In linguistics and grammar, a pronoun (abbreviated PRO) is a word that substitutes for a noun or noun phrase. It is a particular case of a pro-form.
Some of the most significant toxic effects associated with substances used or emitted in plastic production include: 13. 1  Benzene (PET, PVC, LDPE, PP): known human carcinogen, workplace exposure depresses the nervous system. 2  Chromium oxide (HDPE, LDPE): suspected carcinogen, damaging to the liver and nervous system.ome of the most significant toxic effects associated with substances used or emitted in plastic production include: 13. 1  Benzene (PET, PVC, LDPE, PP): known human carcinogen, workplace exposure depresses the nervous system. 2  Chromium oxide (HDPE, LDPE): suspected carcinogen, damaging to the liver and nervous system.
Plastic is made of monomers. Organic plastics are polymers, composed of monomers (repeating units). A polymer is a chain of molecules repeated again and again.lastics are made of many repeating units of monomers to form a long chain known as a polymer. Different types of plastics have different monomers. Examples of polymers that â¦ are plastics include polyvinyl chloride (PVC) and polystyrene.