Downstream residents fear that increased cancer rates (7) may be related to pollution from the oil sands industry. Based in part on results from the Regional AquaticMonitoring Program(RAMP), industry, government and related agencies claim that human health and the environment are not at risk from oil sands development (8, 9) and that sources of elements and polycyclic aromatic compounds (PAC) in the AR and its tributaries are natural (10).