|MadSci Network: Microbiology|
Your inquiry reminds me of the statement, "The adult human body contains an average 1 X 10^14 cells, fewer than 10% of which belong to you..." The remaining critters fall into hundreds of microbial species, mostly bacterial, many of which have never been cultured or characterized. Most live in the colon, but significant numbers can be found throughout the GI tract, in the genitourinary system, and on the skin. Within this collection you could probably find a microbe affected by EM radiation. Certainly, considering light as EM waves, you, or anyone else, comes in contact with photosynthetic bacteria in water or soil - bluegreen algae, for instance. However, such organisms are not a common, or generally permanent, component of our flora. Magnetospirillum is the only organism I know offhand that dramatically responds to a magnetic field. It primarily lives in sediments.
As for formaldehyde gas, it is a universally toxic agent. Formaldehyde causes cellular components to "cross-link" or stick together. With sufficient exposure, a cell, bacterial or not, will die.
Hope this helps... love the show.
Lynn Bry, MD/PhD
Department of Pathology
Brigham & Women's Hospital
Try the links in the MadSci Library for more information on Microbiology.