noxious(poisonous, toxic)
pollute(contaminate, defile)
pollutant(Rivers in the neighbourhood were polluted by the chemical wastes from the factories.)
pollution(air pollution, noise pollution, soil pollution, water pollution)
contaminate(The Department of Resources notified the town coucil that the water supply was contaminated.)
waste(solid waste固体废物)
sewage
fume
habitat(home, environment, The polar region is the habitat of polar bear.)
balance(I lost my balance and fell)
ecosystem
fauna
decibel
ozonosphere
Always aim for achievement and forget about success. --Helen Hayes