It must expel it to a high degree. I can't imagine any significant amount of 52 credit cards worth of plastic a year being retained by the body. That would mean

It must expel it to a high degree. I can't imagine any significant amount of 52 credit cards worth of plastic a year being retained by the body. That would mean that I have approximately 1500 credit cards worth of plastic in my body just layin' around after my 29 years of livin'. I can tell ya - I'd notice 1500 credit cards worth of plastic hanging out in my body. That's 5g * 1500 = 7.5kg (16.5lbs) of plastic.