Production
Polyethylene terephthalate (PET) is an aliphatic polyester. It is obtained from the polycondensation reaction of the monomers obtained either by esterification reaction between terephthalic acid and ethylene glycol, or
trans-esterification reaction between ethylene glycol and dimethyl terephthalate[1].As of 2022, ethylene glycol is made from ethene found in natural gas, while terephthalic acid comes from p-xylene made from crude oil [2].
Properties and uses
PET has a semi-crystalline form when stable. It is recyclable and shows resistance to impact, moisture, alcohols, and solvents. PET is used in packaging, fabrics. It is used in films to mold parts for automotive and electronics [1].

Toxicity
Volatile particles causes gastrointestinal obstruction, mental sicknesses, asthma, allergy, and chronic pneumonia. Microplastics consist of additives and monomers, reported as endocrine disrupters according to the report, also antimony goes as a conceivable cancer-causing agent in the human body[3].

[1] https://omnexus.specialchem.com/selection-guide/polyethylene-terephthalate-pet-plastic
[2] https://en.wikipedia.org/
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8755403/