X-ray films are made with light, developer solution, fixer and rinse water.
Used X-rays are made of a polyester film coated in emulsion layers made of gelatin and contain silver. All X-ray film contains about 2 percent of its weight in silver after processing. Extracting silver from X-rays can be done in several ways and helps offset disposal costs.
Benefits
This heavy metal is a valuable resource for manufacturing and economic trade. Recovering the silver from used film helps keep it in the marketplace and out of the landfills, serving as an economic boost and helping the environment. Its sale can help hospitals and recyclers reduce the cost of disposal, earn extra income and lower the overall costs of producing X-rays.
Methods
There are several methods for extracting silver from X-rays. The most common method in past years was simply burning shredded X-rays to destroy the film, while leaving behind the precious metal. Modern facilities use environmentally friendly methods such as, metal replacement, electroplating and chemical precipitation. Researchers have also developed methods of silver extraction using bacteria and enzymes to eat away at the gelatin emulsion, leaving the silver for recovery. This method is not widely used (as of 2011).
Regulations
The Environmental Protection Agency (EPA) and the Health Insurance Portability and Accountability Act (HIPAA) require silver recyclers, hospitals and clinics to follow certain rules regarding X-ray film disposal. The film is considered private information and must be completely destroyed, while the silver and other chemicals within the film are toxic to the environment. Silver recovery prevents the metal from entering the environment, but other products used in the process must be carefully contained or destroyed.
Tags: silver from, from X-rays, silver from X-rays, X-ray film