1. In 1901, the Royal Insititute for Research and Testing in Water Supply and Waste Disposal is founded, becoming the Royal State Insititute for Water Hygiene in 1913, the Prussian State Institute for Water, Soil and Air in 1923, the Imperial Institute for Water, Soil and Air in 1942, before finally settling down as the Institute for Water, Soil and Air Hygiene under the Federal Health Office in 1952. In 1994, it became a department of the FEA, merging with it completely in 1999.

  2. NABU (then the BfV) starts a campaign to save the yellow-billed egret and the bird of paradise, which are hunted for their feathers (for use in women's hats).

  3. The Emscher cooperative is founded to regulate sewage treatment in the Ruhrgebiet. Similar cooperatives follow: Ruhrverband, Lippeverband, Niersverband, Wupperverband.

  4. The Congress concludes that "poor water quality threatened fisheries with total ruin."

  5. Prussia sets up a State Office for the Care of Natural Heritage.

  6. NABU (then the BfV) organises Germany's first Bird Conservation Day in Berlin.

  7. The Lakeview Gusher Number One was an immense out-of-control pressurized oil well in the Midway-Sunset Oil Field in Kern County, California, resulting in what is regarded as one of the largest oil spills in history, lasting 18 months and releasing 1.400.000m³ of crude oil.

  8. The "Verein Naturschutzpark" sets up a protected nature park on the Lüneburg Heath.

  9. Ammonia needed for nitrogen fertiliser and munitions is produced synthetically.

  10. The first international conference on nature conservation takes place in Bern.

  11. Compensation and widows' pensions granted in case of illness caused by aromatic nitrogen compounds.

  12. The Oppau explosion occurred on September 21, 1921 when a tower silo storing 4,500 tonnes of a mixture of ammonium sulfate and ammonium nitrate fertilizer exploded at a BASF plant in Oppau, now part of Ludwigshafen, Germany, killing 561 people and injuring about 2,000 more. About 80 percent of all buildings in Oppau were destroyed.

  13. A Prussian act to protect trees is passed in 1922, with positive effects in conurbations, above all.

  14. Accident insurance is extended, at first to cover 11 occupational illnesses.

  15. The first German Nature Conservation Day (Deutscher Naturschutztag DNT) took place in Munich from 26 July - 28 July 1925. Since 1957 the conference is held every two years.

  16. Hermann Joseph Müller (1890 - 1965) discovers X-rays to be agents of mutation.

  17. NABU (then the BfV) starts a campaign against destruction of the countryside through land clearance.

  18. A "fog disaster" in Maastal near Lüttich claims 100 lives.

  19. The first patent for production of synthetic fibres is granted. Under the Nazi policy of self-sufficiency, the industry expands greatly in the 1930s.

  20. World Animal Day was started in 1931 at a convention of ecologists in Florence as a way of highlighting the plight of endangered species. Since then it has grown to encompass all kinds of animal life and is widely celebrated in countries throughout the world. October 4 was chosen as World Animal Day as it is the Feast Day of St Francis of Assisi, the patron saint of animals.

  21. Sewage containing mercury is released by Chisso's chemicals works into Minimata Bay in Japan. The mercury accumulates in sea creatures, leading eventually to mercury poisoning in the population.

  22. Over these 40 years, the lake's phosphate concentrations rise from zero to 26 mg/m_, its nitrate content from 600 mg/m_ to 800 mg/m_. The mass of phytoplankton is a factor of twenty greater. The whitefish catch falls to an all-time low in 1963. A convention on safeguarding the water quality in the Bodensee is accepted in 1961. Eutrophication in the Bodensee remains stable from 1975.

  23. Otto Hahn and Fritz Straßmann discover nuclear fission.

  24. Discovery of insecticide DDT. P. Müller receives the Nobel Prize in 1948. DDT has been banned in Germany since 1972.

  25. Invention of 2,4,5, trichlorophenoxyacetic acid. During the Vietnam War (1965-1971), it is used as a defoliant under the codename Agent Orange. It is expected that contaminated soil will need over a century to regenerate.

  26. "Little Boy", an atomic bomb with a 60 kg core of uranium 235, explodes over Hiroshima with the power of 13.5 kt of explosives. By the end of 1945, 140,000 have died as a consequence.

  27. "Fat Man", a 22 kt atomic bomb is dropped on Nagasaki, killing 70,000 immediately.

  28. The International Convention for the Regulation of Whaling aims to conserve large whale populations. It is legally binding in civil law.

  29. The Economic Commission for Europe is responsible for a great many fundamental environmental agreements, especially on air quality, water quality, industrial waste and environmental impact assessments.

  30. The Organisation for Economic Cooperation and Development is set up in Paris as part of the Marshall Plan. It has an environment department, which deals above all with the relationship between economic activity and the environment. The OECD regularly publishes reports on the environment in OECD countries and other studies.

  31. The 1948 Donora smog was an historic air inversion wall of smog that killed 20 and sickened 7,000 people in Donora, Pennsylvania in the United States, a mill town on the Monongahela River, 24 miles southeast of Pittsburgh.

  32. Each year, on 23 March, the World Meteorological Organization, its 188 Members and the worldwide meteorological community celebrate World Meteorological Day. This Day commemorates the entry into force, on that date in 1950, of the WMO Convention creating the Organization. Subsequently, in 1951, WMO was designated a specialized agency of the United Nations System. The United Nations weather agency is marking World Meteorological Day by calling for improvements to climate observation technologies to help people and economies adapt to climate change, climate variability and extreme weather.

  33. In Ohio (USA), a factory releases c. 200 t of radioactive uranium dust into the environment, with government permission.

  34. The Federal Republic of Germany became the 64th member state of UNESCO on 11 July 1951.

  35. In 1952, the first incidents of mercury poisoning appear in the population of Minimata Bay in Japan, caused by consumption of fish polluted with mercury, bringing over 500 fatalities. Since then, Japan has had the strictest environmental laws in the industrialised world.

  36. The worst smog on record hangs over London for five days. 4,000 more than average die during the period. The smog was created by accumulated sulphur dioxide from coal burning.

  37. Arbor Day is celebrated in many countries around the world. The idea originally came from Nebraska. Arbor Day was established by J. Sterling Morton in 1872. In November 1951 the Food and Agriculture Organisation (FAO) arranged for all member nations to set aside one particular day each year to celebrate Arbor Day. For Germany it is April 25.

  38. The west of the lake has consumed all of its oxygen. Mayflies larvae die on the lake bed, and cannot decompose, due to the lack of oxygen. In addition, concentrations of fertilising nitrate and phosphate ions have trebled between the 1930s and the 1970s.

  39. A thermal reaction releases TCDD in a production plant, injuring 55. Investigation after 30 years shows

  40. Early in the morning on March 1, 1954, the hydrogen bomb, code named Bravo, was detonated on the surface of the reef in the northwestern corner of Bikini Atoll and created widespread radioactive contamination.