Well the relative impact isn't that high, though I was pretty shocked to learn how much plastic is contained in tampons in other countries. My napkin math says that a whole life of using these full-plastics tampons equals about 1000 miles of driving an average-mpg car (11000 tampons, 10g of plastic per tampon, 25mpg as the national average efficiency).
So car-sharing one month for a 20 mile commute has about the same impact as never using disposable tampons for the whole life.
So car-sharing one month for a 20 mile commute has about the same impact as never using disposable tampons for the whole life.