Gruinard Island: A Forgotten Testing Ground for Biological Weapons During World War II
Gruinard Island stretches approximately 2 kilometers long and is accessible via a short train ride from the Ross-shire coast in the Inner Hebrides, western Scotland. In the 20th century, aside from a few sheep and occasional visitors, the island was uninhabited, making it an ideal location for the British military’s first outdoor biological weapons experiments.
Gruinard Island (left) photographed from a safe distance in the Inner Hebrides, western Scotland. (Photo: PaulR1800/Flickr).
As World War II broke out, Britain grew increasingly concerned about the potential use of chemical weapons by Nazi Germany, who had pioneered the use of mustard gas in World War I and had developed the largest chemical industry in the world.
In response to this threat, scientists at Porton Down, the British military’s top-secret laboratory, were tasked with further investigating chemical and biological weapons. Anthrax, caused by the bacterium Bacillus anthracis, particularly captured their attention. This disease primarily affects livestock and wild animals but can also infect humans.
Upon inhalation, ingestion, or contact with anthrax spores, victims quickly experience high fever, chills, coughing, difficulty breathing, nausea, vomiting, excessive sweating, and extreme fatigue. This dangerous disease can easily become fatal if not treated properly.
By 1942, Britain had conducted enough laboratory research on anthrax to transition into real-world testing. Gruinard Island, located in one of the most sparsely populated areas of the UK, became the perfect testing ground.
In the first test, the research team tethered approximately 60 sheep at varying distances around a container of anthrax spores, which were detonated with explosives. All of the sheep subsequently died. In other experiments, bombers flew over the island to drop bombs containing anthrax spores, resulting in even more animal fatalities. The scientists later returned to the island suited in HAZMAT gear to analyze the sheep and conduct autopsies to better understand the disease’s effects.
The official stance of the British government was that the experiments on Gruinard Island were purely defensive and aimed at preparing for the possibility of a biological weapons attack on the country. However, Britain had devised several theoretical plans regarding the use of this new type of weapon against real enemies. One such plan was Operation Vegetarian, which involved dropping linseed cakes containing anthrax spores onto German livestock fields to destroy food supplies and infect thousands of people.
By April 1943, the Allies had stockpiled 5 million linseed cakes. However, “cool heads” prevailed, and the Allies decided not to deploy any anthrax weapons throughout the war.
After the war, Gruinard Island was strictly off-limits except for a group of scientists who arrived to test the soil for signs of contamination. The results indicated that inactive anthrax spores could remain viable in the soil for decades. Locals began to express discomfort and impatience, describing the area as “a pollution monster.”
By the 1980s, realizing that the problem would not resolve itself, the British government initiated a comprehensive cleanup project. The project team, vaccinated against anthrax and wearing protective gear, returned to the island to decontaminate it by spraying the surface soil with seawater and formaldehyde, using 50 liters of solution for each square meter of land.
In the summer of 1987, a flock of sheep was introduced back to Gruinard Island, and there were no signs of infection. Consequently, the following year, the British Ministry of Defence officially declared the island “safe.” Gruinard was then sold back to the heirs of the original owner for £500. However, the island remains uninhabited.
