Chemicals refers to pure substance and a mixture of various elements, whether natural or artificial, are all chemicals. According to the American chemical abstracts registry, the world has as many as seven million kinds of chemicals, which have been listed as a commodity has more than 10 species, there are more than 70,000 kinds of frequently used worldwide each year on emerging chemicals have over 1000 species.
Family Day is widely used in a variety of chemicals. Such as pesticides, disinfectants, detergents, dry cleaners, they are useful, but also emit toxic gases. Aniline is highly toxic for the production of a small amount of household chemicals such as paint, pesticides, fungicides. Widely used as solvents, fire extinguishing agent, PCE CCl4, used as degreasers
of CH3CCl3, used as refrigerants, blowing agents CHF2Cl chlorinated hydrocarbons are the main sources of pollution.