We need to have a long exchange over this. My null-hypothesis - supported by the evidence you have provided - is that the large plastic is doing the killing and when it gets small it passes through with little effect - like grains of sand. Because clearly grains of sand are bigger than nanometer and they don't block up digestive tracts. The albatross didn't die from endocrine disruption did it.
That's how science works. From your evidence my null hypothesis is proven.
We should know what it does to individual cells - particularly if we are creating scare stories around it.
