Exactly 11 years ago in the ASA Newsletter 90-5, Dr. Graham Pearson's very timely article was published on neutralization of anthrax on Gruinard Island. Today this article, as reprinted below, is even more timely.

Gruinard Island Returns to Civil Use
by Dr. Graham S Pearson, The Director UK Chemical Defense Establishment

September 1990. Gruinard Island lies at 57o56' North and 5o35' West in North West Scotland in Gruinard Bay. The island is about 2 km long and 1 km across at its widest point. Its 522 acres of rocky land rise to 106 meters above sea level and are covered with coarse grasses, heather, bracken and peat. A spit of shingle extends from the south-east corner of the island to provide a convenient landing for vessels from the mainland, some 1.2 km distant.
          It seems that in 1881 six people lived on the island and ruins of cottages and field walls can still be seen. It is uncertain when the last inhabitant left the island but by the 1930s the island was used solely for sheep grazing, rough shooting, fishing, collecting birds eggs and a favourite local picnic spot.
          The UK had perceived possible biological warfare-related activity in several nations in the 1930s. The war brought continuing intelligence that the Axis powers were intent on acquiring a capability or indeed that they might have already developed that means. The War cabinet decided that the feasibility of biological warfare should be investigated so as to be able to retaliate in kind were biological weapons to be used against the UK.
          Accordingly, in late 1940 an autonomous highly secret group known as Biology Department, Porton (BDP) was set up within the then Chemical Defense Experimental Station (CDES) at Porton Down, with a mandate to assess the feasibility and hazard of biological warfare and to consider the means for retaliation in kind which might be employed if the Axis powers were to use biological warfare.
          Trials with harmless simulants disseminated from bombs had been done on the Porton Down range to show that a considerable number of inhalable particles could be produced up to 250 yards away from a small bomb. Laboratory work with animals had also resulted in knowledge that several species of animals inhaling anthrax spores could produce deaths in animals through inhalation of the aerosol formed on exploding.
          In 1942, the War Department identified Gruinard Island as a site for urgent field trials on biological warfare. It was declared a prohibited place, requisitioned and became known as "X-base". Trials were done in the summer of 1942 and 1943. The first year trials were with a 30 pound bomb and the second year with a 4 pound bomb. The smaller bomb was designed to form part of a cluster bomb containing over 100 of the 4 pound bombs. This concept was as a conjoint United Kingdom, Canada and United States effort but in the event, the end of the second World War halted the United Kingdom's urgency to acquire a tactical biological weapon. In the interim the War Cabinet requirement for a means to retaliate in kind was fulfilled by the modest stockpiling of lindseed cattlecakes, each containing a lethal dose of anthrax spores. These would, if required, have been disseminated from bomber aircraft to fall into the pastures of Germany, where they would be found and eaten by the cattle. The stockpile of cattlecake was kept at Porton Down and destroyed after the second World War.
          In 1945 when the owner sought the return of Gruinard Island, the Ministry of Supply recognized that the island was contaminated as a result of the wartime experiments and consequently it could not be derequisitioned until it was deemed safe. In 1946, the State agreed to acquire the island and to take on the onus of responsibility. The owner or her heirs and beneficiaries would be able to repurchase the island for the sale price of 500 when it was declared "Fit for habitation by man and beast".
          From 1947 to 1968, the island was visited by staff from the Microbiological Research Establishment (MRE) at Porton Down and samples of soil collected for assay of spores: no progressive lessening of contamination was found.
          In 1979, when the Chemical Defense Establishment (CDE) took over responsibility, a small joint CDE/MRE team made a survey. This was followed by a more detailed series of CDE surveys in the early 1980s which included the study as to how decontamination of the terrain might be achieved.
          An improved assay technique together with the surveys showed that the contamination by anthrax spores was not widespread but was in fact effectively limited to the immediate area of the World War II experiments, in all an area of about three acres.
          The importance attached to the return of Gruinard Island to civil ownership was such that the Ministry of Defense considered it essential to have an independent evaluation of the studies carried out by CDE. In 1985 the Chief Scientific Adviser of the Ministry of Defense invited the President of the Royal Society to nominate a chairman of an Independent Advisory Group on Gruinard Island. Professor W D P Stewart, FRS, Professor of Biology, University of Dundee and Secretary and Deputy Chairman of the Agricultural and Food Research Council (AFRC) was nominated as Chairman and he selected five other eminent scientists to serve as members of the advisory group.
          The Terms of Reference of the Independent Advisory Group were as follows:
  a. To review relevant scientific work undertaken by the Chemical Defense Establishment relating to anthrax and Gruinard Island.
  b. To advise on any proposed decontamination treatment of Gruinard Island and its environmental consequences.
  c. To advise on what post treatment operations are required, following any decontamination and to review the evidence on the efficacy of any treatment.
  d. To advise on the prospect for the return of the island to civil use after any treatment and to consider agricultural implications relating to Gruinard Island.
          The Independent Advisory Group reviewed the work carried out by CDE and concluded that in the light of CDE's studies of the historical trials records, results of assays of spores in the immediate trials area and sheep paddock and the negative results obtained outside such areas, the area of decontamination had been correctly identified.
          The Independent Advisory Group then reviewed the CDE conclusions on the suitability of formaldehyde decontamination. These were that the soil of the main contaminated areas could be decontaminated by irrigation with 5% of formaldehyde and seawater and that this should be applied by a contractor with appropriate technical expertise. In addition, the Institute of Terrestrial Ecology had advised that the island contained no rare plants and animals and that the ecological effects of decontamination with formaldehyde and seawater would be negligible in the long-term especially if artificial reseeding with a special upland grass mixture was carried out after the decontamination treatment. The Languard Group were identified as the best suitable contractor and arrangements were made to carry out the decontamination in June to August 1986.
          The decontamination was carried out by first spraying the area to be decontaminated with a herbicide. The dead vegetation was then burnt off so as to ensure that the subsequent application of the 5% of formaldehyde in seawater solution would reach all areas of the surface. The solution was then applied to the surface of the area to be decontaminated through tubing which had been perforated in such a way as to give even distribution. The application was carried out in careful sequence so as to ensure that 50 litres were applied to every square metre of the ten acres to be treated without any run-off occurring.
          The efficacy of the decontamination treatment was assessed by the taking of soil samples in October 1986. Duplicate soil samples were taken: one set of samples were analyzed by the CDE at Porton Down and the duplicate set analyzed at the Central Veterinary Laboratory at Weybridge in Surrey. These soil samples were taken to a depth of 50 cm or generally to bedrock. In all, some 130 sites were sampled by taking twin cores; each core was analyzed as a number of slices. These analyses showed that the decontamination treatment had been extremely effective. Antrax spores were only detectable in small quantities in a very few places. These specific areas were treated in July 1987. Further soil samples, analyzed in October 1987, showed no traces of anthrax spores.
          The Independent Group recommended that the sera of indigenous rabbits be examined for antibodies to anthrax. No such antibodies were detected. In addition, they recommended that as a demonstration of confidence that the whole island could now be used in the same way as the mainland, a local farmer should graze part of his flock of sheep on the island for six months. Accordingly 40 sheep were grazed on Gruinard Island from May to October 1987. They were inspected monthly by the District Veterinary Officer and returned to the mainland in October 1987 in excellent condition.
          The Independent Advisory Group concluded in its final 1988 report: "On the basis of all of the evidence now available, we believe that the chances of persons or animals contracting anthrax on Gruinard Island are so remote that the island can be returned to civil use".
          On 1 May 1990, the island was repurchased by the heirs of the original owner for 500. Thus in 1990 nearly 50 years after the island was acquired to meet the requirements of World War II, the Ministry of Defense and the Chemical Defense Establishment are delighted that the island has been successfully decontaminated so that the island can now be returned to civil ownership. Editor's Note: Dr. Graham Scott Pearson is The Director, The Chemical Defense Establishment, Porton Down, Salisbury, Wiltshire, England. Dr. Pearson has taken time from his very busy schedule to pen three articles for the ASA Newsletter and its community of professionals around the world. These articles included The CBW Spectrum in 90-1, National Labs 3 in 90-3 and now this article on the closing chapter of Gruinard Island. For this effort all of us want to express our greatest thanks. As a special note, we have heard from many professionals on how very informative and how well Dr. Pearson's "The CBW Spectrum" and Professor Chen Ji-Sheng's "Chemical Agents and Non-US Developmental Activities'' (90-3) track. These were this year's most important and thought provoking articles.

End of ASA article originally published in October 1990.

Editor's Note: Dr. Pearson's contributions to the worldwide audience of the ASA Newsletter, as well as to many other journals of note, have been exceptional in content and clarity. And as per his 1990 The CBW Spectrum, he has been able to very accurately forecast where the world was headed in the advances in technology in CBWA development.

For the Professional in Government and Industry with an interest in Nuclear, Biological and Chemical Defense, Disarmament and Verification; Emergency and Disaster Medical Planning; Industrial Health and Safety; and Environmental Protection