Title: Why Marin County Has The Highest Breast Cancer Rates In The US
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Content: Fig. 1: San Francisco Bay Area, with Marin County in  upper left corner. Even more surprising, the radiocesium reported in the  paper had been measured by the Lawrence Livermore Nuclear Weapons Lab,  from the north end of San Francisco Bay to the coastal waters at the tip  of Baja California, Mexico. By mapping the pattern of breast cancer in  Marin County, I identified the San Francisco Bay shoreline of the Marin  County peninsula as the environment where the highest rates of breast cancer  occur in the county. The deepest part of San Francisco Bay is offshore  from Marin, and the highest volume of sediment-laden water passes through  this area each day with the tides. The lowest breast cancer rates are along  the Pacific coastline of Marin. The spatial distribution of breast cancer  made it clear that there had to be an environmental cause. Large areas  of mudflats and estuaries along the bay side shoreline of Marin, like the  Welsh seacoast, provide a low energy environment for radioactive contaminated  fine sediments to settle out. CONTAMINATION OF REGIONAL WATER SUPPLIES
Most of the fresh water coming into San Francisco Bay  is from the Sierra Nevada Mountains east of the California coastline, a  very high mountain range running north and south along the border with  Nevada.