If plastic was made in 1907 how do they know it may take up to 1000 years to decompose?

Question

If plastic was made in 1907 how do they know it may take up to 1000 years to decompose?

In: Chemistry

Answer 1

You know how when you are downloading/copying/transferring files on your computer, it says how long it’ll take, even though it isn’t completed yet. Calculation is based on how much competed over a short period of time, much like plastic decomposition can be observed in a few years, to determine how long before it’s mostly broken down.