The Pilgrims settled near Cape Cod in Massachusetts more than three and a half centuries ago, and at the first Thanksgiving feast, they ate cranberries plucked from local bogs. The cranberry harvest remains a New England tradition. Each Fall, tourists flock to watch the vibrant red berries bob atop fields of bright blue water. But, last month, Massachusetts health officials found traces of a suspected carcinogen in more than a dozen Cape cranberry bogs. The chemical, ethylene di-bromide, was found in aviation fuel dumped decades ago at a military base on the Cape. The contamination is ruining some cranberry harvests and renewing worries about the region’s water supply. Living On Earth’s Liz Lempert reports.