Halloysite and the other 3 contained less than 50%. A recent study from Kohala (Big Island), which has a young substrate (0.3 Ma), solely contained halloysite. This suggests that halloysite recrystallizes over time to kaolinite as evidenced by the older, Oahu (>2 Ma) soils. Soil culture results for Mycobacterium conducted at National Jewish Health Center will be examined for the presence of this genus.