- Atmospheric Protection/Air Quality Control/Air Pollution 7
- Environment, general 6
- Environmental Chemistry 6
- Environmental Health 6
- Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution 6
- Ecotoxicology 5
- Atmospheric Sciences 3
- Environmental Management 2
- Terrestrial Pollution 2
- Earth Sciences, general 1
- Math. Appl. in Environmental Science 1
- Meteorology 1
- Pollution, general 1
- Space Sciences (including Extraterrestrial Physics, Space Exploration and Astronautics) 1
- Sustainable Development 1
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