Poland during communist times had active programs in the development of weapons of mass destruction, including nuclear weapons, but since then has signed the Nuclear Non-Proliferation Treaty. Poland also is working with Russia to help eliminate the large stockpiles of chemical and biological weapons developed by the Warsaw Pact countries.
Nuclear weapons
Although not officially a nuclear power, Poland was classified as having an active nuclear weapons program by NATO during the Cold War. Nuclear research began in Poland in the early 1960s, with the main goal of achieving a nuclear reaction by the end of the decade. In late 1960s a controlled nuclear fission reaction was achieved. In the 1970s further research resulted in the generation of fusion neutrons through convergent shockwaves. In the 1980s nuclear research focused mostly on the development and analysis of micro-nuclear reactions with the utilization of Uranium 235 isotope. After the collapse of the Warsaw Pact, and the Fall of Communism nuclear research was transfered from military control to the Institute of Atomic Energy (IAE). Poland operated two nuclear reactors at Swierk, near Warsaw, termed EWA and MARIA. In 1995 the EWA reactor was decommissioned. Non-military related nuclear research continues at the MARIA reactor.
Chemical Weapons
Poland's chemical weapons production originates from before World War II. Prior to the outbreak of the war Poland had developed and stockpiled a large quantity of mustard gas, but never authorized its release during combat. After the war stockpiles of the agent were increased, and current estimates of remanents of these range from hundreds to thousands of tons. Other chemical and blister agents that were stockpiled during the Cold War by Poland include Lewisite, VX, Sarin, Soman, Tabun, SN gas , CS gas, Nitrogen Mustard , Phosgene, CN gas, BZ gas , Butolin , Saxitoxin, and Enterotoxin. After the fall of communism Poland greatly reduced its weapons stockpiles, and undertook a proactive program of dissarmament. In 2004 during the G8 summit the Polish-Russian agreement in the sphere of chemical weapons destruction was reached. The chemical weapons agreement will assist Russia in disposing of its Lewisite stockpiles.
Biological Weapons
The extent of Poland's biological weapons production is unclear, although research was done by both the military and communist regime laboratories during the Cold War on various dangerous agents. Military research of biological agents included Encephalitis, Influenza, Yellow Fever, Typhus, Anthrax, Brucellosis, Cholera, Plague, Typhoid, Dysentry, and limited access to smallpox through cooperation with the Soviet Union laboratories. After the fall of communism Poland undertook the destruction of its biological weapons, along with its general policy of dissarmament. In 1997 a NATO Advanced Research Workshop (ARW) entitled "Conversion of Former Biological Weapons Facilities: Development and Production of Prophylactic, Diagnostic and Therapeutic Measures for Countering Diseases" was held at the "Frederic Joliot-Curie" Institute for Radiobiology and Radiohygiene with Poland, Russia and Ukraine agreeing to the conventions of the workshop.