Those elements will last in the rock record

Those elements will last in the rock record,even in our bones and teeth for millions of years.And in just 50 years, we've made enough plastic,at least 8 billion metric tons,to cover the whole world in a thin film.People's farming, fishing, and forestry will also show up as a before and after in any such strata because it's those kinds of activities that are causing unique species of plants and animals to die out.