Organometallic compounds are also called organometallic compounds. Compounds formed by the combination of alkyl groups (including methyl, ethyl, propyl, butyl, etc.). ) and aryl (phenyl, etc. ) and metal atoms, and carbon directly combined with metal atoms. It can form stable organometallic compounds with metals such as lithium, sodium, magnesium, calcium, zinc, cadmium, mercury, beryllium, aluminum, tin and lead. Generally speaking, it can be divided into two types: alkyl metal compounds and aromatic metal compounds. The former is methylmercury compound, tetraethyl lead and tributyltin, which have an impact on the environment; The latter is phenylmercuric salt, triphenyltin, etc. There are also organic manganese compounds used as gasoline antiknock agents, such as manganese tricarbonyl cyclopentadiene. Most of these substances are synthetic, but lead, mercury, cadmium, tin and so on. It will be methylated (or alkylated) in nature, for example, from inorganic mercury to methylmercury. Most of them are due to the action of underwater microorganisms, while in fish they are transformed from various organisms. Generally, organometallic compounds are fat-soluble, which are easier to pass through the biofilm than inorganic metals, are absorbed by the intestinal wall, and enter the cerebral vessels and placenta in more quantities; Therefore, it has stronger biological toxicity. Alkyl metal compounds are easy to cause central nervous system disorders. In vivo, the microsomal drug metabolizing enzyme system, which is mainly composed of organs such as liver, removes alkyl and aromatic groups from organometallic compounds and eventually becomes inorganic metals. The toxicity caused by biofilm is most sensitive to birds.