Why is plastic bad for your environment?

plastic water bottles are bad for the environment because first they START decomposing after 700 years, all the chemicals in the plastic go into the air we breathe and the places where they make water bottles (factories) are putting toxic fumes in the air plus they have to go get the oil used to make the plastic, then bring it back to the factory wihich puts the gas from the car in the air! plus we could could be using the oil for much better things than plastic bottles with lasts for minutes.