It seems that women (and men) who were flight attendants in the earlier decades of intercontinental air travel are developing Parkinsons disease, a neurological disorder of the muscles (tremors, stiffness, increasingly limited movement). Those assigned to return flights from tropical countries were instructed to spray airplane cabins with insecticides, a practice that continued into the 1990s. Chemical exposure, especially in tight, unventilated areas (e.g., airplane cabins) can have devastating long-term effects on the body. Former stewardesses are filing lawsuits against the airlines they worked for. Read more here and here and here.
The 1950s brought us state-sponsored spraying of DDT to combat the spread of polio and infantile paralysis. See the news footage below, showing children sprayed with clouds of the stuff while eating lunch and bathing in swimming pools.