The report, Tritium on Tap, produced by the Sierra Club of Canada, warned that radioactive emissions from various nuclear plants across the country have more than doubled over the past decade. The figures were based on statistics compiled by the Canadian Nuclear Safety Commission which measured pollution coming from the plants. "Once in our body, tritium enters our DNA, fat, proteins and carbohydrates -- and that is where it does its damage from close range," said the Sierra Club report. "It is a carcinogen and causes birth defects."