Subject(s): Environment -- Atmosphere -- Water -- Soil -- Environmental Toxicology -- Environment : Earth, human interface with environment, types of environment, environmental segments, vertical temperature of atmosphere, heat budget of earth's atmospheric system -- Biogeochemical cycle of environment : water, carbon, oxygen, nitrogen, phosphorus, Sulphur cycle, biodistribution of elements -- Chemical composition of atmosphere, chemical and photochemical reactions in atmosphere, air pollution, industrial pollution, vehicular pollution, instrumental techniques for estimation of various pollutants in atmosphere -- Water : Characteristics of water, water pollution, sources of water pollution, management of water -- Soil : Formation of soil and its characteristics, soil pollution, control of soil pollution -- Radioactive pollution : Radioactive pollution -- Environmental toxicology : environmental toxicology