Where is bay pollution coming from? Scientists turn to the currents

In mangroves behind Vizcaya, plastic bottles, tampon applicators and bits of styrofoam regularly get trapped in the tangle of roots as if captured in a storm drain. Out the mouth of the Miami River and across Biscayne Bay on Miami Beach, stormwater flushes human and animal wastes and an array of foul stuff. On Virginia Key, a vial of blood sticks out of the sand.