 United States Postal Service irradiated mail

United States Postal Service (USPS) irradiated mail refers to mail that has been treated with ionizing radiation as a method of disinfection. This process is used to eliminate potential biological threats, such as bacteria and viruses, particularly in the wake of events like the anthrax attacks in 2001. The irradiation process involves exposing mail to a controlled amount of gamma rays or electron beams, which kill pathogens and can also reduce the risk of contamination from harmful substances.