Astana – Every year on August 29, the international community celebrates the International Day against Nuclear Tests. In Kazakhstan, the date carries a particularly strong symbolic meaning: on August 29, 1991, the Semipalatinsk nuclear test site was closed. Forty-two years earlier, on August 29, 1949, the Soviet Union had conducted its first nuclear explosion at the same site. The date therefore symbolizes, in the country’s history, both the beginning of a tragic era and a conscious choice in favour of peace, disarmament and international cooperation.The year 2026 marks the 35th anniversary of the closure of the Semipalatinsk nuclear test site, as well as the 30th anniversary of the opening for signature of the Comprehensive Nuclear-Test-Ban Treaty. It also marks the 20th anniversary of the signing of the Semipalatinsk Treaty, which established a nuclear-weapon-free zone in Central Asia.“These are three anniversaries that link Kazakhstan’s national memory to the global effort to prevent new nuclear tragedies,” notes a statement sent to Fides by the Embassy of Kazakhstan to the Holy See.Between 1949 and 1989, 456 nuclear tests were conducted at the Semipalatinsk test site: 30 ground tests, 86 atmospheric tests and 340 underground tests. Their consequences affected vast areas and entire generations, with around 1.5 million people impacted, including descendants of those directly exposed. Research continues to document the long-term medical, psychological and social consequences of radiation exposure. Semipalatinsk therefore remains a warning of the human cost of nuclear testing for individuals, families, societies and the environment.This history gave rise to a powerful anti-nuclear movement. In 1989, the international “Nevada-Semipalatinsk” movement was established, bringing together millions of supporters around the world calling for an end to nuclear testing. This mobilization also helped bring the tests to an end, and on August 29, 1991, the site was permanently closed, shortly before Kazakhstan formally declared its independence.Following the dissolution of the Soviet Union, Kazakhstan found itself in possession of one of the world’s largest nuclear arsenals at the time: approximately 1,400 nuclear warheads, together with the associated strategic infrastructure. Kazakhstan decided to renounce this arsenal, undertaking a voluntary nuclear disarmament process after the end of the Cold War. In 1994, Kazakhstan joined the Treaty on the Non-Proliferation of Nuclear Weapons as a non-nuclear-weapon state. By 1995, the last nuclear warheads had been removed from its territory. The country signed the Comprehensive Nuclear-Test-Ban Treaty on September 30, 1996, and ratified it on May 14, 2002.The history of Semipalatinsk did not end with the closure of the test site. Kazakhstan had to secure the former military infrastructure, study contaminated areas and create the conditions for their rehabilitation. To this end, the National Nuclear Center of the Republic of Kazakhstan was established in 1992. Between 2008 and 2021, a comprehensive environmental survey of the entire former test site was carried out, involving more than two million field measurements and over 100,000 laboratory analyses. In 2023, the Semipalatinsk Nuclear Safety Zone was established, subject to a special legal regime providing for restricted access to contaminated areas, their remediation and continuous radiation and environmental monitoring. In this way, a territory once created for nuclear testing has gradually been transformed into a space for scientific research and international cooperation, completing the transition from a military infrastructure to a place devoted to the pursuit of peaceful science.The policy also had a regional impact. On September 8, 2006, the Treaty on a Nuclear-Weapon-Free Zone in Central Asia was signed in Semipalatinsk by Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan, and entered into force in 2009. Central Asia – a region where nuclear weapons had previously been not only tested but also deployed – thus became the first nuclear-weapon-free zone in the Northern Hemisphere. In the territory where one of the world’s largest nuclear test sites operated for decades, five states gave legal expression to a shared choice in favour of a nuclear-free space.At the international level, Kazakhstan has worked to give the memory of Semipalatinsk a universal dimension. At the initiative of the Kazakh state, on December 2, 2009, the United Nations General Assembly adopted Resolution 64/35, proclaiming August 29 the International Day against Nuclear Tests and thus making the date of the site’s closure part of the memory of all humanity.In 2015, the United Nations General Assembly adopted the “Universal Declaration for the Achievement of a Nuclear-Weapon-Free World”, promoted by Kazakhstan, which is a member of the Treaty on the Prohibition of Nuclear Weapons, signed in 2018 and ratified on August 29, 2019. The Holy See also signed and ratified the treaty on September 20, 2017, becoming one of its first member state.“President of the Republic of Kazakhstan Kassym-Jomart Tokayev has called for the resumption of dialogue among nuclear powers and for multilateral action capable of reducing the risk of nuclear weapons being used. In a message dated March 5, 2026, Pope Leo XIV expressed the hope that “the nuclear threat may never again condition the future of humanity”. Kazakhstan and the Holy See are united not only by a moral aspiration for a world without nuclear weapons, but also by a concrete commitment, under international law, to achieving this goal,” the statement notes.The statement sent to Fides by the Embassy of Kazakhstan concludes: “This is one of the central meanings of August 29: preserving the memory of what has been experienced and transforming that memory into responsibility for a future shaped not by nuclear threats and fear, but by human dignity, trust and peace.”
