Not to gross you out but if you seem to catch a cold every-time you fly, this will be useful information. A couple of new studies are out on the dirtiest parts of airplane. Marketplace did one study that showed seat pockets are a petri dish of of mold, coli form, and E.coli. Tray tables had high levels of bacteria and seat belts show high levels of bacteria and yeast. Airplane cleaning isn't regulated by either the FAA or OSHA so the cleanliness of airplanes is left to the discretion of airlines which are often booking too tightly for a cleaning between flights. Check out our conversation and the unnamed flight attendant who weighs in on the dirtiest part of the plane.