Over the last century, radiation injuries and the nature of radiation itself have been vigorously studied as a result of its expanding role in our society. Today, radionuclides are used for a wide variety of medical and nonmedical purposes ranging from detecting smoke to diagnostic testing to powering spacecraft. Although useful, radionuclides can present a danger to humans both through their metallic nature and through the process of radioactive decay. This ionizing radiation may cause injury to multiple cellular structures and critical molecules, such as DNA, resulting in mutations, neoplasms, or cell death. The particles of radiation, their sources, and the mechanisms by which they pose a health risk are the subjects of the following discussion.
Radiation became a concern for scientists as a toxin only a year following the discovery of x-rays by Wilhelm Roentgen in 1895.91 Soon after, Thomas Edison reported corneal injuries in several of his workers conducting experiments using his newly invented x-ray generator. Eight years later, Clarence Dally, one of Edison's most dependable assistants, became the first radiation-related death in the United States.32 Fortunately, the medical community recognized the utility of Edison's fluoroscope and began to use x-ray machines to help diagnose various illnesses. For example, the British army developed and used mobile x-ray machines to find bullets and shrapnel in wounded soldiers in Sudan in the early 1900s.
Over the next 10–15 years, radioactive substances also found their way into society as objects of fascination and as a means of alternative medical therapies. Aggressively marketed as "cure-alls," advertisements for products such as the Revigator and Radithor enticed people to drink water "charged" with radon or radium. These products ushered in 20 years of "health" products containing radioactive materials.60,61
In 1915, the British Roentgen Society, recognizing the potential hazards of radiation, proposed standards for radiation protection of workers, which included shielding, restricted work hours, and medical examinations. Unfortunately, no dose limits were implemented because dose quantitation was unavailable.
The opening of the Radium Luminous Materials Corporation in Orange, New Jersey, in 1917 represented the first of several companies to profit from the novelty and popularity of the bluish glow of radium. In an industry that employed over 4000 workers at its peak, nearly all of whom were women, the radium was hand-painted onto watch and instrument dials. These young women were instructed to obtain a fine tip on their paintbrushes using a technique called "lip pointing," which meant using their lips and tongues to shape their paintbrushes. Unaware of the danger, some of these women also painted their nails, lips, and eyelids with the radioactive paint. By 1927, about 100 of them died from osteosarcoma of the jaw, brain tumors, and developed other noncancerous lesions of the mouth, all related to radium exposure.63,74
The only occasions nuclear bombs were used against humans occurred in August 1945 when the United States dropped ...