Site cleanup Anthrax spores can survive for very long periods of time in the environment after release. Chemical methods for cleaning anthrax-contaminated sites or materials may use
oxidizing agents such as
peroxides,
ethylene oxide, Sandia Foam, chlorine dioxide (used in the
Hart Senate Office Building), peracetic acid, ozone gas, hypochlorous acid, sodium persulfate, and liquid bleach products containing sodium hypochlorite. Nonoxidizing agents shown to be effective for anthrax decontamination include methyl bromide, formaldehyde, and metam sodium. These agents destroy bacterial spores. All of the aforementioned anthrax decontamination technologies have been demonstrated to be effective in laboratory tests conducted by the US EPA or others. Decontamination techniques for
Bacillus anthracis spores are affected by the material with which the spores are associated, environmental factors such as temperature and humidity, and microbiological factors such as the spore species, anthracis strain, and test methods used. A bleach solution for treating hard surfaces has been approved by the EPA.
Chlorine dioxide has emerged as the preferred biocide against anthrax-contaminated sites, having been employed in the treatment of numerous government buildings over the past decade. Its chief drawback is the need for
in situ processes to have the reactant on demand. To speed the process, trace amounts of a nontoxic
catalyst composed of iron and tetroamido macrocyclic
ligands are combined with
sodium carbonate and
bicarbonate and converted into a spray. The spray formula is applied to an infested area and is followed by another spray containing
tert-butyl hydroperoxide. Using the catalyst method, complete destruction of all anthrax spores can be achieved in under 30 minutes. Cleanup of anthrax-contaminated areas on ranches and in the wild is much more problematic. Carcasses may be burned, though often 3 days are needed to burn a large carcass and this is not feasible in areas with little wood. Carcasses may also be buried, though the burying of large animals deeply enough to prevent resurfacing of spores requires much manpower and expensive tools. Carcasses have been soaked in formaldehyde to kill spores, though this has environmental contamination issues. Block burning of vegetation in large areas enclosing an anthrax outbreak has been tried; this, while environmentally destructive, causes healthy animals to move away from an area with carcasses in search of fresh grass. Some wildlife workers have experimented with covering fresh anthrax carcasses with shadecloth and heavy objects. This prevents some scavengers from opening the carcasses, thus allowing the putrefactive bacteria within the carcass to kill the vegetative
B. anthracis cells and preventing sporulation. This method also has drawbacks, as scavengers such as hyenas are capable of infiltrating almost any exclosure. The experimental site at
Gruinard Island is said to have been decontaminated with a mixture of formaldehyde and seawater by the Ministry of Defence. It is not clear whether similar treatments had been applied to US test sites.
Biological warfare giving a
presentation to the United Nations Security Council, holding a model vial of supposed weaponized anthrax Anthrax spores have been used as a
biological warfare weapon. Its first modern incidence occurred when Nordic rebels, supplied by the
German General Staff, used anthrax with unknown results against the
Imperial Russian Army in Finland in 1916. Anthrax was first tested as a biological warfare agent by
Unit 731 of the Japanese Kwantung Army in
Manchuria during the 1930s; some of this testing involved intentional infection of prisoners of war, thousands of whom died. Anthrax, designated at the time as Agent N, was also investigated by the Allies in the 1940s. In 1942, British scientists at
Porton Down began research on
Operation Vegetarian, an ultimately unused
biowarfare military operation plan which called for animal feed pellets containing
linseed infected with anthrax spores of the
Vollum-14578 strain to be dropped by air over the countryside of
Nazi Germany. The pellets would be eaten by cattle, which would in turn be eaten by the human population and as such severely disrupt the German war effort. In the same year, bioweapons tests were carried out on the uninhabited
Gruinard Island in the
Scottish Highlands, with Porton Down scientists studying the effect of anthrax on the island's population of sheep. Ultimately, five million pellets were created, though plans to drop them over Germany using
Royal Air Force bombers in 1944 were scrapped after the success of
Operation Overlord and the subsequent Allied liberation of France. All pellets were destroyed using incinerators in 1945. Weaponized anthrax was part of the US stockpile prior to 1972, when the United States signed the
Biological Weapons Convention. President
Nixon ordered the dismantling of US biowarfare programs in 1969 and the destruction of all existing stockpiles of bioweapons. In 1978–79, the
Rhodesian government used anthrax against cattle and humans during its campaign against rebels. The Soviet Union created and stored 100 to 200 tons of anthrax spores at
Kantubek on
Vozrozhdeniya Island; they were abandoned in 1992 and destroyed in 2002.
American military and
British Army personnel are no longer routinely vaccinated against anthrax prior to active service in places where biological attacks are considered a threat. Extensive cover-ups and destruction of records by the
KGB continued from 1979 until Russian president
Boris Yeltsin admitted this anthrax accident in 1992.
Jeanne Guillemin reported in 1999 that a combined Russian and United States team investigated the accident in 1992. Nearly all of the night-shift workers of a ceramics plant directly across the street from the biological facility (compound 19) became infected, and most died. Since most were men, some
NATO governments suspected the Soviet Union had developed a sex-specific weapon. The government blamed the outbreak on the consumption of anthrax-tainted meat, and ordered the confiscation of all uninspected meat that entered the city. They also ordered all
stray dogs to be shot and people not have contact with sick animals. Also, a voluntary evacuation and anthrax vaccination program was established for people from 18 to 55. To support the
cover-up story, Soviet medical and legal journals published articles about an outbreak in livestock that caused gastrointestinal anthrax in people having consumed infected meat, and cutaneous anthrax in people having come into contact with the animals. All medical and public health records were confiscated by the KGB. In 1992, President Yeltsin admitted he was "absolutely certain" that "rumors" about the Soviet Union violating the 1972 Bioweapons Treaty were true. The Soviet Union, like the US and UK, had agreed to submit information to the UN about their bioweapons programs, but omitted known facilities and never acknowledged their weapons program. To make large amounts of an
aerosol form of anthrax suitable for biological warfare requires extensive practical knowledge, training, and highly advanced equipment. Concentrated anthrax spores were used for bioterrorism in the
2001 anthrax attacks in the United States, delivered by mailing postal letters containing the spores. The letters were sent to several news media offices and two Democratic senators:
Tom Daschle of South Dakota and
Patrick Leahy of Vermont. As a result, 22 were infected and five died. These events also spawned many
anthrax hoaxes. Due to these events, the US Postal Service installed
biohazard detection systems at its major distribution centers to actively scan for anthrax being transported through the mail. As of 2020, no positive alerts by these systems have occurred.
Decontaminating mail In response to the postal anthrax attacks and hoaxes, the United States Postal Service sterilized some mail using gamma
irradiation and treatment with a proprietary
enzyme formula supplied by Sipco Industries. A scientific experiment performed by a high school student, later published in the
Journal of Medical Toxicology, suggested a domestic
electric iron at its hottest setting (at least ) used for at least 5 minutes should destroy all anthrax spores in a common postal envelope. == Other animals ==