Complications from ARS include an increased risk of developing radiation-induced cancer later in life. According to the controversial but commonly applied linear no-threshold model, any exposure to ionizing radiation, even at doses too low to produce any symptoms of radiation sickness, can induce cancer due to cellular and genetic damage. The probability of developing cancer is a linear function with respect to the effective radiation dose. Radiation cancer may occur after ionizing radiation exposure following a latent period averaging 20 to 40 years. History
Acute effects of ionizing radiation were first observed when Wilhelm Röntgen intentionally subjected his fingers to X-rays in 1895. He published his observations concerning the burns that developed that eventually healed, and misattributed them to ozone. Röntgen believed the free radical produced in air by X-rays from the ozone was the cause, but other free radicals produced within the body are now understood to be more important. David Walsh first established the symptoms of radiation sickness in 1897.Ingestion of radioactive materials caused many radiation-induced cancers in the 1930s, but no one was exposed to high enough doses at high enough rates to bring on ARS. The atomic bombings of Hiroshima and Nagasaki resulted in high acute doses of radiation to a large number of Japanese people, allowing for greater insight into its symptoms and dangers. Red Cross Hospital Surgeon Terufumi Sasaki led intensive research into the syndrome in the weeks and months following the Hiroshima and Nagasaki bombings.
A New York City firefighter developed eosinophilic pneumonia after inhalation of dust from the World Trade Center on September 11, 2001. Parasitic infections
Parasites cause eosinophilic pneumonia in three different ways. Parasites can either invade the lungs, live in the lungs as part of their life cycle, or be spread to the lungs by the bloodstream. Eosinophils then migrate to the lungs in order to fight the parasites, and cause eosinophilic pneumonia when they release their contents. Important parasites that invade the lungs include Paragonimus lung flukes and the tapeworms Echinococcus and Taenia solium. Important parasites which inhabit the lungs as part of their normal life cycle include the worms (helminths) Ascaris lumbricoides, Strongyloides stercoralis and the hookworms Ancylostoma duodenale and Necator americanus. When eosinophilic pneumonia is caused by helminths, it is often called "Löfflers syndrome". The final group of parasites cause eosinophilic pneumonia when their eggs are carried into the lungs by the bloodstream. This can include Trichinella spiralis, Strongyloides stercoralis, Ascaris lumbricoides, the hookworms, and the schistosomes. Acute and Chronic Eosinophilic Pneumonia
The causes for both acute and chronic eosinophilic pneumonia are unknown as of 2005. There is some suspicion that at least the acute form is the result of the bodys response to some unidentified environmental agent.