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.
Description. Benzene Natural sources include volcanoes and forest fires. Benzene is also a natural constituent of crude oil and gasoline. Its most widely-produced derivatives include styrene, which is used to make polymers and plastics, phenol for resins and adhesives and cyclohexane, which is used to manufacture Nylon.escription. Benzene Natural sources include volcanoes and forest fires. Benzene is also a natural constituent of crude oil and gasoline. Its most widely-produced derivatives include styrene, which is used to make polymers and plastics, phenol for resins and adhesives and cyclohexane, which is used to manufacture Nylon.